Re: [PATCH v1 4/7] iio: st_sensors: Call st_sensors_power_enable() from bus drivers

From: Jonathan Cameron
Date: Sun Apr 18 2021 - 06:53:44 EST


On Wed, 14 Apr 2021 22:54:51 +0300
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:

> In case we would initialize two IIO devices from one physical device,
> we shouldn't have a clash on regulators. That's why move
> st_sensors_power_enable() call from core to bus drivers.

Why is this a problem? The two instances would double up and both get +
enable + disable the regulators. However, that shouldn't matter as
they are reference counted anyway.

Perhaps an example? Even in patch 6 I can only see that it is wasteful
to do it twice, rather than wrong as such.

Jonathan


>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
> drivers/iio/accel/st_accel_core.c | 21 +++++----------------
> drivers/iio/accel/st_accel_i2c.c | 17 +++++++++++++++--
> drivers/iio/accel/st_accel_spi.c | 17 +++++++++++++++--
> drivers/iio/gyro/st_gyro_core.c | 15 +++------------
> drivers/iio/gyro/st_gyro_i2c.c | 17 +++++++++++++++--
> drivers/iio/gyro/st_gyro_spi.c | 17 +++++++++++++++--
> drivers/iio/magnetometer/st_magn_core.c | 15 +++------------
> drivers/iio/magnetometer/st_magn_i2c.c | 14 +++++++++++++-
> drivers/iio/magnetometer/st_magn_spi.c | 14 +++++++++++++-
> drivers/iio/pressure/st_pressure_core.c | 15 +++------------
> drivers/iio/pressure/st_pressure_i2c.c | 17 +++++++++++++++--
> drivers/iio/pressure/st_pressure_spi.c | 17 +++++++++++++++--
> 12 files changed, 130 insertions(+), 66 deletions(-)
>
> diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
> index a1bd7e3b912e..5c258c1ca62d 100644
> --- a/drivers/iio/accel/st_accel_core.c
> +++ b/drivers/iio/accel/st_accel_core.c
> @@ -1260,13 +1260,9 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
> indio_dev->modes = INDIO_DIRECT_MODE;
> indio_dev->info = &accel_info;
>
> - err = st_sensors_power_enable(indio_dev);
> - if (err)
> - return err;
> -
> err = st_sensors_verify_id(indio_dev);
> if (err < 0)
> - goto st_accel_power_off;
> + return err;
>
> adata->num_data_channels = ST_ACCEL_NUMBER_DATA_CHANNELS;
> indio_dev->num_channels = ST_SENSORS_NUMBER_ALL_CHANNELS;
> @@ -1275,10 +1271,8 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
> channels = devm_kmemdup(&indio_dev->dev,
> adata->sensor_settings->ch,
> channels_size, GFP_KERNEL);
> - if (!channels) {
> - err = -ENOMEM;
> - goto st_accel_power_off;
> - }
> + if (!channels)
> + return -ENOMEM;
>
> if (apply_acpi_orientation(indio_dev, channels))
> dev_warn(&indio_dev->dev,
> @@ -1293,11 +1287,11 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
>
> err = st_sensors_init_sensor(indio_dev, pdata);
> if (err < 0)
> - goto st_accel_power_off;
> + return err;
>
> err = st_accel_allocate_ring(indio_dev);
> if (err < 0)
> - goto st_accel_power_off;
> + return err;
>
> if (adata->irq > 0) {
> err = st_sensors_allocate_trigger(indio_dev,
> @@ -1320,9 +1314,6 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
> st_sensors_deallocate_trigger(indio_dev);
> st_accel_probe_trigger_error:
> st_accel_deallocate_ring(indio_dev);
> -st_accel_power_off:
> - st_sensors_power_disable(indio_dev);
> -
> return err;
> }
> EXPORT_SYMBOL(st_accel_common_probe);
> @@ -1331,8 +1322,6 @@ void st_accel_common_remove(struct iio_dev *indio_dev)
> {
> struct st_sensor_data *adata = iio_priv(indio_dev);
>
> - st_sensors_power_disable(indio_dev);
> -
> iio_device_unregister(indio_dev);
> if (adata->irq > 0)
> st_sensors_deallocate_trigger(indio_dev);
> diff --git a/drivers/iio/accel/st_accel_i2c.c b/drivers/iio/accel/st_accel_i2c.c
> index 360e16f2cadb..95e305b88d5e 100644
> --- a/drivers/iio/accel/st_accel_i2c.c
> +++ b/drivers/iio/accel/st_accel_i2c.c
> @@ -174,16 +174,29 @@ static int st_accel_i2c_probe(struct i2c_client *client)
> if (ret < 0)
> return ret;
>
> + ret = st_sensors_power_enable(indio_dev);
> + if (ret)
> + return ret;
> +
> ret = st_accel_common_probe(indio_dev);
> if (ret < 0)
> - return ret;
> + goto st_accel_power_off;
>
> return 0;
> +
> +st_accel_power_off:
> + st_sensors_power_disable(indio_dev);
> +
> + return ret;
> }
>
> static int st_accel_i2c_remove(struct i2c_client *client)
> {
> - st_accel_common_remove(i2c_get_clientdata(client));
> + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> + st_sensors_power_disable(indio_dev);
> +
> + st_accel_common_remove(indio_dev);
>
> return 0;
> }
> diff --git a/drivers/iio/accel/st_accel_spi.c b/drivers/iio/accel/st_accel_spi.c
> index 568ff1bae0ee..83d3308ce5cc 100644
> --- a/drivers/iio/accel/st_accel_spi.c
> +++ b/drivers/iio/accel/st_accel_spi.c
> @@ -123,16 +123,29 @@ static int st_accel_spi_probe(struct spi_device *spi)
> if (err < 0)
> return err;
>
> + err = st_sensors_power_enable(indio_dev);
> + if (err)
> + return err;
> +
> err = st_accel_common_probe(indio_dev);
> if (err < 0)
> - return err;
> + goto st_accel_power_off;
>
> return 0;
> +
> +st_accel_power_off:
> + st_sensors_power_disable(indio_dev);
> +
> + return err;
> }
>
> static int st_accel_spi_remove(struct spi_device *spi)
> {
> - st_accel_common_remove(spi_get_drvdata(spi));
> + struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +
> + st_sensors_power_disable(indio_dev);
> +
> + st_accel_common_remove(indio_dev);
>
> return 0;
> }
> diff --git a/drivers/iio/gyro/st_gyro_core.c b/drivers/iio/gyro/st_gyro_core.c
> index e000504e1df4..ee3f0ea96ac5 100644
> --- a/drivers/iio/gyro/st_gyro_core.c
> +++ b/drivers/iio/gyro/st_gyro_core.c
> @@ -471,13 +471,9 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
> indio_dev->modes = INDIO_DIRECT_MODE;
> indio_dev->info = &gyro_info;
>
> - err = st_sensors_power_enable(indio_dev);
> - if (err)
> - return err;
> -
> err = st_sensors_verify_id(indio_dev);
> if (err < 0)
> - goto st_gyro_power_off;
> + return err;
>
> gdata->num_data_channels = ST_GYRO_NUMBER_DATA_CHANNELS;
> indio_dev->channels = gdata->sensor_settings->ch;
> @@ -490,11 +486,11 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
>
> err = st_sensors_init_sensor(indio_dev, pdata);
> if (err < 0)
> - goto st_gyro_power_off;
> + return err;
>
> err = st_gyro_allocate_ring(indio_dev);
> if (err < 0)
> - goto st_gyro_power_off;
> + return err;
>
> if (gdata->irq > 0) {
> err = st_sensors_allocate_trigger(indio_dev,
> @@ -517,9 +513,6 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
> st_sensors_deallocate_trigger(indio_dev);
> st_gyro_probe_trigger_error:
> st_gyro_deallocate_ring(indio_dev);
> -st_gyro_power_off:
> - st_sensors_power_disable(indio_dev);
> -
> return err;
> }
> EXPORT_SYMBOL(st_gyro_common_probe);
> @@ -528,8 +521,6 @@ void st_gyro_common_remove(struct iio_dev *indio_dev)
> {
> struct st_sensor_data *gdata = iio_priv(indio_dev);
>
> - st_sensors_power_disable(indio_dev);
> -
> iio_device_unregister(indio_dev);
> if (gdata->irq > 0)
> st_sensors_deallocate_trigger(indio_dev);
> diff --git a/drivers/iio/gyro/st_gyro_i2c.c b/drivers/iio/gyro/st_gyro_i2c.c
> index 8190966e6ff0..a25cc0379e16 100644
> --- a/drivers/iio/gyro/st_gyro_i2c.c
> +++ b/drivers/iio/gyro/st_gyro_i2c.c
> @@ -86,16 +86,29 @@ static int st_gyro_i2c_probe(struct i2c_client *client,
> if (err < 0)
> return err;
>
> + err = st_sensors_power_enable(indio_dev);
> + if (err)
> + return err;
> +
> err = st_gyro_common_probe(indio_dev);
> if (err < 0)
> - return err;
> + goto st_gyro_power_off;
>
> return 0;
> +
> +st_gyro_power_off:
> + st_sensors_power_disable(indio_dev);
> +
> + return err;
> }
>
> static int st_gyro_i2c_remove(struct i2c_client *client)
> {
> - st_gyro_common_remove(i2c_get_clientdata(client));
> + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> + st_sensors_power_disable(indio_dev);
> +
> + st_gyro_common_remove(indio_dev);
>
> return 0;
> }
> diff --git a/drivers/iio/gyro/st_gyro_spi.c b/drivers/iio/gyro/st_gyro_spi.c
> index efb862763ca3..18d6a2aeda45 100644
> --- a/drivers/iio/gyro/st_gyro_spi.c
> +++ b/drivers/iio/gyro/st_gyro_spi.c
> @@ -90,16 +90,29 @@ static int st_gyro_spi_probe(struct spi_device *spi)
> if (err < 0)
> return err;
>
> + err = st_sensors_power_enable(indio_dev);
> + if (err)
> + return err;
> +
> err = st_gyro_common_probe(indio_dev);
> if (err < 0)
> - return err;
> + goto st_gyro_power_off;
>
> return 0;
> +
> +st_gyro_power_off:
> + st_sensors_power_disable(indio_dev);
> +
> + return err;
> }
>
> static int st_gyro_spi_remove(struct spi_device *spi)
> {
> - st_gyro_common_remove(spi_get_drvdata(spi));
> + struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +
> + st_sensors_power_disable(indio_dev);
> +
> + st_gyro_common_remove(indio_dev);
>
> return 0;
> }
> diff --git a/drivers/iio/magnetometer/st_magn_core.c b/drivers/iio/magnetometer/st_magn_core.c
> index cf3722e42419..018b2523edfe 100644
> --- a/drivers/iio/magnetometer/st_magn_core.c
> +++ b/drivers/iio/magnetometer/st_magn_core.c
> @@ -500,13 +500,9 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
> indio_dev->modes = INDIO_DIRECT_MODE;
> indio_dev->info = &magn_info;
>
> - err = st_sensors_power_enable(indio_dev);
> - if (err)
> - return err;
> -
> err = st_sensors_verify_id(indio_dev);
> if (err < 0)
> - goto st_magn_power_off;
> + return err;
>
> mdata->num_data_channels = ST_MAGN_NUMBER_DATA_CHANNELS;
> indio_dev->channels = mdata->sensor_settings->ch;
> @@ -520,11 +516,11 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
>
> err = st_sensors_init_sensor(indio_dev, pdata);
> if (err < 0)
> - goto st_magn_power_off;
> + return err;
>
> err = st_magn_allocate_ring(indio_dev);
> if (err < 0)
> - goto st_magn_power_off;
> + return err;
>
> if (mdata->irq > 0) {
> err = st_sensors_allocate_trigger(indio_dev,
> @@ -547,9 +543,6 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
> st_sensors_deallocate_trigger(indio_dev);
> st_magn_probe_trigger_error:
> st_magn_deallocate_ring(indio_dev);
> -st_magn_power_off:
> - st_sensors_power_disable(indio_dev);
> -
> return err;
> }
> EXPORT_SYMBOL(st_magn_common_probe);
> @@ -558,8 +551,6 @@ void st_magn_common_remove(struct iio_dev *indio_dev)
> {
> struct st_sensor_data *mdata = iio_priv(indio_dev);
>
> - st_sensors_power_disable(indio_dev);
> -
> iio_device_unregister(indio_dev);
> if (mdata->irq > 0)
> st_sensors_deallocate_trigger(indio_dev);
> diff --git a/drivers/iio/magnetometer/st_magn_i2c.c b/drivers/iio/magnetometer/st_magn_i2c.c
> index c6bb4ce77594..7a7ab27379fc 100644
> --- a/drivers/iio/magnetometer/st_magn_i2c.c
> +++ b/drivers/iio/magnetometer/st_magn_i2c.c
> @@ -78,16 +78,28 @@ static int st_magn_i2c_probe(struct i2c_client *client,
> if (err < 0)
> return err;
>
> + err = st_sensors_power_enable(indio_dev);
> + if (err)
> + return err;
> +
> err = st_magn_common_probe(indio_dev);
> if (err < 0)
> - return err;
> + goto st_magn_power_off;
>
> return 0;
> +
> +st_magn_power_off:
> + st_sensors_power_disable(indio_dev);
> +
> + return err;
> }
>
> static int st_magn_i2c_remove(struct i2c_client *client)
> {
> struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> + st_sensors_power_disable(indio_dev);
> +
> st_magn_common_remove(indio_dev);
>
> return 0;
> diff --git a/drivers/iio/magnetometer/st_magn_spi.c b/drivers/iio/magnetometer/st_magn_spi.c
> index 3d08d74c367d..ee352f083c02 100644
> --- a/drivers/iio/magnetometer/st_magn_spi.c
> +++ b/drivers/iio/magnetometer/st_magn_spi.c
> @@ -72,16 +72,28 @@ static int st_magn_spi_probe(struct spi_device *spi)
> if (err < 0)
> return err;
>
> + err = st_sensors_power_enable(indio_dev);
> + if (err)
> + return err;
> +
