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iio: temperature: Adding support for MLX90632

PATCH Superseded Crt Mori 3 participants 5 messages Nov 29, 2017 – Dec 5, 2017

Subsystems (2)

v1 of 13 Superseded Latest is v13 →

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Crt Mori

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#0 lore raw

PATCH 1/2 iio: temperature: Adding support for MLX90632

Melexis has just released Infra Red temperature sensor MLX90632 used for contact-less temperature measurement. Driver provides basic functionality for reporting object (and ambient) temperature with support for object emissivity.

---
 MAINTAINERS                        |   7 +
 drivers/iio/temperature/Kconfig    |  12 +
 drivers/iio/temperature/Makefile   |   1 +
 drivers/iio/temperature/mlx90632.c | 802 +++++++++++++++++++++++++++++++++++++
 4 files changed, 822 insertions(+)
 create mode 100644 drivers/iio/temperature/mlx90632.c
MAINTAINERS +7 -0
index 2d3d750b19c0..81aec02b08b8 100644
@@ -8690,6 +8690,13 @@ W:	http://www.melexis.com
 S:	Supported
 F:	drivers/iio/temperature/mlx90614.c
 
+MELEXIS MLX90632 DRIVER
+M:	Crt Mori <[email protected]>
+L:	[email protected]
+W:	http://www.melexis.com
+S:	Supported
+F:	drivers/iio/temperature/mlx90632.c
+
 MELFAS MIP4 TOUCHSCREEN DRIVER
 M:	Sangwon Jee <[email protected]>
 W:	http://www.melfas.com
drivers/iio/temperature/Kconfig +12 -0
index 5378976d6d27..82e4a62745e2 100644
@@ -43,6 +43,18 @@ config MLX90614
 	  This driver can also be built as a module. If so, the module will
 	  be called mlx90614.
 
+config MLX90632
+	tristate "MLX90632 contact-less infrared sensor with medical accuracy"
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  If you say yes here you get support for the Melexis
+	  MLX90632 contact-less infrared sensor with medical accuracy
+	  connected with I2C.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called mlx90632.
+
 config TMP006
 	tristate "TMP006 infrared thermopile sensor"
 	depends on I2C
drivers/iio/temperature/Makefile +1 -0
index ad1d668de546..44644fe01bc9 100644
@@ -5,6 +5,7 @@
 obj-$(CONFIG_HID_SENSOR_TEMP) += hid-sensor-temperature.o
 obj-$(CONFIG_MAXIM_THERMOCOUPLE) += maxim_thermocouple.o
 obj-$(CONFIG_MLX90614) += mlx90614.o
+obj-$(CONFIG_MLX90632) += mlx90632.o
 obj-$(CONFIG_TMP006) += tmp006.o
 obj-$(CONFIG_TMP007) += tmp007.o
 obj-$(CONFIG_TSYS01) += tsys01.o
drivers/iio/temperature/mlx90632.c new file +802 -0

802 lines not on this page · raw message

Signature · 1 line
2.15.0
maintainer
#1 lore raw
Quoted 6 lines · On Wed, 29 Nov 2017 23:07:49 +0100 Crt Mori <[email protected]> wrote:

Melexis has just released Infra Red temperature sensor MLX90632 used for contact-less temperature measurement. Driver provides basic functionality for reporting object (and ambient) temperature with support for object emissivity.

Various comments inline.

Quoted 69 lines
---
 MAINTAINERS                        |   7 +
 drivers/iio/temperature/Kconfig    |  12 +
 drivers/iio/temperature/Makefile   |   1 +
 drivers/iio/temperature/mlx90632.c | 802 +++++++++++++++++++++++++++++++++++++
 4 files changed, 822 insertions(+)
 create mode 100644 drivers/iio/temperature/mlx90632.c
MAINTAINERS +7 -0
index 2d3d750b19c0..81aec02b08b8 100644
@@ -8690,6 +8690,13 @@ W:	http://www.melexis.com
 S:	Supported
 F:	drivers/iio/temperature/mlx90614.c
 
+MELEXIS MLX90632 DRIVER
+M:	Crt Mori <[email protected]>
+L:	[email protected]
+W:	http://www.melexis.com
+S:	Supported
+F:	drivers/iio/temperature/mlx90632.c
+
 MELFAS MIP4 TOUCHSCREEN DRIVER
 M:	Sangwon Jee <[email protected]>
 W:	http://www.melfas.com
drivers/iio/temperature/Kconfig +12 -0
index 5378976d6d27..82e4a62745e2 100644
@@ -43,6 +43,18 @@ config MLX90614
 	  This driver can also be built as a module. If so, the module will
 	  be called mlx90614.
 
+config MLX90632
+	tristate "MLX90632 contact-less infrared sensor with medical accuracy"
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  If you say yes here you get support for the Melexis
+	  MLX90632 contact-less infrared sensor with medical accuracy
+	  connected with I2C.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called mlx90632.
+
 config TMP006
 	tristate "TMP006 infrared thermopile sensor"
 	depends on I2C
drivers/iio/temperature/Makefile +1 -0
index ad1d668de546..44644fe01bc9 100644
@@ -5,6 +5,7 @@
 obj-$(CONFIG_HID_SENSOR_TEMP) += hid-sensor-temperature.o
 obj-$(CONFIG_MAXIM_THERMOCOUPLE) += maxim_thermocouple.o
 obj-$(CONFIG_MLX90614) += mlx90614.o
+obj-$(CONFIG_MLX90632) += mlx90632.o
 obj-$(CONFIG_TMP006) += tmp006.o
 obj-$(CONFIG_TMP007) += tmp007.o
 obj-$(CONFIG_TSYS01) += tsys01.o
drivers/iio/temperature/mlx90632.c new file +2 -0
new file mode 100644
index 000000000000..05c7d943e504
@@ -0,0 +1,802 @@
+/*
+ * mlx90632.c - Melexis MLX90632 contactless IR temperature sensor

drivers/iio/temperature/mlx90632.c line 12

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+ *
+ * Copyright (c) 2017 Melexis <[email protected]>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * Driver for the Melexis MLX90632 I2C 16-bit IR thermopile sensor
+ */
+#include <asm/byteorder.h>

Don't think this should ever be included in a driver. What do you need it for?

drivers/iio/temperature/mlx90632.c line 23

Quoted 11 lines
drivers/iio/temperature/mlx90632.c new file +11 -0
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/math64.h>
+#include <linux/of.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/unaligned/be_byteshift.h>

why?

Quoted 68 lines
drivers/iio/temperature/mlx90632.c new file +68 -0
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+/* Memory sections addresses */
+#define MLX90632_ADDR_RAM	0x4000 /* Start address of ram */
+#define MLX90632_ADDR_EEPROM	0x2480 /* Start address of user eeprom */
+
+/* EEPROM addresses - used at startup */
+#define MLX90632_EE_CTRL	0x24d4 /* Control register initial value */
+#define MLX90632_EE_I2C_ADDR	0x24d5 /* I2C address register initial value */
+#define MLX90632_EE_VERSION	0x240b /* EEPROM version reg address */
+#define MLX90632_EE_P_R		0x240c /* P_R calibration register 32bit */
+#define MLX90632_EE_P_G		0x240e /* P_G calibration register 32bit */
+#define MLX90632_EE_P_T		0x2410 /* P_T calibration register 32bit */
+#define MLX90632_EE_P_O		0x2412 /* P_O calibration register 32bit */
+#define MLX90632_EE_Aa		0x2414 /* Aa calibration register 32bit */
+#define MLX90632_EE_Ab		0x2416 /* Ab calibration register 32bit */
+#define MLX90632_EE_Ba		0x2418 /* Ba calibration register 32bit */
+#define MLX90632_EE_Bb		0x241a /* Bb calibration register 32bit */
+#define MLX90632_EE_Ca		0x241c /* Ca calibration register 32bit */
+#define MLX90632_EE_Cb		0x241e /* Cb calibration register 32bit */
+#define MLX90632_EE_Da		0x2420 /* Da calibration register 32bit */
+#define MLX90632_EE_Db		0x2422 /* Db calibration register 32bit */
+#define MLX90632_EE_Ea		0x2424 /* Ea calibration register 32bit */
+#define MLX90632_EE_Eb		0x2426 /* Eb calibration register 32bit */
+#define MLX90632_EE_Fa		0x2428 /* Fa calibration register 32bit */
+#define MLX90632_EE_Fb		0x242a /* Fb calibration register 32bit */
+#define MLX90632_EE_Ga		0x242c /* Ga calibration register 32bit */
+
+#define MLX90632_EE_Gb		0x242e /* Gb calibration register 16bit */
+#define MLX90632_EE_Ka		0x242f /* Ka calibration register 16bit */
+
+#define MLX90632_EE_Ha		0x2481 /* Ha customer calib value reg 16bit */
+#define MLX90632_EE_Hb		0x2482 /* Hb customer calib value reg 16bit */
+
+/* Register addresses - volatile */
+#define MLX90632_REG_I2C_ADDR	0x3000 /* Chip I2C address register */
+
+/* Control register address - volatile */
+#define MLX90632_REG_CONTROL	0x3001 /* Control Register address */
+#define   MLX90632_CFG_PWR_MASK		GENMASK(2, 1) /* PowerMode Mask */
+/* PowerModes statuses */
+#define MLX90632_PWR_STATUS(ctrl_val) (ctrl_val << 1)
+#define MLX90632_PWR_STATUS_HALT MLX90632_PWR_STATUS(0) /* hold */
+#define MLX90632_PWR_STATUS_SLEEP_STEP MLX90632_PWR_STATUS(1) /* sleep step*/
+#define MLX90632_PWR_STATUS_STEP MLX90632_PWR_STATUS(2) /* step */
+#define MLX90632_PWR_STATUS_CONTINUOUS MLX90632_PWR_STATUS(3) /* continuous*/
+
+/* Device status register - volatile */
+#define MLX90632_REG_STATUS	0x3fff /* Device status register */
+#define   MLX90632_STAT_BUSY		BIT(10) /* Device busy indicator */
+#define   MLX90632_STAT_EE_BUSY		BIT(9) /* EEPROM busy indicator */
+#define   MLX90632_STAT_BRST		BIT(8) /* Brown out reset indicator */
+#define   MLX90632_STAT_CYCLE_POS	GENMASK(6, 2) /* Data position */
+#define   MLX90632_STAT_DATA_RDY	BIT(0) /* Data ready indicator */
+
+/* RAM_MEAS address-es for each channel */
+#define MLX90632_RAM_1(meas_num)	(MLX90632_ADDR_RAM + 3 * meas_num)
+#define MLX90632_RAM_2(meas_num)	(MLX90632_ADDR_RAM + 3 * meas_num + 1)
+#define MLX90632_RAM_3(meas_num)	(MLX90632_ADDR_RAM + 3 * meas_num + 2)
+
+/* Magic constants */
+#define MLX90632_EEPROM_VERSION	0xff05 /* EEPROM DSP version for constants */
+#define MLX90632_ID_MEDICAL	0x01ff /* EEPROM Medical device id */
+#define MLX90632_ID_CONSUMER	0x02ff /* EEPROM Consumer device id */
+#define MLX90632_EEPROM_WRITE_KEY 0x554C /* EEPROM write key 0x55 and 0x4c */
+#define MLX90632_RESET_CMD	0x0006 /* Reset sensor (address or global) */

drivers/iio/temperature/mlx90632.c line 101

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+#define MLX90632_REF_12		12LL /**< ResCtrlRef value of Ch 1 or Ch 2 */
+#define MLX90632_REF_3		12LL /**< ResCtrlRef value of Channel 3 */
+
+#define TENTO3			1000LL
+#define TENTO4			10000LL
+#define TENTO5			100000LL
+#define TENTO6			1000000LL
+#define TENTO7			10000000LL
+#define TENTO10			10000000000LL
+#define TENTO12			1000000000000LL

Umm. The numbers describe the constants rather better than the defines ;) Just use the numbers if you need them!

Quoted 56 lines
drivers/iio/temperature/mlx90632.c new file +56 -0
+
+struct mlx90632_data {
+	struct i2c_client *client;
+	struct mutex lock; /* Multiple reads for single measurement */
+	struct regmap *regmap;
+	u16 emissivity;
+};
+
+static const struct regmap_range mlx90632_volatile_reg_range[] = {
+	regmap_reg_range(MLX90632_REG_CONTROL, MLX90632_REG_I2C_ADDR),
+	regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
+	regmap_reg_range(MLX90632_RAM_1(0),
+			 MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_volatile_regs_tbl = {
+	.yes_ranges = mlx90632_volatile_reg_range,
+	.n_yes_ranges = ARRAY_SIZE(mlx90632_volatile_reg_range),
+};
+
+static const struct regmap_range mlx90632_read_reg_range[] = {
+	regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
+	regmap_reg_range(MLX90632_EE_CTRL, MLX90632_EE_I2C_ADDR),
+	regmap_reg_range(MLX90632_EE_Ha, MLX90632_EE_Hb),
+	regmap_reg_range(MLX90632_REG_CONTROL, MLX90632_REG_I2C_ADDR),
+	regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
+	regmap_reg_range(MLX90632_RAM_1(0),
+			 MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_readable_regs_tbl = {
+	.yes_ranges = mlx90632_read_reg_range,
+	.n_yes_ranges = ARRAY_SIZE(mlx90632_read_reg_range),
+};
+
+static const struct regmap_range mlx90632_no_write_reg_range[] = {
+	regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
+	regmap_reg_range(MLX90632_RAM_1(0),
+			 MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_writeable_regs_tbl = {
+	.no_ranges = mlx90632_no_write_reg_range,
+	.n_no_ranges = ARRAY_SIZE(mlx90632_no_write_reg_range),
+};
+
+static const struct regmap_config mlx90632_regmap = {
+	.reg_bits = 16,
+	.val_bits = 16,
+
+	.volatile_table = &mlx90632_volatile_regs_tbl,
+	.rd_table = &mlx90632_readable_regs_tbl,
+	.wr_table = &mlx90632_writeable_regs_tbl,
+
+	.use_single_rw = true,
+	.reg_format_endian = REGMAP_ENDIAN_BIG,

drivers/iio/temperature/mlx90632.c line 167

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+	.val_format_endian = REGMAP_ENDIAN_BIG,
+	.cache_type = REGCACHE_RBTREE,
+};
+
+static u64 mlx90632_int_sqrt(u64 x)
+{
+	u64 b, m, y = 0;
+
+	if (BITS_PER_LONG != 32)
+		return int_sqrt(x);

needs a comment on why...
Ideally propose a standard 64 bit routine if one is needed for 32 bit machines.

Quoted 30 lines
drivers/iio/temperature/mlx90632.c new file +30 -0
+
+	if (x <= 1)
+		return x;
+
+	m = 1ULL << (64 - 2);
+	while (m != 0) {
+		b = y + m;
+		y >>= 1;
+
+		if (x >= b) {
+			x -= b;
+			y += m;
+		}
+		m >>= 2;
+	}
+	return y;
+}
+
+static s32 mlx90632_pwr_set_sleep_step(struct regmap *regmap)
+{
+	return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+				  MLX90632_CFG_PWR_MASK,
+				  MLX90632_PWR_STATUS_SLEEP_STEP);
+}
+
+static s32 mlx90632_pwr_set_step(struct regmap *regmap)
+{
+	return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+				  MLX90632_CFG_PWR_MASK,
+				  MLX90632_PWR_STATUS_STEP);

drivers/iio/temperature/mlx90632.c line 207

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+}
+
+static s32 mlx90632_pwr_continuous(struct regmap *regmap)
+{
+	return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+				  MLX90632_CFG_PWR_MASK,
+				  MLX90632_PWR_STATUS_CONTINUOUS);
+}
+
+static int mlx90632_start_measurement(struct mlx90632_data *data)

Looks superficially to me like this is actually waiting for a reading to complete rather than just starting it? If so change the name to reflect that.

Quoted 15 lines
drivers/iio/temperature/mlx90632.c new file +15 -0
+{
+	int ret, tries = 100;
+	unsigned int reg_status;
+
+	ret = regmap_update_bits(data->regmap, MLX90632_REG_STATUS,
+				 MLX90632_STAT_DATA_RDY, 0);
+	if (ret < 0)
+		return ret;
+
+	while (tries-- > 0) {
+		ret = regmap_read(data->regmap, MLX90632_REG_STATUS,
+				  &reg_status);
+		if (ret < 0)
+			return ret;
+		if (reg_status & MLX90632_STAT_DATA_RDY)

drivers/iio/temperature/mlx90632.c line 232

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+			break;
+		usleep_range(10000, 11000);
+	}
+
+	if (tries < 0) {
+		dev_err(&data->client->dev, "data not ready");
+		return -ETIMEDOUT;
+	}
+
+	return (reg_status & MLX90632_STAT_CYCLE_POS) >> 2;

This is a non obvious return value so I would suggest adding some documentation to say what is going on here..

drivers/iio/temperature/mlx90632.c line 236

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+}
+
+static int mlx9032_channel_new_select(int ret, uint8_t *channel_new,
+				      uint8_t *channel_old)

don't use ret as a name for a variable being passed in. Rather confusing!

drivers/iio/temperature/mlx90632.c line 247

Quoted 11 lines
drivers/iio/temperature/mlx90632.c new file +11 -0
+{
+	if (ret == 1) {
+		*channel_new = 1;
+		*channel_old = 2;
+	} else if (ret == 2) {
+		*channel_new = 2;
+		*channel_old = 1;
+	} else {
+		return ret;
+	}
+	return 0;

Can't get here...

Quoted 69 lines
drivers/iio/temperature/mlx90632.c new file +69 -0
+}
+
+static int mlx90632_read_ambient_raw(struct regmap *regmap,
+				     s16 *ambient_new_raw, s16 *ambient_old_raw)
+{
+	int ret;
+	unsigned int read_tmp;
+
+	ret = regmap_read(regmap, MLX90632_RAM_3(1), &read_tmp);
+	if (ret < 0)
+		return ret;
+	*ambient_new_raw = (s16)read_tmp;
+
+	ret = regmap_read(regmap, MLX90632_RAM_3(2), &read_tmp);
+	if (ret < 0)
+		return ret;
+	*ambient_old_raw = (s16)read_tmp;
+
+	return ret;
+}
+
+static int mlx90632_read_object_raw(struct regmap *regmap,
+				    int start_measurement_ret,
+				    s16 *object_new_raw, s16 *object_old_raw)
+{
+	int ret;
+	unsigned int read_tmp;
+	s16 read;
+	u8 channel = 0;
+	u8 channel_old = 0;
+
+	ret = mlx90632_channel_new_select(start_measurement_ret, &channel,
+					  &channel_old);
+	if (ret != 0)
+		return ret;
+
+	ret = regmap_read(regmap, MLX90632_RAM_2(channel), &read_tmp);
+	if (ret < 0)
+		return ret;
+
+	read = (s16)read_tmp;
+
+	ret = regmap_read(regmap, MLX90632_RAM_1(channel), &read_tmp);
+	if (ret < 0)
+		return ret;
+	*object_new_raw = (read + (s16)read_tmp) / 2;
+
+	ret = regmap_read(regmap, MLX90632_RAM_2(channel_old), &read_tmp);
+	if (ret < 0)
+		return ret;
+	read = (s16)read_tmp;
+
+	ret = regmap_read(regmap, MLX90632_RAM_1(channel_old), &read_tmp);
+	if (ret < 0)
+		return ret;
+	*object_old_raw = (read + (s16)read_tmp) / 2;
+
+	return ret;
+}
+
+static int mlx90632_read_all_channel(struct mlx90632_data *data,
+				     s16 *ambient_new_raw, s16 *ambient_old_raw,
+				     s16 *object_new_raw, s16 *object_old_raw)
+{
+	s32 ret, tm_ret;
+
+	mutex_lock(&data->lock);
+	tm_ret = mlx90632_start_measurement(data);
+	if (tm_ret >= 0) {

drivers/iio/temperature/mlx90632.c line 326

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+		ret = mlx90632_read_ambient_raw(data->regmap, ambient_new_raw,
+						ambient_old_raw);
+		if (ret >= 0) {
+			ret = mlx90632_read_object_raw(data->regmap, tm_ret,
+						       object_new_raw,
+						       object_old_raw);
+		}
+	} else {
+		ret = tm_ret;
+	}

Use something cleaner like

	mutex_lock(&data->lock);
	ret = mlx90632_start_measurement(data);
	if (ret < 0)
		goto unlock;
	ret = mlx90632_read_ambient_raw(data->regmap, ambient_new_raw,
					ambient_old_raw);
	if (ret < 0)
		goto unlock;

	ret = mlx90632_read_object_raw(data->regmap, tm_ret,
				       object_new_raw,
				       object_old_raw);

unlock:

Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+	mutex_unlock(&data->lock);
+	return ret;
+}
+
+static int mlx90632_read_ee_register(struct regmap *regmap, u16 reg_lsb,
+				     s32 *reg_value)

drivers/iio/temperature/mlx90632.c line 342

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+{
+	s32 ret;
+	unsigned int read;
+	__le32 value;
+
+	ret = regmap_read(regmap, reg_lsb, &read);
+	if (ret < 0)
+		return ret;
+
+	value = cpu_to_le32(read);

Why would you be converting to le32 to then do
calculations in here using it at cpu endianness?
(guessing you want le32_to_cpu..)

hmm isn't any relevant endian conversion wrapped up in regmap anyway?

Quoted 94 lines
drivers/iio/temperature/mlx90632.c new file +94 -0
+
+	ret = regmap_read(regmap, reg_lsb + 1, &read);
+	if (ret < 0)
+		return ret;
+
+	value = (cpu_to_le32(read) << 16) | (value & 0xffff);
+
+	*reg_value = le32_to_cpu(value);
+	return 0;
+}
+
+static s64 mlx90632_preprocess_temp_amb(s16 ambient_new_raw,
+					s16 ambient_old_raw, s16 Gb)
+{
+	s64 VR_Ta, kGb, tmp;
+
+	kGb = ((s64)Gb * TENTO3) >> 10ULL;
+	VR_Ta = (s64)ambient_old_raw * TENTO6 +
+		kGb * div64_s64(((s64)ambient_new_raw * TENTO3),
+			(MLX90632_REF_3));
+	tmp = div64_s64(
+			 div64_s64(((s64)ambient_new_raw * TENTO12),
+				   (MLX90632_REF_3)), VR_Ta);
+	return div64_s64(tmp << 19ULL, TENTO3);
+}
+
+static s64 mlx90632_preprocess_temp_obj(s16 object_new_raw, s16 object_old_raw,
+					s16 ambient_new_raw,
+					s16 ambient_old_raw, s16 Ka)
+{
+	s64 VR_IR, kKa, tmp;
+
+	kKa = ((s64)Ka * TENTO3) >> 10ULL;
+	VR_IR = (s64)ambient_old_raw * TENTO6 +
+		kKa * div64_s64(((s64)ambient_new_raw * TENTO3),
+			(MLX90632_REF_3));
+	tmp = div64_s64(
+			div64_s64(((s64)((object_new_raw + object_old_raw) / 2)
+				   * TENTO12), (MLX90632_REF_12)), VR_IR);
+	return div64_s64(tmp << 19ULL), TENTO3);
+}
+
+static s32 mlx90632_calc_temp_ambient(s16 ambient_new_raw, s16 ambient_old_raw,
+				      s32 P_T, s32 P_R, s32 P_G, s32 P_O,
+				      s16 Gb)
+{
+	s64 Asub, Bsub, Ablock, Bblock, Cblock, AMB, sum;
+
+	AMB = mlx90632_preprocess_temp_amb(ambient_new_raw, ambient_old_raw,
+					   Gb);
+	Asub = ((s64)P_T * TENTO10) >> 44ULL;
+	Bsub = AMB - (((s64)P_R * TENTO3) >> 8ULL);
+	Ablock = Asub * (Bsub * Bsub);
+	Bblock = (div64_s64(Bsub * TENTO7, P_G)) << 20ULL;
+	Cblock = ((s64)P_O * TENTO10) >> 8ULL;
+
+	sum = div64_s64(Ablock, TENTO6) + Bblock + Cblock;
+
+	return div64_s64(sum, TENTO7);
+}
+
+static s32 mlx90632_calc_temp_object_iteration(s32 prev_object_temp, s64 object,
+					       s64 TAdut, s32 Fa, s32 Fb,
+					       s32 Ga, s16 Ha, s16 Hb,
+					       u16 emissivity)
+{
+	s64 calcedKsTO, calcedKsTA, ir_Alpha, TAdut4, Alpha_corr;
+	s64 Ha_customer, Hb_customer;
+
+	Ha_customer = ((s64)Ha * TENTO6) >> 14ULL;
+	Hb_customer = ((s64)Hb * 100) >> 10ULL;
+
+	calcedKsTO = ((s64)((s64)Ga * (prev_object_temp - 25 * TENTO3)
+			     * TENTO3)) >> 36LL;
+	calcedKsTA = ((s64)(Fb * (TAdut - 25 * TENTO6))) >> 36LL;
+	Alpha_corr = div64_s64((((s64)(Fa * TENTO10) >> 46LL) * Ha_customer),
+			       TENTO3);
+	Alpha_corr *= ((s64)(1 * TENTO6 + calcedKsTO + calcedKsTA));
+	Alpha_corr = emissivity * div64_s64(Alpha_corr, TENTO5);
+	Alpha_corr = div64_s64(Alpha_corr, TENTO3);
+	ir_Alpha = div64_s64((s64)object * TENTO7, Alpha_corr);
+	TAdut4 = (div64_s64(TAdut, TENTO4) + 27315) *
+		(div64_s64(TAdut, TENTO4) + 27315) *
+		(div64_s64(TAdut, TENTO4)  + 27315) *
+		(div64_s64(TAdut, TENTO4) + 27315);
+
+	return (mlx90632_int_sqrt(
+			 mlx90632_int_sqrt(ir_Alpha * TENTO12 + TAdut4)
+			) - 27315 - Hb_customer) * 10;
+}
+
+static s32 mlx90632_calc_temp_object(s64 object, s64 ambient, s32 Ea, s32 Eb,
+				     s32 Fa, s32 Fb, s32 Ga, s16 Ha, s16 Hb,
+				     u16 tmp_emi)

drivers/iio/temperature/mlx90632.c line 446

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+{
+	s64 kTA, kTA0, TAdut;
+	s64 temp = 25000;
+	s8 i;
+
+	kTA = (Ea * TENTO3) >> 16LL;
+	kTA0 = (Eb * TENTO3) >> 8LL;
+	TAdut = div64_s64(((ambient - kTA0) * TENTO6), kTA) + 25 * TENTO6;
+
+	for (i = 0; i < 5; ++i) {

comment on why iterations are needed would be good here.

Quoted 118 lines
drivers/iio/temperature/mlx90632.c new file +118 -0
+		temp = mlx90632_calc_temp_object_iteration(temp, object, TAdut,
+							   Fa, Fb, Ga, Ha, Hb,
+							   tmp_emi);
+	}
+	return temp;
+}
+
+static int mlx90632_calc_object_dsp105(struct mlx90632_data *data, int *val)
+{
+	s32 ret;
+	s32 Ea, Eb, Fa, Fb, Ga;
+	unsigned int read_tmp;
+	s16 Ha, Hb, Gb, Ka;
+	s16 ambient_new_raw, ambient_old_raw, object_new_raw, object_old_raw;
+	s64 object, ambient;
+
+	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ea, &Ea);
+	if (ret < 0)
+		return ret;
+	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Eb, &Eb);
+	if (ret < 0)
+		return ret;
+	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fa, &Fa);
+	if (ret < 0)
+		return ret;
+	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fb, &Fb);
+	if (ret < 0)
+		return ret;
+	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ga, &Ga);
+	if (ret < 0)
+		return ret;
+	ret = regmap_read(data->regmap, MLX90632_EE_Ha, &read_tmp);
+	if (ret < 0)
+		return ret;
+	Ha = (s16)read_tmp;
+	ret = regmap_read(data->regmap, MLX90632_EE_Hb, &read_tmp);
+	if (ret < 0)
+		return ret;
+	Hb = (s16)read_tmp;
+	ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
+	if (ret < 0)
+		return ret;
+	Gb = (s16)read_tmp;
+	ret = regmap_read(data->regmap, MLX90632_EE_Ka, &read_tmp);
+	if (ret < 0)
+		return ret;
+	Ka = (s16)read_tmp;
+
+	ret = mlx90632_read_all_channel(data,
+					&ambient_new_raw, &ambient_old_raw,
+					&object_new_raw, &object_old_raw);
+	if (ret < 0)
+		return ret;
+
+	ambient = mlx90632_preprocess_temp_amb(ambient_new_raw,
+					       ambient_old_raw, Gb);
+	object = mlx90632_preprocess_temp_obj(object_new_raw,
+					      object_old_raw,
+					      ambient_new_raw,
+					      ambient_old_raw, Ka);
+
+	*val = mlx90632_calc_temp_object(object, ambient, Ea, Eb, Fa, Fb, Ga,
+					 Ha, Hb, data->emissivity);
+	return 0;
+}
+
+static int mlx90632_calc_ambient_dsp105(struct mlx90632_data *data, int *val)
+{
+	s32 ret;
+	unsigned int read_tmp;
+	s32 PT, PR, PG, PO;
+	s16 Gb;
+	s16 ambient_new_raw, ambient_old_raw;
+
+	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_R, &PR);
+	if (ret < 0)
+		return ret;
+	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_G, &PG);
+	if (ret < 0)
+		return ret;
+	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_T, &PT);
+	if (ret < 0)
+		return ret;
+	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_O, &PO);
+	if (ret < 0)
+		return ret;
+	ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
+	if (ret < 0)
+		return ret;
+	Gb = (s16)read_tmp;
+
+	ret = mlx90632_read_ambient_raw(data->regmap, &ambient_new_raw,
+					&ambient_old_raw);
+	*val = mlx90632_calc_temp_ambient(ambient_new_raw, ambient_old_raw,
+					  PT, PR, PG, PO, Gb);
+	return ret;
+}
+
+static int mlx90632_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *channel, int *val,
+			     int *val2, long mask)
+{
+	struct mlx90632_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_PROCESSED:
+		switch (channel->channel2) {
+		case IIO_MOD_TEMP_AMBIENT:
+			ret = mlx90632_calc_ambient_dsp105(data, val);
+			if (ret < 0)
+				return ret;
+			return IIO_VAL_INT;
+		case IIO_MOD_TEMP_OBJECT:
+			ret = mlx90632_calc_object_dsp105(data, val);
+			if (ret < 0)
+				return ret;
+			return IIO_VAL_INT;

drivers/iio/temperature/mlx90632.c line 574

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_CALIBEMISSIVITY:
+		if (data->emissivity == 1000) {
+			*val = 1;
+			*val2 = 0;
+		} else {
+			*val = 0;
+			*val2 = data->emissivity;

Odd given you are reporting as int + nano
this goes from 1.0 to 0.000000999 in one step?
Seems unlikely.. If it is true then a comment
is needed.

The write is int + micro but this would still be wrong without a factor of 1000.

Quoted 8 lines
drivers/iio/temperature/mlx90632.c new file +8 -0
+		}
+		return IIO_VAL_INT_PLUS_NANO;
+
+	default:
+		return -EINVAL;
+	}
+}
+

drivers/iio/temperature/mlx90632.c line 592

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+static int mlx90632_write_raw(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *channel, int val,
+			      int val2, long mask)
+{
+	struct mlx90632_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_CALIBEMISSIVITY:
+		if (val < 0 || val2 < 0 || val > 1 ||
+		    (val == 1 && val2 != 0))

I'd add a comment describing what this is doing. I think it is checking for 0-1.0 inclusive?

Quoted 76 lines
drivers/iio/temperature/mlx90632.c new file +76 -0
+			return -EINVAL;
+		data->emissivity = val * 1000 + val2 / 1000;
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_chan_spec mlx90632_channels[] = {
+	{
+		.type = IIO_TEMP,
+		.modified = 1,
+		.channel2 = IIO_MOD_TEMP_AMBIENT,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+	},
+	{
+		.type = IIO_TEMP,
+		.modified = 1,
+		.channel2 = IIO_MOD_TEMP_OBJECT,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+			BIT(IIO_CHAN_INFO_CALIBEMISSIVITY),
+	},
+};
+
+static const struct iio_info mlx90632_info = {
+	.read_raw = mlx90632_read_raw,
+	.write_raw = mlx90632_write_raw,
+};
+
+#ifdef CONFIG_PM
+static int mlx90632_sleep(struct mlx90632_data *data)
+{
+	dev_dbg(&data->client->dev, "Requesting sleep");
+	return mlx90632_pwr_set_sleep_step(data->regmap);
+}
+
+static int mlx90632_wakeup(struct mlx90632_data *data)
+{
+	dev_dbg(&data->client->dev, "Requesting wake-up");
+	return mlx90632_pwr_continuous(data->regmap);
+}
+#endif
+
+static int mlx90632_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	struct iio_dev *indio_dev;
+	struct mlx90632_data *mlx90632;
+	struct regmap *regmap;
+	int ret;
+	unsigned int read;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*mlx90632));
+	if (!indio_dev) {
+		dev_err(&client->dev, "Failed to allocate device");
+		return -ENOMEM;
+	}
+
+	regmap = devm_regmap_init_i2c(client, &mlx90632_regmap);
+	if (IS_ERR(regmap)) {
+		ret = PTR_ERR(regmap);
+		dev_err(&client->dev, "Failed to allocate regmap: %d\n", ret);
+		return ret;
+	}
+
+	mlx90632 = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	mlx90632->client = client;
+	mlx90632->regmap = regmap;
+
+	mutex_init(&mlx90632->lock);
+	mlx90632_wakeup(mlx90632);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->name = id->name;
+	indio_dev->modes = INDIO_DIRECT_MODE;

drivers/iio/temperature/mlx90632.c line 678

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+	indio_dev->info = &mlx90632_info;
+	indio_dev->channels = mlx90632_channels;
+	indio_dev->num_channels = ARRAY_SIZE(mlx90632_channels);
+
+	ret = regmap_read(mlx90632->regmap, MLX90632_EE_VERSION, &read);
+	if (ret < 0) {
+		dev_err(&client->dev, "read of version failed: %d\n", ret);
+		return ret;
+	}
+	if (read == (MLX90632_EEPROM_VERSION & MLX90632_ID_MEDICAL)) {

This is odd. Why the bitwise and of what look to be two different things entirely?

Quoted 5 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+		dev_dbg(&client->dev,
+			"Detected Medical EEPROM calibration %x", read);
+	} else if (read == (MLX90632_EEPROM_VERSION & MLX90632_ID_CONSUMER)) {
+		dev_dbg(&client->dev,
+			"Detected Consumer EEPROM calibration %x", read);

drivers/iio/temperature/mlx90632.c line 693

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+	} else {
+		dev_err(&client->dev,
+			"Chip EEPROM version mismatch %x (expected %x)",
+			read, MLX90632_EEPROM_VERSION);
+		return -EPROTONOSUPPORT;
+	}
+
+	mlx90632->emissivity = 1000;
+
+	return devm_iio_device_register(&client->dev, indio_dev);

Don't use devm version. You are (correctly) manually unwinding this in the remove (as you have pm to deal with after removing the interfaces). This will result in a double free I think... return iio_device_register is the way to go.

I'm a bit confused that you don't seem to set up runtime pm anywhere... I would assume we would be looking at autosuspend for a device like this but it isn't enabled..

Quoted 27 lines
drivers/iio/temperature/mlx90632.c new file +27 -0
+}
+
+static int mlx90632_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct mlx90632_data *data = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	pm_runtime_disable(&client->dev);
+	if (!pm_runtime_status_suspended(&client->dev))
+		mlx90632_sleep(data);
+	pm_runtime_set_suspended(&client->dev);
+
+	return 0;
+}
+
+static const struct i2c_device_id mlx90632_id[] = {
+	{ "mlx90632", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mlx90632_id);
+
+static const struct of_device_id mlx90632_of_match[] = {
+	{ .compatible = "melexis,mlx90632" },
+	{ }
+};

drivers/iio/temperature/mlx90632.c line 730

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+MODULE_DEVICE_TABLE(of, mlx90632_of_match);
+
+#ifdef CONFIG_PM_SLEEP
+static int mlx90632_pm_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct mlx90632_data *data = iio_priv(indio_dev);
+
+	if (pm_runtime_active(dev))
+		return mlx90632_sleep(data);

I'm a little confused as to why, if the device is powered up fully and a suspend comes in we have to do less than we do in runtime pm case.

Am I missing something?

Quoted 72 lines
drivers/iio/temperature/mlx90632.c new file +72 -0
+
+	return 0;
+}
+
+static int mlx90632_pm_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct mlx90632_data *data = iio_priv(indio_dev);
+	int err;
+
+	err = mlx90632_wakeup(data);
+	if (err < 0)
+		return err;
+
+	pm_runtime_disable(dev);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int mlx90632_pm_runtime_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct mlx90632_data *mlx90632 = iio_priv(indio_dev);
+
+	regcache_sync(mlx90632->regmap);
+
+	return mlx90632_sleep(mlx90632);
+}
+
+static int mlx90632_pm_runtime_resume(struct device *dev)
+{
+	s32 ret;
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct mlx90632_data *mlx90632 = iio_priv(indio_dev);
+
+	regcache_mark_dirty(mlx90632->regmap);
+	regcache_cache_only(mlx90632->regmap, false);
+	ret = regcache_sync(mlx90632->regmap);
+	if (ret < 0) {
+		dev_err(dev, "Failed to sync regmap registers: %d\n", ret);
+		return ret;
+	}
+
+	return mlx90632_wakeup(mlx90632);
+}
+#endif
+
+static const struct dev_pm_ops mlx90632_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(mlx90632_pm_suspend, mlx90632_pm_resume)
+	SET_RUNTIME_PM_OPS(mlx90632_pm_runtime_suspend,
+			   mlx90632_pm_runtime_resume, NULL)
+};
+
+static struct i2c_driver mlx90632_driver = {
+	.driver = {
+		.name	= "mlx90632",
+		.of_match_table = mlx90632_of_match,
+		.pm	= &mlx90632_pm_ops,
+	},
+	.probe = mlx90632_probe,
+	.remove = mlx90632_remove,
+	.id_table = mlx90632_id,
+};
+module_i2c_driver(mlx90632_driver);
+
+MODULE_AUTHOR("Crt Mori <[email protected]>");
+MODULE_DESCRIPTION("Melexis MLX90632 contactless Infra Red temperature sensor driver");
+MODULE_LICENSE("GPL v2");
author maintainer
#2 lore raw

Hi Jonathan,
Definitely did not think there will be so many comments inside, but I expected few of them indeed.

See my replies inside.

Quoted 179 lines · Jonathan Cameron
Quoted 6 lines · On Wed, 29 Nov 2017 23:07:49 +0100 Crt Mori <[email protected]> wrote:

Melexis has just released Infra Red temperature sensor MLX90632 used for contact-less temperature measurement. Driver provides basic functionality for reporting object (and ambient) temperature with support for object emissivity.

Various comments inline.

Quoted 69 lines
---
 MAINTAINERS                        |   7 +
 drivers/iio/temperature/Kconfig    |  12 +
 drivers/iio/temperature/Makefile   |   1 +
 drivers/iio/temperature/mlx90632.c | 802 +++++++++++++++++++++++++++++++++++++
 4 files changed, 822 insertions(+)
 create mode 100644 drivers/iio/temperature/mlx90632.c
MAINTAINERS +7 -0
index 2d3d750b19c0..81aec02b08b8 100644
@@ -8690,6 +8690,13 @@ W:     http://www.melexis.com
 S:   Supported
 F:   drivers/iio/temperature/mlx90614.c
 
+MELEXIS MLX90632 DRIVER
+M:   Crt Mori <[email protected]>
+L:   [email protected]
+W:   http://www.melexis.com
+S:   Supported
+F:   drivers/iio/temperature/mlx90632.c
+
 MELFAS MIP4 TOUCHSCREEN DRIVER
 M:   Sangwon Jee <[email protected]>
 W:   http://www.melfas.com
drivers/iio/temperature/Kconfig +12 -0
index 5378976d6d27..82e4a62745e2 100644
@@ -43,6 +43,18 @@ config MLX90614
        This driver can also be built as a module. If so, the module will
        be called mlx90614.
 
+config MLX90632
+     tristate "MLX90632 contact-less infrared sensor with medical accuracy"
+     depends on I2C
+     select REGMAP_I2C
+     help
+       If you say yes here you get support for the Melexis
+       MLX90632 contact-less infrared sensor with medical accuracy
+       connected with I2C.
+
+       This driver can also be built as a module. If so, the module will
+       be called mlx90632.
+
 config TMP006
      tristate "TMP006 infrared thermopile sensor"
      depends on I2C
drivers/iio/temperature/Makefile +1 -0
index ad1d668de546..44644fe01bc9 100644
@@ -5,6 +5,7 @@
 obj-$(CONFIG_HID_SENSOR_TEMP) += hid-sensor-temperature.o
 obj-$(CONFIG_MAXIM_THERMOCOUPLE) += maxim_thermocouple.o
 obj-$(CONFIG_MLX90614) += mlx90614.o
+obj-$(CONFIG_MLX90632) += mlx90632.o
 obj-$(CONFIG_TMP006) += tmp006.o
 obj-$(CONFIG_TMP007) += tmp007.o
 obj-$(CONFIG_TSYS01) += tsys01.o
drivers/iio/temperature/mlx90632.c new file +2 -0
new file mode 100644
index 000000000000..05c7d943e504
@@ -0,0 +1,802 @@
+/*
+ * mlx90632.c - Melexis MLX90632 contactless IR temperature sensor

drivers/iio/temperature/mlx90632.c line 12

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+ *
+ * Copyright (c) 2017 Melexis <[email protected]>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * Driver for the Melexis MLX90632 I2C 16-bit IR thermopile sensor
+ */
+#include <asm/byteorder.h>

Don't think this should ever be included in a driver. What do you need it for?

drivers/iio/temperature/mlx90632.c line 23

Quoted 11 lines
drivers/iio/temperature/mlx90632.c new file +11 -0
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/math64.h>
+#include <linux/of.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/unaligned/be_byteshift.h>

why?

Quoted 72 lines
drivers/iio/temperature/mlx90632.c new file +72 -0
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+/* Memory sections addresses */
+#define MLX90632_ADDR_RAM    0x4000 /* Start address of ram */
+#define MLX90632_ADDR_EEPROM 0x2480 /* Start address of user eeprom */
+
+/* EEPROM addresses - used at startup */
+#define MLX90632_EE_CTRL     0x24d4 /* Control register initial value */
+#define MLX90632_EE_I2C_ADDR 0x24d5 /* I2C address register initial value */
+#define MLX90632_EE_VERSION  0x240b /* EEPROM version reg address */
+#define MLX90632_EE_P_R              0x240c /* P_R calibration register 32bit */
+#define MLX90632_EE_P_G              0x240e /* P_G calibration register 32bit */
+#define MLX90632_EE_P_T              0x2410 /* P_T calibration register 32bit */
+#define MLX90632_EE_P_O              0x2412 /* P_O calibration register 32bit */
+#define MLX90632_EE_Aa               0x2414 /* Aa calibration register 32bit */
+#define MLX90632_EE_Ab               0x2416 /* Ab calibration register 32bit */
+#define MLX90632_EE_Ba               0x2418 /* Ba calibration register 32bit */
+#define MLX90632_EE_Bb               0x241a /* Bb calibration register 32bit */
+#define MLX90632_EE_Ca               0x241c /* Ca calibration register 32bit */
+#define MLX90632_EE_Cb               0x241e /* Cb calibration register 32bit */
+#define MLX90632_EE_Da               0x2420 /* Da calibration register 32bit */
+#define MLX90632_EE_Db               0x2422 /* Db calibration register 32bit */
+#define MLX90632_EE_Ea               0x2424 /* Ea calibration register 32bit */
+#define MLX90632_EE_Eb               0x2426 /* Eb calibration register 32bit */
+#define MLX90632_EE_Fa               0x2428 /* Fa calibration register 32bit */
+#define MLX90632_EE_Fb               0x242a /* Fb calibration register 32bit */
+#define MLX90632_EE_Ga               0x242c /* Ga calibration register 32bit */
+
+#define MLX90632_EE_Gb               0x242e /* Gb calibration register 16bit */
+#define MLX90632_EE_Ka               0x242f /* Ka calibration register 16bit */
+
+#define MLX90632_EE_Ha               0x2481 /* Ha customer calib value reg 16bit */
+#define MLX90632_EE_Hb               0x2482 /* Hb customer calib value reg 16bit */
+
+/* Register addresses - volatile */
+#define MLX90632_REG_I2C_ADDR        0x3000 /* Chip I2C address register */
+
+/* Control register address - volatile */
+#define MLX90632_REG_CONTROL 0x3001 /* Control Register address */
+#define   MLX90632_CFG_PWR_MASK              GENMASK(2, 1) /* PowerMode Mask */
+/* PowerModes statuses */
+#define MLX90632_PWR_STATUS(ctrl_val) (ctrl_val << 1)
+#define MLX90632_PWR_STATUS_HALT MLX90632_PWR_STATUS(0) /* hold */
+#define MLX90632_PWR_STATUS_SLEEP_STEP MLX90632_PWR_STATUS(1) /* sleep step*/
+#define MLX90632_PWR_STATUS_STEP MLX90632_PWR_STATUS(2) /* step */
+#define MLX90632_PWR_STATUS_CONTINUOUS MLX90632_PWR_STATUS(3) /* continuous*/
+
+/* Device status register - volatile */
+#define MLX90632_REG_STATUS  0x3fff /* Device status register */
+#define   MLX90632_STAT_BUSY         BIT(10) /* Device busy indicator */
+#define   MLX90632_STAT_EE_BUSY              BIT(9) /* EEPROM busy indicator */
+#define   MLX90632_STAT_BRST         BIT(8) /* Brown out reset indicator */
+#define   MLX90632_STAT_CYCLE_POS    GENMASK(6, 2) /* Data position */
+#define   MLX90632_STAT_DATA_RDY     BIT(0) /* Data ready indicator */
+
+/* RAM_MEAS address-es for each channel */
+#define MLX90632_RAM_1(meas_num)     (MLX90632_ADDR_RAM + 3 * meas_num)
+#define MLX90632_RAM_2(meas_num)     (MLX90632_ADDR_RAM + 3 * meas_num + 1)
+#define MLX90632_RAM_3(meas_num)     (MLX90632_ADDR_RAM + 3 * meas_num + 2)
+
+/* Magic constants */
+#define MLX90632_EEPROM_VERSION      0xff05 /* EEPROM DSP version for constants */
+#define MLX90632_ID_MEDICAL  0x01ff /* EEPROM Medical device id */
+#define MLX90632_ID_CONSUMER 0x02ff /* EEPROM Consumer device id */
+#define MLX90632_EEPROM_WRITE_KEY 0x554C /* EEPROM write key 0x55 and 0x4c */
+#define MLX90632_RESET_CMD   0x0006 /* Reset sensor (address or global) */
+#define MLX90632_REF_12              12LL /**< ResCtrlRef value of Ch 1 or Ch 2 */
+#define MLX90632_REF_3               12LL /**< ResCtrlRef value of Channel 3 */
+
+#define TENTO3                       1000LL
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 101

Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+#define TENTO4                       10000LL
+#define TENTO5                       100000LL
+#define TENTO6                       1000000LL
+#define TENTO7                       10000000LL
+#define TENTO10                      10000000000LL
+#define TENTO12                      1000000000000LL

Umm. The numbers describe the constants rather better than the defines ;) Just use the numbers if you need them!

This is way shorter (line length) and more readable in my opinion. Also writing 12 times 0 is error prone :D

Quoted 62 lines
Quoted 62 lines
drivers/iio/temperature/mlx90632.c new file +62 -0
+
+struct mlx90632_data {
+     struct i2c_client *client;
+     struct mutex lock; /* Multiple reads for single measurement */
+     struct regmap *regmap;
+     u16 emissivity;
+};
+
+static const struct regmap_range mlx90632_volatile_reg_range[] = {
+     regmap_reg_range(MLX90632_REG_CONTROL, MLX90632_REG_I2C_ADDR),
+     regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
+     regmap_reg_range(MLX90632_RAM_1(0),
+                      MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_volatile_regs_tbl = {
+     .yes_ranges = mlx90632_volatile_reg_range,
+     .n_yes_ranges = ARRAY_SIZE(mlx90632_volatile_reg_range),
+};
+
+static const struct regmap_range mlx90632_read_reg_range[] = {
+     regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
+     regmap_reg_range(MLX90632_EE_CTRL, MLX90632_EE_I2C_ADDR),
+     regmap_reg_range(MLX90632_EE_Ha, MLX90632_EE_Hb),
+     regmap_reg_range(MLX90632_REG_CONTROL, MLX90632_REG_I2C_ADDR),
+     regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
+     regmap_reg_range(MLX90632_RAM_1(0),
+                      MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_readable_regs_tbl = {
+     .yes_ranges = mlx90632_read_reg_range,
+     .n_yes_ranges = ARRAY_SIZE(mlx90632_read_reg_range),
+};
+
+static const struct regmap_range mlx90632_no_write_reg_range[] = {
+     regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
+     regmap_reg_range(MLX90632_RAM_1(0),
+                      MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_writeable_regs_tbl = {
+     .no_ranges = mlx90632_no_write_reg_range,
+     .n_no_ranges = ARRAY_SIZE(mlx90632_no_write_reg_range),
+};
+
+static const struct regmap_config mlx90632_regmap = {
+     .reg_bits = 16,
+     .val_bits = 16,
+
+     .volatile_table = &mlx90632_volatile_regs_tbl,
+     .rd_table = &mlx90632_readable_regs_tbl,
+     .wr_table = &mlx90632_writeable_regs_tbl,
+
+     .use_single_rw = true,
+     .reg_format_endian = REGMAP_ENDIAN_BIG,
+     .val_format_endian = REGMAP_ENDIAN_BIG,
+     .cache_type = REGCACHE_RBTREE,
+};
+
+static u64 mlx90632_int_sqrt(u64 x)
+{
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 167

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+     u64 b, m, y = 0;
+
+     if (BITS_PER_LONG != 32)
+             return int_sqrt(x);

needs a comment on why...
Ideally propose a standard 64 bit routine if one is needed for 32 bit machines.

Problem is that int_sqrt is not strongly typed. That means 64 bit number gets truncated to 32bit on 32bit machine as you mentioned and that caused quite many headaches in my testing (worked on mobile phone, but not on beaglebone black). This solution is just stronger typing of int_sqrt function.

If you think I should put it onto math.h as a patch I can try it.

Quoted 36 lines
Quoted 36 lines
drivers/iio/temperature/mlx90632.c new file +36 -0
+
+     if (x <= 1)
+             return x;
+
+     m = 1ULL << (64 - 2);
+     while (m != 0) {
+             b = y + m;
+             y >>= 1;
+
+             if (x >= b) {
+                     x -= b;
+                     y += m;
+             }
+             m >>= 2;
+     }
+     return y;
+}
+
+static s32 mlx90632_pwr_set_sleep_step(struct regmap *regmap)
+{
+     return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+                               MLX90632_CFG_PWR_MASK,
+                               MLX90632_PWR_STATUS_SLEEP_STEP);
+}
+
+static s32 mlx90632_pwr_set_step(struct regmap *regmap)
+{
+     return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+                               MLX90632_CFG_PWR_MASK,
+                               MLX90632_PWR_STATUS_STEP);
+}
+
+static s32 mlx90632_pwr_continuous(struct regmap *regmap)
+{
+     return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+                               MLX90632_CFG_PWR_MASK,
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 207

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+                               MLX90632_PWR_STATUS_CONTINUOUS);
+}
+
+static int mlx90632_start_measurement(struct mlx90632_data *data)

Looks superficially to me like this is actually waiting for a reading to complete rather than just starting it? If so change the name to reflect that.

ok

Quoted 20 lines
Quoted 20 lines
drivers/iio/temperature/mlx90632.c new file +20 -0
+{
+     int ret, tries = 100;
+     unsigned int reg_status;
+
+     ret = regmap_update_bits(data->regmap, MLX90632_REG_STATUS,
+                              MLX90632_STAT_DATA_RDY, 0);
+     if (ret < 0)
+             return ret;
+
+     while (tries-- > 0) {
+             ret = regmap_read(data->regmap, MLX90632_REG_STATUS,
+                               &reg_status);
+             if (ret < 0)
+                     return ret;
+             if (reg_status & MLX90632_STAT_DATA_RDY)
+                     break;
+             usleep_range(10000, 11000);
+     }
+
+     if (tries < 0) {
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 232

Quoted 5 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+             dev_err(&data->client->dev, "data not ready");
+             return -ETIMEDOUT;
+     }
+
+     return (reg_status & MLX90632_STAT_CYCLE_POS) >> 2;

This is a non obvious return value so I would suggest adding some documentation to say what is going on here..

Yes, it is indeed.

Quoted 8 lines

drivers/iio/temperature/mlx90632.c line 236

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+}
+
+static int mlx9032_channel_new_select(int ret, uint8_t *channel_new,
+                                   uint8_t *channel_old)

don't use ret as a name for a variable being passed in. Rather confusing!

OK. I think I should just copy setting of channel_old and new in the only spot it is used.

Quoted 11 lines

drivers/iio/temperature/mlx90632.c line 247

Quoted 11 lines
drivers/iio/temperature/mlx90632.c new file +11 -0
+{
+     if (ret == 1) {
+             *channel_new = 1;
+             *channel_old = 2;
+     } else if (ret == 2) {
+             *channel_new = 2;
+             *channel_old = 1;
+     } else {
+             return ret;
+     }
+     return 0;
Quoted 2 lines

Can't get here...

Not true. You get here in every example other than else where channel_new and channel_old are successfully set. but I agree there is a bug in case ret=0 when it will return 0, but it will not set channels.

Quoted 92 lines
Quoted 69 lines
drivers/iio/temperature/mlx90632.c new file +69 -0
+}
+
+static int mlx90632_read_ambient_raw(struct regmap *regmap,
+                                  s16 *ambient_new_raw, s16 *ambient_old_raw)
+{
+     int ret;
+     unsigned int read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_3(1), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *ambient_new_raw = (s16)read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_3(2), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *ambient_old_raw = (s16)read_tmp;
+
+     return ret;
+}
+
+static int mlx90632_read_object_raw(struct regmap *regmap,
+                                 int start_measurement_ret,
+                                 s16 *object_new_raw, s16 *object_old_raw)
+{
+     int ret;
+     unsigned int read_tmp;
+     s16 read;
+     u8 channel = 0;
+     u8 channel_old = 0;
+
+     ret = mlx90632_channel_new_select(start_measurement_ret, &channel,
+                                       &channel_old);
+     if (ret != 0)
+             return ret;
+
+     ret = regmap_read(regmap, MLX90632_RAM_2(channel), &read_tmp);
+     if (ret < 0)
+             return ret;
+
+     read = (s16)read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_1(channel), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *object_new_raw = (read + (s16)read_tmp) / 2;
+
+     ret = regmap_read(regmap, MLX90632_RAM_2(channel_old), &read_tmp);
+     if (ret < 0)
+             return ret;
+     read = (s16)read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_1(channel_old), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *object_old_raw = (read + (s16)read_tmp) / 2;
+
+     return ret;
+}
+
+static int mlx90632_read_all_channel(struct mlx90632_data *data,
+                                  s16 *ambient_new_raw, s16 *ambient_old_raw,
+                                  s16 *object_new_raw, s16 *object_old_raw)
+{
+     s32 ret, tm_ret;
+
+     mutex_lock(&data->lock);
+     tm_ret = mlx90632_start_measurement(data);
+     if (tm_ret >= 0) {

drivers/iio/temperature/mlx90632.c line 326

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+             ret = mlx90632_read_ambient_raw(data->regmap, ambient_new_raw,
+                                             ambient_old_raw);
+             if (ret >= 0) {
+                     ret = mlx90632_read_object_raw(data->regmap, tm_ret,
+                                                    object_new_raw,
+                                                    object_old_raw);
+             }
+     } else {
+             ret = tm_ret;
+     }

Use something cleaner like

        mutex_lock(&data->lock);
        ret = mlx90632_start_measurement(data);
        if (ret < 0)
                goto unlock;
        ret = mlx90632_read_ambient_raw(data->regmap, ambient_new_raw,
                                        ambient_old_raw);
        if (ret < 0)
                goto unlock;

        ret = mlx90632_read_object_raw(data->regmap, tm_ret,
                                       object_new_raw,
                                       object_old_raw);
Quoted 1 line

unlock:

Ok sorry, professional deformation (goto).

Quoted 21 lines
Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+     mutex_unlock(&data->lock);
+     return ret;
+}
+
+static int mlx90632_read_ee_register(struct regmap *regmap, u16 reg_lsb,
+                                  s32 *reg_value)

drivers/iio/temperature/mlx90632.c line 342

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+{
+     s32 ret;
+     unsigned int read;
+     __le32 value;
+
+     ret = regmap_read(regmap, reg_lsb, &read);
+     if (ret < 0)
+             return ret;
+
+     value = cpu_to_le32(read);

Why would you be converting to le32 to then do
calculations in here using it at cpu endianness?
(guessing you want le32_to_cpu..)

Quoted 3 lines

hmm isn't any relevant endian conversion wrapped up in regmap anyway?

Regmap reads 16 bit values, but some values are 32 bit. To avoid CPU endianess affecting this, I am putting it to known time and shift values. This way I ensured it is working on any CPU. le32_to_cpu is in return value.

Quoted 97 lines
Quoted 97 lines
drivers/iio/temperature/mlx90632.c new file +97 -0
+
+     ret = regmap_read(regmap, reg_lsb + 1, &read);
+     if (ret < 0)
+             return ret;
+
+     value = (cpu_to_le32(read) << 16) | (value & 0xffff);
+
+     *reg_value = le32_to_cpu(value);
+     return 0;
+}
+
+static s64 mlx90632_preprocess_temp_amb(s16 ambient_new_raw,
+                                     s16 ambient_old_raw, s16 Gb)
+{
+     s64 VR_Ta, kGb, tmp;
+
+     kGb = ((s64)Gb * TENTO3) >> 10ULL;
+     VR_Ta = (s64)ambient_old_raw * TENTO6 +
+             kGb * div64_s64(((s64)ambient_new_raw * TENTO3),
+                     (MLX90632_REF_3));
+     tmp = div64_s64(
+                      div64_s64(((s64)ambient_new_raw * TENTO12),
+                                (MLX90632_REF_3)), VR_Ta);
+     return div64_s64(tmp << 19ULL, TENTO3);
+}
+
+static s64 mlx90632_preprocess_temp_obj(s16 object_new_raw, s16 object_old_raw,
+                                     s16 ambient_new_raw,
+                                     s16 ambient_old_raw, s16 Ka)
+{
+     s64 VR_IR, kKa, tmp;
+
+     kKa = ((s64)Ka * TENTO3) >> 10ULL;
+     VR_IR = (s64)ambient_old_raw * TENTO6 +
+             kKa * div64_s64(((s64)ambient_new_raw * TENTO3),
+                     (MLX90632_REF_3));
+     tmp = div64_s64(
+                     div64_s64(((s64)((object_new_raw + object_old_raw) / 2)
+                                * TENTO12), (MLX90632_REF_12)), VR_IR);
+     return div64_s64(tmp << 19ULL), TENTO3);
+}
+
+static s32 mlx90632_calc_temp_ambient(s16 ambient_new_raw, s16 ambient_old_raw,
+                                   s32 P_T, s32 P_R, s32 P_G, s32 P_O,
+                                   s16 Gb)
+{
+     s64 Asub, Bsub, Ablock, Bblock, Cblock, AMB, sum;
+
+     AMB = mlx90632_preprocess_temp_amb(ambient_new_raw, ambient_old_raw,
+                                        Gb);
+     Asub = ((s64)P_T * TENTO10) >> 44ULL;
+     Bsub = AMB - (((s64)P_R * TENTO3) >> 8ULL);
+     Ablock = Asub * (Bsub * Bsub);
+     Bblock = (div64_s64(Bsub * TENTO7, P_G)) << 20ULL;
+     Cblock = ((s64)P_O * TENTO10) >> 8ULL;
+
+     sum = div64_s64(Ablock, TENTO6) + Bblock + Cblock;
+
+     return div64_s64(sum, TENTO7);
+}
+
+static s32 mlx90632_calc_temp_object_iteration(s32 prev_object_temp, s64 object,
+                                            s64 TAdut, s32 Fa, s32 Fb,
+                                            s32 Ga, s16 Ha, s16 Hb,
+                                            u16 emissivity)
+{
+     s64 calcedKsTO, calcedKsTA, ir_Alpha, TAdut4, Alpha_corr;
+     s64 Ha_customer, Hb_customer;
+
+     Ha_customer = ((s64)Ha * TENTO6) >> 14ULL;
+     Hb_customer = ((s64)Hb * 100) >> 10ULL;
+
+     calcedKsTO = ((s64)((s64)Ga * (prev_object_temp - 25 * TENTO3)
+                          * TENTO3)) >> 36LL;
+     calcedKsTA = ((s64)(Fb * (TAdut - 25 * TENTO6))) >> 36LL;
+     Alpha_corr = div64_s64((((s64)(Fa * TENTO10) >> 46LL) * Ha_customer),
+                            TENTO3);
+     Alpha_corr *= ((s64)(1 * TENTO6 + calcedKsTO + calcedKsTA));
+     Alpha_corr = emissivity * div64_s64(Alpha_corr, TENTO5);
+     Alpha_corr = div64_s64(Alpha_corr, TENTO3);
+     ir_Alpha = div64_s64((s64)object * TENTO7, Alpha_corr);
+     TAdut4 = (div64_s64(TAdut, TENTO4) + 27315) *
+             (div64_s64(TAdut, TENTO4) + 27315) *
+             (div64_s64(TAdut, TENTO4)  + 27315) *
+             (div64_s64(TAdut, TENTO4) + 27315);
+
+     return (mlx90632_int_sqrt(
+                      mlx90632_int_sqrt(ir_Alpha * TENTO12 + TAdut4)
+                     ) - 27315 - Hb_customer) * 10;
+}
+
+static s32 mlx90632_calc_temp_object(s64 object, s64 ambient, s32 Ea, s32 Eb,
+                                  s32 Fa, s32 Fb, s32 Ga, s16 Ha, s16 Hb,
+                                  u16 tmp_emi)
+{
+     s64 kTA, kTA0, TAdut;
+     s64 temp = 25000;
Quoted 8 lines

drivers/iio/temperature/mlx90632.c line 446

Quoted 7 lines
drivers/iio/temperature/mlx90632.c new file +7 -0
+     s8 i;
+
+     kTA = (Ea * TENTO3) >> 16LL;
+     kTA0 = (Eb * TENTO3) >> 8LL;
+     TAdut = div64_s64(((ambient - kTA0) * TENTO6), kTA) + 25 * TENTO6;
+
+     for (i = 0; i < 5; ++i) {

comment on why iterations are needed would be good here.

This is described in datasheet (the whole calculation). Will add explanatory comment.

Quoted 133 lines
Quoted 118 lines
drivers/iio/temperature/mlx90632.c new file +118 -0
+             temp = mlx90632_calc_temp_object_iteration(temp, object, TAdut,
+                                                        Fa, Fb, Ga, Ha, Hb,
+                                                        tmp_emi);
+     }
+     return temp;
+}
+
+static int mlx90632_calc_object_dsp105(struct mlx90632_data *data, int *val)
+{
+     s32 ret;
+     s32 Ea, Eb, Fa, Fb, Ga;
+     unsigned int read_tmp;
+     s16 Ha, Hb, Gb, Ka;
+     s16 ambient_new_raw, ambient_old_raw, object_new_raw, object_old_raw;
+     s64 object, ambient;
+
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ea, &Ea);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Eb, &Eb);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fa, &Fa);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fb, &Fb);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ga, &Ga);
+     if (ret < 0)
+             return ret;
+     ret = regmap_read(data->regmap, MLX90632_EE_Ha, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Ha = (s16)read_tmp;
+     ret = regmap_read(data->regmap, MLX90632_EE_Hb, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Hb = (s16)read_tmp;
+     ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Gb = (s16)read_tmp;
+     ret = regmap_read(data->regmap, MLX90632_EE_Ka, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Ka = (s16)read_tmp;
+
+     ret = mlx90632_read_all_channel(data,
+                                     &ambient_new_raw, &ambient_old_raw,
+                                     &object_new_raw, &object_old_raw);
+     if (ret < 0)
+             return ret;
+
+     ambient = mlx90632_preprocess_temp_amb(ambient_new_raw,
+                                            ambient_old_raw, Gb);
+     object = mlx90632_preprocess_temp_obj(object_new_raw,
+                                           object_old_raw,
+                                           ambient_new_raw,
+                                           ambient_old_raw, Ka);
+
+     *val = mlx90632_calc_temp_object(object, ambient, Ea, Eb, Fa, Fb, Ga,
+                                      Ha, Hb, data->emissivity);
+     return 0;
+}
+
+static int mlx90632_calc_ambient_dsp105(struct mlx90632_data *data, int *val)
+{
+     s32 ret;
+     unsigned int read_tmp;
+     s32 PT, PR, PG, PO;
+     s16 Gb;
+     s16 ambient_new_raw, ambient_old_raw;
+
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_R, &PR);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_G, &PG);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_T, &PT);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_O, &PO);
+     if (ret < 0)
+             return ret;
+     ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Gb = (s16)read_tmp;
+
+     ret = mlx90632_read_ambient_raw(data->regmap, &ambient_new_raw,
+                                     &ambient_old_raw);
+     *val = mlx90632_calc_temp_ambient(ambient_new_raw, ambient_old_raw,
+                                       PT, PR, PG, PO, Gb);
+     return ret;
+}
+
+static int mlx90632_read_raw(struct iio_dev *indio_dev,
+                          struct iio_chan_spec const *channel, int *val,
+                          int *val2, long mask)
+{
+     struct mlx90632_data *data = iio_priv(indio_dev);
+     int ret;
+
+     switch (mask) {
+     case IIO_CHAN_INFO_PROCESSED:
+             switch (channel->channel2) {
+             case IIO_MOD_TEMP_AMBIENT:
+                     ret = mlx90632_calc_ambient_dsp105(data, val);
+                     if (ret < 0)
+                             return ret;
+                     return IIO_VAL_INT;
+             case IIO_MOD_TEMP_OBJECT:
+                     ret = mlx90632_calc_object_dsp105(data, val);
+                     if (ret < 0)
+                             return ret;
+                     return IIO_VAL_INT;

drivers/iio/temperature/mlx90632.c line 574

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+             default:
+                     return -EINVAL;
+             }
+     case IIO_CHAN_INFO_CALIBEMISSIVITY:
+             if (data->emissivity == 1000) {
+                     *val = 1;
+                     *val2 = 0;
+             } else {
+                     *val = 0;
+                     *val2 = data->emissivity;

Odd given you are reporting as int + nano
this goes from 1.0 to 0.000000999 in one step?
Seems unlikely.. If it is true then a comment
is needed.

Quoted 3 lines

The write is int + micro but this would still be wrong without a factor of 1000.

In input (write) below I am adding factor of 1000. I do not know if resolution like that is needed, but you never know what they come up with in real life so I rather left some of the breating space.

Quoted 13 lines
Quoted 13 lines
drivers/iio/temperature/mlx90632.c new file +13 -0
+             }
+             return IIO_VAL_INT_PLUS_NANO;
+
+     default:
+             return -EINVAL;
+     }
+}
+
+static int mlx90632_write_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *channel, int val,
+                           int val2, long mask)
+{
+     struct mlx90632_data *data = iio_priv(indio_dev);
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 592

Quoted 5 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+
+     switch (mask) {
+     case IIO_CHAN_INFO_CALIBEMISSIVITY:
+             if (val < 0 || val2 < 0 || val > 1 ||
+                 (val == 1 && val2 != 0))

I'd add a comment describing what this is doing. I think it is checking for 0-1.0 inclusive?

Yes, exactly. In case you set emissivity outside of range it should not change it and return EINVAL.

Quoted 80 lines
Quoted 80 lines
drivers/iio/temperature/mlx90632.c new file +80 -0
+                     return -EINVAL;
+             data->emissivity = val * 1000 + val2 / 1000;
+             return 0;
+     default:
+             return -EINVAL;
+     }
+}
+
+static const struct iio_chan_spec mlx90632_channels[] = {
+     {
+             .type = IIO_TEMP,
+             .modified = 1,
+             .channel2 = IIO_MOD_TEMP_AMBIENT,
+             .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+     },
+     {
+             .type = IIO_TEMP,
+             .modified = 1,
+             .channel2 = IIO_MOD_TEMP_OBJECT,
+             .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+                     BIT(IIO_CHAN_INFO_CALIBEMISSIVITY),
+     },
+};
+
+static const struct iio_info mlx90632_info = {
+     .read_raw = mlx90632_read_raw,
+     .write_raw = mlx90632_write_raw,
+};
+
+#ifdef CONFIG_PM
+static int mlx90632_sleep(struct mlx90632_data *data)
+{
+     dev_dbg(&data->client->dev, "Requesting sleep");
+     return mlx90632_pwr_set_sleep_step(data->regmap);
+}
+
+static int mlx90632_wakeup(struct mlx90632_data *data)
+{
+     dev_dbg(&data->client->dev, "Requesting wake-up");
+     return mlx90632_pwr_continuous(data->regmap);
+}
+#endif
+
+static int mlx90632_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+     struct iio_dev *indio_dev;
+     struct mlx90632_data *mlx90632;
+     struct regmap *regmap;
+     int ret;
+     unsigned int read;
+
+     indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*mlx90632));
+     if (!indio_dev) {
+             dev_err(&client->dev, "Failed to allocate device");
+             return -ENOMEM;
+     }
+
+     regmap = devm_regmap_init_i2c(client, &mlx90632_regmap);
+     if (IS_ERR(regmap)) {
+             ret = PTR_ERR(regmap);
+             dev_err(&client->dev, "Failed to allocate regmap: %d\n", ret);
+             return ret;
+     }
+
+     mlx90632 = iio_priv(indio_dev);
+     i2c_set_clientdata(client, indio_dev);
+     mlx90632->client = client;
+     mlx90632->regmap = regmap;
+
+     mutex_init(&mlx90632->lock);
+     mlx90632_wakeup(mlx90632);
+
+     indio_dev->dev.parent = &client->dev;
+     indio_dev->name = id->name;
+     indio_dev->modes = INDIO_DIRECT_MODE;
+     indio_dev->info = &mlx90632_info;
+     indio_dev->channels = mlx90632_channels;
+     indio_dev->num_channels = ARRAY_SIZE(mlx90632_channels);
+
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 678

Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+     ret = regmap_read(mlx90632->regmap, MLX90632_EE_VERSION, &read);
+     if (ret < 0) {
+             dev_err(&client->dev, "read of version failed: %d\n", ret);
+             return ret;
+     }
+     if (read == (MLX90632_EEPROM_VERSION & MLX90632_ID_MEDICAL)) {

This is odd. Why the bitwise and of what look to be two different things entirely?

If you look at how they are set (high vs low bits) you will see they are complimentary and
prepared exactly for bitwise check. ID_MEDICAL might not be best name, but EEPROM_ID_MEDICAL was just too long. You read 16 bits and that is why lower 8 bits
are in fact EEPROM_VERSION while higher 8 are ID of calibration. Since calculations
are currently dependent on lower 8 bits, I left some of the wiggle space for future.
In case we add another one in future, but I would rather have a strict check for this to
avoid any kind of confusion what is supported.

Quoted 21 lines
Quoted 5 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+             dev_dbg(&client->dev,
+                     "Detected Medical EEPROM calibration %x", read);
+     } else if (read == (MLX90632_EEPROM_VERSION & MLX90632_ID_CONSUMER)) {
+             dev_dbg(&client->dev,
+                     "Detected Consumer EEPROM calibration %x", read);

drivers/iio/temperature/mlx90632.c line 693

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+     } else {
+             dev_err(&client->dev,
+                     "Chip EEPROM version mismatch %x (expected %x)",
+                     read, MLX90632_EEPROM_VERSION);
+             return -EPROTONOSUPPORT;
+     }
+
+     mlx90632->emissivity = 1000;
+
+     return devm_iio_device_register(&client->dev, indio_dev);

Don't use devm version. You are (correctly) manually unwinding this in the remove (as you have pm to deal with after removing the interfaces). This will result in a double free I think... return iio_device_register is the way to go.

Quoted 4 lines

I'm a bit confused that you don't seem to set up runtime pm anywhere... I would assume we would be looking at autosuspend for a device like this but it isn't enabled..

OK, will check how to use iio_device_register instead.

I did not do much of PM on device, so I can't really say. That is why autosuspend is not enabled.

Quoted 42 lines
Quoted 27 lines
drivers/iio/temperature/mlx90632.c new file +27 -0
+}
+
+static int mlx90632_remove(struct i2c_client *client)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(client);
+     struct mlx90632_data *data = iio_priv(indio_dev);
+
+     iio_device_unregister(indio_dev);
+
+     pm_runtime_disable(&client->dev);
+     if (!pm_runtime_status_suspended(&client->dev))
+             mlx90632_sleep(data);
+     pm_runtime_set_suspended(&client->dev);
+
+     return 0;
+}
+
+static const struct i2c_device_id mlx90632_id[] = {
+     { "mlx90632", 0 },
+     { }
+};
+MODULE_DEVICE_TABLE(i2c, mlx90632_id);
+
+static const struct of_device_id mlx90632_of_match[] = {
+     { .compatible = "melexis,mlx90632" },
+     { }
+};

drivers/iio/temperature/mlx90632.c line 730

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+MODULE_DEVICE_TABLE(of, mlx90632_of_match);
+
+#ifdef CONFIG_PM_SLEEP
+static int mlx90632_pm_suspend(struct device *dev)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *data = iio_priv(indio_dev);
+
+     if (pm_runtime_active(dev))
+             return mlx90632_sleep(data);

I'm a little confused as to why, if the device is powered up fully and a suspend comes in we have to do less than we do in runtime pm case.

Quoted 2 lines

Am I missing something?

I think I have mostly tested runtime pm case, so this might have been missed. I did get wrong results if I did not mark regcache as dirty.

I will just remove the whole PM thing to start with and add it up later, OK?

Quoted 77 lines
Quoted 62 lines
drivers/iio/temperature/mlx90632.c new file +62 -0
+
+     return 0;
+}
+
+static int mlx90632_pm_resume(struct device *dev)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *data = iio_priv(indio_dev);
+     int err;
+
+     err = mlx90632_wakeup(data);
+     if (err < 0)
+             return err;
+
+     pm_runtime_disable(dev);
+     pm_runtime_set_active(dev);
+     pm_runtime_enable(dev);
+
+     return 0;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int mlx90632_pm_runtime_suspend(struct device *dev)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *mlx90632 = iio_priv(indio_dev);
+
+     regcache_sync(mlx90632->regmap);
+
+     return mlx90632_sleep(mlx90632);
+}
+
+static int mlx90632_pm_runtime_resume(struct device *dev)
+{
+     s32 ret;
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *mlx90632 = iio_priv(indio_dev);
+
+     regcache_mark_dirty(mlx90632->regmap);
+     regcache_cache_only(mlx90632->regmap, false);
+     ret = regcache_sync(mlx90632->regmap);
+     if (ret < 0) {
+             dev_err(dev, "Failed to sync regmap registers: %d\n", ret);
+             return ret;
+     }
+
+     return mlx90632_wakeup(mlx90632);
+}
+#endif
+
+static const struct dev_pm_ops mlx90632_pm_ops = {
+     SET_SYSTEM_SLEEP_PM_OPS(mlx90632_pm_suspend, mlx90632_pm_resume)
+     SET_RUNTIME_PM_OPS(mlx90632_pm_runtime_suspend,
+                        mlx90632_pm_runtime_resume, NULL)
+};
+
+static struct i2c_driver mlx90632_driver = {
+     .driver = {
+             .name   = "mlx90632",
+             .of_match_table = mlx90632_of_match,
+             .pm     = &mlx90632_pm_ops,

drivers/iio/temperature/mlx90632.c line 802

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+     },
+     .probe = mlx90632_probe,
+     .remove = mlx90632_remove,
+     .id_table = mlx90632_id,
+};
+module_i2c_driver(mlx90632_driver);
+
+MODULE_AUTHOR("Crt Mori <[email protected]>");
+MODULE_DESCRIPTION("Melexis MLX90632 contactless Infra Red temperature sensor driver");
+MODULE_LICENSE("GPL v2");

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#3 lore raw
Quoted 196 lines · On Sat, 2 Dec 2017 21:30:54 +0100 Crt Mori <[email protected]> wrote:

Hi Jonathan,
Definitely did not think there will be so many comments inside, but I expected few of them indeed.

See my replies inside.

Quoted 179 lines · Jonathan Cameron
Quoted 6 lines · On Wed, 29 Nov 2017 23:07:49 +0100 Crt Mori <[email protected]> wrote:

Melexis has just released Infra Red temperature sensor MLX90632 used for contact-less temperature measurement. Driver provides basic functionality for reporting object (and ambient) temperature with support for object emissivity.

Various comments inline.

Quoted 69 lines
---
 MAINTAINERS                        |   7 +
 drivers/iio/temperature/Kconfig    |  12 +
 drivers/iio/temperature/Makefile   |   1 +
 drivers/iio/temperature/mlx90632.c | 802 +++++++++++++++++++++++++++++++++++++
 4 files changed, 822 insertions(+)
 create mode 100644 drivers/iio/temperature/mlx90632.c
MAINTAINERS +7 -0
index 2d3d750b19c0..81aec02b08b8 100644
@@ -8690,6 +8690,13 @@ W:     http://www.melexis.com
 S:   Supported
 F:   drivers/iio/temperature/mlx90614.c
 
+MELEXIS MLX90632 DRIVER
+M:   Crt Mori <[email protected]>
+L:   [email protected]
+W:   http://www.melexis.com
+S:   Supported
+F:   drivers/iio/temperature/mlx90632.c
+
 MELFAS MIP4 TOUCHSCREEN DRIVER
 M:   Sangwon Jee <[email protected]>
 W:   http://www.melfas.com
drivers/iio/temperature/Kconfig +12 -0
index 5378976d6d27..82e4a62745e2 100644
@@ -43,6 +43,18 @@ config MLX90614
        This driver can also be built as a module. If so, the module will
        be called mlx90614.
 
+config MLX90632
+     tristate "MLX90632 contact-less infrared sensor with medical accuracy"
+     depends on I2C
+     select REGMAP_I2C
+     help
+       If you say yes here you get support for the Melexis
+       MLX90632 contact-less infrared sensor with medical accuracy
+       connected with I2C.
+
+       This driver can also be built as a module. If so, the module will
+       be called mlx90632.
+
 config TMP006
      tristate "TMP006 infrared thermopile sensor"
      depends on I2C
drivers/iio/temperature/Makefile +1 -0
index ad1d668de546..44644fe01bc9 100644
@@ -5,6 +5,7 @@
 obj-$(CONFIG_HID_SENSOR_TEMP) += hid-sensor-temperature.o
 obj-$(CONFIG_MAXIM_THERMOCOUPLE) += maxim_thermocouple.o
 obj-$(CONFIG_MLX90614) += mlx90614.o
+obj-$(CONFIG_MLX90632) += mlx90632.o
 obj-$(CONFIG_TMP006) += tmp006.o
 obj-$(CONFIG_TMP007) += tmp007.o
 obj-$(CONFIG_TSYS01) += tsys01.o
drivers/iio/temperature/mlx90632.c new file +2 -0
new file mode 100644
index 000000000000..05c7d943e504
@@ -0,0 +1,802 @@
+/*
+ * mlx90632.c - Melexis MLX90632 contactless IR temperature sensor

drivers/iio/temperature/mlx90632.c line 12

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+ *
+ * Copyright (c) 2017 Melexis <[email protected]>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * Driver for the Melexis MLX90632 I2C 16-bit IR thermopile sensor
+ */
+#include <asm/byteorder.h>  

Don't think this should ever be included in a driver. What do you need it for?

drivers/iio/temperature/mlx90632.c line 23

Quoted 11 lines
drivers/iio/temperature/mlx90632.c new file +11 -0
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/math64.h>
+#include <linux/of.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/unaligned/be_byteshift.h>  

why?

Quoted 72 lines
drivers/iio/temperature/mlx90632.c new file +72 -0
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+/* Memory sections addresses */
+#define MLX90632_ADDR_RAM    0x4000 /* Start address of ram */
+#define MLX90632_ADDR_EEPROM 0x2480 /* Start address of user eeprom */
+
+/* EEPROM addresses - used at startup */
+#define MLX90632_EE_CTRL     0x24d4 /* Control register initial value */
+#define MLX90632_EE_I2C_ADDR 0x24d5 /* I2C address register initial value */
+#define MLX90632_EE_VERSION  0x240b /* EEPROM version reg address */
+#define MLX90632_EE_P_R              0x240c /* P_R calibration register 32bit */
+#define MLX90632_EE_P_G              0x240e /* P_G calibration register 32bit */
+#define MLX90632_EE_P_T              0x2410 /* P_T calibration register 32bit */
+#define MLX90632_EE_P_O              0x2412 /* P_O calibration register 32bit */
+#define MLX90632_EE_Aa               0x2414 /* Aa calibration register 32bit */
+#define MLX90632_EE_Ab               0x2416 /* Ab calibration register 32bit */
+#define MLX90632_EE_Ba               0x2418 /* Ba calibration register 32bit */
+#define MLX90632_EE_Bb               0x241a /* Bb calibration register 32bit */
+#define MLX90632_EE_Ca               0x241c /* Ca calibration register 32bit */
+#define MLX90632_EE_Cb               0x241e /* Cb calibration register 32bit */
+#define MLX90632_EE_Da               0x2420 /* Da calibration register 32bit */
+#define MLX90632_EE_Db               0x2422 /* Db calibration register 32bit */
+#define MLX90632_EE_Ea               0x2424 /* Ea calibration register 32bit */
+#define MLX90632_EE_Eb               0x2426 /* Eb calibration register 32bit */
+#define MLX90632_EE_Fa               0x2428 /* Fa calibration register 32bit */
+#define MLX90632_EE_Fb               0x242a /* Fb calibration register 32bit */
+#define MLX90632_EE_Ga               0x242c /* Ga calibration register 32bit */
+
+#define MLX90632_EE_Gb               0x242e /* Gb calibration register 16bit */
+#define MLX90632_EE_Ka               0x242f /* Ka calibration register 16bit */
+
+#define MLX90632_EE_Ha               0x2481 /* Ha customer calib value reg 16bit */
+#define MLX90632_EE_Hb               0x2482 /* Hb customer calib value reg 16bit */
+
+/* Register addresses - volatile */
+#define MLX90632_REG_I2C_ADDR        0x3000 /* Chip I2C address register */
+
+/* Control register address - volatile */
+#define MLX90632_REG_CONTROL 0x3001 /* Control Register address */
+#define   MLX90632_CFG_PWR_MASK              GENMASK(2, 1) /* PowerMode Mask */
+/* PowerModes statuses */
+#define MLX90632_PWR_STATUS(ctrl_val) (ctrl_val << 1)
+#define MLX90632_PWR_STATUS_HALT MLX90632_PWR_STATUS(0) /* hold */
+#define MLX90632_PWR_STATUS_SLEEP_STEP MLX90632_PWR_STATUS(1) /* sleep step*/
+#define MLX90632_PWR_STATUS_STEP MLX90632_PWR_STATUS(2) /* step */
+#define MLX90632_PWR_STATUS_CONTINUOUS MLX90632_PWR_STATUS(3) /* continuous*/
+
+/* Device status register - volatile */
+#define MLX90632_REG_STATUS  0x3fff /* Device status register */
+#define   MLX90632_STAT_BUSY         BIT(10) /* Device busy indicator */
+#define   MLX90632_STAT_EE_BUSY              BIT(9) /* EEPROM busy indicator */
+#define   MLX90632_STAT_BRST         BIT(8) /* Brown out reset indicator */
+#define   MLX90632_STAT_CYCLE_POS    GENMASK(6, 2) /* Data position */
+#define   MLX90632_STAT_DATA_RDY     BIT(0) /* Data ready indicator */
+
+/* RAM_MEAS address-es for each channel */
+#define MLX90632_RAM_1(meas_num)     (MLX90632_ADDR_RAM + 3 * meas_num)
+#define MLX90632_RAM_2(meas_num)     (MLX90632_ADDR_RAM + 3 * meas_num + 1)
+#define MLX90632_RAM_3(meas_num)     (MLX90632_ADDR_RAM + 3 * meas_num + 2)
+
+/* Magic constants */
+#define MLX90632_EEPROM_VERSION      0xff05 /* EEPROM DSP version for constants */
+#define MLX90632_ID_MEDICAL  0x01ff /* EEPROM Medical device id */
+#define MLX90632_ID_CONSUMER 0x02ff /* EEPROM Consumer device id */
+#define MLX90632_EEPROM_WRITE_KEY 0x554C /* EEPROM write key 0x55 and 0x4c */
+#define MLX90632_RESET_CMD   0x0006 /* Reset sensor (address or global) */
+#define MLX90632_REF_12              12LL /**< ResCtrlRef value of Ch 1 or Ch 2 */
+#define MLX90632_REF_3               12LL /**< ResCtrlRef value of Channel 3 */
+
+#define TENTO3                       1000LL
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 101

Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+#define TENTO4                       10000LL
+#define TENTO5                       100000LL
+#define TENTO6                       1000000LL
+#define TENTO7                       10000000LL
+#define TENTO10                      10000000000LL
+#define TENTO12                      1000000000000LL  

Umm. The numbers describe the constants rather better than the defines ;) Just use the numbers if you need them!

Quoted 2 lines

This is way shorter (line length) and more readable in my opinion. Also writing 12 times 0 is error prone :D

Needs care but I really don't like these constants.

Quoted 73 lines
Quoted 63 lines
Quoted 63 lines
drivers/iio/temperature/mlx90632.c new file +62 -0
+
+struct mlx90632_data {
+     struct i2c_client *client;
+     struct mutex lock; /* Multiple reads for single measurement */
+     struct regmap *regmap;
+     u16 emissivity;
+};
+
+static const struct regmap_range mlx90632_volatile_reg_range[] = {
+     regmap_reg_range(MLX90632_REG_CONTROL, MLX90632_REG_I2C_ADDR),
+     regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
+     regmap_reg_range(MLX90632_RAM_1(0),
+                      MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_volatile_regs_tbl = {
+     .yes_ranges = mlx90632_volatile_reg_range,
+     .n_yes_ranges = ARRAY_SIZE(mlx90632_volatile_reg_range),
+};
+
+static const struct regmap_range mlx90632_read_reg_range[] = {
+     regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
+     regmap_reg_range(MLX90632_EE_CTRL, MLX90632_EE_I2C_ADDR),
+     regmap_reg_range(MLX90632_EE_Ha, MLX90632_EE_Hb),
+     regmap_reg_range(MLX90632_REG_CONTROL, MLX90632_REG_I2C_ADDR),
+     regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
+     regmap_reg_range(MLX90632_RAM_1(0),
+                      MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_readable_regs_tbl = {
+     .yes_ranges = mlx90632_read_reg_range,
+     .n_yes_ranges = ARRAY_SIZE(mlx90632_read_reg_range),
+};
+
+static const struct regmap_range mlx90632_no_write_reg_range[] = {
+     regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
+     regmap_reg_range(MLX90632_RAM_1(0),
+                      MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_writeable_regs_tbl = {
+     .no_ranges = mlx90632_no_write_reg_range,
+     .n_no_ranges = ARRAY_SIZE(mlx90632_no_write_reg_range),
+};
+
+static const struct regmap_config mlx90632_regmap = {
+     .reg_bits = 16,
+     .val_bits = 16,
+
+     .volatile_table = &mlx90632_volatile_regs_tbl,
+     .rd_table = &mlx90632_readable_regs_tbl,
+     .wr_table = &mlx90632_writeable_regs_tbl,
+
+     .use_single_rw = true,
+     .reg_format_endian = REGMAP_ENDIAN_BIG,
+     .val_format_endian = REGMAP_ENDIAN_BIG,
+     .cache_type = REGCACHE_RBTREE,
+};
+
+static u64 mlx90632_int_sqrt(u64 x)
+{
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 167

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+     u64 b, m, y = 0;
+
+     if (BITS_PER_LONG != 32)
+             return int_sqrt(x);  

needs a comment on why...
Ideally propose a standard 64 bit routine if one is needed for 32 bit machines.

Quoted 7 lines

Problem is that int_sqrt is not strongly typed. That means 64 bit number gets truncated to 32bit on 32bit machine as you mentioned and that caused quite many headaches in my testing (worked on mobile phone, but not on beaglebone black). This solution is just stronger typing of int_sqrt function.

If you think I should put it onto math.h as a patch I can try it.

Sure, let's see if that goes anywhere. Seems the right approach to me.

Quoted 104 lines
Quoted 37 lines
Quoted 37 lines
drivers/iio/temperature/mlx90632.c new file +36 -0
+
+     if (x <= 1)
+             return x;
+
+     m = 1ULL << (64 - 2);
+     while (m != 0) {
+             b = y + m;
+             y >>= 1;
+
+             if (x >= b) {
+                     x -= b;
+                     y += m;
+             }
+             m >>= 2;
+     }
+     return y;
+}
+
+static s32 mlx90632_pwr_set_sleep_step(struct regmap *regmap)
+{
+     return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+                               MLX90632_CFG_PWR_MASK,
+                               MLX90632_PWR_STATUS_SLEEP_STEP);
+}
+
+static s32 mlx90632_pwr_set_step(struct regmap *regmap)
+{
+     return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+                               MLX90632_CFG_PWR_MASK,
+                               MLX90632_PWR_STATUS_STEP);
+}
+
+static s32 mlx90632_pwr_continuous(struct regmap *regmap)
+{
+     return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+                               MLX90632_CFG_PWR_MASK,
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 207

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+                               MLX90632_PWR_STATUS_CONTINUOUS);
+}
+
+static int mlx90632_start_measurement(struct mlx90632_data *data)  

Looks superficially to me like this is actually waiting for a reading to complete rather than just starting it? If so change the name to reflect that.

ok

Quoted 20 lines
Quoted 20 lines
drivers/iio/temperature/mlx90632.c new file +20 -0
+{
+     int ret, tries = 100;
+     unsigned int reg_status;
+
+     ret = regmap_update_bits(data->regmap, MLX90632_REG_STATUS,
+                              MLX90632_STAT_DATA_RDY, 0);
+     if (ret < 0)
+             return ret;
+
+     while (tries-- > 0) {
+             ret = regmap_read(data->regmap, MLX90632_REG_STATUS,
+                               &reg_status);
+             if (ret < 0)
+                     return ret;
+             if (reg_status & MLX90632_STAT_DATA_RDY)
+                     break;
+             usleep_range(10000, 11000);
+     }
+
+     if (tries < 0) {
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 232

Quoted 5 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+             dev_err(&data->client->dev, "data not ready");
+             return -ETIMEDOUT;
+     }
+
+     return (reg_status & MLX90632_STAT_CYCLE_POS) >> 2;  

This is a non obvious return value so I would suggest adding some documentation to say what is going on here..

Yes, it is indeed.

Quoted 8 lines

drivers/iio/temperature/mlx90632.c line 236

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+}
+
+static int mlx9032_channel_new_select(int ret, uint8_t *channel_new,
+                                   uint8_t *channel_old)  

don't use ret as a name for a variable being passed in. Rather confusing!

OK. I think I should just copy setting of channel_old and new in the only spot it is used.

Quoted 11 lines
Quoted 11 lines
drivers/iio/temperature/mlx90632.c new file +11 -0
+{
+     if (ret == 1) {
+             *channel_new = 1;
+             *channel_old = 2;
+     } else if (ret == 2) {
+             *channel_new = 2;
+             *channel_old = 1;
+     } else {
+             return ret;
+     }
+     return 0;  
Quoted 6 lines
Quoted 2 lines

Can't get here...

Not true. You get here in every example other than else where channel_new and channel_old are successfully set. but I agree there is a bug in case ret=0 when it will return 0, but it will not set channels.

Ah good point, I missed that. I would do it as a switch with direct returns.

Quoted 118 lines
Quoted 93 lines
Quoted 70 lines
drivers/iio/temperature/mlx90632.c new file +69 -0
+}
+
+static int mlx90632_read_ambient_raw(struct regmap *regmap,
+                                  s16 *ambient_new_raw, s16 *ambient_old_raw)
+{
+     int ret;
+     unsigned int read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_3(1), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *ambient_new_raw = (s16)read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_3(2), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *ambient_old_raw = (s16)read_tmp;
+
+     return ret;
+}
+
+static int mlx90632_read_object_raw(struct regmap *regmap,
+                                 int start_measurement_ret,
+                                 s16 *object_new_raw, s16 *object_old_raw)
+{
+     int ret;
+     unsigned int read_tmp;
+     s16 read;
+     u8 channel = 0;
+     u8 channel_old = 0;
+
+     ret = mlx90632_channel_new_select(start_measurement_ret, &channel,
+                                       &channel_old);
+     if (ret != 0)
+             return ret;
+
+     ret = regmap_read(regmap, MLX90632_RAM_2(channel), &read_tmp);
+     if (ret < 0)
+             return ret;
+
+     read = (s16)read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_1(channel), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *object_new_raw = (read + (s16)read_tmp) / 2;
+
+     ret = regmap_read(regmap, MLX90632_RAM_2(channel_old), &read_tmp);
+     if (ret < 0)
+             return ret;
+     read = (s16)read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_1(channel_old), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *object_old_raw = (read + (s16)read_tmp) / 2;
+
+     return ret;
+}
+
+static int mlx90632_read_all_channel(struct mlx90632_data *data,
+                                  s16 *ambient_new_raw, s16 *ambient_old_raw,
+                                  s16 *object_new_raw, s16 *object_old_raw)
+{
+     s32 ret, tm_ret;
+
+     mutex_lock(&data->lock);
+     tm_ret = mlx90632_start_measurement(data);
+     if (tm_ret >= 0) {

drivers/iio/temperature/mlx90632.c line 326

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+             ret = mlx90632_read_ambient_raw(data->regmap, ambient_new_raw,
+                                             ambient_old_raw);
+             if (ret >= 0) {
+                     ret = mlx90632_read_object_raw(data->regmap, tm_ret,
+                                                    object_new_raw,
+                                                    object_old_raw);
+             }
+     } else {
+             ret = tm_ret;
+     }  

Use something cleaner like

        mutex_lock(&data->lock);
        ret = mlx90632_start_measurement(data);
        if (ret < 0)
                goto unlock;
        ret = mlx90632_read_ambient_raw(data->regmap, ambient_new_raw,
                                        ambient_old_raw);
        if (ret < 0)
                goto unlock;

        ret = mlx90632_read_object_raw(data->regmap, tm_ret,
                                       object_new_raw,
                                       object_old_raw);
Quoted 1 line

unlock:

Ok sorry, professional deformation (goto).

Quoted 21 lines
Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+     mutex_unlock(&data->lock);
+     return ret;
+}
+
+static int mlx90632_read_ee_register(struct regmap *regmap, u16 reg_lsb,
+                                  s32 *reg_value)

drivers/iio/temperature/mlx90632.c line 342

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+{
+     s32 ret;
+     unsigned int read;
+     __le32 value;
+
+     ret = regmap_read(regmap, reg_lsb, &read);
+     if (ret < 0)
+             return ret;
+
+     value = cpu_to_le32(read);  

Why would you be converting to le32 to then do
calculations in here using it at cpu endianness?
(guessing you want le32_to_cpu..)

Quoted 8 lines
Quoted 3 lines

hmm isn't any relevant endian conversion wrapped up in regmap anyway?

Regmap reads 16 bit values, but some values are 32 bit. To avoid CPU endianess affecting this, I am putting it to known time and shift values. This way I ensured it is working on any CPU. le32_to_cpu is in return value.

