Add Richtek RTQ6056 support

From: ChiYuan Huang <[email protected]>

Add the documentation for Richtek rtq6056.

Signed-off-by ChiYuan Huang <[email protected]>

---
Since v3

From: ChiYuan Huang <[email protected]>

Add Richtek rtq6056 supporting.

It can be used for the system to monitor load current and power with 16-bit resolution.

Signed-off-by ChiYuan Huang <[email protected]>

---
Since v3
- Refine pm_runtime API calling order in 'read_channel' API.
- Fix vshunt wrong scale for divider.
- Refine the comment text.
- Use 'devm_add_action_or_reset' to decrease the code usage in probe function.
- Use RUNTIME_PM_OPS to replace SET_RUNTIME_PM_OPS.
- minor fix for the comma.
- Use pm_ptr to replace the direct assigned pm_ops.

Since v2
- Rename file from 'rtq6056-adc' to 'rtq6056'.
- Refine the ABI, if generic already defined it, remove it and check the channel report unit.
- Add copyright text.
- include the correct header.
- change the property parsing name.
- To use iio_chan_spec address field.
- Refine each channel separate and shared_by_all.
- Use pm_runtime and pm_runtime_autosuspend.
- Remove the shutdown callback. From the HW suggestion, it's not recommended to use battery as the power supply.
- Check all scale unit (voltage->mV, current->mA, power->milliWatt).
- Use the read_avail to provide the interface for attribute value list.
- Add comma for the last element in the const integer array.
- Refine each ADC label text.
- In read_label callback, replace snprintf to sysfs_emit.

---
 .../ABI/testing/sysfs-bus-iio-adc-rtq6056          |   6 +
 drivers/iio/adc/Kconfig                            |  15 +
 drivers/iio/adc/Makefile                           |   1 +
 drivers/iio/adc/rtq6056.c                          | 651 +++++++++++++++++++++
 4 files changed, 673 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-adc-rtq6056
 create mode 100644 drivers/iio/adc/rtq6056.c

Documentation/ABI/testing/sysfs-bus-iio-adc-rtq6056 new file +6 -0

new file mode 100644
index 00000000..db54343
@@ -0,0 +1,6 @@
+What:          /sys/bus/iio/devices/iio:deviceX/in_voltage0_integration_time
+What:          /sys/bus/iio/devices/iio:deviceX/in_voltage1_integration_time
+KernelVersion: 5.15.31
+Contact:       [email protected]
+Description:
+               Each voltage conversion time in uS

drivers/iio/adc/Kconfig +15 -0

index 48ace74..caebd1a 100644
@@ -908,6 +908,21 @@ config ROCKCHIP_SARADC
          To compile this driver as a module, choose M here: the
          module will be called rockchip_saradc.
 
+config RICHTEK_RTQ6056
+       tristate "Richtek RTQ6056 Current and Power Monitor ADC"
+       depends on I2C
+       select REGMAP_I2C
+       select IIO_BUFFER
+       select IIO_TRIGGERED_BUFFER
+       help
+         Say yes here to enable RQT6056 ADC support.
+         RTQ6056 is a high accuracy current-sense monitor with I2C and SMBus
+         compatible interface, and the device provides full information for
+         system by reading out the load current and power.
+
+         This driver can also be built as a module. If so, the module will be
+         called rtq6056.
+
 config RZG2L_ADC
        tristate "Renesas RZ/G2L ADC driver"
        depends on ARCH_RZG2L || COMPILE_TEST

drivers/iio/adc/Makefile +1 -0

index 39d806f..cda7580 100644
@@ -84,6 +84,7 @@ obj-$(CONFIG_QCOM_PM8XXX_XOADC) += qcom-pm8xxx-xoadc.o
 obj-$(CONFIG_RCAR_GYRO_ADC) += rcar-gyroadc.o
 obj-$(CONFIG_RN5T618_ADC) += rn5t618-adc.o
 obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o
+obj-$(CONFIG_RICHTEK_RTQ6056) += rtq6056.o
 obj-$(CONFIG_RZG2L_ADC) += rzg2l_adc.o
 obj-$(CONFIG_SC27XX_ADC) += sc27xx_adc.o
 obj-$(CONFIG_SPEAR_ADC) += spear_adc.o

drivers/iio/adc/rtq6056.c new file +651 -1

new file mode 100644
index 00000000..c97c8af
@@ -0,0 +1,651 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Richtek Technology Corp.
+ *
+ * ChiYuan Huang <[email protected]>
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/util_macros.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define RTQ6056_REG_CONFIG     0x00
+#define RTQ6056_REG_SHUNTVOLT  0x01
+#define RTQ6056_REG_BUSVOLT    0x02
+#define RTQ6056_REG_POWER      0x03
+#define RTQ6056_REG_CURRENT    0x04
+#define RTQ6056_REG_CALIBRATION        0x05
+#define RTQ6056_REG_MASKENABLE 0x06
+#define RTQ6056_REG_ALERTLIMIT 0x07
+#define RTQ6056_REG_MANUFACTID 0xFE
+#define RTQ6056_REG_DIEID      0xFF
+
+#define RTQ6056_VENDOR_ID      0x1214
+#define RTQ6056_DEFAULT_CONFIG 0x4127
+#define RTQ6056_CONT_ALLON     7
+
+enum {
+       RTQ6056_CH_VSHUNT = 0,
+       RTQ6056_CH_VBUS,
+       RTQ6056_CH_POWER,
+       RTQ6056_CH_CURRENT,
+       RTQ6056_MAX_CHANNEL
+};
+
+enum {
+       F_OPMODE = 0,
+       F_VSHUNTCT,
+       F_VBUSCT,
+       F_AVG,
+       F_RESET,
+       F_MAX_FIELDS
+};
+
+struct rtq6056_priv {
+       struct device *dev;
+       struct regmap *regmap;
+       struct regmap_field *rm_fields[F_MAX_FIELDS];
+       u32 shunt_resistor_uohm;
+       int vshuntct_us;
+       int vbusct_us;
+       int avg_sample;
+};
+
+static const struct reg_field rtq6056_reg_fields[F_MAX_FIELDS] = {
+       [F_OPMODE] = REG_FIELD(RTQ6056_REG_CONFIG, 0, 2),
+       [F_VSHUNTCT] = REG_FIELD(RTQ6056_REG_CONFIG, 3, 5),
+       [F_VBUSCT] = REG_FIELD(RTQ6056_REG_CONFIG, 6, 8),
+       [F_AVG] = REG_FIELD(RTQ6056_REG_CONFIG, 9, 11),
+       [F_RESET] = REG_FIELD(RTQ6056_REG_CONFIG, 15, 15),
+};
+
+static const struct iio_chan_spec rtq6056_channels[RTQ6056_MAX_CHANNEL + 1] = {
+       {
+               .type = IIO_VOLTAGE,
+               .indexed = 1,
+               .channel = 0,
+               .address = RTQ6056_REG_SHUNTVOLT,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+                                     BIT(IIO_CHAN_INFO_SCALE) |
+                                     BIT(IIO_CHAN_INFO_INT_TIME),
+               .info_mask_separate_available = BIT(IIO_CHAN_INFO_INT_TIME),
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+                                          BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .scan_index = 0,
+               .scan_type = {
+                       .sign = 's',
+                       .realbits = 16,
+                       .storagebits = 16,
+                       .endianness = IIO_CPU,
+               },
+       },
+       {
+               .type = IIO_VOLTAGE,
+               .indexed = 1,
+               .channel = 1,
+               .address = RTQ6056_REG_BUSVOLT,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+                                     BIT(IIO_CHAN_INFO_SCALE) |
+                                     BIT(IIO_CHAN_INFO_INT_TIME),
+               .info_mask_separate_available = BIT(IIO_CHAN_INFO_INT_TIME),
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+                                          BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .scan_index = 1,
+               .scan_type = {
+                       .sign = 'u',
+                       .realbits = 16,
+                       .storagebits = 16,
+                       .endianness = IIO_CPU,
+               },
+       },
+       {
+               .type = IIO_POWER,
+               .indexed = 1,
+               .channel = 2,
+               .address = RTQ6056_REG_POWER,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+                                     BIT(IIO_CHAN_INFO_SCALE),
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+                                          BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .scan_index = 2,
+               .scan_type = {
+                       .sign = 'u',
+                       .realbits = 16,
+                       .storagebits = 16,
+                       .endianness = IIO_CPU,
+               },
+       },
+       {
+               .type = IIO_CURRENT,
+               .indexed = 1,
+               .channel = 3,
+               .address = RTQ6056_REG_CURRENT,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+                                          BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .scan_index = 3,
+               .scan_type = {
+                       .sign = 's',
+                       .realbits = 16,
+                       .storagebits = 16,
+                       .endianness = IIO_CPU,
+               },
+       },
+       IIO_CHAN_SOFT_TIMESTAMP(RTQ6056_MAX_CHANNEL),
+};
+
+static int rtq6056_adc_read_channel(struct rtq6056_priv *priv,
+                                   struct iio_chan_spec const *ch,
+                                   int *val)
+{
+       struct device *dev = priv->dev;
+       unsigned int addr = ch->address;
+       unsigned int regval;
+       int ret;
+
+       pm_runtime_get_sync(dev);
+       ret = regmap_read(priv->regmap, addr, &regval);
+       pm_runtime_mark_last_busy(dev);
+       pm_runtime_put(dev);
+       if (ret)
+               return ret;
+
+       /* Power and VBUS is unsigned 16-bit, others are signed 16-bit */
+       if (addr == RTQ6056_REG_BUSVOLT || addr == RTQ6056_REG_POWER)
+               *val = regval;
+       else
+               *val = sign_extend32(regval, 16);
+
+
+       return IIO_VAL_INT;
+}
+
+static int rtq6056_adc_read_scale(struct iio_chan_spec const *ch, int *val,
+                                 int *val2)
+{
+       switch (ch->address) {
+       case RTQ6056_REG_SHUNTVOLT:
+               /* VSHUNT lsb  2.5uV */
+               *val = 2500;
+               *val2 = 1000000;
+               return IIO_VAL_FRACTIONAL;
+       case RTQ6056_REG_BUSVOLT:
+               /* VBUS lsb 1.25mV */
+               *val = 1250;
+               *val2 = 1000;
+               return IIO_VAL_FRACTIONAL;
+       case RTQ6056_REG_POWER:
+               /* Power lsb 25mW */
+               *val = 25;
+               return IIO_VAL_INT;
+       default:
+               return -EINVAL;
+       }
+}
+
+/*
+ * Conversion time in uS for channel VSHUNT and VBUS. The indices correspond
+ * with the bit value expected by the chip. And it can be found at
+ * https://www.richtek.com/assets/product_file/RTQ6056/DSQ6056-00.pdf
+ */
+static const int rtq6056_conv_time_list[] = {
+       139, 203, 269, 525, 1037, 2061, 4109, 8205,
+};
+
+static int rtq6056_adc_set_conv_time(struct rtq6056_priv *priv,
+                                    struct iio_chan_spec const *ch,
+                                    int val)
+{
+       struct regmap_field *rm_field;
+       unsigned int selector;
+       int *ct, ret;
+
+       if (val > 8205 || val < 139)
+               return -EINVAL;
+
+       if (ch->address == RTQ6056_REG_SHUNTVOLT) {
+               rm_field = priv->rm_fields[F_VSHUNTCT];
+               ct = &priv->vshuntct_us;
+       } else {
+               rm_field = priv->rm_fields[F_VBUSCT];
+               ct = &priv->vbusct_us;
+       }
+
+       selector = find_closest(val, rtq6056_conv_time_list,
+                               ARRAY_SIZE(rtq6056_conv_time_list));
+
+       ret = regmap_field_write(rm_field, selector);
+       if (ret)
+               return ret;
+
+       *ct = rtq6056_conv_time_list[selector];
+
+       return 0;
+}
+
+/*
+ * Available averaging rate for rtq6056. The indices correspond with the bit
+ * value expected by the chip. And it can be found at
+ * https://www.richtek.com/assets/product_file/RTQ6056/DSQ6056-00.pdf
+ */
+static const int rtq6056_avg_sample_list[] = {
+       1, 4, 16, 64, 128, 256, 512, 1024,
+};
+
+static int rtq6056_adc_set_average(struct rtq6056_priv *priv, int val)
+{
+       unsigned int selector;
+       int ret;
+
+       if (val > 1024 || val < 1)
+               return -EINVAL;
+
+       selector = find_closest(val, rtq6056_avg_sample_list,
+                               ARRAY_SIZE(rtq6056_avg_sample_list));
+
+       ret = regmap_field_write(priv->rm_fields[F_AVG], selector);
+       if (ret)
+               return ret;
+
+       priv->avg_sample = rtq6056_avg_sample_list[selector];
+
+       return 0;
+}
+
+static int rtq6056_adc_get_sample_freq(struct rtq6056_priv *priv, int *val)
+{
+       int sample_time;
+
+       sample_time = priv->vshuntct_us + priv->vbusct_us;
+       sample_time *= priv->avg_sample;
+
+       *val = DIV_ROUND_UP(1000000, sample_time);
+
+       return IIO_VAL_INT;
+}
+
+static int rtq6056_adc_read_raw(struct iio_dev *indio_dev,
+                               struct iio_chan_spec const *chan, int *val,
+                               int *val2, long mask)
+{
+       struct rtq6056_priv *priv = iio_priv(indio_dev);
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+               return rtq6056_adc_read_channel(priv, chan, val);
+       case IIO_CHAN_INFO_SCALE:
+               return rtq6056_adc_read_scale(chan, val, val2);
+       case IIO_CHAN_INFO_INT_TIME:
+               if (chan->address == RTQ6056_REG_SHUNTVOLT)
+                       *val = priv->vshuntct_us;
+               else
+                       *val = priv->vbusct_us;
+
+               return IIO_VAL_INT;
+       case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+               *val = priv->avg_sample;
+               return IIO_VAL_INT;
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               return rtq6056_adc_get_sample_freq(priv, val);
+       default:
+               return -EINVAL;
+       }
+}
+
+static int rtq6056_adc_read_avail(struct iio_dev *indio_dev,
+                                 struct iio_chan_spec const *chan,
+                                 const int **vals, int *type, int *length,
+                                 long mask)
+{
+       switch (mask) {
+       case IIO_CHAN_INFO_INT_TIME:
+               *vals = rtq6056_conv_time_list;
+               *type = IIO_VAL_INT;
+               *length = ARRAY_SIZE(rtq6056_conv_time_list);
+               return IIO_AVAIL_LIST;
+       case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+               *vals = rtq6056_avg_sample_list;
+               *type = IIO_VAL_INT;
+               *length = ARRAY_SIZE(rtq6056_avg_sample_list);
+               return IIO_AVAIL_LIST;
+       default:
+               return -EINVAL;
+       }
+}
+
+static int rtq6056_adc_write_raw(struct iio_dev *indio_dev,
+                                struct iio_chan_spec const *chan, int val,
+                                int val2, long mask)
+{
+       struct rtq6056_priv *priv = iio_priv(indio_dev);
+
+       if (iio_buffer_enabled(indio_dev))
+               return -EBUSY;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_INT_TIME:
+               return rtq6056_adc_set_conv_time(priv, chan, val);
+       case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+               return rtq6056_adc_set_average(priv, val);
+       default:
+               return -EINVAL;
+       }
+}
+
+static const char *rtq6056_channel_labels[RTQ6056_MAX_CHANNEL] = {
+       [RTQ6056_CH_VSHUNT] = "Vshunt",
+       [RTQ6056_CH_VBUS] = "Vbus",
+       [RTQ6056_CH_POWER] = "Power",
+       [RTQ6056_CH_CURRENT] = "Current",
+};
+
+static int rtq6056_adc_read_label(struct iio_dev *indio_dev,
+                                 struct iio_chan_spec const *chan,
+                                 char *label)
+{
+       return sysfs_emit(label, "%s\n", rtq6056_channel_labels[chan->channel]);
+}
+
+static int rtq6056_set_shunt_resistor(struct rtq6056_priv *priv,
+                                     int resistor_uohm)
+{
+       unsigned int calib_val;
+       int ret;
+
+       if (resistor_uohm <= 0) {
+               dev_err(priv->dev, "Invalid resistor [%d]\n", resistor_uohm);
+               return -EINVAL;
+       }
+
+       /* calibration = 5120000 / (Rshunt (uOhm) * current lsb (1mA)) */
+       calib_val = 5120000 / resistor_uohm;
+       ret = regmap_write(priv->regmap, RTQ6056_REG_CALIBRATION, calib_val);
+       if (ret)
+               return ret;
+
+       priv->shunt_resistor_uohm = resistor_uohm;
+
+       return 0;
+}
+
+static ssize_t shunt_resistor_show(struct device *dev,
+                                  struct device_attribute *attr, char *buf)
+{
+       struct rtq6056_priv *priv = iio_priv(dev_to_iio_dev(dev));
+       int vals[2] = { priv->shunt_resistor_uohm, 1000000 };
+
+       return iio_format_value(buf, IIO_VAL_FRACTIONAL, 1, vals);
+}
+
+static ssize_t shunt_resistor_store(struct device *dev,
+                                   struct device_attribute *attr,
+                                   const char *buf, size_t len)
+{
+       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+       struct rtq6056_priv *priv = iio_priv(indio_dev);
+       int val, val_fract, ret;
+
+       if (iio_buffer_enabled(indio_dev))
+               return -EBUSY;
+
+       ret = iio_str_to_fixpoint(buf, 100000, &val, &val_fract);
+       if (ret)
+               return ret;
+
+       ret = rtq6056_set_shunt_resistor(priv, val * 1000000 + val_fract);
+       if (ret)
+               return ret;
+
+       return len;
+}
+
+static IIO_DEVICE_ATTR_RW(shunt_resistor, 0);
+
+static struct attribute *rtq6056_attributes[] = {
+       &iio_dev_attr_shunt_resistor.dev_attr.attr,
+       NULL
+};
+
+static const struct attribute_group rtq6056_attribute_group = {
+       .attrs = rtq6056_attributes,
+};
+
+static const struct iio_info rtq6056_info = {
+       .attrs = &rtq6056_attribute_group,
+       .read_raw = rtq6056_adc_read_raw,
+       .read_avail = rtq6056_adc_read_avail,
+       .write_raw = rtq6056_adc_write_raw,
+       .read_label = rtq6056_adc_read_label,
+};
+
+static irqreturn_t rtq6056_buffer_trigger_handler(int irq, void *p)
+{
+       struct iio_poll_func *pf = p;
+       struct iio_dev *indio_dev = pf->indio_dev;
+       struct rtq6056_priv *priv = iio_priv(indio_dev);
+       struct device *dev = priv->dev;
+       struct {
+               u16 vals[RTQ6056_MAX_CHANNEL];
+               int64_t timestamp;
+       } data;
+       unsigned int raw;
+       int i = 0, bit, ret;
+
+       memset(&data, 0, sizeof(data));
+
+       pm_runtime_get_sync(dev);
+
+       for_each_set_bit(bit, indio_dev->active_scan_mask, indio_dev->masklength) {
+               unsigned int addr = rtq6056_channels[bit].address;
+
+               ret = regmap_read(priv->regmap, addr, &raw);
+               if (ret)
+                       goto out;
+
+               data.vals[i++] = raw;
+       }
+
+       iio_push_to_buffers_with_timestamp(indio_dev, &data, iio_get_time_ns(indio_dev));
+
+out:
+       pm_runtime_mark_last_busy(dev);
+       pm_runtime_put(dev);
+
+       iio_trigger_notify_done(indio_dev->trig);
+
+       return IRQ_HANDLED;
+}
+
+static void rtq6056_remove(void *dev)
+{
+       pm_runtime_dont_use_autosuspend(dev);
+       pm_runtime_disable(dev);
+       pm_runtime_set_suspended(dev);
+}
+
+static bool rtq6056_is_readable_reg(struct device *dev, unsigned int reg)
+{
+       switch (reg) {
+       case RTQ6056_REG_CONFIG ... RTQ6056_REG_ALERTLIMIT:
+       case RTQ6056_REG_MANUFACTID ... RTQ6056_REG_DIEID:
+               return true;
+       default:
+               return false;
+       }
+}
+
+static bool rtq6056_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+       switch (reg) {
+       case RTQ6056_REG_CONFIG:
+       case RTQ6056_REG_CALIBRATION ... RTQ6056_REG_ALERTLIMIT:
+               return true;
+       default:
+               return false;
+       }
+}
+
+static const struct regmap_config rtq6056_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 16,
+       .val_format_endian = REGMAP_ENDIAN_BIG,
+       .max_register = RTQ6056_REG_DIEID,
+       .readable_reg = rtq6056_is_readable_reg,
+       .writeable_reg = rtq6056_is_writeable_reg,
+};
+
+static int rtq6056_probe(struct i2c_client *i2c)
+{
+       struct iio_dev *indio_dev;
+       struct rtq6056_priv *priv;
+       struct device *dev = &i2c->dev;
+       struct regmap *regmap;
+       unsigned int vendor_id, shunt_resistor_uohm;
+       int ret;
+
+       if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_WORD_DATA))
+               return -EOPNOTSUPP;
+
+       indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
+       if (!indio_dev)
+               return -ENOMEM;
+
+       priv = iio_priv(indio_dev);
+       priv->dev = dev;
+       priv->vshuntct_us = priv->vbusct_us = 1037;
+       priv->avg_sample = 1;
+       i2c_set_clientdata(i2c, priv);
+
+       regmap = devm_regmap_init_i2c(i2c, &rtq6056_regmap_config);
+       if (IS_ERR(regmap))
+               return dev_err_probe(dev, PTR_ERR(regmap),
+                                    "Failed to init regmap\n");
+
+       priv->regmap = regmap;
+
+       ret = regmap_read(regmap, RTQ6056_REG_MANUFACTID, &vendor_id);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Failed to get manufacturer info\n");
+
+       if (vendor_id != RTQ6056_VENDOR_ID)
+               return dev_err_probe(dev, -ENODEV,
+                                    "Invalid vendor id 0x%04x\n", vendor_id);
+
+       ret = devm_regmap_field_bulk_alloc(dev, regmap, priv->rm_fields,
+                                          rtq6056_reg_fields, F_MAX_FIELDS);
+       if (ret)
+               return dev_err_probe(dev, ret, "Failed to init regmap field\n");
+
+       /*
+        * By default, configure average sample as 1, bus and shunt conversion
+        * timea as 1037 microsecond, and operating mode to all on.
+        */
+       ret = regmap_write(regmap, RTQ6056_REG_CONFIG, RTQ6056_DEFAULT_CONFIG);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Failed to enable continuous sensing\n");
+
+       pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC);
+       pm_runtime_use_autosuspend(dev);
+       pm_runtime_set_active(dev);
+       pm_runtime_mark_last_busy(dev);
+       pm_runtime_enable(dev);
+
+       ret = devm_add_action_or_reset(dev, rtq6056_remove, dev);
+       if (ret)
+               return ret;
+
+       /* By default, use 2000 micro-ohm resistor */
+       shunt_resistor_uohm = 2000;
+       device_property_read_u32(dev, "shunt-resistor-micro-ohms",
+                                &shunt_resistor_uohm);
+
+       ret = rtq6056_set_shunt_resistor(priv, shunt_resistor_uohm);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Failed to init shunt resistor\n");
+
+       indio_dev->name = "rtq6056";
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->channels = rtq6056_channels;
+       indio_dev->num_channels = ARRAY_SIZE(rtq6056_channels);
+       indio_dev->info = &rtq6056_info;
+
+       ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
+                                             rtq6056_buffer_trigger_handler,
+                                             NULL);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Failed to allocate iio trigger buffer\n");
+
+       return devm_iio_device_register(dev, indio_dev);
+}
+
+static int rtq6056_runtime_suspend(struct device *dev)
+{
+       struct rtq6056_priv *priv = dev_get_drvdata(dev);
+
+       /* Configure to shutdown mode */
+       return regmap_field_write(priv->rm_fields[F_OPMODE], 0);
+}
+
+static int rtq6056_runtime_resume(struct device *dev)
+{
+       struct rtq6056_priv *priv = dev_get_drvdata(dev);
+       int sample_rdy_time_us, ret;
+
+       ret = regmap_field_write(priv->rm_fields[F_OPMODE], RTQ6056_CONT_ALLON);
+       if (ret)
+               return ret;
+
+       sample_rdy_time_us = priv->vbusct_us + priv->vshuntct_us;
+       sample_rdy_time_us *= priv->avg_sample;
+
+       usleep_range(sample_rdy_time_us, sample_rdy_time_us + 100);
+
+       return 0;
+}
+
+static const struct dev_pm_ops rtq6056_pm_ops = {
+       RUNTIME_PM_OPS(rtq6056_runtime_suspend, rtq6056_runtime_resume, NULL)
+};
+
+static const struct of_device_id rtq6056_device_match[] = {
+       { .compatible = "richtek,rtq6056" },
+       {}
+};
+MODULE_DEVICE_TABLE(of, rtq6056_device_match);
+
+static struct i2c_driver rtq6056_driver = {
+       .driver = {
+               .name = "rtq6056",
+               .of_match_table = rtq6056_device_match,
+               .pm = pm_ptr(&rtq6056_pm_ops),
+       },
+       .probe_new = rtq6056_probe,
+};
+module_i2c_driver(rtq6056_driver);
+
+MODULE_AUTHOR("ChiYuan Huang <[email protected]>");
+MODULE_DESCRIPTION("Richtek RTQ6056 Driver");
+MODULE_LICENSE("GPL v2");
--

