[PATCH V17 8/9] iio: imu: inv_icm42607: Add Temp Support in icm42607
Jonathan Cameron
jonathan.cameron at oss.qualcomm.com
Sat Jul 18 15:59:34 PDT 2026
On Thu, 16 Jul 2026 13:26:35 -0500
Chris Morgan <macroalpha82 at gmail.com> wrote:
> From: Chris Morgan <macromorgan at hotmail.com>
>
> Add functions for reading temperature sensor data.
Hi Chris
Before I take a look myself. Sashiko did have a comment on this
one that looks valid to me
https://sashiko.dev/#/patchset/20260716182637.24310-1-macroalpha82%40gmail.com
See comments on the the IIO_TEMP vs IIO_CHAN_INFO_RAW below.
The suspend one is interesting but definitely not something I'd insist
on fixing. Might need some thought if you actually want suspend to work
in all cases.
Jonathan
>
> Signed-off-by: Chris Morgan <macromorgan at hotmail.com>
> ---
> drivers/iio/imu/inv_icm42607/Makefile | 1 +
> .../iio/imu/inv_icm42607/inv_icm42607_accel.c | 6 ++
> .../iio/imu/inv_icm42607/inv_icm42607_gyro.c | 6 ++
> .../iio/imu/inv_icm42607/inv_icm42607_temp.c | 98 +++++++++++++++++++
> .../iio/imu/inv_icm42607/inv_icm42607_temp.h | 38 +++++++
> 5 files changed, 149 insertions(+)
> create mode 100644 drivers/iio/imu/inv_icm42607/inv_icm42607_temp.c
> create mode 100644 drivers/iio/imu/inv_icm42607/inv_icm42607_temp.h
>
> diff --git a/drivers/iio/imu/inv_icm42607/Makefile b/drivers/iio/imu/inv_icm42607/Makefile
> index 8e73385c8f4b..7b907e019601 100644
> --- a/drivers/iio/imu/inv_icm42607/Makefile
> +++ b/drivers/iio/imu/inv_icm42607/Makefile
> @@ -4,6 +4,7 @@ obj-$(CONFIG_INV_ICM42607) += inv-icm42607.o
> inv-icm42607-y += inv_icm42607_core.o
> inv-icm42607-y += inv_icm42607_gyro.o
> inv-icm42607-y += inv_icm42607_accel.o
> +inv-icm42607-y += inv_icm42607_temp.o
>
> obj-$(CONFIG_INV_ICM42607_I2C) += inv-icm42607-i2c.o
> inv-icm42607-i2c-y += inv_icm42607_i2c.o
> diff --git a/drivers/iio/imu/inv_icm42607/inv_icm42607_accel.c b/drivers/iio/imu/inv_icm42607/inv_icm42607_accel.c
> index 7bb67f232d19..9a44a180e5cc 100644
> --- a/drivers/iio/imu/inv_icm42607/inv_icm42607_accel.c
> +++ b/drivers/iio/imu/inv_icm42607/inv_icm42607_accel.c
> @@ -15,6 +15,7 @@
> #include <linux/types.h>
>
> #include "inv_icm42607.h"
> +#include "inv_icm42607_temp.h"
>
> #define INV_ICM42607_ACCEL_CHAN(_modifier, _index, _ext_info) \
> { \
> @@ -40,6 +41,7 @@ enum inv_icm42607_accel_scan {
> INV_ICM42607_ACCEL_SCAN_X,
> INV_ICM42607_ACCEL_SCAN_Y,
> INV_ICM42607_ACCEL_SCAN_Z,
> + INV_ICM42607_ACCEL_SCAN_TEMP,
> };
>
> static const struct iio_chan_spec_ext_info inv_icm42607_accel_ext_infos[] = {
> @@ -54,6 +56,7 @@ static const struct iio_chan_spec inv_icm42607_accel_channels[] = {
> inv_icm42607_accel_ext_infos),
> INV_ICM42607_ACCEL_CHAN(IIO_MOD_Z, INV_ICM42607_ACCEL_SCAN_Z,
> inv_icm42607_accel_ext_infos),
> + INV_ICM42607_TEMP_CHAN(INV_ICM42607_ACCEL_SCAN_TEMP),
> };
>
> static const int inv_icm42607_accel_scale_nano[][2] = {
> @@ -186,6 +189,9 @@ static int inv_icm42607_accel_read_raw(struct iio_dev *indio_dev,
>
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> + if (chan->type == IIO_TEMP)
> + return inv_icm42607_temp_read_raw(indio_dev, chan,
So this only gets called if mask is IIO_CHAN_INFO_RAW but look at what is implemented...
