diff mbox series

[v3,3/3] media: stm32-dcmi: add support of several sub-devices

Message ID 1562082779-31165-4-git-send-email-hugues.fruchet@st.com (mailing list archive)
State New, archived
Headers show
Series DCMI bridge support | expand

Commit Message

Hugues FRUCHET July 2, 2019, 3:52 p.m. UTC
Add support of several sub-devices within pipeline instead
of a single one.
This allows to support a CSI-2 camera sensor connected
through a CSI-2 to parallel bridge.

Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
---
 drivers/media/platform/stm32/stm32-dcmi.c | 204 +++++++++++++++++++++++++++---
 1 file changed, 186 insertions(+), 18 deletions(-)

Comments

Hans Verkuil July 25, 2019, 11:40 a.m. UTC | #1
On 7/2/19 5:52 PM, Hugues Fruchet wrote:
> Add support of several sub-devices within pipeline instead
> of a single one.
> This allows to support a CSI-2 camera sensor connected
> through a CSI-2 to parallel bridge.
> 
> Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
> ---
>  drivers/media/platform/stm32/stm32-dcmi.c | 204 +++++++++++++++++++++++++++---
>  1 file changed, 186 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
> index 6f37617..6921e6b 100644
> --- a/drivers/media/platform/stm32/stm32-dcmi.c
> +++ b/drivers/media/platform/stm32/stm32-dcmi.c
> @@ -172,6 +172,7 @@ struct stm32_dcmi {
>  
>  	struct media_device		mdev;
>  	struct media_pad		vid_cap_pad;
> +	struct media_pipeline		pipeline;
>  };
>  
>  static inline struct stm32_dcmi *notifier_to_dcmi(struct v4l2_async_notifier *n)
> @@ -583,6 +584,131 @@ static void dcmi_buf_queue(struct vb2_buffer *vb)
>  	spin_unlock_irq(&dcmi->irqlock);
>  }
>  
> +static struct media_entity *dcmi_find_source(struct stm32_dcmi *dcmi)
> +{
> +	struct media_entity *entity = &dcmi->vdev->entity;
> +	struct media_pad *pad;
> +
> +	/* Walk searching for entity having no sink */
> +	while (1) {
> +		pad = &entity->pads[0];
> +		if (!(pad->flags & MEDIA_PAD_FL_SINK))
> +			break;
> +
> +		pad = media_entity_remote_pad(pad);
> +		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
> +			break;
> +
> +		entity = pad->entity;
> +	}
> +
> +	return entity;
> +}
> +
> +static int dcmi_pipeline_s_fmt(struct stm32_dcmi *dcmi,
> +			       struct v4l2_subdev_pad_config *pad_cfg,
> +			       struct v4l2_subdev_format *format)
> +{
> +	struct media_entity *entity = &dcmi->entity.source->entity;
> +	struct v4l2_subdev *subdev;
> +	struct media_pad *sink_pad = NULL;
> +	struct media_pad *src_pad = NULL;
> +	struct media_pad *pad = NULL;
> +	struct v4l2_subdev_format fmt = *format;
> +	bool found = false;
> +	int ret;
> +
> +	/*
> +	 * Starting from sensor subdevice, walk within
> +	 * pipeline and set format on each subdevice
> +	 */
> +	while (1) {
> +		unsigned int i;
> +
> +		/* Search if current entity has a source pad */
> +		for (i = 0; i < entity->num_pads; i++) {
> +			pad = &entity->pads[i];
> +			if (pad->flags & MEDIA_PAD_FL_SOURCE) {
> +				src_pad = pad;
> +				found = true;
> +				break;
> +			}
> +		}
> +		if (!found)
> +			break;
> +
> +		subdev = media_entity_to_v4l2_subdev(entity);
> +
> +		/* Propagate format on sink pad if any, otherwise source pad */
> +		if (sink_pad)
> +			pad = sink_pad;
> +
> +		dev_dbg(dcmi->dev, "%s[%d] pad format set to 0x%x %ux%u\n",
> +			subdev->name, pad->index, format->format.code,
> +			format->format.width, format->format.height);
> +
> +		fmt.pad = pad->index;
> +		ret = v4l2_subdev_call(subdev, pad, set_fmt, pad_cfg, &fmt);
> +		if (ret < 0)
> +			return ret;
> +
> +		/* Walk to next entity */
> +		sink_pad = media_entity_remote_pad(src_pad);
> +		if (!sink_pad || !is_media_entity_v4l2_subdev(sink_pad->entity))
> +			break;
> +
> +		entity = sink_pad->entity;
> +	}
> +	*format = fmt;
> +
> +	return 0;
> +}
> +
> +static int dcmi_pipeline_s_stream(struct stm32_dcmi *dcmi, int state)
> +{
> +	struct media_entity *entity = &dcmi->vdev->entity;
> +	struct v4l2_subdev *subdev;
> +	struct media_pad *pad;
> +	int ret;
> +
> +	/* Start/stop all entities within pipeline */
> +	while (1) {
> +		pad = &entity->pads[0];
> +		if (!(pad->flags & MEDIA_PAD_FL_SINK))
> +			break;
> +
> +		pad = media_entity_remote_pad(pad);
> +		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
> +			break;
> +
> +		entity = pad->entity;
> +		subdev = media_entity_to_v4l2_subdev(entity);
> +
> +		ret = v4l2_subdev_call(subdev, video, s_stream, state);
> +		if (ret < 0 && ret != -ENOIOCTLCMD) {
> +			dev_err(dcmi->dev, "%s: %s failed to %s streaming (%d)\n",
> +				__func__, subdev->name,
> +				state ? "start" : "stop", ret);
> +			return ret;
> +		}
> +
> +		dev_dbg(dcmi->dev, "%s is %s\n",
> +			subdev->name, state ? "started" : "stopped");
> +	}
> +
> +	return 0;
> +}
> +
> +static int dcmi_pipeline_start(struct stm32_dcmi *dcmi)
> +{
> +	return dcmi_pipeline_s_stream(dcmi, 1);
> +}
> +
> +static void dcmi_pipeline_stop(struct stm32_dcmi *dcmi)
> +{
> +	dcmi_pipeline_s_stream(dcmi, 0);
> +}
> +
>  static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>  {
>  	struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
> @@ -597,14 +723,17 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>  		goto err_release_buffers;
>  	}
>  
> -	/* Enable stream on the sub device */
> -	ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 1);
> -	if (ret && ret != -ENOIOCTLCMD) {
> -		dev_err(dcmi->dev, "%s: Failed to start streaming, subdev streamon error",
> -			__func__);
> +	ret = media_pipeline_start(&dcmi->vdev->entity, &dcmi->pipeline);
> +	if (ret < 0) {
> +		dev_err(dcmi->dev, "%s: Failed to start streaming, media pipeline start error (%d)\n",
> +			__func__, ret);
>  		goto err_pm_put;
>  	}
>  
> +	ret = dcmi_pipeline_start(dcmi);
> +	if (ret)
> +		goto err_media_pipeline_stop;
> +
>  	spin_lock_irq(&dcmi->irqlock);
>  
>  	/* Set bus width */
> @@ -676,7 +805,7 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>  	if (ret) {
>  		dev_err(dcmi->dev, "%s: Start streaming failed, cannot start capture\n",
>  			__func__);
> -		goto err_subdev_streamoff;
> +		goto err_pipeline_stop;
>  	}
>  
>  	/* Enable interruptions */
> @@ -687,8 +816,11 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>  
>  	return 0;
>  
> -err_subdev_streamoff:
> -	v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
> +err_pipeline_stop:
> +	dcmi_pipeline_stop(dcmi);
> +
> +err_media_pipeline_stop:
> +	media_pipeline_stop(&dcmi->vdev->entity);
>  
>  err_pm_put:
>  	pm_runtime_put(dcmi->dev);
> @@ -713,13 +845,10 @@ static void dcmi_stop_streaming(struct vb2_queue *vq)
>  {
>  	struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
>  	struct dcmi_buf *buf, *node;
> -	int ret;
>  
> -	/* Disable stream on the sub device */
> -	ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
> -	if (ret && ret != -ENOIOCTLCMD)
> -		dev_err(dcmi->dev, "%s: Failed to stop streaming, subdev streamoff error (%d)\n",
> -			__func__, ret);
> +	dcmi_pipeline_stop(dcmi);
> +
> +	media_pipeline_stop(&dcmi->vdev->entity);
>  
>  	spin_lock_irq(&dcmi->irqlock);
>  
> @@ -937,8 +1066,7 @@ static int dcmi_set_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f)
>  	mf->width = sd_framesize.width;
>  	mf->height = sd_framesize.height;
>  
> -	ret = v4l2_subdev_call(dcmi->entity.source, pad,
> -			       set_fmt, NULL, &format);
> +	ret = dcmi_pipeline_s_fmt(dcmi, NULL, &format);
>  	if (ret < 0)
>  		return ret;
>  
> @@ -1529,7 +1657,20 @@ static int dcmi_graph_notify_complete(struct v4l2_async_notifier *notifier)
>  	struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
>  	int ret;
>  
> +	/*
> +	 * Now that the graph is complete,
> +	 * we search for the source subdevice
> +	 * in order to expose it through V4L2 interface
> +	 */
> +	dcmi->entity.source =
> +		media_entity_to_v4l2_subdev(dcmi_find_source(dcmi));
> +	if (!dcmi->entity.source) {
> +		dev_err(dcmi->dev, "Source subdevice not found\n");
> +		return -ENODEV;
> +	}
> +
>  	dcmi->vdev->ctrl_handler = dcmi->entity.source->ctrl_handler;
> +
>  	ret = dcmi_formats_init(dcmi);
>  	if (ret) {
>  		dev_err(dcmi->dev, "No supported mediabus format found\n");
> @@ -1574,12 +1715,30 @@ static int dcmi_graph_notify_bound(struct v4l2_async_notifier *notifier,
>  				   struct v4l2_async_subdev *asd)
>  {
>  	struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
> +	unsigned int ret;
> +	int src_pad;
>  
>  	dev_dbg(dcmi->dev, "Subdev %s bound\n", subdev->name);
>  
> -	dcmi->entity.source = subdev;
> +	/*
> +	 * Link this sub-device to DCMI, it could be
> +	 * a parallel camera sensor or a bridge
> +	 */
> +	src_pad = media_entity_get_fwnode_pad(&subdev->entity,
> +					      subdev->fwnode,
> +					      MEDIA_PAD_FL_SOURCE);
> +
> +	ret = media_create_pad_link(&subdev->entity, src_pad,
> +				    &dcmi->vdev->entity, 0,
> +				    MEDIA_LNK_FL_IMMUTABLE |
> +				    MEDIA_LNK_FL_ENABLED);
> +	if (ret)
> +		dev_err(dcmi->dev, "Failed to create media pad link with subdev %s\n",
> +			subdev->name);
> +	else
> +		dev_dbg(dcmi->dev, "DCMI is now linked to %s\n", subdev->name);
>  
> -	return 0;
> +	return ret;
>  }
>  
>  static const struct v4l2_async_notifier_operations dcmi_graph_notify_ops = {
> @@ -1639,6 +1798,15 @@ static int dcmi_graph_init(struct stm32_dcmi *dcmi)
>  		return ret;
>  	}
>  
> +	/* Register all the subdev nodes */
> +	ret = v4l2_device_register_subdev_nodes(&dcmi->v4l2_dev);

This shouldn't be needed. Only MC-centric drivers (i.e. where the pipeline
has to be configured by userspace) need to do this.

Otherwise this patch looks good.

Regards,

	Hans

> +	if (ret) {
> +		dev_err(dcmi->dev, "Failed to register subdev nodes\n");
> +		v4l2_async_notifier_unregister(&dcmi->notifier);
> +		of_node_put(dcmi->entity.remote_node);
> +		return ret;
> +	}
> +
>  	return 0;
>  }
>  
>
Benjamin Gaignard July 25, 2019, 2:56 p.m. UTC | #2
Le jeu. 25 juil. 2019 à 13:40, Hans Verkuil <hverkuil@xs4all.nl> a écrit :
>
> On 7/2/19 5:52 PM, Hugues Fruchet wrote:
> > Add support of several sub-devices within pipeline instead
> > of a single one.
> > This allows to support a CSI-2 camera sensor connected
> > through a CSI-2 to parallel bridge.
> >
> > Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
> > ---
> >  drivers/media/platform/stm32/stm32-dcmi.c | 204 +++++++++++++++++++++++++++---
> >  1 file changed, 186 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
> > index 6f37617..6921e6b 100644
> > --- a/drivers/media/platform/stm32/stm32-dcmi.c
> > +++ b/drivers/media/platform/stm32/stm32-dcmi.c
> > @@ -172,6 +172,7 @@ struct stm32_dcmi {
> >
> >       struct media_device             mdev;
> >       struct media_pad                vid_cap_pad;
> > +     struct media_pipeline           pipeline;
> >  };
> >
> >  static inline struct stm32_dcmi *notifier_to_dcmi(struct v4l2_async_notifier *n)
> > @@ -583,6 +584,131 @@ static void dcmi_buf_queue(struct vb2_buffer *vb)
> >       spin_unlock_irq(&dcmi->irqlock);
> >  }
> >
> > +static struct media_entity *dcmi_find_source(struct stm32_dcmi *dcmi)
> > +{
> > +     struct media_entity *entity = &dcmi->vdev->entity;
> > +     struct media_pad *pad;
> > +
> > +     /* Walk searching for entity having no sink */
> > +     while (1) {
> > +             pad = &entity->pads[0];
> > +             if (!(pad->flags & MEDIA_PAD_FL_SINK))
> > +                     break;
> > +
> > +             pad = media_entity_remote_pad(pad);
> > +             if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
> > +                     break;
> > +
> > +             entity = pad->entity;
> > +     }
> > +
> > +     return entity;
> > +}
> > +
> > +static int dcmi_pipeline_s_fmt(struct stm32_dcmi *dcmi,
> > +                            struct v4l2_subdev_pad_config *pad_cfg,
> > +                            struct v4l2_subdev_format *format)
> > +{
> > +     struct media_entity *entity = &dcmi->entity.source->entity;
> > +     struct v4l2_subdev *subdev;
> > +     struct media_pad *sink_pad = NULL;
> > +     struct media_pad *src_pad = NULL;
> > +     struct media_pad *pad = NULL;
> > +     struct v4l2_subdev_format fmt = *format;
> > +     bool found = false;
> > +     int ret;
> > +
> > +     /*
> > +      * Starting from sensor subdevice, walk within
> > +      * pipeline and set format on each subdevice
> > +      */
> > +     while (1) {
> > +             unsigned int i;
> > +
> > +             /* Search if current entity has a source pad */
> > +             for (i = 0; i < entity->num_pads; i++) {
> > +                     pad = &entity->pads[i];
> > +                     if (pad->flags & MEDIA_PAD_FL_SOURCE) {
> > +                             src_pad = pad;
> > +                             found = true;
> > +                             break;
> > +                     }
> > +             }
> > +             if (!found)
> > +                     break;
> > +
> > +             subdev = media_entity_to_v4l2_subdev(entity);
> > +
> > +             /* Propagate format on sink pad if any, otherwise source pad */
> > +             if (sink_pad)
> > +                     pad = sink_pad;
> > +
> > +             dev_dbg(dcmi->dev, "%s[%d] pad format set to 0x%x %ux%u\n",
> > +                     subdev->name, pad->index, format->format.code,