2.7.4

Quoted 7 lines

From: ChiYuan Huang <[email protected]>

Add Richtek rtq6056 supporting.

It can be used for the system to monitor load current and power with 16-bit resolution.

With a fixed kernel version (it may not be a stable version, we are now at v5.19 cycle, and it can't be either this cycle),

Reviewed-by Andy Shevchenko <[email protected]>

Quoted 747 lines

Signed-off-by ChiYuan Huang <[email protected]>

---
Since v3
- Refine pm_runtime API calling order in 'read_channel' API.
- Fix vshunt wrong scale for divider.
- Refine the comment text.
- Use 'devm_add_action_or_reset' to decrease the code usage in probe function.
- Use RUNTIME_PM_OPS to replace SET_RUNTIME_PM_OPS.
- minor fix for the comma.
- Use pm_ptr to replace the direct assigned pm_ops.

Since v2
- Rename file from 'rtq6056-adc' to 'rtq6056'.
- Refine the ABI, if generic already defined it, remove it and check the channel report unit.
- Add copyright text.
- include the correct header.
- change the property parsing name.
- To use iio_chan_spec address field.
- Refine each channel separate and shared_by_all.
- Use pm_runtime and pm_runtime_autosuspend.
- Remove the shutdown callback. From the HW suggestion, it's not recommended to use battery as the power supply.
- Check all scale unit (voltage->mV, current->mA, power->milliWatt).
- Use the read_avail to provide the interface for attribute value list.
- Add comma for the last element in the const integer array.
- Refine each ADC label text.
- In read_label callback, replace snprintf to sysfs_emit.

---
 .../ABI/testing/sysfs-bus-iio-adc-rtq6056          |   6 +
 drivers/iio/adc/Kconfig                            |  15 +
 drivers/iio/adc/Makefile                           |   1 +
 drivers/iio/adc/rtq6056.c                          | 651 +++++++++++++++++++++
 4 files changed, 673 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-adc-rtq6056
 create mode 100644 drivers/iio/adc/rtq6056.c

Documentation/ABI/testing/sysfs-bus-iio-adc-rtq6056 new file +6 -0

new file mode 100644
index 00000000..db54343
@@ -0,0 +1,6 @@
+What:          /sys/bus/iio/devices/iio:deviceX/in_voltage0_integration_time
+What:          /sys/bus/iio/devices/iio:deviceX/in_voltage1_integration_time
+KernelVersion: 5.15.31
+Contact:       [email protected]
+Description:
+               Each voltage conversion time in uS

drivers/iio/adc/Kconfig +15 -0

index 48ace74..caebd1a 100644
@@ -908,6 +908,21 @@ config ROCKCHIP_SARADC
          To compile this driver as a module, choose M here: the
          module will be called rockchip_saradc.
 
+config RICHTEK_RTQ6056
+       tristate "Richtek RTQ6056 Current and Power Monitor ADC"
+       depends on I2C
+       select REGMAP_I2C
+       select IIO_BUFFER
+       select IIO_TRIGGERED_BUFFER
+       help
+         Say yes here to enable RQT6056 ADC support.
+         RTQ6056 is a high accuracy current-sense monitor with I2C and SMBus
+         compatible interface, and the device provides full information for
+         system by reading out the load current and power.
+
+         This driver can also be built as a module. If so, the module will be
+         called rtq6056.
+
 config RZG2L_ADC
        tristate "Renesas RZ/G2L ADC driver"
        depends on ARCH_RZG2L || COMPILE_TEST

drivers/iio/adc/Makefile +1 -0

index 39d806f..cda7580 100644
@@ -84,6 +84,7 @@ obj-$(CONFIG_QCOM_PM8XXX_XOADC) += qcom-pm8xxx-xoadc.o
 obj-$(CONFIG_RCAR_GYRO_ADC) += rcar-gyroadc.o
 obj-$(CONFIG_RN5T618_ADC) += rn5t618-adc.o
 obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o
+obj-$(CONFIG_RICHTEK_RTQ6056) += rtq6056.o
 obj-$(CONFIG_RZG2L_ADC) += rzg2l_adc.o
 obj-$(CONFIG_SC27XX_ADC) += sc27xx_adc.o
 obj-$(CONFIG_SPEAR_ADC) += spear_adc.o

