[PATCH v3 06/13] iio: imu: inv_icm42600: add temperature sensor support

Jean-Baptiste Maneyrol
2020-06-08T20:44:11Z

Add temperature channel in gyroscope and accelerometer devices.

Temperature is available in full 16 bits resolution as a processed
channel. Scale and offset attributes are also provided for the low
8 bits resolution raw temperature found in the FIFO.

Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
---
.../iio/imu/inv_icm42600/inv_icm42600_accel.c | 11 ++-
.../iio/imu/inv_icm42600/inv_icm42600_gyro.c | 11 ++-
.../iio/imu/inv_icm42600/inv_icm42600_temp.c | 87 +++++++++++++++++++
.../iio/imu/inv_icm42600/inv_icm42600_temp.h | 30 +++++++
4 files changed, 137 insertions(+), 2 deletions(-)
create mode 100644 drivers/iio/imu/inv_icm42600/inv_icm42600_temp.c
create mode 100644 drivers/iio/imu/inv_icm42600/inv_icm42600_temp.h

diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
index 717c6b0869fc..3f214df44093 100644
--- 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 3875ecbee67e..6a0e7661fa48 100644
--- 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
index 000000000000..b0871352fe39
--- /dev/null
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_temp.c
@@ -0,0 +1,87 @@
+// 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/math64.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, int32_t *temp)
+{
+ struct device *dev = regmap_get_device(st->map);
+ int64_t data;
+ __be16 *raw;
+ int16_t val;
+ 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;
+
+ val = (int16_t)be16_to_cpup(raw);
+ if (val == INV_ICM42600_DATA_INVALID) {
+ ret = -EINVAL;
+ goto exit;
+ }
+ /*
+ * T°C = (val / 132.48) + 25 = ((val * 100) / 13248) + 25
+ * Tm°C = (val * 100 * 1000) / 13248 + 25000
+ */
+ data = (int64_t)(val) * 100LL * 1000LL;
+ *temp = div_s64(data, 13248) + 25000;
+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);
+ int32_t temp;
+ int ret;
+
+ if (chan->type != IIO_TEMP)
+ return -EINVAL;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_PROCESSED:
+ 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;
+ case IIO_CHAN_INFO_SCALE:
+ *val = 483;
+ *val2 = 91787;
+ 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
index 000000000000..2c3a932faa94
--- /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_PROCESSED) | \
+ BIT(IIO_CHAN_INFO_OFFSET) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .scan_index = _index, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 8, \
+ .storagebits = 8, \
+ }, \
+ }
+
+int inv_icm42600_temp_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask);
+
+#endif
--
2.17.1