Add support for Microchip Technology's MCP3426/7/8 ADC

This patch extends previous mcp3422 driver to support missing members of the family mcp3426/7/8.

Signed-off-by Angelo Compagnucci <[email protected]>

---
drivers/iio/adc/Kconfig | 7 ++--
drivers/iio/adc/mcp3422.c | 84
++++++++++++++++++++++++++++++-----------------

2 files changed, 57 insertions(+), 34 deletions(-)

drivers/iio/adc/Kconfig +0 -0

index 5553206..246d9d2 100644
@@ -146,11 +146,12 @@ config MCP320X
 	  called mcp320x.
 

config MCP3422

drivers/iio/adc/Kconfig +1 -1

-	tristate "Microchip Technology MCP3422/3/4 driver"
+	tristate "Microchip Technology MCP3422/3/4/6/7/8 driver"

depends on I2C
help

drivers/iio/adc/Kconfig +3 -2

-	  Say yes here to build support for Microchip Technology's MCP3422,
-	  MCP3423 or MCP3424 analog to digital converters.
+	  Say yes here to build support for Microchip Technology's
+	  MCP3422, MCP3423, MCP3424, MCP3426, MCP3427 or MCP3428 
+	  analog to digital converters.

	  This driver can also be built as a module. If so, the module will be
	  called mcp3422.

drivers/iio/adc/mcp3422.c +2 -1

index 47dcb34..76e206a 100644
@@ -1,10 +1,11 @@
 /*
- * mcp3422.c - driver for the Microchip mcp3422/3/4 chip family
+ * mcp3422.c - driver for the Microchip mcp3422/3/4/6/7/8 chip family
 *
 * Copyright (C) 2013, Angelo Compagnucci
 * Author: Angelo Compagnucci <[email protected]>
 *
 * Datasheet: http://ww1.microchip.com/downloads/en/devicedoc/22088b.pdf
+ *           

http://ww1.microchip.com/downloads/en/DeviceDoc/22226a.pdf
*
* This driver exports the value of analog input voltage to sysfs, the
* voltage unit is nV.

drivers/iio/adc/mcp3422.c +12 -12

@@ -26,18 +27,18 @@
 #include <linux/iio/sysfs.h>
 
 /* Masks */
-#define MCP3422_CHANNEL_MASK	0x60
-#define MCP3422_PGA_MASK	0x03
-#define MCP3422_SRATE_MASK	0x0C
-#define MCP3422_SRATE_240	0x0
-#define MCP3422_SRATE_60	0x1
-#define MCP3422_SRATE_15	0x2
-#define MCP3422_SRATE_3	0x3
-#define MCP3422_PGA_1	0
-#define MCP3422_PGA_2	1
-#define MCP3422_PGA_4	2
-#define MCP3422_PGA_8	3
-#define MCP3422_CONT_SAMPLING	0x10
+#define MCP3422_CHANNEL_MASK    0x60
+#define MCP3422_PGA_MASK        0x03
+#define MCP3422_SRATE_MASK      0x0C
+#define MCP3422_SRATE_240       0x0
+#define MCP3422_SRATE_60        0x1
+#define MCP3422_SRATE_15        0x2
+#define MCP3422_SRATE_3         0x3
+#define MCP3422_PGA_1           0
+#define MCP3422_PGA_2           1
+#define MCP3422_PGA_4           2
+#define MCP3422_PGA_8           3
+#define MCP3422_CONT_SAMPLING   0x10
 
 #define MCP3422_CHANNEL(config)	(((config) & MCP3422_CHANNEL_MASK) >>
 5)

#define MCP3422_PGA(config) ((config) & MCP3422_PGA_MASK)

drivers/iio/adc/mcp3422.c +0 -1

@@ -65,7 +66,6 @@ static const u32 rates_to_lsb[] = {1000000, 250000,
 62500, 15625};
 *  rates_to_lsb[sample_rate] / (1 << pga);
 *  pga is 1 for 0, 2
 */
-
 static const int mcp3422_scales[4][4] = {
 	{ 1000000, 250000, 62500, 15625 },

	{ 500000 , 125000, 31250, 7812 },

drivers/iio/adc/mcp3422.c +1 -0

@@ -96,6 +96,7 @@ static const int mcp3422_sign_extend[4] = {
 /* Client data (each client gets its own) */
 struct mcp3422 {
 	struct i2c_client *i2c;
+	u8 id;
 	u8 config;
 	u8 pga[4];
 	struct mutex lock;

drivers/iio/adc/mcp3422.c +5 -5

-	if (sample_rate == MCP3422_SRATE_3) {
-		ret = i2c_master_recv(adc->i2c, buf, 4);
-		temp = buf[0] << 16 | buf[1] << 8 | buf[2];
-		*config = buf[3];
-	} else {
+	if (sample_rate != MCP3422_SRATE_3) {
 		ret = i2c_master_recv(adc->i2c, buf, 3);
 		temp = buf[0] << 8 | buf[1];
 		*config = buf[2];
+	} else {
+		ret = i2c_master_recv(adc->i2c, buf, 4);
+		temp = buf[0] << 16 | buf[1] << 8 | buf[2];
+		*config = buf[3];
 	}
 

	*value = sign_extend32(temp, mcp3422_sign_extend[sample_rate]);

drivers/iio/adc/mcp3422.c +1 -1

@@ -141,7 +142,7 @@ static int mcp3422_read(struct mcp3422 *adc, int
 *value, u8 *config)
 }
 
 static int mcp3422_read_channel(struct mcp3422 *adc,
-				struct iio_chan_spec const *channel, int *value)
+		struct iio_chan_spec const *channel, int *value)
 {
 	int ret;

	u8 config;

drivers/iio/adc/mcp3422.c +0 -0

 {
 	struct mcp3422 *adc = iio_priv(iio);

	int err;

drivers/iio/adc/mcp3422.c +15 -2

@@ -197,8 +198,8 @@ static int mcp3422_read_raw(struct iio_dev *iio,
 }
 
 static int mcp3422_write_raw(struct iio_dev *iio,
-			struct iio_chan_spec const *channel, int val1,
-			int val2, long mask)
+		struct iio_chan_spec const *channel, int val1,
+		int val2, long mask)
 {
 	struct mcp3422 *adc = iio_priv(iio);
 	u8 temp;

@@ -238,6 +239,8 @@ static int mcp3422_write_raw(struct iio_dev *iio,
 			temp = MCP3422_SRATE_15;
 			break;
 		case 3:
+			if (adc->id > 4)
+				return -EINVAL;
 			temp = MCP3422_SRATE_3;
 			break;
 		default:

@@ -271,6 +274,17 @@ static int mcp3422_write_raw_get_fmt(struct
 iio_dev *indio_dev,
 	}
 }
 
+static ssize_t mcp3422_show_samp_freq(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct mcp3422 *adc = iio_priv(dev_to_iio_dev(dev));
+
+	if (adc->id > 4)
+		return sprintf(buf, "240 60 15\n");
+
+	return sprintf(buf, "240 60 15 3\n");
+}
+
 static ssize_t mcp3422_show_scales(struct device *dev,
 		struct device_attribute *attr, char *buf)

{

drivers/iio/adc/mcp3422.c +3 -2

@@ -284,12 +298,13 @@ static ssize_t mcp3422_show_scales(struct device
 *dev,
 		mcp3422_scales[sample_rate][3]);
 }
 
-static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("240 60 15 3");
+static IIO_DEVICE_ATTR(sampling_frequency_available, S_IRUGO,
+		mcp3422_show_samp_freq, NULL, 0);
 static IIO_DEVICE_ATTR(in_voltage_scale_available, S_IRUGO,
 		mcp3422_show_scales, NULL, 0);
 
 static struct attribute *mcp3422_attributes[] = {
-	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
+	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 	&iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
 	NULL,

};

drivers/iio/adc/mcp3422.c +1 -1

@@ -303,7 +318,7 @@ static const struct iio_chan_spec
 mcp3422_channels[] = {
 	MCP3422_CHAN(1),
 };
 
-static const struct iio_chan_spec mcp3424_channels[] = {
+static const struct iio_chan_spec mcp3426_channels[] = {
 	MCP3422_CHAN(0),
 	MCP3422_CHAN(1),

	MCP3422_CHAN(2),

drivers/iio/adc/mcp3422.c +11 -4

@@ -335,6 +350,7 @@ static int mcp3422_probe(struct i2c_client *client,
 
 	adc = iio_priv(indio_dev);
 	adc->i2c = client;
+	adc->id = (u8)(id->driver_data);
 
 	mutex_init(&adc->lock);
 

@@ -343,15 +359,18 @@ static int mcp3422_probe(struct i2c_client
 *client,
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &mcp3422_info;
 
-	switch ((unsigned int)(id->driver_data)) {
+	switch (adc->id) {
 	case 2:
 	case 3:
+	case 6:
+	case 7:
 		indio_dev->channels = mcp3422_channels;
 		indio_dev->num_channels = ARRAY_SIZE(mcp3422_channels);
 		break;
 	case 4:
-		indio_dev->channels = mcp3424_channels;
-		indio_dev->num_channels = ARRAY_SIZE(mcp3424_channels);
+	case 8:
+		indio_dev->channels = mcp3426_channels;
+		indio_dev->num_channels = ARRAY_SIZE(mcp3426_channels);
 		break;
 	}

@@ -375,6 +394,9 @@ static const struct i2c_device_id mcp3422_id[] = {
 	{ "mcp3422", 2 },
 	{ "mcp3423", 3 },
 	{ "mcp3424", 4 },
+	{ "mcp3426", 6 },
+	{ "mcp3427", 7 },
+	{ "mcp3428", 8 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, mcp3422_id);

@@ -399,5 +421,5 @@ static struct i2c_driver mcp3422_driver = {
 module_i2c_driver(mcp3422_driver);
 
 MODULE_AUTHOR("Angelo Compagnucci <[email protected]>");
-MODULE_DESCRIPTION("Microchip mcp3422/3/4 driver");
+MODULE_DESCRIPTION("Microchip mcp3422/3/4/6/7/8 driver");
 MODULE_LICENSE("GPL v2");