I'm far from convinced this is a good idea. I would ensure all values are in cpu endianness before combining them based on the read order (which is endian independant)

Quoted 242 lines
Quoted 97 lines
Quoted 97 lines
drivers/iio/temperature/mlx90632.c new file +97 -0
+
+     ret = regmap_read(regmap, reg_lsb + 1, &read);
+     if (ret < 0)
+             return ret;
+
+     value = (cpu_to_le32(read) << 16) | (value & 0xffff);
+
+     *reg_value = le32_to_cpu(value);
+     return 0;
+}
+
+static s64 mlx90632_preprocess_temp_amb(s16 ambient_new_raw,
+                                     s16 ambient_old_raw, s16 Gb)
+{
+     s64 VR_Ta, kGb, tmp;
+
+     kGb = ((s64)Gb * TENTO3) >> 10ULL;
+     VR_Ta = (s64)ambient_old_raw * TENTO6 +
+             kGb * div64_s64(((s64)ambient_new_raw * TENTO3),
+                     (MLX90632_REF_3));
+     tmp = div64_s64(
+                      div64_s64(((s64)ambient_new_raw * TENTO12),
+                                (MLX90632_REF_3)), VR_Ta);
+     return div64_s64(tmp << 19ULL, TENTO3);
+}
+
+static s64 mlx90632_preprocess_temp_obj(s16 object_new_raw, s16 object_old_raw,
+                                     s16 ambient_new_raw,
+                                     s16 ambient_old_raw, s16 Ka)
+{
+     s64 VR_IR, kKa, tmp;
+
+     kKa = ((s64)Ka * TENTO3) >> 10ULL;
+     VR_IR = (s64)ambient_old_raw * TENTO6 +
+             kKa * div64_s64(((s64)ambient_new_raw * TENTO3),
+                     (MLX90632_REF_3));
+     tmp = div64_s64(
+                     div64_s64(((s64)((object_new_raw + object_old_raw) / 2)
+                                * TENTO12), (MLX90632_REF_12)), VR_IR);
+     return div64_s64(tmp << 19ULL), TENTO3);
+}
+
+static s32 mlx90632_calc_temp_ambient(s16 ambient_new_raw, s16 ambient_old_raw,
+                                   s32 P_T, s32 P_R, s32 P_G, s32 P_O,
+                                   s16 Gb)
+{
+     s64 Asub, Bsub, Ablock, Bblock, Cblock, AMB, sum;
+
+     AMB = mlx90632_preprocess_temp_amb(ambient_new_raw, ambient_old_raw,
+                                        Gb);
+     Asub = ((s64)P_T * TENTO10) >> 44ULL;
+     Bsub = AMB - (((s64)P_R * TENTO3) >> 8ULL);
+     Ablock = Asub * (Bsub * Bsub);
+     Bblock = (div64_s64(Bsub * TENTO7, P_G)) << 20ULL;
+     Cblock = ((s64)P_O * TENTO10) >> 8ULL;
+
+     sum = div64_s64(Ablock, TENTO6) + Bblock + Cblock;
+
+     return div64_s64(sum, TENTO7);
+}
+
+static s32 mlx90632_calc_temp_object_iteration(s32 prev_object_temp, s64 object,
+                                            s64 TAdut, s32 Fa, s32 Fb,
+                                            s32 Ga, s16 Ha, s16 Hb,
+                                            u16 emissivity)
+{
+     s64 calcedKsTO, calcedKsTA, ir_Alpha, TAdut4, Alpha_corr;
+     s64 Ha_customer, Hb_customer;
+
+     Ha_customer = ((s64)Ha * TENTO6) >> 14ULL;
+     Hb_customer = ((s64)Hb * 100) >> 10ULL;
+
+     calcedKsTO = ((s64)((s64)Ga * (prev_object_temp - 25 * TENTO3)
+                          * TENTO3)) >> 36LL;
+     calcedKsTA = ((s64)(Fb * (TAdut - 25 * TENTO6))) >> 36LL;
+     Alpha_corr = div64_s64((((s64)(Fa * TENTO10) >> 46LL) * Ha_customer),
+                            TENTO3);
+     Alpha_corr *= ((s64)(1 * TENTO6 + calcedKsTO + calcedKsTA));
+     Alpha_corr = emissivity * div64_s64(Alpha_corr, TENTO5);
+     Alpha_corr = div64_s64(Alpha_corr, TENTO3);
+     ir_Alpha = div64_s64((s64)object * TENTO7, Alpha_corr);
+     TAdut4 = (div64_s64(TAdut, TENTO4) + 27315) *
+             (div64_s64(TAdut, TENTO4) + 27315) *
+             (div64_s64(TAdut, TENTO4)  + 27315) *
+             (div64_s64(TAdut, TENTO4) + 27315);
+
+     return (mlx90632_int_sqrt(
+                      mlx90632_int_sqrt(ir_Alpha * TENTO12 + TAdut4)
+                     ) - 27315 - Hb_customer) * 10;
+}
+
+static s32 mlx90632_calc_temp_object(s64 object, s64 ambient, s32 Ea, s32 Eb,
+                                  s32 Fa, s32 Fb, s32 Ga, s16 Ha, s16 Hb,
+                                  u16 tmp_emi)
+{
+     s64 kTA, kTA0, TAdut;
+     s64 temp = 25000;
Quoted 8 lines

drivers/iio/temperature/mlx90632.c line 446

Quoted 7 lines
drivers/iio/temperature/mlx90632.c new file +7 -0
+     s8 i;
+
+     kTA = (Ea * TENTO3) >> 16LL;
+     kTA0 = (Eb * TENTO3) >> 8LL;
+     TAdut = div64_s64(((ambient - kTA0) * TENTO6), kTA) + 25 * TENTO6;
+
+     for (i = 0; i < 5; ++i) {  

comment on why iterations are needed would be good here.

This is described in datasheet (the whole calculation). Will add explanatory comment.

Quoted 133 lines
Quoted 118 lines
drivers/iio/temperature/mlx90632.c new file +118 -0
+             temp = mlx90632_calc_temp_object_iteration(temp, object, TAdut,
+                                                        Fa, Fb, Ga, Ha, Hb,
+                                                        tmp_emi);
+     }
+     return temp;
+}
+
+static int mlx90632_calc_object_dsp105(struct mlx90632_data *data, int *val)
+{
+     s32 ret;
+     s32 Ea, Eb, Fa, Fb, Ga;
+     unsigned int read_tmp;
+     s16 Ha, Hb, Gb, Ka;
+     s16 ambient_new_raw, ambient_old_raw, object_new_raw, object_old_raw;
+     s64 object, ambient;
+
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ea, &Ea);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Eb, &Eb);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fa, &Fa);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fb, &Fb);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ga, &Ga);
+     if (ret < 0)
+             return ret;
+     ret = regmap_read(data->regmap, MLX90632_EE_Ha, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Ha = (s16)read_tmp;
+     ret = regmap_read(data->regmap, MLX90632_EE_Hb, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Hb = (s16)read_tmp;
+     ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Gb = (s16)read_tmp;
+     ret = regmap_read(data->regmap, MLX90632_EE_Ka, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Ka = (s16)read_tmp;
+
+     ret = mlx90632_read_all_channel(data,
+                                     &ambient_new_raw, &ambient_old_raw,
+                                     &object_new_raw, &object_old_raw);
+     if (ret < 0)
+             return ret;
+
+     ambient = mlx90632_preprocess_temp_amb(ambient_new_raw,
+                                            ambient_old_raw, Gb);
+     object = mlx90632_preprocess_temp_obj(object_new_raw,
+                                           object_old_raw,
+                                           ambient_new_raw,
+                                           ambient_old_raw, Ka);
+
+     *val = mlx90632_calc_temp_object(object, ambient, Ea, Eb, Fa, Fb, Ga,
+                                      Ha, Hb, data->emissivity);
+     return 0;
+}
+
+static int mlx90632_calc_ambient_dsp105(struct mlx90632_data *data, int *val)
+{
+     s32 ret;
+     unsigned int read_tmp;
+     s32 PT, PR, PG, PO;
+     s16 Gb;
+     s16 ambient_new_raw, ambient_old_raw;
+
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_R, &PR);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_G, &PG);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_T, &PT);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_O, &PO);
+     if (ret < 0)
+             return ret;
+     ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Gb = (s16)read_tmp;
+
+     ret = mlx90632_read_ambient_raw(data->regmap, &ambient_new_raw,
+                                     &ambient_old_raw);
+     *val = mlx90632_calc_temp_ambient(ambient_new_raw, ambient_old_raw,
+                                       PT, PR, PG, PO, Gb);
+     return ret;
+}
+
+static int mlx90632_read_raw(struct iio_dev *indio_dev,
+                          struct iio_chan_spec const *channel, int *val,
+                          int *val2, long mask)
+{
+     struct mlx90632_data *data = iio_priv(indio_dev);
+     int ret;
+
+     switch (mask) {
+     case IIO_CHAN_INFO_PROCESSED:
+             switch (channel->channel2) {
+             case IIO_MOD_TEMP_AMBIENT:
+                     ret = mlx90632_calc_ambient_dsp105(data, val);
+                     if (ret < 0)
+                             return ret;
+                     return IIO_VAL_INT;
+             case IIO_MOD_TEMP_OBJECT:
+                     ret = mlx90632_calc_object_dsp105(data, val);
+                     if (ret < 0)
+                             return ret;
+                     return IIO_VAL_INT;

drivers/iio/temperature/mlx90632.c line 574

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+             default:
+                     return -EINVAL;
+             }
+     case IIO_CHAN_INFO_CALIBEMISSIVITY:
+             if (data->emissivity == 1000) {
+                     *val = 1;
+                     *val2 = 0;
+             } else {
+                     *val = 0;
+                     *val2 = data->emissivity;  

Odd given you are reporting as int + nano
this goes from 1.0 to 0.000000999 in one step?
Seems unlikely.. If it is true then a comment
is needed.

Quoted 8 lines
Quoted 3 lines

The write is int + micro but this would still be wrong without a factor of 1000.

In input (write) below I am adding factor of 1000. I do not know if resolution like that is needed, but you never know what they come up with in real life so I rather left some of the breating space.

The above still doesn't make much sense unless your range is disjoint 0-0.000000999, 1.0 which would be surprising and also doesn't correspond to the write.

Quoted 117 lines
Quoted 14 lines
Quoted 14 lines
drivers/iio/temperature/mlx90632.c new file +13 -0
+             }
+             return IIO_VAL_INT_PLUS_NANO;
+
+     default:
+             return -EINVAL;
+     }
+}
+
+static int mlx90632_write_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *channel, int val,
+                           int val2, long mask)
+{
+     struct mlx90632_data *data = iio_priv(indio_dev);
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 592

Quoted 5 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+
+     switch (mask) {
+     case IIO_CHAN_INFO_CALIBEMISSIVITY:
+             if (val < 0 || val2 < 0 || val > 1 ||
+                 (val == 1 && val2 != 0))  

I'd add a comment describing what this is doing. I think it is checking for 0-1.0 inclusive?

Yes, exactly. In case you set emissivity outside of range it should not change it and return EINVAL.

Quoted 80 lines
Quoted 80 lines
drivers/iio/temperature/mlx90632.c new file +80 -0
+                     return -EINVAL;
+             data->emissivity = val * 1000 + val2 / 1000;
+             return 0;
+     default:
+             return -EINVAL;
+     }
+}
+
+static const struct iio_chan_spec mlx90632_channels[] = {
+     {
+             .type = IIO_TEMP,
+             .modified = 1,
+             .channel2 = IIO_MOD_TEMP_AMBIENT,
+             .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+     },
+     {
+             .type = IIO_TEMP,
+             .modified = 1,
+             .channel2 = IIO_MOD_TEMP_OBJECT,
+             .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+                     BIT(IIO_CHAN_INFO_CALIBEMISSIVITY),
+     },
+};
+
+static const struct iio_info mlx90632_info = {
+     .read_raw = mlx90632_read_raw,
+     .write_raw = mlx90632_write_raw,
+};
+
+#ifdef CONFIG_PM
+static int mlx90632_sleep(struct mlx90632_data *data)
+{
+     dev_dbg(&data->client->dev, "Requesting sleep");
+     return mlx90632_pwr_set_sleep_step(data->regmap);
+}
+
+static int mlx90632_wakeup(struct mlx90632_data *data)
+{
+     dev_dbg(&data->client->dev, "Requesting wake-up");
+     return mlx90632_pwr_continuous(data->regmap);
+}
+#endif
+
+static int mlx90632_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+     struct iio_dev *indio_dev;
+     struct mlx90632_data *mlx90632;
+     struct regmap *regmap;
+     int ret;
+     unsigned int read;
+
+     indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*mlx90632));
+     if (!indio_dev) {
+             dev_err(&client->dev, "Failed to allocate device");
+             return -ENOMEM;
+     }
+
+     regmap = devm_regmap_init_i2c(client, &mlx90632_regmap);
+     if (IS_ERR(regmap)) {
+             ret = PTR_ERR(regmap);
+             dev_err(&client->dev, "Failed to allocate regmap: %d\n", ret);
+             return ret;
+     }
+
+     mlx90632 = iio_priv(indio_dev);
+     i2c_set_clientdata(client, indio_dev);
+     mlx90632->client = client;
+     mlx90632->regmap = regmap;
+
+     mutex_init(&mlx90632->lock);
+     mlx90632_wakeup(mlx90632);
+
+     indio_dev->dev.parent = &client->dev;
+     indio_dev->name = id->name;
+     indio_dev->modes = INDIO_DIRECT_MODE;
+     indio_dev->info = &mlx90632_info;
+     indio_dev->channels = mlx90632_channels;
+     indio_dev->num_channels = ARRAY_SIZE(mlx90632_channels);
+
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 678

Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+     ret = regmap_read(mlx90632->regmap, MLX90632_EE_VERSION, &read);
+     if (ret < 0) {
+             dev_err(&client->dev, "read of version failed: %d\n", ret);
+             return ret;
+     }
+     if (read == (MLX90632_EEPROM_VERSION & MLX90632_ID_MEDICAL)) {  

This is odd. Why the bitwise and of what look to be two different things entirely?

Quoted 12 lines

If you look at how they are set (high vs low bits) you will see they are complimentary and
prepared exactly for bitwise check. ID_MEDICAL might not be best name, but EEPROM_ID_MEDICAL was just too long. You read 16 bits and that is why lower 8 bits
are in fact EEPROM_VERSION while higher 8 are ID of calibration. Since calculations
are currently dependent on lower 8 bits, I left some of the wiggle space for future.
In case we add another one in future, but I would rather have a strict check for this to
avoid any kind of confusion what is supported.

Surely should be | then?

read == (0xff05 & 0x01ff)

read == (0x105)
So only 3 bits of overlap?

Definitely needs a comment to explain this int the code.

Quoted 27 lines
Quoted 22 lines
Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+             dev_dbg(&client->dev,
+                     "Detected Medical EEPROM calibration %x", read);
+     } else if (read == (MLX90632_EEPROM_VERSION & MLX90632_ID_CONSUMER)) {
+             dev_dbg(&client->dev,
+                     "Detected Consumer EEPROM calibration %x", read);

drivers/iio/temperature/mlx90632.c line 693

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+     } else {
+             dev_err(&client->dev,
+                     "Chip EEPROM version mismatch %x (expected %x)",
+                     read, MLX90632_EEPROM_VERSION);
+             return -EPROTONOSUPPORT;
+     }
+
+     mlx90632->emissivity = 1000;
+
+     return devm_iio_device_register(&client->dev, indio_dev);  

Don't use devm version. You are (correctly) manually unwinding this in the remove (as you have pm to deal with after removing the interfaces). This will result in a double free I think... return iio_device_register is the way to go.

Quoted 4 lines

I'm a bit confused that you don't seem to set up runtime pm anywhere... I would assume we would be looking at autosuspend for a device like this but it isn't enabled..

Quoted 4 lines

OK, will check how to use iio_device_register instead.

I did not do much of PM on device, so I can't really say. That is why autosuspend is not enabled.

If you are dropping the PM for now, then devm_iio_device_register is fine, just drop the remove function entirely as it won't need to do anything.

Quoted 43 lines
Quoted 43 lines
Quoted 28 lines
drivers/iio/temperature/mlx90632.c new file +27 -0
+}
+
+static int mlx90632_remove(struct i2c_client *client)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(client);
+     struct mlx90632_data *data = iio_priv(indio_dev);
+
+     iio_device_unregister(indio_dev);
+
+     pm_runtime_disable(&client->dev);
+     if (!pm_runtime_status_suspended(&client->dev))
+             mlx90632_sleep(data);
+     pm_runtime_set_suspended(&client->dev);
+
+     return 0;
+}
+
+static const struct i2c_device_id mlx90632_id[] = {
+     { "mlx90632", 0 },
+     { }
+};
+MODULE_DEVICE_TABLE(i2c, mlx90632_id);
+
+static const struct of_device_id mlx90632_of_match[] = {
+     { .compatible = "melexis,mlx90632" },
+     { }
+};

drivers/iio/temperature/mlx90632.c line 730

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+MODULE_DEVICE_TABLE(of, mlx90632_of_match);
+
+#ifdef CONFIG_PM_SLEEP
+static int mlx90632_pm_suspend(struct device *dev)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *data = iio_priv(indio_dev);
+
+     if (pm_runtime_active(dev))
+             return mlx90632_sleep(data);  

I'm a little confused as to why, if the device is powered up fully and a suspend comes in we have to do less than we do in runtime pm case.

Quoted 7 lines
Quoted 2 lines

Am I missing something?

I think I have mostly tested runtime pm case, so this might have been missed. I did get wrong results if I did not mark regcache as dirty.

I will just remove the whole PM thing to start with and add it up later, OK?

Makes sense.

Quoted 82 lines
Quoted 70 lines
Quoted 70 lines
drivers/iio/temperature/mlx90632.c new file +69 -0
+
+     return 0;
+}
+
+static int mlx90632_pm_resume(struct device *dev)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *data = iio_priv(indio_dev);
+     int err;
+
+     err = mlx90632_wakeup(data);
+     if (err < 0)
+             return err;
+
+     pm_runtime_disable(dev);
+     pm_runtime_set_active(dev);
+     pm_runtime_enable(dev);
+
+     return 0;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int mlx90632_pm_runtime_suspend(struct device *dev)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *mlx90632 = iio_priv(indio_dev);
+
+     regcache_sync(mlx90632->regmap);
+
+     return mlx90632_sleep(mlx90632);
+}
+
+static int mlx90632_pm_runtime_resume(struct device *dev)
+{
+     s32 ret;
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *mlx90632 = iio_priv(indio_dev);
+
+     regcache_mark_dirty(mlx90632->regmap);
+     regcache_cache_only(mlx90632->regmap, false);
+     ret = regcache_sync(mlx90632->regmap);
+     if (ret < 0) {
+             dev_err(dev, "Failed to sync regmap registers: %d\n", ret);
+             return ret;
+     }
+
+     return mlx90632_wakeup(mlx90632);
+}
+#endif
+
+static const struct dev_pm_ops mlx90632_pm_ops = {
+     SET_SYSTEM_SLEEP_PM_OPS(mlx90632_pm_suspend, mlx90632_pm_resume)
+     SET_RUNTIME_PM_OPS(mlx90632_pm_runtime_suspend,
+                        mlx90632_pm_runtime_resume, NULL)
+};
+
+static struct i2c_driver mlx90632_driver = {
+     .driver = {
+             .name   = "mlx90632",
+             .of_match_table = mlx90632_of_match,
+             .pm     = &mlx90632_pm_ops,
+     },
+     .probe = mlx90632_probe,
+     .remove = mlx90632_remove,
+     .id_table = mlx90632_id,
+};
+module_i2c_driver(mlx90632_driver);
+
Quoted 8 lines

drivers/iio/temperature/mlx90632.c line 802

Quoted 3 lines
drivers/iio/temperature/mlx90632.c new file +3 -0
+MODULE_AUTHOR("Crt Mori <[email protected]>");
+MODULE_DESCRIPTION("Melexis MLX90632 contactless Infra Red temperature sensor driver");
+MODULE_LICENSE("GPL v2");  

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author maintainer
#4 lore raw

Hi Jonathan,
I already sent v2 of the driver with some of your comments in. Will fix remainder in v3 - I am
meanwhile also interested what responses I will get with including into int_sqrt().

Thanks for comments.

Best regards,
Crt

Quoted 391 lines · Jonathan Cameron
Quoted 196 lines · On Sat, 2 Dec 2017 21:30:54 +0100 Crt Mori <[email protected]> wrote:

Hi Jonathan,
Definitely did not think there will be so many comments inside, but I expected few of them indeed.

See my replies inside.

Quoted 179 lines · Jonathan Cameron
Quoted 6 lines · On Wed, 29 Nov 2017 23:07:49 +0100 Crt Mori <[email protected]> wrote:

Melexis has just released Infra Red temperature sensor MLX90632 used for contact-less temperature measurement. Driver provides basic functionality for reporting object (and ambient) temperature with support for object emissivity.

Various comments inline.

Quoted 69 lines
---
 MAINTAINERS                        |   7 +
 drivers/iio/temperature/Kconfig    |  12 +
 drivers/iio/temperature/Makefile   |   1 +
 drivers/iio/temperature/mlx90632.c | 802 +++++++++++++++++++++++++++++++++++++
 4 files changed, 822 insertions(+)
 create mode 100644 drivers/iio/temperature/mlx90632.c
MAINTAINERS +7 -0
index 2d3d750b19c0..81aec02b08b8 100644
@@ -8690,6 +8690,13 @@ W:     http://www.melexis.com
 S:   Supported
 F:   drivers/iio/temperature/mlx90614.c
 
+MELEXIS MLX90632 DRIVER
+M:   Crt Mori <[email protected]>
+L:   [email protected]
+W:   http://www.melexis.com
+S:   Supported
+F:   drivers/iio/temperature/mlx90632.c
+
 MELFAS MIP4 TOUCHSCREEN DRIVER
 M:   Sangwon Jee <[email protected]>
 W:   http://www.melfas.com
drivers/iio/temperature/Kconfig +12 -0
index 5378976d6d27..82e4a62745e2 100644
@@ -43,6 +43,18 @@ config MLX90614
        This driver can also be built as a module. If so, the module will
        be called mlx90614.
 
+config MLX90632
+     tristate "MLX90632 contact-less infrared sensor with medical accuracy"
+     depends on I2C
+     select REGMAP_I2C
+     help
+       If you say yes here you get support for the Melexis
+       MLX90632 contact-less infrared sensor with medical accuracy
+       connected with I2C.
+
+       This driver can also be built as a module. If so, the module will
+       be called mlx90632.
+
 config TMP006
      tristate "TMP006 infrared thermopile sensor"
      depends on I2C
drivers/iio/temperature/Makefile +1 -0
index ad1d668de546..44644fe01bc9 100644
@@ -5,6 +5,7 @@
 obj-$(CONFIG_HID_SENSOR_TEMP) += hid-sensor-temperature.o
 obj-$(CONFIG_MAXIM_THERMOCOUPLE) += maxim_thermocouple.o
 obj-$(CONFIG_MLX90614) += mlx90614.o
+obj-$(CONFIG_MLX90632) += mlx90632.o
 obj-$(CONFIG_TMP006) += tmp006.o
 obj-$(CONFIG_TMP007) += tmp007.o
 obj-$(CONFIG_TSYS01) += tsys01.o
drivers/iio/temperature/mlx90632.c new file +2 -0
new file mode 100644
index 000000000000..05c7d943e504
@@ -0,0 +1,802 @@
+/*
+ * mlx90632.c - Melexis MLX90632 contactless IR temperature sensor

drivers/iio/temperature/mlx90632.c line 12

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+ *
+ * Copyright (c) 2017 Melexis <[email protected]>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * Driver for the Melexis MLX90632 I2C 16-bit IR thermopile sensor
+ */
+#include <asm/byteorder.h>

Don't think this should ever be included in a driver. What do you need it for?

drivers/iio/temperature/mlx90632.c line 23

Quoted 11 lines
drivers/iio/temperature/mlx90632.c new file +11 -0
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/math64.h>
+#include <linux/of.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/unaligned/be_byteshift.h>

why?

Quoted 72 lines
drivers/iio/temperature/mlx90632.c new file +72 -0
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+/* Memory sections addresses */
+#define MLX90632_ADDR_RAM    0x4000 /* Start address of ram */
+#define MLX90632_ADDR_EEPROM 0x2480 /* Start address of user eeprom */
+
+/* EEPROM addresses - used at startup */
+#define MLX90632_EE_CTRL     0x24d4 /* Control register initial value */
+#define MLX90632_EE_I2C_ADDR 0x24d5 /* I2C address register initial value */
+#define MLX90632_EE_VERSION  0x240b /* EEPROM version reg address */
+#define MLX90632_EE_P_R              0x240c /* P_R calibration register 32bit */
+#define MLX90632_EE_P_G              0x240e /* P_G calibration register 32bit */
+#define MLX90632_EE_P_T              0x2410 /* P_T calibration register 32bit */
+#define MLX90632_EE_P_O              0x2412 /* P_O calibration register 32bit */
+#define MLX90632_EE_Aa               0x2414 /* Aa calibration register 32bit */
+#define MLX90632_EE_Ab               0x2416 /* Ab calibration register 32bit */
+#define MLX90632_EE_Ba               0x2418 /* Ba calibration register 32bit */
+#define MLX90632_EE_Bb               0x241a /* Bb calibration register 32bit */
+#define MLX90632_EE_Ca               0x241c /* Ca calibration register 32bit */
+#define MLX90632_EE_Cb               0x241e /* Cb calibration register 32bit */
+#define MLX90632_EE_Da               0x2420 /* Da calibration register 32bit */
+#define MLX90632_EE_Db               0x2422 /* Db calibration register 32bit */
+#define MLX90632_EE_Ea               0x2424 /* Ea calibration register 32bit */
+#define MLX90632_EE_Eb               0x2426 /* Eb calibration register 32bit */
+#define MLX90632_EE_Fa               0x2428 /* Fa calibration register 32bit */
+#define MLX90632_EE_Fb               0x242a /* Fb calibration register 32bit */
+#define MLX90632_EE_Ga               0x242c /* Ga calibration register 32bit */
+
+#define MLX90632_EE_Gb               0x242e /* Gb calibration register 16bit */
+#define MLX90632_EE_Ka               0x242f /* Ka calibration register 16bit */
+
+#define MLX90632_EE_Ha               0x2481 /* Ha customer calib value reg 16bit */
+#define MLX90632_EE_Hb               0x2482 /* Hb customer calib value reg 16bit */
+
+/* Register addresses - volatile */
+#define MLX90632_REG_I2C_ADDR        0x3000 /* Chip I2C address register */
+
+/* Control register address - volatile */
+#define MLX90632_REG_CONTROL 0x3001 /* Control Register address */
+#define   MLX90632_CFG_PWR_MASK              GENMASK(2, 1) /* PowerMode Mask */
+/* PowerModes statuses */
+#define MLX90632_PWR_STATUS(ctrl_val) (ctrl_val << 1)
+#define MLX90632_PWR_STATUS_HALT MLX90632_PWR_STATUS(0) /* hold */
+#define MLX90632_PWR_STATUS_SLEEP_STEP MLX90632_PWR_STATUS(1) /* sleep step*/
+#define MLX90632_PWR_STATUS_STEP MLX90632_PWR_STATUS(2) /* step */
+#define MLX90632_PWR_STATUS_CONTINUOUS MLX90632_PWR_STATUS(3) /* continuous*/
+
+/* Device status register - volatile */
+#define MLX90632_REG_STATUS  0x3fff /* Device status register */
+#define   MLX90632_STAT_BUSY         BIT(10) /* Device busy indicator */
+#define   MLX90632_STAT_EE_BUSY              BIT(9) /* EEPROM busy indicator */
+#define   MLX90632_STAT_BRST         BIT(8) /* Brown out reset indicator */
+#define   MLX90632_STAT_CYCLE_POS    GENMASK(6, 2) /* Data position */
+#define   MLX90632_STAT_DATA_RDY     BIT(0) /* Data ready indicator */
+
+/* RAM_MEAS address-es for each channel */
+#define MLX90632_RAM_1(meas_num)     (MLX90632_ADDR_RAM + 3 * meas_num)
+#define MLX90632_RAM_2(meas_num)     (MLX90632_ADDR_RAM + 3 * meas_num + 1)
+#define MLX90632_RAM_3(meas_num)     (MLX90632_ADDR_RAM + 3 * meas_num + 2)
+
+/* Magic constants */
+#define MLX90632_EEPROM_VERSION      0xff05 /* EEPROM DSP version for constants */
+#define MLX90632_ID_MEDICAL  0x01ff /* EEPROM Medical device id */
+#define MLX90632_ID_CONSUMER 0x02ff /* EEPROM Consumer device id */
+#define MLX90632_EEPROM_WRITE_KEY 0x554C /* EEPROM write key 0x55 and 0x4c */
+#define MLX90632_RESET_CMD   0x0006 /* Reset sensor (address or global) */
+#define MLX90632_REF_12              12LL /**< ResCtrlRef value of Ch 1 or Ch 2 */
+#define MLX90632_REF_3               12LL /**< ResCtrlRef value of Channel 3 */
+
+#define TENTO3                       1000LL
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 101

Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+#define TENTO4                       10000LL
+#define TENTO5                       100000LL
+#define TENTO6                       1000000LL
+#define TENTO7                       10000000LL
+#define TENTO10                      10000000000LL
+#define TENTO12                      1000000000000LL

Umm. The numbers describe the constants rather better than the defines ;) Just use the numbers if you need them!

Quoted 2 lines

This is way shorter (line length) and more readable in my opinion. Also writing 12 times 0 is error prone :D

Needs care but I really don't like these constants.

Quoted 73 lines
Quoted 63 lines
Quoted 63 lines
drivers/iio/temperature/mlx90632.c new file +62 -0
+
+struct mlx90632_data {
+     struct i2c_client *client;
+     struct mutex lock; /* Multiple reads for single measurement */
+     struct regmap *regmap;
+     u16 emissivity;
+};
+
+static const struct regmap_range mlx90632_volatile_reg_range[] = {
+     regmap_reg_range(MLX90632_REG_CONTROL, MLX90632_REG_I2C_ADDR),
+     regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
+     regmap_reg_range(MLX90632_RAM_1(0),
+                      MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_volatile_regs_tbl = {
+     .yes_ranges = mlx90632_volatile_reg_range,
+     .n_yes_ranges = ARRAY_SIZE(mlx90632_volatile_reg_range),
+};
+
+static const struct regmap_range mlx90632_read_reg_range[] = {
+     regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
+     regmap_reg_range(MLX90632_EE_CTRL, MLX90632_EE_I2C_ADDR),
+     regmap_reg_range(MLX90632_EE_Ha, MLX90632_EE_Hb),
+     regmap_reg_range(MLX90632_REG_CONTROL, MLX90632_REG_I2C_ADDR),
+     regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
+     regmap_reg_range(MLX90632_RAM_1(0),
+                      MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_readable_regs_tbl = {
+     .yes_ranges = mlx90632_read_reg_range,
+     .n_yes_ranges = ARRAY_SIZE(mlx90632_read_reg_range),
+};
+
+static const struct regmap_range mlx90632_no_write_reg_range[] = {
+     regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
+     regmap_reg_range(MLX90632_RAM_1(0),
+                      MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
+};
+
+static const struct regmap_access_table mlx90632_writeable_regs_tbl = {
+     .no_ranges = mlx90632_no_write_reg_range,
+     .n_no_ranges = ARRAY_SIZE(mlx90632_no_write_reg_range),
+};
+
+static const struct regmap_config mlx90632_regmap = {
+     .reg_bits = 16,
+     .val_bits = 16,
+
+     .volatile_table = &mlx90632_volatile_regs_tbl,
+     .rd_table = &mlx90632_readable_regs_tbl,
+     .wr_table = &mlx90632_writeable_regs_tbl,
+
+     .use_single_rw = true,
+     .reg_format_endian = REGMAP_ENDIAN_BIG,
+     .val_format_endian = REGMAP_ENDIAN_BIG,
+     .cache_type = REGCACHE_RBTREE,
+};
+
+static u64 mlx90632_int_sqrt(u64 x)
+{
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 167

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+     u64 b, m, y = 0;
+
+     if (BITS_PER_LONG != 32)
+             return int_sqrt(x);

needs a comment on why...
Ideally propose a standard 64 bit routine if one is needed for 32 bit machines.

Quoted 7 lines

Problem is that int_sqrt is not strongly typed. That means 64 bit number gets truncated to 32bit on 32bit machine as you mentioned and that caused quite many headaches in my testing (worked on mobile phone, but not on beaglebone black). This solution is just stronger typing of int_sqrt function.

If you think I should put it onto math.h as a patch I can try it.

Sure, let's see if that goes anywhere. Seems the right approach to me.

Quoted 104 lines
Quoted 37 lines
Quoted 37 lines
drivers/iio/temperature/mlx90632.c new file +36 -0
+
+     if (x <= 1)
+             return x;
+
+     m = 1ULL << (64 - 2);
+     while (m != 0) {
+             b = y + m;
+             y >>= 1;
+
+             if (x >= b) {
+                     x -= b;
+                     y += m;
+             }
+             m >>= 2;
+     }
+     return y;
+}
+
+static s32 mlx90632_pwr_set_sleep_step(struct regmap *regmap)
+{
+     return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+                               MLX90632_CFG_PWR_MASK,
+                               MLX90632_PWR_STATUS_SLEEP_STEP);
+}
+
+static s32 mlx90632_pwr_set_step(struct regmap *regmap)
+{
+     return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+                               MLX90632_CFG_PWR_MASK,
+                               MLX90632_PWR_STATUS_STEP);
+}
+
+static s32 mlx90632_pwr_continuous(struct regmap *regmap)
+{
+     return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
+                               MLX90632_CFG_PWR_MASK,
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 207

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+                               MLX90632_PWR_STATUS_CONTINUOUS);
+}
+
+static int mlx90632_start_measurement(struct mlx90632_data *data)

Looks superficially to me like this is actually waiting for a reading to complete rather than just starting it? If so change the name to reflect that.

ok

Quoted 20 lines
Quoted 20 lines
drivers/iio/temperature/mlx90632.c new file +20 -0
+{
+     int ret, tries = 100;
+     unsigned int reg_status;
+
+     ret = regmap_update_bits(data->regmap, MLX90632_REG_STATUS,
+                              MLX90632_STAT_DATA_RDY, 0);
+     if (ret < 0)
+             return ret;
+
+     while (tries-- > 0) {
+             ret = regmap_read(data->regmap, MLX90632_REG_STATUS,
+                               &reg_status);
+             if (ret < 0)
+                     return ret;
+             if (reg_status & MLX90632_STAT_DATA_RDY)
+                     break;
+             usleep_range(10000, 11000);
+     }
+
+     if (tries < 0) {
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 232

Quoted 5 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+             dev_err(&data->client->dev, "data not ready");
+             return -ETIMEDOUT;
+     }
+
+     return (reg_status & MLX90632_STAT_CYCLE_POS) >> 2;

This is a non obvious return value so I would suggest adding some documentation to say what is going on here..

Yes, it is indeed.

Quoted 8 lines

drivers/iio/temperature/mlx90632.c line 236

Quoted 4 lines
drivers/iio/temperature/mlx90632.c new file +4 -0
+}
+
+static int mlx9032_channel_new_select(int ret, uint8_t *channel_new,
+                                   uint8_t *channel_old)

don't use ret as a name for a variable being passed in. Rather confusing!

OK. I think I should just copy setting of channel_old and new in the only spot it is used.

Quoted 11 lines
Quoted 11 lines
drivers/iio/temperature/mlx90632.c new file +11 -0
+{
+     if (ret == 1) {
+             *channel_new = 1;
+             *channel_old = 2;
+     } else if (ret == 2) {
+             *channel_new = 2;
+             *channel_old = 1;
+     } else {
+             return ret;
+     }
+     return 0;
Quoted 9 lines
Quoted 6 lines
Quoted 2 lines

Can't get here...

Not true. You get here in every example other than else where channel_new and channel_old are successfully set. but I agree there is a bug in case ret=0 when it will return 0, but it will not set channels.

Ah good point, I missed that. I would do it as a switch with direct returns.

Yes, that is already changed to switch in v2.

Quoted 122 lines
Quoted 122 lines
Quoted 93 lines
Quoted 70 lines
drivers/iio/temperature/mlx90632.c new file +69 -0
+}
+
+static int mlx90632_read_ambient_raw(struct regmap *regmap,
+                                  s16 *ambient_new_raw, s16 *ambient_old_raw)
+{
+     int ret;
+     unsigned int read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_3(1), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *ambient_new_raw = (s16)read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_3(2), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *ambient_old_raw = (s16)read_tmp;
+
+     return ret;
+}
+
+static int mlx90632_read_object_raw(struct regmap *regmap,
+                                 int start_measurement_ret,
+                                 s16 *object_new_raw, s16 *object_old_raw)
+{
+     int ret;
+     unsigned int read_tmp;
+     s16 read;
+     u8 channel = 0;
+     u8 channel_old = 0;
+
+     ret = mlx90632_channel_new_select(start_measurement_ret, &channel,
+                                       &channel_old);
+     if (ret != 0)
+             return ret;
+
+     ret = regmap_read(regmap, MLX90632_RAM_2(channel), &read_tmp);
+     if (ret < 0)
+             return ret;
+
+     read = (s16)read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_1(channel), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *object_new_raw = (read + (s16)read_tmp) / 2;
+
+     ret = regmap_read(regmap, MLX90632_RAM_2(channel_old), &read_tmp);
+     if (ret < 0)
+             return ret;
+     read = (s16)read_tmp;
+
+     ret = regmap_read(regmap, MLX90632_RAM_1(channel_old), &read_tmp);
+     if (ret < 0)
+             return ret;
+     *object_old_raw = (read + (s16)read_tmp) / 2;
+
+     return ret;
+}
+
+static int mlx90632_read_all_channel(struct mlx90632_data *data,
+                                  s16 *ambient_new_raw, s16 *ambient_old_raw,
+                                  s16 *object_new_raw, s16 *object_old_raw)
+{
+     s32 ret, tm_ret;
+
+     mutex_lock(&data->lock);
+     tm_ret = mlx90632_start_measurement(data);
+     if (tm_ret >= 0) {

drivers/iio/temperature/mlx90632.c line 326

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+             ret = mlx90632_read_ambient_raw(data->regmap, ambient_new_raw,
+                                             ambient_old_raw);
+             if (ret >= 0) {
+                     ret = mlx90632_read_object_raw(data->regmap, tm_ret,
+                                                    object_new_raw,
+                                                    object_old_raw);
+             }
+     } else {
+             ret = tm_ret;
+     }

Use something cleaner like

        mutex_lock(&data->lock);
        ret = mlx90632_start_measurement(data);
        if (ret < 0)
                goto unlock;
        ret = mlx90632_read_ambient_raw(data->regmap, ambient_new_raw,
                                        ambient_old_raw);
        if (ret < 0)
                goto unlock;

        ret = mlx90632_read_object_raw(data->regmap, tm_ret,
                                       object_new_raw,
                                       object_old_raw);
Quoted 1 line

unlock:

Ok sorry, professional deformation (goto).

Quoted 24 lines
Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+     mutex_unlock(&data->lock);
+     return ret;
+}
+
+static int mlx90632_read_ee_register(struct regmap *regmap, u16 reg_lsb,
+                                  s32 *reg_value)

drivers/iio/temperature/mlx90632.c line 342

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+{
+     s32 ret;
+     unsigned int read;
+     __le32 value;
+
+     ret = regmap_read(regmap, reg_lsb, &read);
+     if (ret < 0)
+             return ret;
+
+     value = cpu_to_le32(read);

Why would you be converting to le32 to then do
calculations in here using it at cpu endianness?
(guessing you want le32_to_cpu..)

hmm isn't any relevant endian conversion wrapped up in regmap anyway?

Quoted 9 lines
Quoted 4 lines

Regmap reads 16 bit values, but some values are 32 bit. To avoid CPU endianess affecting this, I am putting it to known time and shift values. This way I ensured it is working on any CPU. le32_to_cpu is in return value.

I'm far from convinced this is a good idea. I would ensure all values are in cpu endianness before combining them based on the read order (which is endian independant)

OK, I see the point. Will try it and send v3 (which will be needed anyway).

Quoted 246 lines
Quoted 246 lines
Quoted 97 lines
Quoted 97 lines
drivers/iio/temperature/mlx90632.c new file +97 -0
+
+     ret = regmap_read(regmap, reg_lsb + 1, &read);
+     if (ret < 0)
+             return ret;
+
+     value = (cpu_to_le32(read) << 16) | (value & 0xffff);
+
+     *reg_value = le32_to_cpu(value);
+     return 0;
+}
+
+static s64 mlx90632_preprocess_temp_amb(s16 ambient_new_raw,
+                                     s16 ambient_old_raw, s16 Gb)
+{
+     s64 VR_Ta, kGb, tmp;
+
+     kGb = ((s64)Gb * TENTO3) >> 10ULL;
+     VR_Ta = (s64)ambient_old_raw * TENTO6 +
+             kGb * div64_s64(((s64)ambient_new_raw * TENTO3),
+                     (MLX90632_REF_3));
+     tmp = div64_s64(
+                      div64_s64(((s64)ambient_new_raw * TENTO12),
+                                (MLX90632_REF_3)), VR_Ta);
+     return div64_s64(tmp << 19ULL, TENTO3);
+}
+
+static s64 mlx90632_preprocess_temp_obj(s16 object_new_raw, s16 object_old_raw,
+                                     s16 ambient_new_raw,
+                                     s16 ambient_old_raw, s16 Ka)
+{
+     s64 VR_IR, kKa, tmp;
+
+     kKa = ((s64)Ka * TENTO3) >> 10ULL;
+     VR_IR = (s64)ambient_old_raw * TENTO6 +
+             kKa * div64_s64(((s64)ambient_new_raw * TENTO3),
+                     (MLX90632_REF_3));
+     tmp = div64_s64(
+                     div64_s64(((s64)((object_new_raw + object_old_raw) / 2)
+                                * TENTO12), (MLX90632_REF_12)), VR_IR);
+     return div64_s64(tmp << 19ULL), TENTO3);
+}
+
+static s32 mlx90632_calc_temp_ambient(s16 ambient_new_raw, s16 ambient_old_raw,
+                                   s32 P_T, s32 P_R, s32 P_G, s32 P_O,
+                                   s16 Gb)
+{
+     s64 Asub, Bsub, Ablock, Bblock, Cblock, AMB, sum;
+
+     AMB = mlx90632_preprocess_temp_amb(ambient_new_raw, ambient_old_raw,
+                                        Gb);
+     Asub = ((s64)P_T * TENTO10) >> 44ULL;
+     Bsub = AMB - (((s64)P_R * TENTO3) >> 8ULL);
+     Ablock = Asub * (Bsub * Bsub);
+     Bblock = (div64_s64(Bsub * TENTO7, P_G)) << 20ULL;
+     Cblock = ((s64)P_O * TENTO10) >> 8ULL;
+
+     sum = div64_s64(Ablock, TENTO6) + Bblock + Cblock;
+
+     return div64_s64(sum, TENTO7);
+}
+
+static s32 mlx90632_calc_temp_object_iteration(s32 prev_object_temp, s64 object,
+                                            s64 TAdut, s32 Fa, s32 Fb,
+                                            s32 Ga, s16 Ha, s16 Hb,
+                                            u16 emissivity)
+{
+     s64 calcedKsTO, calcedKsTA, ir_Alpha, TAdut4, Alpha_corr;
+     s64 Ha_customer, Hb_customer;
+
+     Ha_customer = ((s64)Ha * TENTO6) >> 14ULL;
+     Hb_customer = ((s64)Hb * 100) >> 10ULL;
+
+     calcedKsTO = ((s64)((s64)Ga * (prev_object_temp - 25 * TENTO3)
+                          * TENTO3)) >> 36LL;
+     calcedKsTA = ((s64)(Fb * (TAdut - 25 * TENTO6))) >> 36LL;
+     Alpha_corr = div64_s64((((s64)(Fa * TENTO10) >> 46LL) * Ha_customer),
+                            TENTO3);
+     Alpha_corr *= ((s64)(1 * TENTO6 + calcedKsTO + calcedKsTA));
+     Alpha_corr = emissivity * div64_s64(Alpha_corr, TENTO5);
+     Alpha_corr = div64_s64(Alpha_corr, TENTO3);
+     ir_Alpha = div64_s64((s64)object * TENTO7, Alpha_corr);
+     TAdut4 = (div64_s64(TAdut, TENTO4) + 27315) *
+             (div64_s64(TAdut, TENTO4) + 27315) *
+             (div64_s64(TAdut, TENTO4)  + 27315) *
+             (div64_s64(TAdut, TENTO4) + 27315);
+
+     return (mlx90632_int_sqrt(
+                      mlx90632_int_sqrt(ir_Alpha * TENTO12 + TAdut4)
+                     ) - 27315 - Hb_customer) * 10;
+}
+
+static s32 mlx90632_calc_temp_object(s64 object, s64 ambient, s32 Ea, s32 Eb,
+                                  s32 Fa, s32 Fb, s32 Ga, s16 Ha, s16 Hb,
+                                  u16 tmp_emi)
+{
+     s64 kTA, kTA0, TAdut;
+     s64 temp = 25000;
Quoted 8 lines

drivers/iio/temperature/mlx90632.c line 446

Quoted 7 lines
drivers/iio/temperature/mlx90632.c new file +7 -0
+     s8 i;
+
+     kTA = (Ea * TENTO3) >> 16LL;
+     kTA0 = (Eb * TENTO3) >> 8LL;
+     TAdut = div64_s64(((ambient - kTA0) * TENTO6), kTA) + 25 * TENTO6;
+
+     for (i = 0; i < 5; ++i) {

comment on why iterations are needed would be good here.

This is described in datasheet (the whole calculation). Will add explanatory comment.

Quoted 136 lines
Quoted 118 lines
drivers/iio/temperature/mlx90632.c new file +118 -0
+             temp = mlx90632_calc_temp_object_iteration(temp, object, TAdut,
+                                                        Fa, Fb, Ga, Ha, Hb,
+                                                        tmp_emi);
+     }
+     return temp;
+}
+
+static int mlx90632_calc_object_dsp105(struct mlx90632_data *data, int *val)
+{
+     s32 ret;
+     s32 Ea, Eb, Fa, Fb, Ga;
+     unsigned int read_tmp;
+     s16 Ha, Hb, Gb, Ka;
+     s16 ambient_new_raw, ambient_old_raw, object_new_raw, object_old_raw;
+     s64 object, ambient;
+
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ea, &Ea);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Eb, &Eb);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fa, &Fa);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fb, &Fb);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ga, &Ga);
+     if (ret < 0)
+             return ret;
+     ret = regmap_read(data->regmap, MLX90632_EE_Ha, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Ha = (s16)read_tmp;
+     ret = regmap_read(data->regmap, MLX90632_EE_Hb, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Hb = (s16)read_tmp;
+     ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Gb = (s16)read_tmp;
+     ret = regmap_read(data->regmap, MLX90632_EE_Ka, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Ka = (s16)read_tmp;
+
+     ret = mlx90632_read_all_channel(data,
+                                     &ambient_new_raw, &ambient_old_raw,
+                                     &object_new_raw, &object_old_raw);
+     if (ret < 0)
+             return ret;
+
+     ambient = mlx90632_preprocess_temp_amb(ambient_new_raw,
+                                            ambient_old_raw, Gb);
+     object = mlx90632_preprocess_temp_obj(object_new_raw,
+                                           object_old_raw,
+                                           ambient_new_raw,
+                                           ambient_old_raw, Ka);
+
+     *val = mlx90632_calc_temp_object(object, ambient, Ea, Eb, Fa, Fb, Ga,
+                                      Ha, Hb, data->emissivity);
+     return 0;
+}
+
+static int mlx90632_calc_ambient_dsp105(struct mlx90632_data *data, int *val)
+{
+     s32 ret;
+     unsigned int read_tmp;
+     s32 PT, PR, PG, PO;
+     s16 Gb;
+     s16 ambient_new_raw, ambient_old_raw;
+
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_R, &PR);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_G, &PG);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_T, &PT);
+     if (ret < 0)
+             return ret;
+     ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_O, &PO);
+     if (ret < 0)
+             return ret;
+     ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
+     if (ret < 0)
+             return ret;
+     Gb = (s16)read_tmp;
+
+     ret = mlx90632_read_ambient_raw(data->regmap, &ambient_new_raw,
+                                     &ambient_old_raw);
+     *val = mlx90632_calc_temp_ambient(ambient_new_raw, ambient_old_raw,
+                                       PT, PR, PG, PO, Gb);
+     return ret;
+}
+
+static int mlx90632_read_raw(struct iio_dev *indio_dev,
+                          struct iio_chan_spec const *channel, int *val,
+                          int *val2, long mask)
+{
+     struct mlx90632_data *data = iio_priv(indio_dev);
+     int ret;
+
+     switch (mask) {
+     case IIO_CHAN_INFO_PROCESSED:
+             switch (channel->channel2) {
+             case IIO_MOD_TEMP_AMBIENT:
+                     ret = mlx90632_calc_ambient_dsp105(data, val);
+                     if (ret < 0)
+                             return ret;
+                     return IIO_VAL_INT;
+             case IIO_MOD_TEMP_OBJECT:
+                     ret = mlx90632_calc_object_dsp105(data, val);
+                     if (ret < 0)
+                             return ret;
+                     return IIO_VAL_INT;

drivers/iio/temperature/mlx90632.c line 574

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+             default:
+                     return -EINVAL;
+             }
+     case IIO_CHAN_INFO_CALIBEMISSIVITY:
+             if (data->emissivity == 1000) {
+                     *val = 1;
+                     *val2 = 0;
+             } else {
+                     *val = 0;
+                     *val2 = data->emissivity;

Odd given you are reporting as int + nano
this goes from 1.0 to 0.000000999 in one step?
Seems unlikely.. If it is true then a comment
is needed.

The write is int + micro but this would still be wrong without a factor of 1000.

Quoted 8 lines
Quoted 4 lines

In input (write) below I am adding factor of 1000. I do not know if resolution like that is needed, but you never know what they come up with in real life so I rather left some of the breating space.

The above still doesn't make much sense unless your range is disjoint 0-0.000000999, 1.0 which would be surprising and also doesn't correspond to the write.

I see the error - will fix. Will change in int + micro in the process.

Quoted 130 lines
Quoted 117 lines
Quoted 14 lines
Quoted 14 lines
drivers/iio/temperature/mlx90632.c new file +13 -0
+             }
+             return IIO_VAL_INT_PLUS_NANO;
+
+     default:
+             return -EINVAL;
+     }
+}
+
+static int mlx90632_write_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *channel, int val,
+                           int val2, long mask)
+{
+     struct mlx90632_data *data = iio_priv(indio_dev);
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 592

Quoted 5 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+
+     switch (mask) {
+     case IIO_CHAN_INFO_CALIBEMISSIVITY:
+             if (val < 0 || val2 < 0 || val > 1 ||
+                 (val == 1 && val2 != 0))

I'd add a comment describing what this is doing. I think it is checking for 0-1.0 inclusive?

Yes, exactly. In case you set emissivity outside of range it should not change it and return EINVAL.

Quoted 80 lines
Quoted 80 lines
drivers/iio/temperature/mlx90632.c new file +80 -0
+                     return -EINVAL;
+             data->emissivity = val * 1000 + val2 / 1000;
+             return 0;
+     default:
+             return -EINVAL;
+     }
+}
+
+static const struct iio_chan_spec mlx90632_channels[] = {
+     {
+             .type = IIO_TEMP,
+             .modified = 1,
+             .channel2 = IIO_MOD_TEMP_AMBIENT,
+             .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+     },
+     {
+             .type = IIO_TEMP,
+             .modified = 1,
+             .channel2 = IIO_MOD_TEMP_OBJECT,
+             .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+                     BIT(IIO_CHAN_INFO_CALIBEMISSIVITY),
+     },
+};
+
+static const struct iio_info mlx90632_info = {
+     .read_raw = mlx90632_read_raw,
+     .write_raw = mlx90632_write_raw,
+};
+
+#ifdef CONFIG_PM
+static int mlx90632_sleep(struct mlx90632_data *data)
+{
+     dev_dbg(&data->client->dev, "Requesting sleep");
+     return mlx90632_pwr_set_sleep_step(data->regmap);
+}
+
+static int mlx90632_wakeup(struct mlx90632_data *data)
+{
+     dev_dbg(&data->client->dev, "Requesting wake-up");
+     return mlx90632_pwr_continuous(data->regmap);
+}
+#endif
+
+static int mlx90632_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+     struct iio_dev *indio_dev;
+     struct mlx90632_data *mlx90632;
+     struct regmap *regmap;
+     int ret;
+     unsigned int read;
+
+     indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*mlx90632));
+     if (!indio_dev) {
+             dev_err(&client->dev, "Failed to allocate device");
+             return -ENOMEM;
+     }
+
+     regmap = devm_regmap_init_i2c(client, &mlx90632_regmap);
+     if (IS_ERR(regmap)) {
+             ret = PTR_ERR(regmap);
+             dev_err(&client->dev, "Failed to allocate regmap: %d\n", ret);
+             return ret;
+     }
+
+     mlx90632 = iio_priv(indio_dev);
+     i2c_set_clientdata(client, indio_dev);
+     mlx90632->client = client;
+     mlx90632->regmap = regmap;
+
+     mutex_init(&mlx90632->lock);
+     mlx90632_wakeup(mlx90632);
+
+     indio_dev->dev.parent = &client->dev;
+     indio_dev->name = id->name;
+     indio_dev->modes = INDIO_DIRECT_MODE;
+     indio_dev->info = &mlx90632_info;
+     indio_dev->channels = mlx90632_channels;
+     indio_dev->num_channels = ARRAY_SIZE(mlx90632_channels);
+
Quoted 9 lines

drivers/iio/temperature/mlx90632.c line 678

Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +6 -0
+     ret = regmap_read(mlx90632->regmap, MLX90632_EE_VERSION, &read);
+     if (ret < 0) {
+             dev_err(&client->dev, "read of version failed: %d\n", ret);
+             return ret;
+     }
+     if (read == (MLX90632_EEPROM_VERSION & MLX90632_ID_MEDICAL)) {

This is odd. Why the bitwise and of what look to be two different things entirely?

Quoted 12 lines

If you look at how they are set (high vs low bits) you will see they are complimentary and
prepared exactly for bitwise check. ID_MEDICAL might not be best name, but EEPROM_ID_MEDICAL was just too long. You read 16 bits and that is why lower 8 bits
are in fact EEPROM_VERSION while higher 8 are ID of calibration. Since calculations
are currently dependent on lower 8 bits, I left some of the wiggle space for future.
In case we add another one in future, but I would rather have a strict check for this to
avoid any kind of confusion what is supported.

Quoted 9 lines

Surely should be | then?

read == (0xff05 & 0x01ff)

read == (0x105)
So only 3 bits of overlap?

Definitely needs a comment to explain this int the code.

Nothing overlaps - thats the point. Just lower 8 bits are EEPROM_VERSION and the higher are ID.
Will add a comment.

Quoted 27 lines
Quoted 27 lines
Quoted 26 lines
Quoted 6 lines
drivers/iio/temperature/mlx90632.c new file +5 -0
+             dev_dbg(&client->dev,
+                     "Detected Medical EEPROM calibration %x", read);
+     } else if (read == (MLX90632_EEPROM_VERSION & MLX90632_ID_CONSUMER)) {
+             dev_dbg(&client->dev,
+                     "Detected Consumer EEPROM calibration %x", read);

drivers/iio/temperature/mlx90632.c line 693

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+     } else {
+             dev_err(&client->dev,
+                     "Chip EEPROM version mismatch %x (expected %x)",
+                     read, MLX90632_EEPROM_VERSION);
+             return -EPROTONOSUPPORT;
+     }
+
+     mlx90632->emissivity = 1000;
+
+     return devm_iio_device_register(&client->dev, indio_dev);

Don't use devm version. You are (correctly) manually unwinding this in the remove (as you have pm to deal with after removing the interfaces). This will result in a double free I think... return iio_device_register is the way to go.

I'm a bit confused that you don't seem to set up runtime pm anywhere... I would assume we would be looking at autosuspend for a device like this but it isn't enabled..

Quoted 8 lines
Quoted 4 lines

OK, will check how to use iio_device_register instead.

I did not do much of PM on device, so I can't really say. That is why autosuspend is not enabled.

If you are dropping the PM for now, then devm_iio_device_register is fine, just drop the remove function entirely as it won't need to do anything.

In v3 I kept it as it seemed like simple fix, but if it is not really, then I will remove it.

Quoted 140 lines
Quoted 43 lines
Quoted 43 lines
Quoted 28 lines
drivers/iio/temperature/mlx90632.c new file +27 -0
+}
+
+static int mlx90632_remove(struct i2c_client *client)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(client);
+     struct mlx90632_data *data = iio_priv(indio_dev);
+
+     iio_device_unregister(indio_dev);
+
+     pm_runtime_disable(&client->dev);
+     if (!pm_runtime_status_suspended(&client->dev))
+             mlx90632_sleep(data);
+     pm_runtime_set_suspended(&client->dev);
+
+     return 0;
+}
+
+static const struct i2c_device_id mlx90632_id[] = {
+     { "mlx90632", 0 },
+     { }
+};
+MODULE_DEVICE_TABLE(i2c, mlx90632_id);
+
+static const struct of_device_id mlx90632_of_match[] = {
+     { .compatible = "melexis,mlx90632" },
+     { }
+};

drivers/iio/temperature/mlx90632.c line 730

Quoted 10 lines
drivers/iio/temperature/mlx90632.c new file +10 -0
+MODULE_DEVICE_TABLE(of, mlx90632_of_match);
+
+#ifdef CONFIG_PM_SLEEP
+static int mlx90632_pm_suspend(struct device *dev)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *data = iio_priv(indio_dev);
+
+     if (pm_runtime_active(dev))
+             return mlx90632_sleep(data);

I'm a little confused as to why, if the device is powered up fully and a suspend comes in we have to do less than we do in runtime pm case.

Quoted 7 lines
Quoted 2 lines

Am I missing something?

I think I have mostly tested runtime pm case, so this might have been missed. I did get wrong results if I did not mark regcache as dirty.

I will just remove the whole PM thing to start with and add it up later, OK?

Makes sense.

Quoted 78 lines
Quoted 70 lines
Quoted 70 lines
drivers/iio/temperature/mlx90632.c new file +69 -0
+
+     return 0;
+}
+
+static int mlx90632_pm_resume(struct device *dev)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *data = iio_priv(indio_dev);
+     int err;
+
+     err = mlx90632_wakeup(data);
+     if (err < 0)
+             return err;
+
+     pm_runtime_disable(dev);
+     pm_runtime_set_active(dev);
+     pm_runtime_enable(dev);
+
+     return 0;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int mlx90632_pm_runtime_suspend(struct device *dev)
+{
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *mlx90632 = iio_priv(indio_dev);
+
+     regcache_sync(mlx90632->regmap);
+
+     return mlx90632_sleep(mlx90632);
+}
+
+static int mlx90632_pm_runtime_resume(struct device *dev)
+{
+     s32 ret;
+     struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+     struct mlx90632_data *mlx90632 = iio_priv(indio_dev);
+
+     regcache_mark_dirty(mlx90632->regmap);
+     regcache_cache_only(mlx90632->regmap, false);
+     ret = regcache_sync(mlx90632->regmap);
+     if (ret < 0) {
+             dev_err(dev, "Failed to sync regmap registers: %d\n", ret);
+             return ret;
+     }
+
+     return mlx90632_wakeup(mlx90632);
+}
+#endif
+
+static const struct dev_pm_ops mlx90632_pm_ops = {
+     SET_SYSTEM_SLEEP_PM_OPS(mlx90632_pm_suspend, mlx90632_pm_resume)
+     SET_RUNTIME_PM_OPS(mlx90632_pm_runtime_suspend,
+                        mlx90632_pm_runtime_resume, NULL)
+};
+
+static struct i2c_driver mlx90632_driver = {
+     .driver = {
+             .name   = "mlx90632",
+             .of_match_table = mlx90632_of_match,
+             .pm     = &mlx90632_pm_ops,
+     },
+     .probe = mlx90632_probe,
+     .remove = mlx90632_remove,
+     .id_table = mlx90632_id,
+};
+module_i2c_driver(mlx90632_driver);
+
Quoted 8 lines

drivers/iio/temperature/mlx90632.c line 802

Quoted 3 lines
drivers/iio/temperature/mlx90632.c new file +3 -0
+MODULE_AUTHOR("Crt Mori <[email protected]>");
+MODULE_DESCRIPTION("Melexis MLX90632 contactless Infra Red temperature sensor driver");
+MODULE_LICENSE("GPL v2");

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Quoted 4 lines

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