On 15/09/2021 02:50, Niklas Söderlund wrote:
> The access to the internal storage of the format rcar_csi2.mf should be
> serialized, extend the exciting lock mutex to also cover this.
Exciting, or existing ;-) I guess it depends on how much you like
mutexes ;-)
> While at it document the mutex.
>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> Reviewed-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
> ---
> drivers/media/platform/rcar-vin/rcar-csi2.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> index a02573dbd5da4f62..2fdfdc38de424c72 100644
> --- a/drivers/media/platform/rcar-vin/rcar-csi2.c
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -370,9 +370,8 @@ struct rcar_csi2 {
> struct v4l2_subdev *remote;
> unsigned int remote_pad;
>
> + struct mutex lock; /* Protects mf and stream_count. */
> struct v4l2_mbus_framefmt mf;
> -
> - struct mutex lock;
> int stream_count;
>
> unsigned short lanes;
> @@ -725,6 +724,8 @@ static int rcsi2_set_pad_format(struct v4l2_subdev *sd,
> struct rcar_csi2 *priv = sd_to_csi2(sd);
> struct v4l2_mbus_framefmt *framefmt;
>
> + mutex_lock(&priv->lock);
> +
> if (!rcsi2_code_to_fmt(format->format.code))
> format->format.code = rcar_csi2_formats[0].code;
>
> @@ -735,6 +736,8 @@ static int rcsi2_set_pad_format(struct v4l2_subdev *sd,
> *framefmt = format->format;
> }
>
> + mutex_unlock(&priv->lock);
> +
> return 0;
> }
>
> @@ -744,11 +747,15 @@ static int rcsi2_get_pad_format(struct v4l2_subdev *sd,
> {
> struct rcar_csi2 *priv = sd_to_csi2(sd);
>
> + mutex_lock(&priv->lock);
> +
> if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> format->format = priv->mf;
> else
> format->format = *v4l2_subdev_get_try_format(sd, sd_state, 0);
>
> + mutex_unlock(&priv->lock);
> +
> return 0;
> }
>
>
