Re: [PATCH v2 05/13] media: max9286: Move format to subdev state

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Jacopo,

Thank you for the patch.

On Sun, Oct 17, 2021 at 08:24:41PM +0200, Jacopo Mondi wrote:
> Move format handling to the v4l2_subdev state and store it per
> (pad, stream) combination.
> 
> Now that the image format is stored in the subdev state, it can be
> accessed through v4l2_subdev_get_fmt() instead of open-coding it.

Would it be possible to move this to 02/13 in the series ? Storing the
formats in the state doesn't depend on multiplexed streams support, we
could thus merge it early. The current 01/13 would need to be split in
two, with one part to allocate the active state and implement
.init_cfg() without muxed streams support, and another part to add muxed
streams support on top.

> Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
> ---
>  drivers/media/i2c/max9286.c | 85 ++++++++++++-------------------------
>  1 file changed, 27 insertions(+), 58 deletions(-)
> 
> diff --git a/drivers/media/i2c/max9286.c b/drivers/media/i2c/max9286.c
> index 3485478f08a5..e51771d99437 100644
> --- a/drivers/media/i2c/max9286.c
> +++ b/drivers/media/i2c/max9286.c
> @@ -175,8 +175,6 @@ struct max9286_priv {
>  	struct v4l2_ctrl_handler ctrls;
>  	struct v4l2_ctrl *pixelrate;
>  
> -	struct v4l2_mbus_framefmt fmt[MAX9286_N_SINKS];
> -
>  	/* Protects controls and fmt structures */
>  	struct mutex mutex;
>  
> @@ -829,28 +827,18 @@ static int max9286_enum_mbus_code(struct v4l2_subdev *sd,
>  	return 0;
>  }
>  
> -static struct v4l2_mbus_framefmt *
> -max9286_get_pad_format(struct max9286_priv *priv,
> -		       struct v4l2_subdev_state *sd_state,
> -		       unsigned int pad, u32 which)
> -{
> -	switch (which) {
> -	case V4L2_SUBDEV_FORMAT_TRY:
> -		return v4l2_subdev_get_try_format(&priv->sd, sd_state, pad);
> -	case V4L2_SUBDEV_FORMAT_ACTIVE:
> -		return &priv->fmt[pad];
> -	default:
> -		return NULL;
> -	}
> -}
> -
>  static int max9286_set_fmt(struct v4l2_subdev *sd,
>  			   struct v4l2_subdev_state *sd_state,
>  			   struct v4l2_subdev_format *format)
>  {
> -	struct max9286_priv *priv = sd_to_max9286(sd);
> -	struct v4l2_mbus_framefmt *cfg_fmt;
> +	struct v4l2_mbus_framefmt *fmt;
> +	struct v4l2_subdev_state *state;
> +	int ret = 0;
>  
> +	/*
> +	 * Refuse to set format on the multiplexed source pad.
> +	 * Format is propagated from sinks streams to source streams.
> +	 */
>  	if (format->pad == MAX9286_SRC_PAD)
>  		return -EINVAL;
>  
> @@ -866,44 +854,28 @@ static int max9286_set_fmt(struct v4l2_subdev *sd,
>  		break;
>  	}
>  
> -	cfg_fmt = max9286_get_pad_format(priv, sd_state, format->pad,
> -					 format->which);
> -	if (!cfg_fmt)
> -		return -EINVAL;
> -
> -	mutex_lock(&priv->mutex);
> -	*cfg_fmt = format->format;
> -	mutex_unlock(&priv->mutex);
> -
> -	return 0;
> -}
> -
> -static int max9286_get_fmt(struct v4l2_subdev *sd,
> -			   struct v4l2_subdev_state *sd_state,
> -			   struct v4l2_subdev_format *format)
> -{
> -	struct max9286_priv *priv = sd_to_max9286(sd);
> -	struct v4l2_mbus_framefmt *cfg_fmt;
> -	unsigned int pad = format->pad;
> -
> -	/*
> -	 * Multiplexed Stream Support: Support link validation by returning the
> -	 * format of the first bound link. All links must have the same format,
> -	 * as we do not support mixing and matching of cameras connected to the
> -	 * max9286.
> -	 */
> -	if (pad == MAX9286_SRC_PAD)
> -		pad = __ffs(priv->bound_sources);
> +	state = v4l2_subdev_validate_and_lock_state(sd, sd_state);
> +	fmt = v4l2_state_get_stream_format(state, format->pad,
> +					   format->stream);
> +	if (!fmt) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +	*fmt = format->format;
>  
> -	cfg_fmt = max9286_get_pad_format(priv, sd_state, pad, format->which);
> -	if (!cfg_fmt)
> -		return -EINVAL;
> +	/* Propagate format to the other end of the route. */
> +	fmt = v4l2_state_get_opposite_stream_format(state, format->pad,
> +						    format->stream);
> +	if (!fmt) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +	*fmt = format->format;
>  
> -	mutex_lock(&priv->mutex);
> -	format->format = *cfg_fmt;
> -	mutex_unlock(&priv->mutex);
> +out:
> +	v4l2_subdev_unlock_state(state);
>  
> -	return 0;
> +	return ret;
>  }
>  
>  static int max9286_routing_verify(struct max9286_priv *priv,
> @@ -1052,7 +1024,7 @@ static const struct v4l2_subdev_video_ops max9286_video_ops = {
>  static const struct v4l2_subdev_pad_ops max9286_pad_ops = {
>  	.init_cfg	= max9286_init_cfg,
>  	.enum_mbus_code = max9286_enum_mbus_code,
> -	.get_fmt	= max9286_get_fmt,
> +	.get_fmt	= v4l2_subdev_get_fmt,
>  	.set_fmt	= max9286_set_fmt,
>  	.set_routing	= max9286_set_routing,
>  };
> @@ -1092,9 +1064,6 @@ static int max9286_v4l2_register(struct max9286_priv *priv)
>  
>  	/* Configure V4L2 for the MAX9286 itself */
>  
> -	for (i = 0; i < MAX9286_N_SINKS; i++)
> -		priv->fmt[i] = max9286_default_format;
> -
>  	v4l2_i2c_subdev_init(&priv->sd, priv->client, &max9286_subdev_ops);
>  	priv->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
>  			  V4L2_SUBDEV_FL_MULTIPLEXED;
> -- 
> 2.33.0
> 

-- 
Regards,

Laurent Pinchart