> > +                     format->format.width, format->format.height);
> > +
> > +             fmt.pad = pad->index;
> > +             ret = v4l2_subdev_call(subdev, pad, set_fmt, pad_cfg, &fmt);
> > +             if (ret < 0)
> > +                     return ret;
> > +
> > +             /* Walk to next entity */
> > +             sink_pad = media_entity_remote_pad(src_pad);
> > +             if (!sink_pad || !is_media_entity_v4l2_subdev(sink_pad->entity))
> > +                     break;
> > +
> > +             entity = sink_pad->entity;
> > +     }
> > +     *format = fmt;
> > +
> > +     return 0;
> > +}
> > +
> > +static int dcmi_pipeline_s_stream(struct stm32_dcmi *dcmi, int state)
> > +{
> > +     struct media_entity *entity = &dcmi->vdev->entity;
> > +     struct v4l2_subdev *subdev;
> > +     struct media_pad *pad;
> > +     int ret;
> > +
> > +     /* Start/stop all entities within pipeline */
> > +     while (1) {
> > +             pad = &entity->pads[0];
> > +             if (!(pad->flags & MEDIA_PAD_FL_SINK))
> > +                     break;
> > +
> > +             pad = media_entity_remote_pad(pad);
> > +             if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
> > +                     break;
> > +
> > +             entity = pad->entity;
> > +             subdev = media_entity_to_v4l2_subdev(entity);
> > +
> > +             ret = v4l2_subdev_call(subdev, video, s_stream, state);
> > +             if (ret < 0 && ret != -ENOIOCTLCMD) {
> > +                     dev_err(dcmi->dev, "%s: %s failed to %s streaming (%d)\n",
> > +                             __func__, subdev->name,
> > +                             state ? "start" : "stop", ret);
> > +                     return ret;
> > +             }
> > +
> > +             dev_dbg(dcmi->dev, "%s is %s\n",
> > +                     subdev->name, state ? "started" : "stopped");
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int dcmi_pipeline_start(struct stm32_dcmi *dcmi)
> > +{
> > +     return dcmi_pipeline_s_stream(dcmi, 1);
> > +}
> > +
> > +static void dcmi_pipeline_stop(struct stm32_dcmi *dcmi)
> > +{
> > +     dcmi_pipeline_s_stream(dcmi, 0);
> > +}
> > +
> >  static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
> >  {
> >       struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
> > @@ -597,14 +723,17 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
> >               goto err_release_buffers;
> >       }
> >
> > -     /* Enable stream on the sub device */
> > -     ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 1);
> > -     if (ret && ret != -ENOIOCTLCMD) {
> > -             dev_err(dcmi->dev, "%s: Failed to start streaming, subdev streamon error",
> > -                     __func__);
> > +     ret = media_pipeline_start(&dcmi->vdev->entity, &dcmi->pipeline);
> > +     if (ret < 0) {
> > +             dev_err(dcmi->dev, "%s: Failed to start streaming, media pipeline start error (%d)\n",
> > +                     __func__, ret);
> >               goto err_pm_put;
> >       }
> >
> > +     ret = dcmi_pipeline_start(dcmi);
> > +     if (ret)
> > +             goto err_media_pipeline_stop;
> > +
> >       spin_lock_irq(&dcmi->irqlock);
> >
> >       /* Set bus width */
> > @@ -676,7 +805,7 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
> >       if (ret) {
> >               dev_err(dcmi->dev, "%s: Start streaming failed, cannot start capture\n",
> >                       __func__);
> > -             goto err_subdev_streamoff;
> > +             goto err_pipeline_stop;
> >       }
> >
> >       /* Enable interruptions */
> > @@ -687,8 +816,11 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
> >
> >       return 0;
> >
> > -err_subdev_streamoff:
> > -     v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
> > +err_pipeline_stop:
> > +     dcmi_pipeline_stop(dcmi);
