drivers: iio: accel: Add support for ADXL359 device

Add support for ADXL359 device in already existing ADXL355 driver.

Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adxl359.pdfSigned-off-by: Ramona Bolboaca <ramona.bolboaca@analog.com>
Link: https://lore.kernel.org/r/20221031105129.47740-4-ramona.bolboaca@analog.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/accel/adxl355.h

@@ -10,12 +10,30 @@
 
 #include <linux/regmap.h>
 
+enum adxl355_device_type {
+	ADXL355,
+	ADXL359,
+};
+
+struct adxl355_fractional_type {
+	int integer;
+	int decimal;
+};
+
 struct device;
 
+struct adxl355_chip_info {
+	const char			*name;
+	u8				part_id;
+	struct adxl355_fractional_type	accel_scale;
+	struct adxl355_fractional_type	temp_offset;
+};
+
 extern const struct regmap_access_table adxl355_readable_regs_tbl;
 extern const struct regmap_access_table adxl355_writeable_regs_tbl;
+extern const struct adxl355_chip_info adxl35x_chip_info[];
 
 int adxl355_core_probe(struct device *dev, struct regmap *regmap,
-		       const char *name);
+		       const struct adxl355_chip_info *chip_info);
 
 #endif /* _ADXL355_H_ */

drivers/iio/accel/adxl355_core.c

@@ -60,6 +60,7 @@
 #define ADXL355_DEVID_AD_VAL		0xAD
 #define ADXL355_DEVID_MST_VAL		0x1D
 #define ADXL355_PARTID_VAL		0xED
+#define ADXL359_PARTID_VAL		0xE9
 #define ADXL355_RESET_CODE		0x52
 
 static const struct regmap_range adxl355_read_reg_range[] = {
@@ -83,6 +84,60 @@ const struct regmap_access_table adxl355_writeable_regs_tbl = {
 };
 EXPORT_SYMBOL_NS_GPL(adxl355_writeable_regs_tbl, IIO_ADXL355);
 
+const struct adxl355_chip_info adxl35x_chip_info[] = {
+	[ADXL355] = {
+		.name = "adxl355",
+		.part_id = ADXL355_PARTID_VAL,
+		/*
+		 * At +/- 2g with 20-bit resolution, scale is given in datasheet
+		 * as 3.9ug/LSB = 0.0000039 * 9.80665 = 0.00003824593 m/s^2.
+		 */
+		.accel_scale = {
+			.integer = 0,
+			.decimal = 38245,
+		},
+		/*
+		 * The datasheet defines an intercept of 1885 LSB at 25 degC
+		 * and a slope of -9.05 LSB/C. The following formula can be used
+		 * to find the temperature:
+		 * Temp = ((RAW - 1885)/(-9.05)) + 25 but this doesn't follow
+		 * the format of the IIO which is Temp = (RAW + OFFSET) * SCALE.
+		 * Hence using some rearranging we get the scale as -110.497238
+		 * and offset as -2111.25.
+		 */
+		.temp_offset = {
+			.integer =  -2111,
+			.decimal = 250000,
+		},
+	},
+	[ADXL359] = {
+		.name = "adxl359",
+		.part_id = ADXL359_PARTID_VAL,
+		/*
+		 * At +/- 10g with 20-bit resolution, scale is given in datasheet
+		 * as 19.5ug/LSB = 0.0000195 * 9.80665 = 0.0.00019122967 m/s^2.
+		 */
+		.accel_scale = {
+			.integer = 0,
+			.decimal = 191229,
+		},
+		/*
+		 * The datasheet defines an intercept of 1852 LSB at 25 degC
+		 * and a slope of -9.05 LSB/C. The following formula can be used
+		 * to find the temperature:
+		 * Temp = ((RAW - 1852)/(-9.05)) + 25 but this doesn't follow
+		 * the format of the IIO which is Temp = (RAW + OFFSET) * SCALE.
+		 * Hence using some rearranging we get the scale as -110.497238
+		 * and offset as -2079.25.
+		 */
+		.temp_offset = {
+			.integer = -2079,
+			.decimal = 250000,
+		},
+	},
+};
+EXPORT_SYMBOL_NS_GPL(adxl35x_chip_info, IIO_ADXL355);
+
 enum adxl355_op_mode {
 	ADXL355_MEASUREMENT,
 	ADXL355_STANDBY,
@@ -162,6 +217,7 @@ static const struct adxl355_chan_info adxl355_chans[] = {
 };
 
 struct adxl355_data {
+	const struct adxl355_chip_info *chip_info;
 	struct regmap *regmap;
 	struct device *dev;
 	struct mutex lock; /* lock to protect op_mode */
@@ -456,33 +512,25 @@ static int adxl355_read_raw(struct iio_dev *indio_dev,
 
 	case IIO_CHAN_INFO_SCALE:
 		switch (chan->type) {
-		/*
-		 * The datasheet defines an intercept of 1885 LSB at 25 degC
-		 * and a slope of -9.05 LSB/C. The following formula can be used
-		 * to find the temperature:
-		 * Temp = ((RAW - 1885)/(-9.05)) + 25 but this doesn't follow
-		 * the format of the IIO which is Temp = (RAW + OFFSET) * SCALE.
-		 * Hence using some rearranging we get the scale as -110.497238
-		 * and offset as -2111.25.
-		 */
 		case IIO_TEMP:
+			/*
+			 * Temperature scale is -110.497238.
+			 * See the detailed explanation in adxl35x_chip_info
+			 * definition above.
+			 */
 			*val = -110;
 			*val2 = 497238;
 			return IIO_VAL_INT_PLUS_MICRO;
-		/*
-		 * At +/- 2g with 20-bit resolution, scale is given in datasheet
-		 * as 3.9ug/LSB = 0.0000039 * 9.80665 = 0.00003824593 m/s^2.
-		 */
 		case IIO_ACCEL:
-			*val = 0;
-			*val2 = 38245;
+			*val = data->chip_info->accel_scale.integer;
+			*val2 = data->chip_info->accel_scale.decimal;
 			return IIO_VAL_INT_PLUS_NANO;
 		default:
 			return -EINVAL;
 		}
 	case IIO_CHAN_INFO_OFFSET:
-		*val = -2111;
-		*val2 = 250000;
+		*val = data->chip_info->temp_offset.integer;
+		*val2 = data->chip_info->temp_offset.decimal;
 		return IIO_VAL_INT_PLUS_MICRO;
 	case IIO_CHAN_INFO_CALIBBIAS:
 		*val = sign_extend32(data->calibbias[chan->address], 15);
@@ -705,7 +753,7 @@ static int adxl355_probe_trigger(struct iio_dev *indio_dev, int irq)
 }
 
 int adxl355_core_probe(struct device *dev, struct regmap *regmap,
-		       const char *name)
+		       const struct adxl355_chip_info *chip_info)
 {
 	struct adxl355_data *data;
 	struct iio_dev *indio_dev;
@@ -720,9 +768,10 @@ int adxl355_core_probe(struct device *dev, struct regmap *regmap,
 	data->regmap = regmap;
 	data->dev = dev;
 	data->op_mode = ADXL355_STANDBY;
+	data->chip_info = chip_info;
 	mutex_init(&data->lock);
 
-	indio_dev->name = name;
+	indio_dev->name = chip_info->name;
 	indio_dev->info = &adxl355_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->channels = adxl355_channels;

drivers/iio/accel/adxl355_i2c.c

@@ -23,6 +23,20 @@ static const struct regmap_config adxl355_i2c_regmap_config = {
 static int adxl355_i2c_probe(struct i2c_client *client)
 {
 	struct regmap *regmap;
+	const struct adxl355_chip_info *chip_data;
+	const struct i2c_device_id *adxl355;
+
+	chip_data = device_get_match_data(&client->dev);
+	if (!chip_data) {
+		adxl355 = to_i2c_driver(client->dev.driver)->id_table;
+		if (!adxl355)
+			return -EINVAL;
+
+		chip_data = (void *)i2c_match_id(adxl355, client)->driver_data;
+
+		if (!chip_data)
+			return -EINVAL;
+	}
 
 	regmap = devm_regmap_init_i2c(client, &adxl355_i2c_regmap_config);
 	if (IS_ERR(regmap)) {
@@ -32,17 +46,19 @@ static int adxl355_i2c_probe(struct i2c_client *client)
 		return PTR_ERR(regmap);
 	}
 
-	return adxl355_core_probe(&client->dev, regmap, client->name);
+	return adxl355_core_probe(&client->dev, regmap, chip_data);
 }
 
 static const struct i2c_device_id adxl355_i2c_id[] = {
-	{ "adxl355", 0 },
+	{ "adxl355", (kernel_ulong_t)&adxl35x_chip_info[ADXL355] },
+	{ "adxl359", (kernel_ulong_t)&adxl35x_chip_info[ADXL359] },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, adxl355_i2c_id);
 
 static const struct of_device_id adxl355_of_match[] = {
-	{ .compatible = "adi,adxl355" },
+	{ .compatible = "adi,adxl355", .data = &adxl35x_chip_info[ADXL355] },
+	{ .compatible = "adi,adxl359", .data = &adxl35x_chip_info[ADXL359] },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, adxl355_of_match);

drivers/iio/accel/adxl355_spi.c

@@ -9,6 +9,7 @@
 #include <linux/mod_devicetable.h>
 #include <linux/regmap.h>
 #include <linux/spi/spi.h>
+#include <linux/property.h>
 
 #include "adxl355.h"
 
@@ -24,9 +25,17 @@ static const struct regmap_config adxl355_spi_regmap_config = {
 
 static int adxl355_spi_probe(struct spi_device *spi)
 {
-	const struct spi_device_id *id = spi_get_device_id(spi);
+	const struct adxl355_chip_info *chip_data;
 	struct regmap *regmap;
 
+	chip_data = device_get_match_data(&spi->dev);
+	if (!chip_data) {
+		chip_data = (void *)spi_get_device_id(spi)->driver_data;
+
+		if (!chip_data)
+			return -EINVAL;
+	}
+
 	regmap = devm_regmap_init_spi(spi, &adxl355_spi_regmap_config);
 	if (IS_ERR(regmap)) {
 		dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
@@ -35,17 +44,19 @@ static int adxl355_spi_probe(struct spi_device *spi)
 		return PTR_ERR(regmap);
 	}
 
-	return adxl355_core_probe(&spi->dev, regmap, id->name);
+	return adxl355_core_probe(&spi->dev, regmap, chip_data);
 }
 
 static const struct spi_device_id adxl355_spi_id[] = {
-	{ "adxl355", 0 },
+	{ "adxl355", (kernel_ulong_t)&adxl35x_chip_info[ADXL355] },
+	{ "adxl359", (kernel_ulong_t)&adxl35x_chip_info[ADXL359] },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, adxl355_spi_id);
 
 static const struct of_device_id adxl355_of_match[] = {
-	{ .compatible = "adi,adxl355" },
+	{ .compatible = "adi,adxl355", .data = &adxl35x_chip_info[ADXL355] },
+	{ .compatible = "adi,adxl359", .data = &adxl35x_chip_info[ADXL359] },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, adxl355_of_match);