[PATCH v4 3/3] iio: magnetometer: add ti tmag5273 driver

From: Gerald Loacker
Date: Tue Nov 29 2022 - 01:46:25 EST


Add support for TI TMAG5273 Low-Power Linear 3D Hall-Effect Sensor.
Additionally to temperature and magnetic X, Y and Z-axes the angle and
magnitude are reported.
The sensor is operating in continuous measurement mode and changes to sleep
mode if not used for 5 seconds.

Datasheet: https://www.ti.com/lit/gpn/tmag5273
Signed-off-by: Gerald Loacker <gerald.loacker@xxxxxxxxxxxxxx>
---
Changes in v4:
- Renamed struct iio_val_int_plus_micro members
- Simplified tmag5273_write_scale()
- Removed unnecessary '!= 0'
- Fixed regmap max_register
- Simplified tmag5273_read_device_property()
- Fixed some line breaks

Changes in v3:
- Added include <linux/bitfield.h>
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
- Added include <linux/bits.h>
- Removed <asm/unaligned.h>
- Added missing "static const" for tmag5273_avg_table
- Documented Device ID
- Fixed index of tmag5273_scale definition
- Clarify TMAG5273_MAG_CH_EN_X_Y_Z as an index
- Removed unnecessary print
- Introduced tmag5273_write_scale() and tmag5273_write_osr() helper
functions
- Use of match_string()
- Format

Changes in v2:
- Implemented suggestions from review and cleaned up probe function. This
results in changes all over the tmag5273.c code.
MAINTAINERS | 1 +
drivers/iio/magnetometer/Kconfig | 12 +
drivers/iio/magnetometer/Makefile | 2 +
drivers/iio/magnetometer/tmag5273.c | 731 ++++++++++++++++++++++++++++
4 files changed, 746 insertions(+)
create mode 100644 drivers/iio/magnetometer/tmag5273.c

diff --git a/MAINTAINERS b/MAINTAINERS
index ea7acec52f8b..9d20b5780051 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -20618,6 +20618,7 @@ M: Gerald Loacker <gerald.loacker@xxxxxxxxxxxxxx>
L: linux-iio@xxxxxxxxxxxxxxx
S: Maintained
F: Documentation/devicetree/bindings/iio/magnetometer/ti,tmag5273.yaml
+F: drivers/iio/magnetometer/tmag5273.c

TI TRF7970A NFC DRIVER
M: Mark Greer <mgreer@xxxxxxxxxxxxxxx>
diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig
index b91fc5e6a26e..467819335588 100644
--- a/drivers/iio/magnetometer/Kconfig
+++ b/drivers/iio/magnetometer/Kconfig
@@ -208,6 +208,18 @@ config SENSORS_RM3100_SPI
To compile this driver as a module, choose M here: the module
will be called rm3100-spi.

+config TI_TMAG5273
+ tristate "TI TMAG5273 Low-Power Linear 3D Hall-Effect Sensor"
+ depends on I2C
+ select REGMAP_I2C
+ help
+ Say Y here to add support for the TI TMAG5273 Low-Power
+ Linear 3D Hall-Effect Sensor.
+
+ This driver can also be compiled as a module.
+ To compile this driver as a module, choose M here: the module
+ will be called tmag5273.
+
config YAMAHA_YAS530
tristate "Yamaha YAS530 family of 3-Axis Magnetometers (I2C)"
depends on I2C
diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile
index b9f45b7fafc3..b1c784ea71c8 100644
--- a/drivers/iio/magnetometer/Makefile
+++ b/drivers/iio/magnetometer/Makefile
@@ -29,4 +29,6 @@ obj-$(CONFIG_SENSORS_RM3100) += rm3100-core.o
obj-$(CONFIG_SENSORS_RM3100_I2C) += rm3100-i2c.o
obj-$(CONFIG_SENSORS_RM3100_SPI) += rm3100-spi.o

+obj-$(CONFIG_TI_TMAG5273) += tmag5273.o
+
obj-$(CONFIG_YAMAHA_YAS530) += yamaha-yas530.o
diff --git a/drivers/iio/magnetometer/tmag5273.c b/drivers/iio/magnetometer/tmag5273.c
new file mode 100644
index 000000000000..d3579004cb58
--- /dev/null
+++ b/drivers/iio/magnetometer/tmag5273.c
@@ -0,0 +1,731 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for the TI TMAG5273 Low-Power Linear 3D Hall-Effect Sensor
+ *
+ * Copyright (C) 2022 WolfVision GmbH
+ *
+ * Author: Gerald Loacker <gerald.loacker@xxxxxxxxxxxxxx>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define TMAG5273_DEVICE_CONFIG_1 0x00
+#define TMAG5273_DEVICE_CONFIG_2 0x01
+#define TMAG5273_SENSOR_CONFIG_1 0x02
+#define TMAG5273_SENSOR_CONFIG_2 0x03
+#define TMAG5273_X_THR_CONFIG 0x04
+#define TMAG5273_Y_THR_CONFIG 0x05
+#define TMAG5273_Z_THR_CONFIG 0x06
+#define TMAG5273_T_CONFIG 0x07
+#define TMAG5273_INT_CONFIG_1 0x08
+#define TMAG5273_MAG_GAIN_CONFIG 0x09
+#define TMAG5273_MAG_OFFSET_CONFIG_1 0x0A
+#define TMAG5273_MAG_OFFSET_CONFIG_2 0x0B
+#define TMAG5273_I2C_ADDRESS 0x0C
+#define TMAG5273_DEVICE_ID 0x0D
+#define TMAG5273_MANUFACTURER_ID_LSB 0x0E
+#define TMAG5273_MANUFACTURER_ID_MSB 0x0F
+#define TMAG5273_T_MSB_RESULT 0x10
+#define TMAG5273_T_LSB_RESULT 0x11
+#define TMAG5273_X_MSB_RESULT 0x12
+#define TMAG5273_X_LSB_RESULT 0x13
+#define TMAG5273_Y_MSB_RESULT 0x14
+#define TMAG5273_Y_LSB_RESULT 0x15
+#define TMAG5273_Z_MSB_RESULT 0x16
+#define TMAG5273_Z_LSB_RESULT 0x17
+#define TMAG5273_CONV_STATUS 0x18
+#define TMAG5273_ANGLE_RESULT_MSB 0x19
+#define TMAG5273_ANGLE_RESULT_LSB 0x1A
+#define TMAG5273_MAGNITUDE_RESULT 0x1B
+#define TMAG5273_DEVICE_STATUS 0x1C
+
+#define TMAG5273_AUTOSLEEP_DELAY_MS 5000
+#define TMAG5273_MAX_AVERAGE 32
+
+/*
+ * bits in the TMAG5273_MANUFACTURER_ID_LSB / MSB register
+ * 16-bit unique manufacturer ID 0x49 / 0x54 = "TI"
+ */
+#define TMAG5273_MANUFACTURER_ID 0x5449
+
+/* bits in the TMAG5273_DEVICE_CONFIG_1 register */
+#define TMAG5273_AVG_MODE_MASK GENMASK(4, 2)
+#define TMAG5273_AVG_1_MODE FIELD_PREP(TMAG5273_AVG_MODE_MASK, 0)
+#define TMAG5273_AVG_2_MODE FIELD_PREP(TMAG5273_AVG_MODE_MASK, 1)
+#define TMAG5273_AVG_4_MODE FIELD_PREP(TMAG5273_AVG_MODE_MASK, 2)
+#define TMAG5273_AVG_8_MODE FIELD_PREP(TMAG5273_AVG_MODE_MASK, 3)
+#define TMAG5273_AVG_16_MODE FIELD_PREP(TMAG5273_AVG_MODE_MASK, 4)
+#define TMAG5273_AVG_32_MODE FIELD_PREP(TMAG5273_AVG_MODE_MASK, 5)
+
+/* bits in the TMAG5273_DEVICE_CONFIG_2 register */
+#define TMAG5273_OP_MODE_MASK GENMASK(1, 0)
+#define TMAG5273_OP_MODE_STANDBY FIELD_PREP(TMAG5273_OP_MODE_MASK, 0)
+#define TMAG5273_OP_MODE_SLEEP FIELD_PREP(TMAG5273_OP_MODE_MASK, 1)
+#define TMAG5273_OP_MODE_CONT FIELD_PREP(TMAG5273_OP_MODE_MASK, 2)
+#define TMAG5273_OP_MODE_WAKEUP FIELD_PREP(TMAG5273_OP_MODE_MASK, 3)
+
+/* bits in the TMAG5273_SENSOR_CONFIG_1 register */
+#define TMAG5273_MAG_CH_EN_MASK GENMASK(7, 4)
+#define TMAG5273_MAG_CH_EN_X_Y_Z 7
+
+/* bits in the TMAG5273_SENSOR_CONFIG_2 register */
+#define TMAG5273_Z_RANGE_MASK BIT(0)
+#define TMAG5273_X_Y_RANGE_MASK BIT(1)
+#define TMAG5273_ANGLE_EN_MASK GENMASK(3, 2)
+#define TMAG5273_ANGLE_EN_OFF 0
+#define TMAG5273_ANGLE_EN_X_Y 1
+#define TMAG5273_ANGLE_EN_Y_Z 2
+#define TMAG5273_ANGLE_EN_X_Z 3
+
+/* bits in the TMAG5273_T_CONFIG register */
+#define TMAG5273_T_CH_EN BIT(0)
+
+/* bits in the TMAG5273_DEVICE_ID register */
+#define TMAG5273_VERSION_MASK GENMASK(1, 0)
+
+/* bits in the TMAG5273_CONV_STATUS register */
+#define TMAG5273_CONV_STATUS_COMPLETE BIT(0)
+
+enum tmag5273_channels {
+ TEMPERATURE = 0,
+ AXIS_X,
+ AXIS_Y,
+ AXIS_Z,
+ ANGLE,
+ MAGNITUDE,
+};
+
+enum tmag5273_scale_index {
+ MAGN_RANGE_LOW = 0,
+ MAGN_RANGE_HIGH,
+ MAGN_RANGE_NUM
+};
+
+/* state container for the TMAG5273 driver */
+struct tmag5273_data {
+ struct device *dev;
+ unsigned int devid;
+ unsigned int version;
+ char name[16];
+ unsigned int conv_avg;
+ unsigned int scale;
+ enum tmag5273_scale_index scale_index;
+ unsigned int angle_measurement;
+ struct regmap *map;
+ struct regulator *vcc;
+
+ /*
+ * Locks the sensor for exclusive use during a measurement (which
+ * involves several register transactions so the regmap lock is not
+ * enough) so that measurements get serialized in a
+ * first-come-first-serve manner.
+ */
+ struct mutex lock;
+};
+
+static const char *const tmag5273_angle_names[] = { "off", "x-y", "y-z", "x-z" };
+
+/*
+ * Averaging enables additional sampling of the sensor data to reduce the noise
+ * effect, but also increases conversion time.
+ */
+static const unsigned int tmag5273_avg_table[] = {
+ 1, 2, 4, 8, 16, 32,
+};
+
+/*
+ * Magnetic resolution in Gauss for different TMAG5273 versions.
+ * Scale[Gauss] = Range[mT] * 1000 / 2^15 * 10, (1 mT = 10 Gauss)
+ * Only version 1 and 2 are valid, version 0 and 3 are reserved.
+ */
+static const struct iio_val_int_plus_micro tmag5273_scale[][MAGN_RANGE_NUM] = {
+ { { 0, 0 }, { 0, 0 } },
+ { { 0, 12200 }, { 0, 24400 } },
+ { { 0, 40600 }, { 0, 81200 } },
+ { { 0, 0 }, { 0, 0 } },
+};
+
+static int tmag5273_get_measure(struct tmag5273_data *data, s16 *t, s16 *x,
+ s16 *y, s16 *z, u16 *angle, u16 *magnitude)
+{
+ unsigned int status, val;
+ __be16 reg_data[4];
+ int ret;
+
+ mutex_lock(&data->lock);
+
+ /*
+ * Max. conversion time is 2425 us in 32x averaging mode for all three
+ * channels. Since we are in continuous measurement mode, a measurement
+ * may already be there, so poll for completed measurement with
+ * timeout.
+ */
+ ret = regmap_read_poll_timeout(data->map, TMAG5273_CONV_STATUS, status,
+ status & TMAG5273_CONV_STATUS_COMPLETE,
+ 100, 10000);
+ if (ret) {
+ dev_err_probe(data->dev, ret,
+ "timeout waiting for measurement\n");
+ goto out_unlock;
+ }
+
+ ret = regmap_bulk_read(data->map, TMAG5273_T_MSB_RESULT, reg_data,
+ sizeof(reg_data));
+ if (ret)
+ goto out_unlock;
+ *t = be16_to_cpu(reg_data[0]);
+ *x = be16_to_cpu(reg_data[1]);
+ *y = be16_to_cpu(reg_data[2]);
+ *z = be16_to_cpu(reg_data[3]);
+
+ ret = regmap_bulk_read(data->map, TMAG5273_ANGLE_RESULT_MSB,
+ &reg_data[0], sizeof(reg_data[0]));
+ if (ret)
+ goto out_unlock;
+ /*
+ * angle has 9 bits integer value and 4 bits fractional part
+ * 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
+ * 0 0 0 a a a a a a a a a f f f f
+ */
+ *angle = be16_to_cpu(reg_data[0]);
+
+ ret = regmap_read(data->map, TMAG5273_MAGNITUDE_RESULT, &val);
+ if (ret < 0)
+ goto out_unlock;
+ *magnitude = val;
+
+out_unlock:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static int tmag5273_write_osr(struct tmag5273_data *data, int val)
+{
+ int i;
+
+ if (val == data->conv_avg)
+ return 0;
+
+ for (i = 0; i < ARRAY_SIZE(tmag5273_avg_table); i++) {
+ if (tmag5273_avg_table[i] == val)
+ break;
+ }
+ if (i == ARRAY_SIZE(tmag5273_avg_table))
+ return -EINVAL;
+ data->conv_avg = val;
+
+ return regmap_update_bits(data->map, TMAG5273_DEVICE_CONFIG_1,
+ TMAG5273_AVG_MODE_MASK,
+ FIELD_PREP(TMAG5273_AVG_MODE_MASK, i));
+}
+
+static int tmag5273_write_scale(struct tmag5273_data *data, int scale_micro)
+{
+ u32 value;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(tmag5273_scale[0]); i++) {
+ if (tmag5273_scale[data->version][i].micro == scale_micro)
+ break;
+ }
+ if (i == ARRAY_SIZE(tmag5273_scale[0]))
+ return -EINVAL;
+ data->scale_index = i;
+
+ if (data->scale_index == MAGN_RANGE_LOW)
+ value = 0;
+ else
+ value = TMAG5273_Z_RANGE_MASK | TMAG5273_X_Y_RANGE_MASK;
+
+ return regmap_update_bits(data->map, TMAG5273_SENSOR_CONFIG_2,
+ TMAG5273_Z_RANGE_MASK | TMAG5273_X_Y_RANGE_MASK, value);
+}
+
+static int tmag5273_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long mask)
+{
+ struct tmag5273_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ *vals = tmag5273_avg_table;
+ *type = IIO_VAL_INT;
+ *length = ARRAY_SIZE(tmag5273_avg_table);
+ return IIO_AVAIL_LIST;
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_MAGN:
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ *vals = (int *)tmag5273_scale[data->version];
+ *length = ARRAY_SIZE(tmag5273_scale[data->version]) *
+ MAGN_RANGE_NUM;
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static int tmag5273_read_raw(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, int *val,
+ int *val2, long mask)
+{
+ struct tmag5273_data *data = iio_priv(indio_dev);
+ s16 t, x, y, z;
+ u16 angle, magnitude;
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_PROCESSED:
+ case IIO_CHAN_INFO_RAW:
+ ret = pm_runtime_resume_and_get(data->dev);
+ if (ret < 0)
+ return ret;
+
+ ret = tmag5273_get_measure(data, &t, &x, &y, &z, &angle, &magnitude);
+ if (ret)
+ return ret;
+
+ pm_runtime_mark_last_busy(data->dev);
+ pm_runtime_put_autosuspend(data->dev);
+
+ switch (chan->address) {
+ case TEMPERATURE:
+ *val = t;
+ return IIO_VAL_INT;
+ case AXIS_X:
+ *val = x;
+ return IIO_VAL_INT;
+ case AXIS_Y:
+ *val = y;
+ return IIO_VAL_INT;
+ case AXIS_Z:
+ *val = z;
+ return IIO_VAL_INT;
+ case ANGLE:
+ *val = angle;
+ return IIO_VAL_INT;
+ case MAGNITUDE:
+ *val = magnitude;
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_TEMP:
+ /*
+ * Convert device specific value to millicelsius.
+ * Resolution from the sensor is 60.1 LSB/celsius and
+ * the reference value at 25 celsius is 17508 LSBs.
+ */
+ *val = 10000;
+ *val2 = 601;
+ return IIO_VAL_FRACTIONAL;
+ case IIO_MAGN:
+ /* Magnetic resolution in uT */
+ *val = 0;
+ *val2 = tmag5273_scale[data->version]
+ [data->scale_index].micro;
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_ANGL:
+ /*
+ * Angle is in degrees and has four fractional bits,
+ * therefore use 1/16 * pi/180 to convert to radiants.
+ */
+ *val = 1000;
+ *val2 = 916732;
+ return IIO_VAL_FRACTIONAL;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_OFFSET:
+ switch (chan->type) {
+ case IIO_TEMP:
+ *val = -266314;
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ *val = data->conv_avg;
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int tmag5273_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val,
+ int val2, long mask)
+{
+ struct tmag5273_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ return tmag5273_write_osr(data, val);
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_MAGN:
+ if (val)
+ return -EINVAL;
+ return tmag5273_write_scale(data, val2);
+ default:
+ return -EINVAL;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+#define TMAG5273_AXIS_CHANNEL(axis, index) \
+ { \
+ .type = IIO_MAGN, \
+ .modified = 1, \
+ .channel2 = IIO_MOD_##axis, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_type_available = \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = \
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
+ .info_mask_shared_by_all_available = \
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
+ .address = index, \
+ .scan_index = index, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_CPU, \
+ }, \
+ }
+
+static const struct iio_chan_spec tmag5273_channels[] = {
+ {
+ .type = IIO_TEMP,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
+ .address = TEMPERATURE,
+ .scan_index = TEMPERATURE,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 16,
+ .storagebits = 16,
+ .endianness = IIO_CPU,
+ },
+ },
+ TMAG5273_AXIS_CHANNEL(X, AXIS_X),
+ TMAG5273_AXIS_CHANNEL(Y, AXIS_Y),
+ TMAG5273_AXIS_CHANNEL(Z, AXIS_Z),
+ {
+ .type = IIO_ANGL,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ .info_mask_shared_by_all =
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+ .info_mask_shared_by_all_available =
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+ .address = ANGLE,
+ .scan_index = ANGLE,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 16,
+ .storagebits = 16,
+ .endianness = IIO_CPU,
+ },
+ },
+ {
+ .type = IIO_DISTANCE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_all =
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+ .info_mask_shared_by_all_available =
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+ .address = MAGNITUDE,
+ .scan_index = MAGNITUDE,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 16,
+ .storagebits = 16,
+ .endianness = IIO_CPU,
+ },
+ },
+ IIO_CHAN_SOFT_TIMESTAMP(6),
+};
+
+static const struct iio_info tmag5273_info = {
+ .read_avail = &tmag5273_read_avail,
+ .read_raw = &tmag5273_read_raw,
+ .write_raw = &tmag5273_write_raw,
+};
+
+static bool tmag5273_volatile_reg(struct device *dev, unsigned int reg)
+{
+ return reg >= TMAG5273_T_MSB_RESULT && reg <= TMAG5273_MAGNITUDE_RESULT;
+}
+
+static const struct regmap_config tmag5273_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = TMAG5273_DEVICE_STATUS,
+ .volatile_reg = tmag5273_volatile_reg,
+};
+
+static int tmag5273_set_operating_mode(struct tmag5273_data *data,
+ unsigned int val)
+{
+ return regmap_write(data->map, TMAG5273_DEVICE_CONFIG_2, val);
+}
+
+static void tmag5273_read_device_property(struct tmag5273_data *data)
+{
+ struct device *dev = data->dev;
+ const char *str;
+ int ret;
+
+ data->angle_measurement = TMAG5273_ANGLE_EN_X_Y;
+
+ ret = device_property_read_string(dev, "ti,angle-measurement", &str);
+ if (ret)
+ return;
+
+ ret = match_string(tmag5273_angle_names,
+ ARRAY_SIZE(tmag5273_angle_names), str);
+ if (ret < 0)
+ dev_warn(dev, "unexpected read angle-measurement property: %s\n", str);
+ else
+ data->angle_measurement = ret;
+}
+
+static int tmag5273_chip_init(struct tmag5273_data *data)
+{
+ int ret;
+
+ ret = regmap_write(data->map, TMAG5273_DEVICE_CONFIG_1,
+ TMAG5273_AVG_32_MODE);
+ if (ret)
+ return ret;
+ data->conv_avg = 32;
+
+ ret = regmap_write(data->map, TMAG5273_DEVICE_CONFIG_2,
+ TMAG5273_OP_MODE_CONT);
+ if (ret)
+ return ret;
+
+ ret = regmap_write(data->map, TMAG5273_SENSOR_CONFIG_1,
+ FIELD_PREP(TMAG5273_MAG_CH_EN_MASK,
+ TMAG5273_MAG_CH_EN_X_Y_Z));
+ if (ret)
+ return ret;
+
+ ret = regmap_write(data->map, TMAG5273_SENSOR_CONFIG_2,
+ FIELD_PREP(TMAG5273_ANGLE_EN_MASK,
+ data->angle_measurement));
+ if (ret)
+ return ret;
+ data->scale_index = MAGN_RANGE_LOW;
+
+ return regmap_write(data->map, TMAG5273_T_CONFIG, TMAG5273_T_CH_EN);
+}
+
+static int tmag5273_wake_up_and_check_device_id(struct tmag5273_data *data)
+{
+ __le16 devid;
+ int val, ret;
+
+ /*
+ * If we come from sleep with power already activated, the
+ * first I2C command wakes up the chip but will fail.
+ * Time to go to stand-by mode from sleep mode is 50us
+ * typically. During this time no I2C access is possible.
+ */
+ regmap_read(data->map, TMAG5273_DEVICE_ID, &val);
+ usleep_range(80, 200);
+ ret = regmap_read(data->map, TMAG5273_DEVICE_ID, &val);
+ if (ret)
+ return dev_err_probe(data->dev, ret, "failed to power on device\n");
+ data->version = FIELD_PREP(TMAG5273_VERSION_MASK, val);
+
+ ret = regmap_bulk_read(data->map, TMAG5273_MANUFACTURER_ID_LSB, &devid,
+ sizeof(devid));
+ if (ret)
+ return dev_err_probe(data->dev, ret, "failed to read device ID\n");
+ data->devid = le16_to_cpu(devid);
+
+ switch (data->devid) {
+ case TMAG5273_MANUFACTURER_ID:
+ snprintf(data->name, sizeof(data->name), "tmag5273x%1u", data->version);
+ if (data->version < 1 || data->version > 2)
+ dev_warn(data->dev, "Unsupported device %s\n", data->name);
+ return 0;
+ default:
+ dev_warn(data->dev, "Unknown device ID 0x%x\n", data->devid);
+ return 0;
+ }
+}
+
+static void tmag5273_power_down(void *data)
+{
+ tmag5273_set_operating_mode(data, TMAG5273_OP_MODE_SLEEP);
+}
+
+static int tmag5273_probe(struct i2c_client *i2c)
+{
+ struct device *dev = &i2c->dev;
+ struct tmag5273_data *data;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ data = iio_priv(indio_dev);
+ data->dev = dev;
+ i2c_set_clientdata(i2c, indio_dev);
+
+ data->map = devm_regmap_init_i2c(i2c, &tmag5273_regmap_config);
+ if (IS_ERR(data->map))
+ return dev_err_probe(dev, PTR_ERR(data->map),
+ "failed to allocate register map\n");
+
+ mutex_init(&data->lock);
+
+ ret = devm_regulator_get_enable(dev, "vcc");
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to enable regulator\n");
+
+ ret = tmag5273_wake_up_and_check_device_id(data);
+ if (ret)
+ return ret;
+
+ ret = tmag5273_set_operating_mode(data, TMAG5273_OP_MODE_CONT);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to power on device\n");
+
+ /*
+ * Register powerdown deferred callback which suspends the chip
+ * after module unloaded.
+ *
+ * TMAG5273 should be in SUSPEND mode in the two cases:
+ * 1) When driver is loaded, but we do not have any data or
+ * configuration requests to it (we are solving it using
+ * autosuspend feature).
+ * 2) When driver is unloaded and device is not used (devm action is
+ * used in this case).
+ */
+ ret = devm_add_action_or_reset(dev, tmag5273_power_down, data);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to add powerdown action\n");
+
+ ret = pm_runtime_set_active(dev);
+ if (ret < 0)
+ return ret;
+
+ ret = devm_pm_runtime_enable(dev);
+ if (ret)
+ return ret;
+
+ pm_runtime_get_noresume(dev);
+ pm_runtime_set_autosuspend_delay(dev, TMAG5273_AUTOSLEEP_DELAY_MS);
+ pm_runtime_use_autosuspend(dev);
+
+ tmag5273_read_device_property(data);
+
+ ret = tmag5273_chip_init(data);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to init device\n");
+
+ indio_dev->info = &tmag5273_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->name = data->name;
+ indio_dev->channels = tmag5273_channels;
+ indio_dev->num_channels = ARRAY_SIZE(tmag5273_channels);
+
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ ret = devm_iio_device_register(dev, indio_dev);
+ if (ret)
+ return dev_err_probe(dev, ret, "device register failed\n");
+
+ return 0;
+}
+
+static int tmag5273_runtime_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct tmag5273_data *data = iio_priv(indio_dev);
+ int ret;
+
+ ret = tmag5273_set_operating_mode(data, TMAG5273_OP_MODE_SLEEP);
+ if (ret)
+ dev_err(dev, "failed to power off device (%pe)\n", ERR_PTR(ret));
+
+ return ret;
+}
+
+static int tmag5273_runtime_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct tmag5273_data *data = iio_priv(indio_dev);
+ int ret;
+
+ /*
+ * Time to go to stand-by mode from sleep mode is 50us
+ * typically. During this time no I2C access is possible.
+ */
+ tmag5273_set_operating_mode(data, TMAG5273_OP_MODE_CONT);
+ usleep_range(80, 200);
+ ret = tmag5273_set_operating_mode(data, TMAG5273_OP_MODE_CONT);
+ if (ret)
+ dev_err(dev, "failed to power on device (%pe)\n", ERR_PTR(ret));
+
+ return ret;
+}
+
+static DEFINE_RUNTIME_DEV_PM_OPS(tmag5273_pm_ops, tmag5273_runtime_suspend,
+ tmag5273_runtime_resume, NULL);
+
+static const struct i2c_device_id tmag5273_id[] = {
+ { "tmag5273" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, tmag5273_id);
+
+static const struct of_device_id tmag5273_of_match[] = {
+ { .compatible = "ti,tmag5273" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, tmag5273_of_match);
+
+static struct i2c_driver tmag5273_driver = {
+ .driver = {
+ .name = "tmag5273",
+ .of_match_table = tmag5273_of_match,
+ .pm = pm_ptr(&tmag5273_pm_ops),
+ },
+ .probe_new = tmag5273_probe,
+ .id_table = tmag5273_id,
+};
+module_i2c_driver(tmag5273_driver);
+
+MODULE_DESCRIPTION("TI TMAG5273 Low-Power Linear 3D Hall-Effect Sensor driver");
+MODULE_AUTHOR("Gerald Loacker <gerald.loacker@xxxxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
--
2.37.2