> > +
> > +err_media_pipeline_stop:
> > +     media_pipeline_stop(&dcmi->vdev->entity);
> >
> >  err_pm_put:
> >       pm_runtime_put(dcmi->dev);
> > @@ -713,13 +845,10 @@ static void dcmi_stop_streaming(struct vb2_queue *vq)
> >  {
> >       struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
> >       struct dcmi_buf *buf, *node;
> > -     int ret;
> >
> > -     /* Disable stream on the sub device */
> > -     ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
> > -     if (ret && ret != -ENOIOCTLCMD)
> > -             dev_err(dcmi->dev, "%s: Failed to stop streaming, subdev streamoff error (%d)\n",
> > -                     __func__, ret);
> > +     dcmi_pipeline_stop(dcmi);
> > +
> > +     media_pipeline_stop(&dcmi->vdev->entity);
> >
> >       spin_lock_irq(&dcmi->irqlock);
> >
> > @@ -937,8 +1066,7 @@ static int dcmi_set_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f)
> >       mf->width = sd_framesize.width;
> >       mf->height = sd_framesize.height;
> >
> > -     ret = v4l2_subdev_call(dcmi->entity.source, pad,
> > -                            set_fmt, NULL, &format);
> > +     ret = dcmi_pipeline_s_fmt(dcmi, NULL, &format);
> >       if (ret < 0)
> >               return ret;
> >
> > @@ -1529,7 +1657,20 @@ static int dcmi_graph_notify_complete(struct v4l2_async_notifier *notifier)
> >       struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
> >       int ret;
> >
> > +     /*
> > +      * Now that the graph is complete,
> > +      * we search for the source subdevice
> > +      * in order to expose it through V4L2 interface
> > +      */
> > +     dcmi->entity.source =
> > +             media_entity_to_v4l2_subdev(dcmi_find_source(dcmi));
> > +     if (!dcmi->entity.source) {
> > +             dev_err(dcmi->dev, "Source subdevice not found\n");
> > +             return -ENODEV;
> > +     }
> > +
> >       dcmi->vdev->ctrl_handler = dcmi->entity.source->ctrl_handler;
> > +
> >       ret = dcmi_formats_init(dcmi);
> >       if (ret) {
> >               dev_err(dcmi->dev, "No supported mediabus format found\n");
> > @@ -1574,12 +1715,30 @@ static int dcmi_graph_notify_bound(struct v4l2_async_notifier *notifier,
> >                                  struct v4l2_async_subdev *asd)
> >  {
> >       struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
> > +     unsigned int ret;
> > +     int src_pad;
> >
> >       dev_dbg(dcmi->dev, "Subdev %s bound\n", subdev->name);
> >
> > -     dcmi->entity.source = subdev;
> > +     /*
> > +      * Link this sub-device to DCMI, it could be
> > +      * a parallel camera sensor or a bridge
> > +      */
> > +     src_pad = media_entity_get_fwnode_pad(&subdev->entity,
> > +                                           subdev->fwnode,
> > +                                           MEDIA_PAD_FL_SOURCE);
> > +
> > +     ret = media_create_pad_link(&subdev->entity, src_pad,
> > +                                 &dcmi->vdev->entity, 0,
> > +                                 MEDIA_LNK_FL_IMMUTABLE |
> > +                                 MEDIA_LNK_FL_ENABLED);
> > +     if (ret)
> > +             dev_err(dcmi->dev, "Failed to create media pad link with subdev %s\n",
> > +                     subdev->name);
> > +     else
> > +             dev_dbg(dcmi->dev, "DCMI is now linked to %s\n", subdev->name);
> >
> > -     return 0;
> > +     return ret;
> >  }
> >
> >  static const struct v4l2_async_notifier_operations dcmi_graph_notify_ops = {
> > @@ -1639,6 +1798,15 @@ static int dcmi_graph_init(struct stm32_dcmi *dcmi)
> >               return ret;
> >       }
> >
> > +     /* Register all the subdev nodes */
> > +     ret = v4l2_device_register_subdev_nodes(&dcmi->v4l2_dev);
>
> This shouldn't be needed. Only MC-centric drivers (i.e. where the pipeline
> has to be configured by userspace) need to do this.

Hi Hans,
I think this point has been discussed in this thread
https://www.spinics.net/lists/linux-media/msg153417.html

In short : since the hardware only offer one possible path we don't expose
the configuration to userland and let DCMI driver configure the
subdevice (like bridge).

Benjamin

>
> Otherwise this patch looks good.
>
> Regards,
>
>         Hans
>
> > +     if (ret) {
> > +             dev_err(dcmi->dev, "Failed to register subdev nodes\n");
> > +             v4l2_async_notifier_unregister(&dcmi->notifier);
> > +             of_node_put(dcmi->entity.remote_node);
> > +             return ret;
> > +     }
> > +
> >       return 0;
> >  }
> >
> >
>
Hans Verkuil July 25, 2019, 3:09 p.m. UTC | #3
On 7/25/19 4:56 PM, Benjamin Gaignard wrote:
> Le jeu. 25 juil. 2019 à 13:40, Hans Verkuil <hverkuil@xs4all.nl> a écrit :
>>
>> On 7/2/19 5:52 PM, Hugues Fruchet wrote:
>>> Add support of several sub-devices within pipeline instead
>>> of a single one.
>>> This allows to support a CSI-2 camera sensor connected
>>> through a CSI-2 to parallel bridge.
>>>
>>> Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
>>> ---
>>>  drivers/media/platform/stm32/stm32-dcmi.c | 204 +++++++++++++++++++++++++++---
>>>  1 file changed, 186 insertions(+), 18 deletions(-)
>>>
>>> diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
>>> index 6f37617..6921e6b 100644
>>> --- a/drivers/media/platform/stm32/stm32-dcmi.c
>>> +++ b/drivers/media/platform/stm32/stm32-dcmi.c
>>> @@ -172,6 +172,7 @@ struct stm32_dcmi {
>>>
>>>       struct media_device             mdev;
>>>       struct media_pad                vid_cap_pad;
>>> +     struct media_pipeline           pipeline;
>>>  };
>>>
>>>  static inline struct stm32_dcmi *notifier_to_dcmi(struct v4l2_async_notifier *n)
>>> @@ -583,6 +584,131 @@ static void dcmi_buf_queue(struct vb2_buffer *vb)
>>>       spin_unlock_irq(&dcmi->irqlock);
>>>  }
>>>
>>> +static struct media_entity *dcmi_find_source(struct stm32_dcmi *dcmi)
>>> +{
>>> +     struct media_entity *entity = &dcmi->vdev->entity;
>>> +     struct media_pad *pad;
>>> +
>>> +     /* Walk searching for entity having no sink */
>>> +     while (1) {
>>> +             pad = &entity->pads[0];
>>> +             if (!(pad->flags & MEDIA_PAD_FL_SINK))
>>> +                     break;
>>> +
>>> +             pad = media_entity_remote_pad(pad);
>>> +             if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
>>> +                     break;
>>> +
>>> +             entity = pad->entity;
>>> +     }
>>> +
>>> +     return entity;
>>> +}
>>> +
>>> +static int dcmi_pipeline_s_fmt(struct stm32_dcmi *dcmi,
>>> +                            struct v4l2_subdev_pad_config *pad_cfg,
>>> +                            struct v4l2_subdev_format *format)
>>> +{
>>> +     struct media_entity *entity = &dcmi->entity.source->entity;
>>> +     struct v4l2_subdev *subdev;
>>> +     struct media_pad *sink_pad = NULL;
>>> +     struct media_pad *src_pad = NULL;
>>> +     struct media_pad *pad = NULL;
>>> +     struct v4l2_subdev_format fmt = *format;
>>> +     bool found = false;
>>> +     int ret;
>>> +
>>> +     /*
>>> +      * Starting from sensor subdevice, walk within
>>> +      * pipeline and set format on each subdevice
>>> +      */
>>> +     while (1) {
>>> +             unsigned int i;
>>> +
>>> +             /* Search if current entity has a source pad */
>>> +             for (i = 0; i < entity->num_pads; i++) {
>>> +                     pad = &entity->pads[i];
>>> +                     if (pad->flags & MEDIA_PAD_FL_SOURCE) {
>>> +                             src_pad = pad;
>>> +                             found = true;
>>> +                             break;
>>> +                     }
>>> +             }
>>> +             if (!found)
>>> +                     break;
>>> +
>>> +             subdev = media_entity_to_v4l2_subdev(entity);
>>> +
>>> +             /* Propagate format on sink pad if any, otherwise source pad */
>>> +             if (sink_pad)
>>> +                     pad = sink_pad;
>>> +
>>> +             dev_dbg(dcmi->dev, "%s[%d] pad format set to 0x%x %ux%u\n",
>>> +                     subdev->name, pad->index, format->format.code,
>>> +                     format->format.width, format->format.height);
>>> +
>>> +             fmt.pad = pad->index;
>>> +             ret = v4l2_subdev_call(subdev, pad, set_fmt, pad_cfg, &fmt);
>>> +             if (ret < 0)
>>> +                     return ret;