> err = st_magn_common_probe(indio_dev);
> if (err < 0)
> - return err;
> + goto st_magn_power_off;
>
> return 0;
> +
> +st_magn_power_off:
> + st_sensors_power_disable(indio_dev);
> +
> + return err;
> }
>
> static int st_magn_spi_remove(struct spi_device *spi)
> {
> struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +
> + st_sensors_power_disable(indio_dev);
> +
> st_magn_common_remove(indio_dev);
>
> return 0;
> diff --git a/drivers/iio/pressure/st_pressure_core.c b/drivers/iio/pressure/st_pressure_core.c
> index 789a2928504a..7912b5a68395 100644
> --- a/drivers/iio/pressure/st_pressure_core.c
> +++ b/drivers/iio/pressure/st_pressure_core.c
> @@ -689,13 +689,9 @@ int st_press_common_probe(struct iio_dev *indio_dev)
> indio_dev->modes = INDIO_DIRECT_MODE;
> indio_dev->info = &press_info;
>
> - err = st_sensors_power_enable(indio_dev);
> - if (err)
> - return err;
> -
> err = st_sensors_verify_id(indio_dev);
> if (err < 0)
> - goto st_press_power_off;
> + return err;
>
> /*
> * Skip timestamping channel while declaring available channels to
> @@ -718,11 +714,11 @@ int st_press_common_probe(struct iio_dev *indio_dev)
>
> err = st_sensors_init_sensor(indio_dev, pdata);
> if (err < 0)
> - goto st_press_power_off;
> + return err;
>
> err = st_press_allocate_ring(indio_dev);
> if (err < 0)
> - goto st_press_power_off;
> + return err;
>
> if (press_data->irq > 0) {
> err = st_sensors_allocate_trigger(indio_dev,
> @@ -745,9 +741,6 @@ int st_press_common_probe(struct iio_dev *indio_dev)
> st_sensors_deallocate_trigger(indio_dev);
> st_press_probe_trigger_error:
> st_press_deallocate_ring(indio_dev);
> -st_press_power_off:
> - st_sensors_power_disable(indio_dev);
> -
> return err;
> }
> EXPORT_SYMBOL(st_press_common_probe);
> @@ -756,8 +749,6 @@ void st_press_common_remove(struct iio_dev *indio_dev)
> {
> struct st_sensor_data *press_data = iio_priv(indio_dev);
>
> - st_sensors_power_disable(indio_dev);
> -
> iio_device_unregister(indio_dev);
> if (press_data->irq > 0)
> st_sensors_deallocate_trigger(indio_dev);
> diff --git a/drivers/iio/pressure/st_pressure_i2c.c b/drivers/iio/pressure/st_pressure_i2c.c
> index 09c6903f99b8..f0a5af314ceb 100644
> --- a/drivers/iio/pressure/st_pressure_i2c.c
> +++ b/drivers/iio/pressure/st_pressure_i2c.c
> @@ -98,16 +98,29 @@ static int st_press_i2c_probe(struct i2c_client *client,
> if (ret < 0)
> return ret;
>
> + ret = st_sensors_power_enable(indio_dev);
> + if (ret)
> + return ret;
> +
> ret = st_press_common_probe(indio_dev);
> if (ret < 0)
> - return ret;
> + goto st_press_power_off;
>
> return 0;
> +
> +st_press_power_off:
> + st_sensors_power_disable(indio_dev);
> +
> + return ret;
> }
>
> static int st_press_i2c_remove(struct i2c_client *client)
> {
> - st_press_common_remove(i2c_get_clientdata(client));
> + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> + st_sensors_power_disable(indio_dev);
> +
> + st_press_common_remove(indio_dev);
>
> return 0;
> }
> diff --git a/drivers/iio/pressure/st_pressure_spi.c b/drivers/iio/pressure/st_pressure_spi.c
> index b5ee3ec2764f..b48cf7d01cd7 100644
> --- a/drivers/iio/pressure/st_pressure_spi.c
> +++ b/drivers/iio/pressure/st_pressure_spi.c
> @@ -82,16 +82,29 @@ static int st_press_spi_probe(struct spi_device *spi)
> if (err < 0)
> return err;
>
> + err = st_sensors_power_enable(indio_dev);
> + if (err)
> + return err;
> +
> err = st_press_common_probe(indio_dev);
> if (err < 0)
> - return err;
> + goto st_press_power_off;
>
> return 0;
> +
> +st_press_power_off:
> + st_sensors_power_disable(indio_dev);
> +
> + return err;
> }
>
> static int st_press_spi_remove(struct spi_device *spi)
> {
> - st_press_common_remove(spi_get_drvdata(spi));
> + struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +
> + st_sensors_power_disable(indio_dev);
> +
> + st_press_common_remove(indio_dev);
>
> return 0;
> }