Re: [PATCH v3 2/3] iio: mpl3115: add threshold events support

[Marcelo Schmitt <marcelo.schmitt1@gmail.com>]

Hi Antoni,

v3 looks mostly good to me.
A couple of minor suggestions in addition to Andy's.

On 11/05, Antoni Pokusinski wrote:
> Add support for pressure and temperature rising threshold events. For
> both channels *_en and *_value (in raw units) attributes are exposed.
> 
> Since in write_event_config() the ctrl_reg1.active and ctrl_reg4
> are modified, accessing the data->ctrl_reg{1,4} in set_trigger_state()
> and write_event_config() needs to be now guarded by data->lock.
> Otherwise, it would be possible that 2 concurrent threads executing
> these functions would access the data->ctrl_reg{1,4} at the same time
> and then one would overwrite the other's result.
> 
> Signed-off-by: Antoni Pokusinski <apokusinski01@gmail.com>
> ---
...
> +
> +static int mpl3115_write_thresh(struct iio_dev *indio_dev,
> +				const struct iio_chan_spec *chan,
> +				enum iio_event_type type,
> +				enum iio_event_direction dir,
> +				enum iio_event_info info,
> +				int val, int val2)
> +{
> +	struct mpl3115_data *data = iio_priv(indio_dev);
> +	__be16 tmp;
> +
> +	if (info != IIO_EV_INFO_VALUE)
> +		return -EINVAL;
> +
> +	switch (chan->type) {
> +	case IIO_PRESSURE:
> +		val >>= 1;
> +
> +		if (val < 0 || val > U16_MAX)
Alternatively, could use in_range() for the check.

> +			return -EINVAL;
> +
> +		tmp = cpu_to_be16(val);
> +
> +		return i2c_smbus_write_i2c_block_data(data->client,
> +						      MPL3115_PRESS_TGT,
> +						      sizeof(tmp), (u8 *)&tmp);
> +	case IIO_TEMP:
> +		if (val < S8_MIN || val > S8_MAX)
this could also use in_range().

If you opt for the macro,
#include <linux/minmax.h>

> +			return -EINVAL;
> +
> +		return i2c_smbus_write_byte_data(data->client,
> +						 MPL3115_TEMP_TGT, val);
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +