Re: [PATCH v5 06/15] iio: sx9310: Fixes various memory handling

[Jonathan Cameron <jic23@kernel.org>]

On Mon,  3 Aug 2020 17:58:06 -0600
Daniel Campello <campello@chromium.org> wrote:

> Makes use __aligned(8) to ensure that the timestamp is correctly aligned
> when we call io_push_to_buffers_with_timestamp().
> Also makes use of sizeof() for regmap_bulk_read instead of static value.
> 
> Signed-off-by: Daniel Campello <campello@chromium.org>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Applied

> ---
> 
> Changes in v5:
>  - Really use a pointer to buffer struct on
> iio_push_to_buffers_with_timestamp().
> 
> Changes in v4:
>  - Use pointer to buffer struct on iio_push_to_buffers_with_timestamp().
> 
> Changes in v3:
>  - Changed buffer to struct type to align timestamp memory properly.
> 
> Changes in v2:
>  - Fixed commit message from "iio: sx9310: Align memory"
> 
>  drivers/iio/proximity/sx9310.c | 13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/iio/proximity/sx9310.c b/drivers/iio/proximity/sx9310.c
> index 66ecdd309e0ddc..127b1ba79e2dea 100644
> --- a/drivers/iio/proximity/sx9310.c
> +++ b/drivers/iio/proximity/sx9310.c
> @@ -132,8 +132,11 @@ struct sx9310_data {
>  	 */
>  	bool prox_stat[SX9310_NUM_CHANNELS];
>  	bool trigger_enabled;
> -	__be16 buffer[SX9310_NUM_CHANNELS +
> -		      4]; /* 64-bit data + 64-bit timestamp */
> +	/* Ensure correct alignment of timestamp when present. */
> +	struct {
> +		__be16 channels[SX9310_NUM_CHANNELS];
> +		s64 ts __aligned(8);
> +	} buffer;
>  	/* Remember enabled channels and sample rate during suspend. */
>  	unsigned int suspend_ctrl0;
>  	struct completion completion;
> @@ -344,7 +347,7 @@ static int sx9310_read_prox_data(struct sx9310_data *data,
>  	if (ret < 0)
>  		return ret;
>  
> -	return regmap_bulk_read(data->regmap, chan->address, val, 2);
> +	return regmap_bulk_read(data->regmap, chan->address, val, sizeof(*val));
>  }
>  
>  /*
> @@ -694,10 +697,10 @@ static irqreturn_t sx9310_trigger_handler(int irq, void *private)
>  		if (ret < 0)
>  			goto out;
>  
> -		data->buffer[i++] = val;
> +		data->buffer.channels[i++] = val;
>  	}
>  
> -	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
> +	iio_push_to_buffers_with_timestamp(indio_dev, &data->buffer,
>  					   pf->timestamp);
>  
>  out: