iio: imu: inv_icm42600: add temperature sensor support

Add temperature channel in gyroscope and accelerometer devices.

Temperature is available in full 16 bits resolution when reading
register and in low 8 bits resolution in the FIFO. Return full
precision raw temperature with corresponding scale and offset.

Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
index 717c6b0..3f214df 100644 (file)
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
@@ -13,6 +13,7 @@
 #include <linux/iio/iio.h>
 
 #include "inv_icm42600.h"
+#include "inv_icm42600_temp.h"
 
 #define INV_ICM42600_ACCEL_CHAN(_modifier, _index, _ext_info)          \
        {                                                               \
@@ -45,6 +46,7 @@ enum inv_icm42600_accel_scan {
        INV_ICM42600_ACCEL_SCAN_X,
        INV_ICM42600_ACCEL_SCAN_Y,
        INV_ICM42600_ACCEL_SCAN_Z,
+       INV_ICM42600_ACCEL_SCAN_TEMP,
 };
 
 static const struct iio_chan_spec_ext_info inv_icm42600_accel_ext_infos[] = {
@@ -59,6 +61,7 @@ static const struct iio_chan_spec inv_icm42600_accel_channels[] = {
                                inv_icm42600_accel_ext_infos),
        INV_ICM42600_ACCEL_CHAN(IIO_MOD_Z, INV_ICM42600_ACCEL_SCAN_Z,
                                inv_icm42600_accel_ext_infos),
+       INV_ICM42600_TEMP_CHAN(INV_ICM42600_ACCEL_SCAN_TEMP),
 };
 
 static int inv_icm42600_accel_read_sensor(struct inv_icm42600_state *st,
@@ -450,8 +453,14 @@ static int inv_icm42600_accel_read_raw(struct iio_dev *indio_dev,
        int16_t data;
        int ret;
 
-       if (chan->type != IIO_ACCEL)
+       switch (chan->type) {
+       case IIO_ACCEL:
+               break;
+       case IIO_TEMP:
+               return inv_icm42600_temp_read_raw(indio_dev, chan, val, val2, mask);
+       default:
                return -EINVAL;
+       }
 
        switch (mask) {
        case IIO_CHAN_INFO_RAW:

diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_gyro.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_gyro.c
index 3875ecb..6a0e766 100644 (file)
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_gyro.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_gyro.c
@@ -13,6 +13,7 @@
 #include <linux/iio/iio.h>
 
 #include "inv_icm42600.h"
+#include "inv_icm42600_temp.h"
 
 #define INV_ICM42600_GYRO_CHAN(_modifier, _index, _ext_info)           \
        {                                                               \
@@ -45,6 +46,7 @@ enum inv_icm42600_gyro_scan {
        INV_ICM42600_GYRO_SCAN_X,
        INV_ICM42600_GYRO_SCAN_Y,
        INV_ICM42600_GYRO_SCAN_Z,
+       INV_ICM42600_GYRO_SCAN_TEMP,
 };
 
 static const struct iio_chan_spec_ext_info inv_icm42600_gyro_ext_infos[] = {
@@ -59,6 +61,7 @@ static const struct iio_chan_spec inv_icm42600_gyro_channels[] = {
                               inv_icm42600_gyro_ext_infos),
        INV_ICM42600_GYRO_CHAN(IIO_MOD_Z, INV_ICM42600_GYRO_SCAN_Z,
                               inv_icm42600_gyro_ext_infos),
+       INV_ICM42600_TEMP_CHAN(INV_ICM42600_GYRO_SCAN_TEMP),
 };
 
 static int inv_icm42600_gyro_read_sensor(struct inv_icm42600_state *st,
@@ -461,8 +464,14 @@ static int inv_icm42600_gyro_read_raw(struct iio_dev *indio_dev,
        int16_t data;
        int ret;
 
-       if (chan->type != IIO_ANGL_VEL)
+       switch (chan->type) {
+       case IIO_ANGL_VEL:
+               break;
+       case IIO_TEMP:
+               return inv_icm42600_temp_read_raw(indio_dev, chan, val, val2, mask);
+       default:
                return -EINVAL;
+       }
 
        switch (mask) {
        case IIO_CHAN_INFO_RAW:

diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_temp.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_temp.c
new file mode 100644 (file)
index 0000000..213cce1
--- /dev/null
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_temp.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2020 Invensense, Inc.
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+
+#include "inv_icm42600.h"
+#include "inv_icm42600_temp.h"
+
+static int inv_icm42600_temp_read(struct inv_icm42600_state *st, int16_t *temp)
+{
+       struct device *dev = regmap_get_device(st->map);
+       __be16 *raw;
+       int ret;
+
+       pm_runtime_get_sync(dev);
+       mutex_lock(&st->lock);
+
+       ret = inv_icm42600_set_temp_conf(st, true, NULL);
+       if (ret)
+               goto exit;
+
+       raw = (__be16 *)&st->buffer[0];
+       ret = regmap_bulk_read(st->map, INV_ICM42600_REG_TEMP_DATA, raw, sizeof(*raw));
+       if (ret)
+               goto exit;
+
+       *temp = (int16_t)be16_to_cpup(raw);
+       if (*temp == INV_ICM42600_DATA_INVALID)
+               ret = -EINVAL;
+
+exit:
+       mutex_unlock(&st->lock);
+       pm_runtime_mark_last_busy(dev);
+       pm_runtime_put_autosuspend(dev);
+
+       return ret;
+}
+
+int inv_icm42600_temp_read_raw(struct iio_dev *indio_dev,
+                              struct iio_chan_spec const *chan,
+                              int *val, int *val2, long mask)
+{
+       struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
+       int16_t temp;
+       int ret;
+
+       if (chan->type != IIO_TEMP)
+               return -EINVAL;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+               ret = iio_device_claim_direct_mode(indio_dev);
+               if (ret)
+                       return ret;
+               ret = inv_icm42600_temp_read(st, &temp);
+               iio_device_release_direct_mode(indio_dev);
+               if (ret)
+                       return ret;
+               *val = temp;
+               return IIO_VAL_INT;
+       /*
+        * T°C = (temp / 132.48) + 25
+        * Tm°C = 1000 * ((temp * 100 / 13248) + 25)
+        * scale: 100000 / 13248 ~= 7.548309
+        * offset: 25000
+        */
+       case IIO_CHAN_INFO_SCALE:
+               *val = 7;
+               *val2 = 548309;
+               return IIO_VAL_INT_PLUS_MICRO;
+       case IIO_CHAN_INFO_OFFSET:
+               *val = 25000;
+               return IIO_VAL_INT;
+       default:
+               return -EINVAL;
+       }
+}

diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_temp.h b/drivers/iio/imu/inv_icm42600/inv_icm42600_temp.h
new file mode 100644 (file)
index 0000000..3941186
--- /dev/null
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_temp.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2020 Invensense, Inc.
+ */
+
+#ifndef INV_ICM42600_TEMP_H_
+#define INV_ICM42600_TEMP_H_
+
+#include <linux/iio/iio.h>
+
+#define INV_ICM42600_TEMP_CHAN(_index)                                 \
+       {                                                               \
+               .type = IIO_TEMP,                                       \
+               .info_mask_separate =                                   \
+                       BIT(IIO_CHAN_INFO_RAW) |                        \
+                       BIT(IIO_CHAN_INFO_OFFSET) |                     \
+                       BIT(IIO_CHAN_INFO_SCALE),                       \
+               .scan_index = _index,                                   \
+               .scan_type = {                                          \
+                       .sign = 's',                                    \
+                       .realbits = 16,                                 \
+                       .storagebits = 16,                              \
+               },                                                      \
+       }
+
+int inv_icm42600_temp_read_raw(struct iio_dev *indio_dev,
+                              struct iio_chan_spec const *chan,
+                              int *val, int *val2, long mask);
+
+#endif