Re: [PATCH] iio: imu: st_lsm6dsx: use i2c/spi device name for iio_dev name

[Jonathan Cameron <jic23@kernel.org>]

On 03/04/17 18:27, Lorenzo Bianconi wrote:
> Use the correct chip name (e.g. lsm6dsm) as suffix for iio_dev name
> instead of a generic one (lsm6dsx)
> 
> Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Hmm. Always a fun one.  Technically this is changing a userspace
ABI so is a problem unless we think no one will notice...

The question is whether the gain is worth the potential risk?

What do people think?

J
> ---
>  drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h      |  4 +++-
>  drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 14 +++++++++-----
>  drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c  |  2 +-
>  drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c  |  2 +-
>  4 files changed, 14 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
> index 6a9849e..4839db7 100644
> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
> @@ -71,6 +71,7 @@ enum st_lsm6dsx_fifo_mode {
>  
>  /**
>   * struct st_lsm6dsx_sensor - ST IMU sensor instance
> + * @name: Sensor name.
>   * @id: Sensor identifier.
>   * @hw: Pointer to instance of struct st_lsm6dsx_hw.
>   * @gain: Configured sensor sensitivity.
> @@ -83,6 +84,7 @@ enum st_lsm6dsx_fifo_mode {
>   * @ts: Latest timestamp from the interrupt handler.
>   */
>  struct st_lsm6dsx_sensor {
> +	char name[32];
>  	enum st_lsm6dsx_sensor_id id;
>  	struct st_lsm6dsx_hw *hw;
>  
> @@ -133,7 +135,7 @@ struct st_lsm6dsx_hw {
>  #endif /* CONFIG_SPI_MASTER */
>  };
>  
> -int st_lsm6dsx_probe(struct device *dev, int irq, int hw_id,
> +int st_lsm6dsx_probe(struct device *dev, int irq, int hw_id, const char *name,
>  		     const struct st_lsm6dsx_transfer_function *tf_ops);
>  int st_lsm6dsx_sensor_enable(struct st_lsm6dsx_sensor *sensor);
>  int st_lsm6dsx_sensor_disable(struct st_lsm6dsx_sensor *sensor);
> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
> index f80a3d4..98b51d7 100644
> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
> @@ -642,7 +642,8 @@ static int st_lsm6dsx_init_device(struct st_lsm6dsx_hw *hw)
>  }
>  
>  static struct iio_dev *st_lsm6dsx_alloc_iiodev(struct st_lsm6dsx_hw *hw,
> -					       enum st_lsm6dsx_sensor_id id)
> +					       enum st_lsm6dsx_sensor_id id,
> +					       const char *name)
>  {
>  	struct st_lsm6dsx_sensor *sensor;
>  	struct iio_dev *iio_dev;
> @@ -666,27 +667,30 @@ static struct iio_dev *st_lsm6dsx_alloc_iiodev(struct st_lsm6dsx_hw *hw,
>  	case ST_LSM6DSX_ID_ACC:
>  		iio_dev->channels = st_lsm6dsx_acc_channels;
>  		iio_dev->num_channels = ARRAY_SIZE(st_lsm6dsx_acc_channels);
> -		iio_dev->name = "lsm6dsx_accel";
>  		iio_dev->info = &st_lsm6dsx_acc_info;
>  
>  		sensor->decimator_mask = ST_LSM6DSX_REG_ACC_DEC_MASK;
> +		scnprintf(sensor->name, sizeof(sensor->name), "%s_accel",
> +			  name);
>  		break;
>  	case ST_LSM6DSX_ID_GYRO:
>  		iio_dev->channels = st_lsm6dsx_gyro_channels;
>  		iio_dev->num_channels = ARRAY_SIZE(st_lsm6dsx_gyro_channels);
> -		iio_dev->name = "lsm6dsx_gyro";
>  		iio_dev->info = &st_lsm6dsx_gyro_info;
>  
>  		sensor->decimator_mask = ST_LSM6DSX_REG_GYRO_DEC_MASK;
> +		scnprintf(sensor->name, sizeof(sensor->name), "%s_gyro",
> +			  name);
>  		break;
>  	default:
>  		return NULL;
>  	}
> +	iio_dev->name = sensor->name;
>  
>  	return iio_dev;
>  }
>  
> -int st_lsm6dsx_probe(struct device *dev, int irq, int hw_id,
> +int st_lsm6dsx_probe(struct device *dev, int irq, int hw_id, const char *name,
>  		     const struct st_lsm6dsx_transfer_function *tf_ops)
>  {
>  	struct st_lsm6dsx_hw *hw;
> @@ -710,7 +714,7 @@ int st_lsm6dsx_probe(struct device *dev, int irq, int hw_id,
>  		return err;
>  
>  	for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
> -		hw->iio_devs[i] = st_lsm6dsx_alloc_iiodev(hw, i);
> +		hw->iio_devs[i] = st_lsm6dsx_alloc_iiodev(hw, i, name);
>  		if (!hw->iio_devs[i])
>  			return -ENOMEM;
>  	}
> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
> index 2e4ed26..09a51cf 100644
> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
> @@ -61,7 +61,7 @@ static int st_lsm6dsx_i2c_probe(struct i2c_client *client,
>  				const struct i2c_device_id *id)
>  {
>  	return st_lsm6dsx_probe(&client->dev, client->irq,
> -				(int)id->driver_data,
> +				(int)id->driver_data, id->name,
>  				&st_lsm6dsx_transfer_fn);
>  }
>  
> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c
> index 1bf4a58..f765a50 100644
> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c
> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c
> @@ -78,7 +78,7 @@ static int st_lsm6dsx_spi_probe(struct spi_device *spi)
>  	const struct spi_device_id *id = spi_get_device_id(spi);
>  
>  	return st_lsm6dsx_probe(&spi->dev, spi->irq,
> -				(int)id->driver_data,
> +				(int)id->driver_data, id->name,
>  				&st_lsm6dsx_transfer_fn);
>  }
>  
>