[PATCH 1/2] media: staging: imx: request mbus_config in csi_start

[Frank Li]

On Wed, Nov 05, 2025 at 04:18:49PM +0100, Michael Tretter wrote:
> Request the upstream mbus_config in csi_start, which starts the stream,
> instead of caching it in link_validate.
>
> This allows to get rid of the mbus_cfg field in the struct csi_priv and
> avoids state in the driver.
>
> Signed-off-by: Michael Tretter <m.tretter at pengutronix.de>
> Fixes: 4a34ec8e470c ("[media] media: imx: Add CSI subdev driver")
> Cc: stable at vger.kernel.org
> ---

Reviewed-by: Frank Li <Frank.Li at nxp.com>

>  drivers/staging/media/imx/imx-media-csi.c | 40 ++++++++++++++++++-------------
>  1 file changed, 24 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
> index fd7e37d803e7..55a7d8f38465 100644
> --- a/drivers/staging/media/imx/imx-media-csi.c
> +++ b/drivers/staging/media/imx/imx-media-csi.c
> @@ -97,9 +97,6 @@ struct csi_priv {
>  	/* the mipi virtual channel number at link validate */
>  	int vc_num;
>
> -	/* media bus config of the upstream subdevice CSI is receiving from */
> -	struct v4l2_mbus_config mbus_cfg;
> -
>  	spinlock_t irqlock; /* protect eof_irq handler */
>  	struct timer_list eof_timeout_timer;
>  	int eof_irq;
> @@ -403,7 +400,8 @@ static void csi_idmac_unsetup_vb2_buf(struct csi_priv *priv,
>  }
>
>  /* init the SMFC IDMAC channel */
> -static int csi_idmac_setup_channel(struct csi_priv *priv)
> +static int csi_idmac_setup_channel(struct csi_priv *priv,
> +				   struct v4l2_mbus_config *mbus_cfg)
>  {
>  	struct imx_media_video_dev *vdev = priv->vdev;
>  	const struct imx_media_pixfmt *incc;
> @@ -432,7 +430,7 @@ static int csi_idmac_setup_channel(struct csi_priv *priv)
>  	image.phys0 = phys[0];
>  	image.phys1 = phys[1];
>
> -	passthrough = requires_passthrough(&priv->mbus_cfg, infmt, incc);
> +	passthrough = requires_passthrough(mbus_cfg, infmt, incc);
>  	passthrough_cycles = 1;
>
>  	/*
> @@ -572,11 +570,12 @@ static void csi_idmac_unsetup(struct csi_priv *priv,
>  	csi_idmac_unsetup_vb2_buf(priv, state);
>  }
>
> -static int csi_idmac_setup(struct csi_priv *priv)
> +static int csi_idmac_setup(struct csi_priv *priv,
> +			   struct v4l2_mbus_config *mbus_cfg)
>  {
>  	int ret;
>
> -	ret = csi_idmac_setup_channel(priv);
> +	ret = csi_idmac_setup_channel(priv, mbus_cfg);
>  	if (ret)
>  		return ret;
>
> @@ -595,7 +594,8 @@ static int csi_idmac_setup(struct csi_priv *priv)
>  	return 0;
>  }
>
> -static int csi_idmac_start(struct csi_priv *priv)
> +static int csi_idmac_start(struct csi_priv *priv,
> +			   struct v4l2_mbus_config *mbus_cfg)
>  {
>  	struct imx_media_video_dev *vdev = priv->vdev;
>  	int ret;
> @@ -619,7 +619,7 @@ static int csi_idmac_start(struct csi_priv *priv)
>  	priv->last_eof = false;
>  	priv->nfb4eof = false;
>
> -	ret = csi_idmac_setup(priv);
> +	ret = csi_idmac_setup(priv, mbus_cfg);
>  	if (ret) {
>  		v4l2_err(&priv->sd, "csi_idmac_setup failed: %d\n", ret);
>  		goto out_free_dma_buf;
> @@ -701,7 +701,8 @@ static void csi_idmac_stop(struct csi_priv *priv)
>  }
>
>  /* Update the CSI whole sensor and active windows */
> -static int csi_setup(struct csi_priv *priv)
> +static int csi_setup(struct csi_priv *priv,
> +		     struct v4l2_mbus_config *mbus_cfg)
>  {
>  	struct v4l2_mbus_framefmt *infmt, *outfmt;
>  	const struct imx_media_pixfmt *incc;
> @@ -719,7 +720,7 @@ static int csi_setup(struct csi_priv *priv)
>  	 * if cycles is set, we need to handle this over multiple cycles as
>  	 * generic/bayer data
>  	 */
> -	if (is_parallel_bus(&priv->mbus_cfg) && incc->cycles) {
> +	if (is_parallel_bus(mbus_cfg) && incc->cycles) {
>  		if_fmt.width *= incc->cycles;
>  		crop.width *= incc->cycles;
>  	}
> @@ -730,7 +731,7 @@ static int csi_setup(struct csi_priv *priv)
>  			     priv->crop.width == 2 * priv->compose.width,
>  			     priv->crop.height == 2 * priv->compose.height);
>
> -	ipu_csi_init_interface(priv->csi, &priv->mbus_cfg, &if_fmt, outfmt);
> +	ipu_csi_init_interface(priv->csi, mbus_cfg, &if_fmt, outfmt);
>
>  	ipu_csi_set_dest(priv->csi, priv->dest);
>
> @@ -745,9 +746,17 @@ static int csi_setup(struct csi_priv *priv)
>
>  static int csi_start(struct csi_priv *priv)
>  {
> +	struct v4l2_mbus_config mbus_cfg = { .type = 0 };
>  	struct v4l2_fract *input_fi, *output_fi;
>  	int ret;
>
> +	ret = csi_get_upstream_mbus_config(priv, &mbus_cfg);
> +	if (ret) {
> +		v4l2_err(&priv->sd,
> +			 "failed to get upstream media bus configuration\n");
> +		return ret;
> +	}
> +
>  	input_fi = &priv->frame_interval[CSI_SINK_PAD];
>  	output_fi = &priv->frame_interval[priv->active_output_pad];
>
> @@ -758,7 +767,7 @@ static int csi_start(struct csi_priv *priv)
>  		return ret;
>
>  	/* Skip first few frames from a BT.656 source */
> -	if (priv->mbus_cfg.type == V4L2_MBUS_BT656) {
> +	if (mbus_cfg.type == V4L2_MBUS_BT656) {
>  		u32 delay_usec, bad_frames = 20;
>
>  		delay_usec = DIV_ROUND_UP_ULL((u64)USEC_PER_SEC *
> @@ -769,12 +778,12 @@ static int csi_start(struct csi_priv *priv)
>  	}
>
>  	if (priv->dest == IPU_CSI_DEST_IDMAC) {
> -		ret = csi_idmac_start(priv);
> +		ret = csi_idmac_start(priv, &mbus_cfg);
>  		if (ret)
>  			goto stop_upstream;
>  	}
>
> -	ret = csi_setup(priv);
> +	ret = csi_setup(priv, &mbus_cfg);
>  	if (ret)
>  		goto idmac_stop;
>
> @@ -1138,7 +1147,6 @@ static int csi_link_validate(struct v4l2_subdev *sd,
>
>  	mutex_lock(&priv->lock);
>
> -	priv->mbus_cfg = mbus_cfg;
>  	is_csi2 = !is_parallel_bus(&mbus_cfg);
>  	if (is_csi2) {
>  		/*
>
> --
> 2.47.3
>