iio: imu: st_lsm6dsx: add support for accel/gyro unit of lsm9ds1

The LSM9DS1's accelerometer / gyroscope unit and it's magnetometer (separately
supported in iio/magnetometer/st_magn*) are located on a separate i2c addresses
on the bus.

For the datasheet, see https://www.st.com/resource/en/datasheet/lsm9ds1.pdf

Treat it just like the LSM6* devices and, despite it's name, hook it up
to the st_lsm6dsx driver, using it's basic functionality.

accelerometer and gyroscope are not independently clocked. It runs at the gyro
frequencies if both are enabled, see chapter 7.12 of the datasheet.
We could have handled this as a single IIO device but we have split
it up to be more consistent with the other more flexible devices.

Despite supporting and testing the LSM9DS1, we call the gyro channels
iio_chan_spec struct "st_lsm6ds0_gyro_channels" because the register
description is equal. This suggests that supporting LSM6DS0 should be
trivial to do.

Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/st_lsm6dsx/Kconfig

@@ -12,7 +12,7 @@ config IIO_ST_LSM6DSX
 	  Say yes here to build support for STMicroelectronics LSM6DSx imu
 	  sensor. Supported devices: lsm6ds3, lsm6ds3h, lsm6dsl, lsm6dsm,
 	  ism330dlc, lsm6dso, lsm6dsox, asm330lhh, lsm6dsr, lsm6ds3tr-c,
-	  ism330dhcx
+	  ism330dhcx and the accelerometer/gyroscope of lsm9ds1.
 
 	  To compile this driver as a module, choose M here: the module
 	  will be called st_lsm6dsx.

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h

@@ -24,6 +24,7 @@
 #define ST_LSM6DSR_DEV_NAME	"lsm6dsr"
 #define ST_LSM6DS3TRC_DEV_NAME	"lsm6ds3tr-c"
 #define ST_ISM330DHCX_DEV_NAME	"ism330dhcx"
+#define ST_LSM9DS1_DEV_NAME	"lsm9ds1-imu"
 
 enum st_lsm6dsx_hw_id {
 	ST_LSM6DS3_ID,
@@ -37,6 +38,7 @@ enum st_lsm6dsx_hw_id {
 	ST_LSM6DSR_ID,
 	ST_LSM6DS3TRC_ID,
 	ST_ISM330DHCX_ID,
+	ST_LSM9DS1_ID,
 	ST_LSM6DSX_MAX_ID,
 };
 

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c

@@ -10,6 +10,8 @@
  * +-125/+-245/+-500/+-1000/+-2000 dps
  * LSM6DSx series has an integrated First-In-First-Out (FIFO) buffer
  * allowing dynamic batching of sensor data.
+ * LSM9DSx series is similar but includes an additional magnetometer, handled
+ * by a different driver.
  *
  * Supported sensors:
  * - LSM6DS3:
@@ -30,6 +32,13 @@
  *   - Gyroscope supported full-scale [dps]: +-125/+-245/+-500/+-1000/+-2000
  *   - FIFO size: 3KB
  *
+ * - LSM9DS1:
+ *   - Accelerometer supported ODR [Hz]: 10, 50, 119, 238, 476, 952
+ *   - Accelerometer supported full-scale [g]: +-2/+-4/+-8/+-16
+ *   - Gyroscope supported ODR [Hz]: 15, 60, 119, 238, 476, 952
+ *   - Gyroscope supported full-scale [dps]: +-245/+-500/+-2000
+ *   - FIFO size: 32
+ *
  * Copyright 2016 STMicroelectronics Inc.
  *
  * Lorenzo Bianconi <lorenzo.bianconi@st.com>
@@ -70,7 +79,85 @@ static const struct iio_chan_spec st_lsm6dsx_gyro_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(3),
 };
 
+static const struct iio_chan_spec st_lsm6ds0_gyro_channels[] = {
+	ST_LSM6DSX_CHANNEL(IIO_ANGL_VEL, 0x18, IIO_MOD_X, 0),
+	ST_LSM6DSX_CHANNEL(IIO_ANGL_VEL, 0x1a, IIO_MOD_Y, 1),
+	ST_LSM6DSX_CHANNEL(IIO_ANGL_VEL, 0x1c, IIO_MOD_Z, 2),
+	IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
 static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
+	{
+		.wai = 0x68,
+		.int1_addr = 0x0c,
+		.int2_addr = 0x0d,
+		.reset_addr = 0x22,
+		.max_fifo_size = 32,
+		.id = {
+			{
+				.hw_id = ST_LSM9DS1_ID,
+				.name = ST_LSM9DS1_DEV_NAME,
+			},
+		},
+		.channels = {
+			[ST_LSM6DSX_ID_ACC] = {
+				.chan = st_lsm6dsx_acc_channels,
+				.len = ARRAY_SIZE(st_lsm6dsx_acc_channels),
+			},
+			[ST_LSM6DSX_ID_GYRO] = {
+				.chan = st_lsm6ds0_gyro_channels,
+				.len = ARRAY_SIZE(st_lsm6ds0_gyro_channels),
+			},
+		},
+		.odr_table = {
+			[ST_LSM6DSX_ID_ACC] = {
+				.reg = {
+					.addr = 0x20,
+					.mask = GENMASK(7, 5),
+				},
+				.odr_avl[0] = {  10, 0x01 },
+				.odr_avl[1] = {  50, 0x02 },
+				.odr_avl[2] = { 119, 0x03 },
+				.odr_avl[3] = { 238, 0x04 },
+				.odr_avl[4] = { 476, 0x05 },
+				.odr_avl[5] = { 952, 0x06 },
+			},
+			[ST_LSM6DSX_ID_GYRO] = {
+				.reg = {
+					.addr = 0x10,
+					.mask = GENMASK(7, 5),
+				},
+				.odr_avl[0] = {  15, 0x01 },
+				.odr_avl[1] = {  60, 0x02 },
+				.odr_avl[2] = { 119, 0x03 },
+				.odr_avl[3] = { 238, 0x04 },
+				.odr_avl[4] = { 476, 0x05 },
+				.odr_avl[5] = { 952, 0x06 },
+			},
+		},
+		.fs_table = {
+			[ST_LSM6DSX_ID_ACC] = {
+				.reg = {
+					.addr = 0x20,
+					.mask = GENMASK(4, 3),
+				},
+				.fs_avl[0] = {  599, 0x0 },
+				.fs_avl[1] = { 1197, 0x2 },
+				.fs_avl[2] = { 2394, 0x3 },
+				.fs_avl[3] = { 4788, 0x1 },
+			},
+			[ST_LSM6DSX_ID_GYRO] = {
+				.reg = {
+					.addr = 0x10,
+					.mask = GENMASK(4, 3),
+				},
+				.fs_avl[0] = { IIO_DEGREE_TO_RAD(245), 0x0 },
+				.fs_avl[1] = { IIO_DEGREE_TO_RAD(500), 0x1 },
+				.fs_avl[2] = { IIO_DEGREE_TO_RAD(0), 0x2 },
+				.fs_avl[3] = { IIO_DEGREE_TO_RAD(2000), 0x3 },
+			},
+		},
+	},
 	{
 		.wai = 0x69,
 		.int1_addr = 0x0d,

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c

@@ -83,6 +83,10 @@ static const struct of_device_id st_lsm6dsx_i2c_of_match[] = {
 		.compatible = "st,ism330dhcx",
 		.data = (void *)ST_ISM330DHCX_ID,
 	},
+	{
+		.compatible = "st,lsm9ds1-imu",
+		.data = (void *)ST_LSM9DS1_ID,
+	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, st_lsm6dsx_i2c_of_match);
@@ -99,6 +103,7 @@ static const struct i2c_device_id st_lsm6dsx_i2c_id_table[] = {
 	{ ST_LSM6DSR_DEV_NAME, ST_LSM6DSR_ID },
 	{ ST_LSM6DS3TRC_DEV_NAME, ST_LSM6DS3TRC_ID },
 	{ ST_ISM330DHCX_DEV_NAME, ST_ISM330DHCX_ID },
+	{ ST_LSM9DS1_DEV_NAME, ST_LSM9DS1_ID },
 	{},
 };
 MODULE_DEVICE_TABLE(i2c, st_lsm6dsx_i2c_id_table);

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c

@@ -83,6 +83,10 @@ static const struct of_device_id st_lsm6dsx_spi_of_match[] = {
 		.compatible = "st,ism330dhcx",
 		.data = (void *)ST_ISM330DHCX_ID,
 	},
+	{
+		.compatible = "st,lsm9ds1-imu",
+		.data = (void *)ST_LSM9DS1_ID,
+	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, st_lsm6dsx_spi_of_match);
@@ -99,6 +103,7 @@ static const struct spi_device_id st_lsm6dsx_spi_id_table[] = {
 	{ ST_LSM6DSR_DEV_NAME, ST_LSM6DSR_ID },
 	{ ST_LSM6DS3TRC_DEV_NAME, ST_LSM6DS3TRC_ID },
 	{ ST_ISM330DHCX_DEV_NAME, ST_ISM330DHCX_ID },
+	{ ST_LSM9DS1_DEV_NAME, ST_LSM9DS1_ID },
 	{},
 };
 MODULE_DEVICE_TABLE(spi, st_lsm6dsx_spi_id_table);