Sashiko suggeted this should be outside the switch and that looks correct
to me as well.
> + val, val2, mask);
> ret = inv_icm42607_read_sensor(indio_dev, chan, &data);
> if (ret)
> return ret;
> diff --git a/drivers/iio/imu/inv_icm42607/inv_icm42607_gyro.c b/drivers/iio/imu/inv_icm42607/inv_icm42607_gyro.c
> index 923d47d096bd..fa6e65c7ab6b 100644
> --- a/drivers/iio/imu/inv_icm42607/inv_icm42607_gyro.c
> +++ b/drivers/iio/imu/inv_icm42607/inv_icm42607_gyro.c
> @@ -15,6 +15,7 @@
> #include <linux/types.h>
>
> #include "inv_icm42607.h"
> +#include "inv_icm42607_temp.h"
>
> #define INV_ICM42607_GYRO_CHAN(_modifier, _index, _ext_info) \
> { \
> @@ -40,6 +41,7 @@ enum inv_icm42607_gyro_scan {
> INV_ICM42607_GYRO_SCAN_X,
> INV_ICM42607_GYRO_SCAN_Y,
> INV_ICM42607_GYRO_SCAN_Z,
> + INV_ICM42607_GYRO_SCAN_TEMP,
> };
>
> static const struct iio_chan_spec_ext_info inv_icm42607_gyro_ext_infos[] = {
> @@ -54,6 +56,7 @@ static const struct iio_chan_spec inv_icm42607_gyro_channels[] = {
> inv_icm42607_gyro_ext_infos),
> INV_ICM42607_GYRO_CHAN(IIO_MOD_Z, INV_ICM42607_GYRO_SCAN_Z,
> inv_icm42607_gyro_ext_infos),
> + INV_ICM42607_TEMP_CHAN(INV_ICM42607_GYRO_SCAN_TEMP),
> };
>
> static const int inv_icm42607_gyro_scale_nano[][2] = {
> @@ -183,6 +186,9 @@ static int inv_icm42607_gyro_read_raw(struct iio_dev *indio_dev,
>
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> + if (chan->type == IIO_TEMP)
> + return inv_icm42607_temp_read_raw(indio_dev, chan,
> + val, val2, mask);
> ret = inv_icm42607_read_sensor(indio_dev, chan, &data);
> if (ret)
> return ret;
> diff --git a/drivers/iio/imu/inv_icm42607/inv_icm42607_temp.c b/drivers/iio/imu/inv_icm42607/inv_icm42607_temp.c
> new file mode 100644
> index 000000000000..8681ef2b49e2
> --- /dev/null
> +++ b/drivers/iio/imu/inv_icm42607/inv_icm42607_temp.c
> @@ -0,0 +1,98 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2026 InvenSense, Inc.
> + */
> +
> +#include <linux/cleanup.h>
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/iio/iio.h>
> +#include <linux/mutex.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regmap.h>
> +#include <linux/types.h>
> +#include <linux/unaligned.h>
> +
> +#include "inv_icm42607.h"
> +#include "inv_icm42607_temp.h"
> +
> +static int inv_icm42607_temp_read(struct inv_icm42607_state *st, s16 *temp)
> +{
> + struct inv_icm42607_sensor_conf conf = INV_ICM42607_SENSOR_CONF_INIT;
> + struct device *dev = regmap_get_device(st->map);
> + int ret, gyro_mode, accel_mode;
> + unsigned int val;
> + u8 raw[2];
> +
> + PM_RUNTIME_ACQUIRE_AUTOSUSPEND(dev, pm);
> + ret = PM_RUNTIME_ACQUIRE_ERR(&pm);
> + if (ret)
> + return ret;
> +
> + guard(mutex)(&st->lock);
> +
> + /*
> + * Check if both the gyro and accel are off and if so, enable one
> + * of them. The temp sensor cannot be read if both the gyro and
> + * accel sensor are off. Prefer to enable the accel over the gyro
> + * as the datasheet says the gyro uses 5x more power and it has
> + * a minimum run time of 45ms.
> + */
> + ret = regmap_read(st->map, INV_ICM42607_REG_PWR_MGMT0, &val);
> + if (ret)
> + return ret;
> +
> + accel_mode = FIELD_GET(INV_ICM42607_PWR_MGMT0_ACCEL_MODE_MASK, val);
> + gyro_mode = FIELD_GET(INV_ICM42607_PWR_MGMT0_GYRO_MODE_MASK, val);
> + if (!gyro_mode && !accel_mode) {
> + /* enable accel sensor */
> + conf.mode = INV_ICM42607_SENSOR_MODE_LOW_NOISE;
> + ret = inv_icm42607_set_sensor_conf(st, &conf, IIO_ACCEL);
> + if (ret)
> + return ret;
> + }
> +
> + ret = regmap_bulk_read(st->map, INV_ICM42607_REG_TEMP_DATA1,
> + raw, sizeof(raw));
> + if (ret)
> + return ret;
> +
> + *temp = get_unaligned_be16(raw);
> + if (*temp == INV_ICM42607_DATA_INVALID)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +int inv_icm42607_temp_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct inv_icm42607_state *st = iio_device_get_drvdata(indio_dev);
> + s16 temp;
> + int ret;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
Only this case is ever called. (Sashiko pointed this out).
> + ret = inv_icm42607_temp_read(st, &temp);
> + if (ret)
> + return ret;
> + *val = temp;
> + return IIO_VAL_INT;
> + /*
> + * T°C = (temp / 128) + 25
> + * Tm°C = 1000 * ((temp * 100 / 12800) + 25)
> + * scale: 100000 / 12800 ~= 7.8125
> + * offset: 3200
> + */
> + case IIO_CHAN_INFO_SCALE:
> + *val = 7;
> + *val2 = 812500000;
> + return IIO_VAL_INT_PLUS_NANO;
> + case IIO_CHAN_INFO_OFFSET:
> + *val = 3200;
> + return IIO_VAL_INT;
> + default:
> + return -EINVAL;
> + }
> +}
> diff --git a/drivers/iio/imu/inv_icm42607/inv_icm42607_temp.h b/drivers/iio/imu/inv_icm42607/inv_icm42607_temp.h
> new file mode 100644
> index 000000000000..18499b4d0b94
> --- /dev/null
> +++ b/drivers/iio/imu/inv_icm42607/inv_icm42607_temp.h
> @@ -0,0 +1,38 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Copyright (C) 2026 InvenSense, Inc.
> + */
> +
> +#ifndef INV_ICM42607_TEMP_H_
> +#define INV_ICM42607_TEMP_H_
> +
> +#include <linux/bitops.h>
> +
> +struct iio_dev;
> +struct iio_chan_spec;
> +
> +#define INV_ICM42607_TEMP_CHAN(_index) \
> +{ \
> + .type = IIO_TEMP, \
> + .info_mask_separate = \
> + BIT(IIO_CHAN_INFO_RAW) | \
> + BIT(IIO_CHAN_INFO_OFFSET) | \
> + BIT(IIO_CHAN_INFO_SCALE), \
> + .info_mask_shared_by_all = \
> + BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> + .info_mask_shared_by_all_available = \
> + BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> + .scan_index = _index, \
> + .scan_type = { \
> + .sign = 's', \
> + .realbits = 16, \
> + .storagebits = 16, \
> + .endianness = IIO_BE, \
> + }, \
> +}
> +
> +int inv_icm42607_temp_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask);
> +
> +#endif
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