drivers/iio/adc/rtq6056.c new file +651 -1

new file mode 100644
index 00000000..c97c8af
@@ -0,0 +1,651 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Richtek Technology Corp.
+ *
+ * ChiYuan Huang <[email protected]>
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/util_macros.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define RTQ6056_REG_CONFIG     0x00
+#define RTQ6056_REG_SHUNTVOLT  0x01
+#define RTQ6056_REG_BUSVOLT    0x02
+#define RTQ6056_REG_POWER      0x03
+#define RTQ6056_REG_CURRENT    0x04
+#define RTQ6056_REG_CALIBRATION        0x05
+#define RTQ6056_REG_MASKENABLE 0x06
+#define RTQ6056_REG_ALERTLIMIT 0x07
+#define RTQ6056_REG_MANUFACTID 0xFE
+#define RTQ6056_REG_DIEID      0xFF
+
+#define RTQ6056_VENDOR_ID      0x1214
+#define RTQ6056_DEFAULT_CONFIG 0x4127
+#define RTQ6056_CONT_ALLON     7
+
+enum {
+       RTQ6056_CH_VSHUNT = 0,
+       RTQ6056_CH_VBUS,
+       RTQ6056_CH_POWER,
+       RTQ6056_CH_CURRENT,
+       RTQ6056_MAX_CHANNEL
+};
+
+enum {
+       F_OPMODE = 0,
+       F_VSHUNTCT,
+       F_VBUSCT,
+       F_AVG,
+       F_RESET,
+       F_MAX_FIELDS
+};
+
+struct rtq6056_priv {
+       struct device *dev;
+       struct regmap *regmap;
+       struct regmap_field *rm_fields[F_MAX_FIELDS];
+       u32 shunt_resistor_uohm;
+       int vshuntct_us;
+       int vbusct_us;
+       int avg_sample;
+};
+
+static const struct reg_field rtq6056_reg_fields[F_MAX_FIELDS] = {
+       [F_OPMODE] = REG_FIELD(RTQ6056_REG_CONFIG, 0, 2),
+       [F_VSHUNTCT] = REG_FIELD(RTQ6056_REG_CONFIG, 3, 5),
+       [F_VBUSCT] = REG_FIELD(RTQ6056_REG_CONFIG, 6, 8),
+       [F_AVG] = REG_FIELD(RTQ6056_REG_CONFIG, 9, 11),
+       [F_RESET] = REG_FIELD(RTQ6056_REG_CONFIG, 15, 15),
+};
+
+static const struct iio_chan_spec rtq6056_channels[RTQ6056_MAX_CHANNEL + 1] = {
+       {
+               .type = IIO_VOLTAGE,
+               .indexed = 1,
+               .channel = 0,
+               .address = RTQ6056_REG_SHUNTVOLT,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+                                     BIT(IIO_CHAN_INFO_SCALE) |
+                                     BIT(IIO_CHAN_INFO_INT_TIME),
+               .info_mask_separate_available = BIT(IIO_CHAN_INFO_INT_TIME),
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+                                          BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .scan_index = 0,
+               .scan_type = {
+                       .sign = 's',
+                       .realbits = 16,
+                       .storagebits = 16,
+                       .endianness = IIO_CPU,
+               },
+       },
+       {
+               .type = IIO_VOLTAGE,
+               .indexed = 1,
+               .channel = 1,
+               .address = RTQ6056_REG_BUSVOLT,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+                                     BIT(IIO_CHAN_INFO_SCALE) |
+                                     BIT(IIO_CHAN_INFO_INT_TIME),
+               .info_mask_separate_available = BIT(IIO_CHAN_INFO_INT_TIME),
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+                                          BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .scan_index = 1,
+               .scan_type = {
+                       .sign = 'u',
+                       .realbits = 16,
+                       .storagebits = 16,
+                       .endianness = IIO_CPU,
+               },
+       },
+       {
+               .type = IIO_POWER,
+               .indexed = 1,
+               .channel = 2,
+               .address = RTQ6056_REG_POWER,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+                                     BIT(IIO_CHAN_INFO_SCALE),
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+                                          BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .scan_index = 2,
+               .scan_type = {
+                       .sign = 'u',
+                       .realbits = 16,
+                       .storagebits = 16,
+                       .endianness = IIO_CPU,
+               },
+       },
+       {
+               .type = IIO_CURRENT,
+               .indexed = 1,
+               .channel = 3,
+               .address = RTQ6056_REG_CURRENT,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+                                          BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+               .scan_index = 3,
+               .scan_type = {
+                       .sign = 's',
+                       .realbits = 16,
+                       .storagebits = 16,
+                       .endianness = IIO_CPU,
+               },
+       },
+       IIO_CHAN_SOFT_TIMESTAMP(RTQ6056_MAX_CHANNEL),
+};
+
+static int rtq6056_adc_read_channel(struct rtq6056_priv *priv,
+                                   struct iio_chan_spec const *ch,
+                                   int *val)
+{
+       struct device *dev = priv->dev;
+       unsigned int addr = ch->address;
+       unsigned int regval;
+       int ret;
+
+       pm_runtime_get_sync(dev);
+       ret = regmap_read(priv->regmap, addr, &regval);
+       pm_runtime_mark_last_busy(dev);
+       pm_runtime_put(dev);
+       if (ret)
+               return ret;
+
+       /* Power and VBUS is unsigned 16-bit, others are signed 16-bit */
+       if (addr == RTQ6056_REG_BUSVOLT || addr == RTQ6056_REG_POWER)
+               *val = regval;
+       else
+               *val = sign_extend32(regval, 16);
+
+
+       return IIO_VAL_INT;
+}
+
+static int rtq6056_adc_read_scale(struct iio_chan_spec const *ch, int *val,
+                                 int *val2)
+{
+       switch (ch->address) {
+       case RTQ6056_REG_SHUNTVOLT:
+               /* VSHUNT lsb  2.5uV */
+               *val = 2500;
+               *val2 = 1000000;
+               return IIO_VAL_FRACTIONAL;
+       case RTQ6056_REG_BUSVOLT:
+               /* VBUS lsb 1.25mV */
+               *val = 1250;
+               *val2 = 1000;
+               return IIO_VAL_FRACTIONAL;
+       case RTQ6056_REG_POWER:
+               /* Power lsb 25mW */
+               *val = 25;
+               return IIO_VAL_INT;
+       default:
+               return -EINVAL;
+       }
+}
+
+/*
+ * Conversion time in uS for channel VSHUNT and VBUS. The indices correspond
+ * with the bit value expected by the chip. And it can be found at
+ * https://www.richtek.com/assets/product_file/RTQ6056/DSQ6056-00.pdf
+ */
+static const int rtq6056_conv_time_list[] = {
+       139, 203, 269, 525, 1037, 2061, 4109, 8205,
+};
+
+static int rtq6056_adc_set_conv_time(struct rtq6056_priv *priv,
+                                    struct iio_chan_spec const *ch,
+                                    int val)
+{
+       struct regmap_field *rm_field;
+       unsigned int selector;
+       int *ct, ret;
+
+       if (val > 8205 || val < 139)
+               return -EINVAL;
+
+       if (ch->address == RTQ6056_REG_SHUNTVOLT) {
+               rm_field = priv->rm_fields[F_VSHUNTCT];
+               ct = &priv->vshuntct_us;
+       } else {
+               rm_field = priv->rm_fields[F_VBUSCT];
+               ct = &priv->vbusct_us;
+       }
+
+       selector = find_closest(val, rtq6056_conv_time_list,
+                               ARRAY_SIZE(rtq6056_conv_time_list));
+
+       ret = regmap_field_write(rm_field, selector);
+       if (ret)
+               return ret;
+
+       *ct = rtq6056_conv_time_list[selector];
+
+       return 0;
+}
+
+/*
+ * Available averaging rate for rtq6056. The indices correspond with the bit
+ * value expected by the chip. And it can be found at
+ * https://www.richtek.com/assets/product_file/RTQ6056/DSQ6056-00.pdf
+ */
+static const int rtq6056_avg_sample_list[] = {
+       1, 4, 16, 64, 128, 256, 512, 1024,
+};
+
+static int rtq6056_adc_set_average(struct rtq6056_priv *priv, int val)
+{
+       unsigned int selector;
+       int ret;
+
+       if (val > 1024 || val < 1)
+               return -EINVAL;
+
+       selector = find_closest(val, rtq6056_avg_sample_list,
+                               ARRAY_SIZE(rtq6056_avg_sample_list));
+
+       ret = regmap_field_write(priv->rm_fields[F_AVG], selector);
+       if (ret)
+               return ret;
+
+       priv->avg_sample = rtq6056_avg_sample_list[selector];
+
+       return 0;
+}
+
+static int rtq6056_adc_get_sample_freq(struct rtq6056_priv *priv, int *val)
+{
+       int sample_time;
+
+       sample_time = priv->vshuntct_us + priv->vbusct_us;
+       sample_time *= priv->avg_sample;
+
+       *val = DIV_ROUND_UP(1000000, sample_time);
+
+       return IIO_VAL_INT;
+}
+
+static int rtq6056_adc_read_raw(struct iio_dev *indio_dev,
+                               struct iio_chan_spec const *chan, int *val,
+                               int *val2, long mask)
+{
+       struct rtq6056_priv *priv = iio_priv(indio_dev);
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+               return rtq6056_adc_read_channel(priv, chan, val);
+       case IIO_CHAN_INFO_SCALE:
+               return rtq6056_adc_read_scale(chan, val, val2);
+       case IIO_CHAN_INFO_INT_TIME:
+               if (chan->address == RTQ6056_REG_SHUNTVOLT)
+                       *val = priv->vshuntct_us;
+               else
+                       *val = priv->vbusct_us;
+
+               return IIO_VAL_INT;
+       case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+               *val = priv->avg_sample;
+               return IIO_VAL_INT;
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               return rtq6056_adc_get_sample_freq(priv, val);
+       default:
+               return -EINVAL;
+       }
+}
+
+static int rtq6056_adc_read_avail(struct iio_dev *indio_dev,
+                                 struct iio_chan_spec const *chan,
+                                 const int **vals, int *type, int *length,
+                                 long mask)
+{
+       switch (mask) {
+       case IIO_CHAN_INFO_INT_TIME:
+               *vals = rtq6056_conv_time_list;
+               *type = IIO_VAL_INT;
+               *length = ARRAY_SIZE(rtq6056_conv_time_list);
+               return IIO_AVAIL_LIST;
+       case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+               *vals = rtq6056_avg_sample_list;
+               *type = IIO_VAL_INT;
+               *length = ARRAY_SIZE(rtq6056_avg_sample_list);
+               return IIO_AVAIL_LIST;
+       default:
+               return -EINVAL;
+       }
+}
+
+static int rtq6056_adc_write_raw(struct iio_dev *indio_dev,
+                                struct iio_chan_spec const *chan, int val,
+                                int val2, long mask)
+{
+       struct rtq6056_priv *priv = iio_priv(indio_dev);
+
+       if (iio_buffer_enabled(indio_dev))
+               return -EBUSY;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_INT_TIME:
+               return rtq6056_adc_set_conv_time(priv, chan, val);
+       case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+               return rtq6056_adc_set_average(priv, val);
+       default:
+               return -EINVAL;
+       }
+}
+
+static const char *rtq6056_channel_labels[RTQ6056_MAX_CHANNEL] = {
+       [RTQ6056_CH_VSHUNT] = "Vshunt",
+       [RTQ6056_CH_VBUS] = "Vbus",
+       [RTQ6056_CH_POWER] = "Power",
+       [RTQ6056_CH_CURRENT] = "Current",
+};
+
+static int rtq6056_adc_read_label(struct iio_dev *indio_dev,
+                                 struct iio_chan_spec const *chan,
+                                 char *label)
+{
+       return sysfs_emit(label, "%s\n", rtq6056_channel_labels[chan->channel]);
+}
+
+static int rtq6056_set_shunt_resistor(struct rtq6056_priv *priv,
+                                     int resistor_uohm)
+{
+       unsigned int calib_val;
+       int ret;
+
+       if (resistor_uohm <= 0) {
+               dev_err(priv->dev, "Invalid resistor [%d]\n", resistor_uohm);
+               return -EINVAL;
+       }
+
+       /* calibration = 5120000 / (Rshunt (uOhm) * current lsb (1mA)) */
+       calib_val = 5120000 / resistor_uohm;
+       ret = regmap_write(priv->regmap, RTQ6056_REG_CALIBRATION, calib_val);
+       if (ret)
+               return ret;
+
+       priv->shunt_resistor_uohm = resistor_uohm;
+
+       return 0;
+}
+
+static ssize_t shunt_resistor_show(struct device *dev,
+                                  struct device_attribute *attr, char *buf)
+{
+       struct rtq6056_priv *priv = iio_priv(dev_to_iio_dev(dev));
+       int vals[2] = { priv->shunt_resistor_uohm, 1000000 };
+
+       return iio_format_value(buf, IIO_VAL_FRACTIONAL, 1, vals);
+}
+
+static ssize_t shunt_resistor_store(struct device *dev,
+                                   struct device_attribute *attr,
+                                   const char *buf, size_t len)
+{
+       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+       struct rtq6056_priv *priv = iio_priv(indio_dev);
+       int val, val_fract, ret;
+
+       if (iio_buffer_enabled(indio_dev))
+               return -EBUSY;
+
+       ret = iio_str_to_fixpoint(buf, 100000, &val, &val_fract);
+       if (ret)
+               return ret;
+
+       ret = rtq6056_set_shunt_resistor(priv, val * 1000000 + val_fract);
+       if (ret)
+               return ret;
+
+       return len;
+}
+
+static IIO_DEVICE_ATTR_RW(shunt_resistor, 0);
+
+static struct attribute *rtq6056_attributes[] = {
+       &iio_dev_attr_shunt_resistor.dev_attr.attr,
+       NULL
+};
+
+static const struct attribute_group rtq6056_attribute_group = {
+       .attrs = rtq6056_attributes,
+};
+
+static const struct iio_info rtq6056_info = {
+       .attrs = &rtq6056_attribute_group,
+       .read_raw = rtq6056_adc_read_raw,
+       .read_avail = rtq6056_adc_read_avail,
+       .write_raw = rtq6056_adc_write_raw,
+       .read_label = rtq6056_adc_read_label,
+};
+
+static irqreturn_t rtq6056_buffer_trigger_handler(int irq, void *p)
+{
+       struct iio_poll_func *pf = p;
+       struct iio_dev *indio_dev = pf->indio_dev;
+       struct rtq6056_priv *priv = iio_priv(indio_dev);
+       struct device *dev = priv->dev;
+       struct {
+               u16 vals[RTQ6056_MAX_CHANNEL];
+               int64_t timestamp;
+       } data;
+       unsigned int raw;
+       int i = 0, bit, ret;
+
+       memset(&data, 0, sizeof(data));
+
+       pm_runtime_get_sync(dev);
+
+       for_each_set_bit(bit, indio_dev->active_scan_mask, indio_dev->masklength) {
+               unsigned int addr = rtq6056_channels[bit].address;
+
+               ret = regmap_read(priv->regmap, addr, &raw);
+               if (ret)
+                       goto out;
+
+               data.vals[i++] = raw;
+       }
+
+       iio_push_to_buffers_with_timestamp(indio_dev, &data, iio_get_time_ns(indio_dev));
+
+out:
+       pm_runtime_mark_last_busy(dev);
+       pm_runtime_put(dev);
+
+       iio_trigger_notify_done(indio_dev->trig);
+
+       return IRQ_HANDLED;
+}
+
+static void rtq6056_remove(void *dev)
+{
+       pm_runtime_dont_use_autosuspend(dev);
+       pm_runtime_disable(dev);
+       pm_runtime_set_suspended(dev);
+}
+
+static bool rtq6056_is_readable_reg(struct device *dev, unsigned int reg)
+{
+       switch (reg) {
+       case RTQ6056_REG_CONFIG ... RTQ6056_REG_ALERTLIMIT:
+       case RTQ6056_REG_MANUFACTID ... RTQ6056_REG_DIEID:
+               return true;
+       default:
+               return false;
+       }
+}
+
+static bool rtq6056_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+       switch (reg) {
+       case RTQ6056_REG_CONFIG:
+       case RTQ6056_REG_CALIBRATION ... RTQ6056_REG_ALERTLIMIT:
+               return true;
+       default:
+               return false;
+       }
+}
+
+static const struct regmap_config rtq6056_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 16,
+       .val_format_endian = REGMAP_ENDIAN_BIG,
+       .max_register = RTQ6056_REG_DIEID,
+       .readable_reg = rtq6056_is_readable_reg,
+       .writeable_reg = rtq6056_is_writeable_reg,
+};
+
+static int rtq6056_probe(struct i2c_client *i2c)
+{
+       struct iio_dev *indio_dev;
+       struct rtq6056_priv *priv;
+       struct device *dev = &i2c->dev;
+       struct regmap *regmap;
+       unsigned int vendor_id, shunt_resistor_uohm;
+       int ret;
+
+       if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_WORD_DATA))
+               return -EOPNOTSUPP;
+
+       indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
+       if (!indio_dev)
+               return -ENOMEM;
+
+       priv = iio_priv(indio_dev);
+       priv->dev = dev;
+       priv->vshuntct_us = priv->vbusct_us = 1037;
+       priv->avg_sample = 1;
+       i2c_set_clientdata(i2c, priv);
+
+       regmap = devm_regmap_init_i2c(i2c, &rtq6056_regmap_config);
+       if (IS_ERR(regmap))
+               return dev_err_probe(dev, PTR_ERR(regmap),
+                                    "Failed to init regmap\n");
+
+       priv->regmap = regmap;
+
+       ret = regmap_read(regmap, RTQ6056_REG_MANUFACTID, &vendor_id);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Failed to get manufacturer info\n");
+
+       if (vendor_id != RTQ6056_VENDOR_ID)
+               return dev_err_probe(dev, -ENODEV,
+                                    "Invalid vendor id 0x%04x\n", vendor_id);
+
+       ret = devm_regmap_field_bulk_alloc(dev, regmap, priv->rm_fields,
+                                          rtq6056_reg_fields, F_MAX_FIELDS);
+       if (ret)
+               return dev_err_probe(dev, ret, "Failed to init regmap field\n");
+
+       /*
+        * By default, configure average sample as 1, bus and shunt conversion
+        * timea as 1037 microsecond, and operating mode to all on.
+        */
+       ret = regmap_write(regmap, RTQ6056_REG_CONFIG, RTQ6056_DEFAULT_CONFIG);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Failed to enable continuous sensing\n");
+
+       pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC);
+       pm_runtime_use_autosuspend(dev);
+       pm_runtime_set_active(dev);
+       pm_runtime_mark_last_busy(dev);
+       pm_runtime_enable(dev);
+
+       ret = devm_add_action_or_reset(dev, rtq6056_remove, dev);
+       if (ret)
+               return ret;
+
+       /* By default, use 2000 micro-ohm resistor */
+       shunt_resistor_uohm = 2000;
+       device_property_read_u32(dev, "shunt-resistor-micro-ohms",
+                                &shunt_resistor_uohm);
+
+       ret = rtq6056_set_shunt_resistor(priv, shunt_resistor_uohm);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Failed to init shunt resistor\n");
+
+       indio_dev->name = "rtq6056";
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->channels = rtq6056_channels;
+       indio_dev->num_channels = ARRAY_SIZE(rtq6056_channels);
+       indio_dev->info = &rtq6056_info;
+
+       ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
+                                             rtq6056_buffer_trigger_handler,
+                                             NULL);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Failed to allocate iio trigger buffer\n");
+
+       return devm_iio_device_register(dev, indio_dev);
+}
+
+static int rtq6056_runtime_suspend(struct device *dev)
+{
+       struct rtq6056_priv *priv = dev_get_drvdata(dev);
+
+       /* Configure to shutdown mode */
+       return regmap_field_write(priv->rm_fields[F_OPMODE], 0);
+}
+
+static int rtq6056_runtime_resume(struct device *dev)
+{
+       struct rtq6056_priv *priv = dev_get_drvdata(dev);
+       int sample_rdy_time_us, ret;
+
+       ret = regmap_field_write(priv->rm_fields[F_OPMODE], RTQ6056_CONT_ALLON);
+       if (ret)
+               return ret;
+
+       sample_rdy_time_us = priv->vbusct_us + priv->vshuntct_us;
+       sample_rdy_time_us *= priv->avg_sample;
+
+       usleep_range(sample_rdy_time_us, sample_rdy_time_us + 100);
+
+       return 0;
+}
+
+static const struct dev_pm_ops rtq6056_pm_ops = {
+       RUNTIME_PM_OPS(rtq6056_runtime_suspend, rtq6056_runtime_resume, NULL)
+};
+
+static const struct of_device_id rtq6056_device_match[] = {
+       { .compatible = "richtek,rtq6056" },
+       {}
+};
+MODULE_DEVICE_TABLE(of, rtq6056_device_match);
+
+static struct i2c_driver rtq6056_driver = {
+       .driver = {
+               .name = "rtq6056",
+               .of_match_table = rtq6056_device_match,
+               .pm = pm_ptr(&rtq6056_pm_ops),
+       },
+       .probe_new = rtq6056_probe,
+};
+module_i2c_driver(rtq6056_driver);
+
+MODULE_AUTHOR("ChiYuan Huang <[email protected]>");
+MODULE_DESCRIPTION("Richtek RTQ6056 Driver");
+MODULE_LICENSE("GPL v2");
--

Quoted 2 lines

2.7.4

--
With Best Regards,
Andy Shevchenko

Andy Shevchenko <[email protected]> 於 2022年7月5日 週二 清晨5:18寫道：

Quoted 1 line · cy_huang

Quoted 2 lines

With a fixed kernel version (it may not be a stable version, we are now at v5.19 cycle, and it can't be either this cycle),

Do I need to submit v4 with the latest kernel?
Any misunderstanding?

Quoted 1 line

Reviewed-by Andy Shevchenko <[email protected]>

Quoted 2 lines · ChiYuan Huang

Andy Shevchenko <[email protected]> 於 2022年7月5日 週二 清晨5:18寫道：

Quoted 1 line · cy_huang

First of all, please remove the noise in the replies and leave only the necessary context. Respect other mail readers / commenters. (In case you wonder why I didn't follow this rule when given my tag, this is done in a way that I cited full code to show explicitly on what I have given the tag).

...

Quoted 4 lines

Quoted 2 lines

With a fixed kernel version (it may not be a stable version, we are now at v5.19 cycle, and it can't be either this cycle),

Do I need to submit v4 with the latest kernel?
Any misunderstanding?

Quoted 1 line

Quoted 1 line

Reviewed-by Andy Shevchenko <[email protected]>