>>> +
>>> +             /* Walk to next entity */
>>> +             sink_pad = media_entity_remote_pad(src_pad);
>>> +             if (!sink_pad || !is_media_entity_v4l2_subdev(sink_pad->entity))
>>> +                     break;
>>> +
>>> +             entity = sink_pad->entity;
>>> +     }
>>> +     *format = fmt;
>>> +
>>> +     return 0;
>>> +}
>>> +
>>> +static int dcmi_pipeline_s_stream(struct stm32_dcmi *dcmi, int state)
>>> +{
>>> +     struct media_entity *entity = &dcmi->vdev->entity;
>>> +     struct v4l2_subdev *subdev;
>>> +     struct media_pad *pad;
>>> +     int ret;
>>> +
>>> +     /* Start/stop all entities within pipeline */
>>> +     while (1) {
>>> +             pad = &entity->pads[0];
>>> +             if (!(pad->flags & MEDIA_PAD_FL_SINK))
>>> +                     break;
>>> +
>>> +             pad = media_entity_remote_pad(pad);
>>> +             if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
>>> +                     break;
>>> +
>>> +             entity = pad->entity;
>>> +             subdev = media_entity_to_v4l2_subdev(entity);
>>> +
>>> +             ret = v4l2_subdev_call(subdev, video, s_stream, state);
>>> +             if (ret < 0 && ret != -ENOIOCTLCMD) {
>>> +                     dev_err(dcmi->dev, "%s: %s failed to %s streaming (%d)\n",
>>> +                             __func__, subdev->name,
>>> +                             state ? "start" : "stop", ret);
>>> +                     return ret;
>>> +             }
>>> +
>>> +             dev_dbg(dcmi->dev, "%s is %s\n",
>>> +                     subdev->name, state ? "started" : "stopped");
>>> +     }
>>> +
>>> +     return 0;
>>> +}
>>> +
>>> +static int dcmi_pipeline_start(struct stm32_dcmi *dcmi)
>>> +{
>>> +     return dcmi_pipeline_s_stream(dcmi, 1);
>>> +}
>>> +
>>> +static void dcmi_pipeline_stop(struct stm32_dcmi *dcmi)
>>> +{
>>> +     dcmi_pipeline_s_stream(dcmi, 0);
>>> +}
>>> +
>>>  static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>  {
>>>       struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
>>> @@ -597,14 +723,17 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>               goto err_release_buffers;
>>>       }
>>>
>>> -     /* Enable stream on the sub device */
>>> -     ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 1);
>>> -     if (ret && ret != -ENOIOCTLCMD) {
>>> -             dev_err(dcmi->dev, "%s: Failed to start streaming, subdev streamon error",
>>> -                     __func__);
>>> +     ret = media_pipeline_start(&dcmi->vdev->entity, &dcmi->pipeline);
>>> +     if (ret < 0) {
>>> +             dev_err(dcmi->dev, "%s: Failed to start streaming, media pipeline start error (%d)\n",
>>> +                     __func__, ret);
>>>               goto err_pm_put;
>>>       }
>>>
>>> +     ret = dcmi_pipeline_start(dcmi);
>>> +     if (ret)
>>> +             goto err_media_pipeline_stop;
>>> +
>>>       spin_lock_irq(&dcmi->irqlock);
>>>
>>>       /* Set bus width */
>>> @@ -676,7 +805,7 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>       if (ret) {
>>>               dev_err(dcmi->dev, "%s: Start streaming failed, cannot start capture\n",
>>>                       __func__);
>>> -             goto err_subdev_streamoff;
>>> +             goto err_pipeline_stop;
>>>       }
>>>
>>>       /* Enable interruptions */
>>> @@ -687,8 +816,11 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>
>>>       return 0;
>>>
>>> -err_subdev_streamoff:
>>> -     v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
>>> +err_pipeline_stop:
>>> +     dcmi_pipeline_stop(dcmi);
>>> +
>>> +err_media_pipeline_stop:
>>> +     media_pipeline_stop(&dcmi->vdev->entity);
>>>
>>>  err_pm_put:
>>>       pm_runtime_put(dcmi->dev);
>>> @@ -713,13 +845,10 @@ static void dcmi_stop_streaming(struct vb2_queue *vq)
>>>  {
>>>       struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
>>>       struct dcmi_buf *buf, *node;
>>> -     int ret;
>>>
>>> -     /* Disable stream on the sub device */
>>> -     ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
>>> -     if (ret && ret != -ENOIOCTLCMD)
>>> -             dev_err(dcmi->dev, "%s: Failed to stop streaming, subdev streamoff error (%d)\n",
>>> -                     __func__, ret);
>>> +     dcmi_pipeline_stop(dcmi);
>>> +
>>> +     media_pipeline_stop(&dcmi->vdev->entity);
>>>
>>>       spin_lock_irq(&dcmi->irqlock);
>>>
>>> @@ -937,8 +1066,7 @@ static int dcmi_set_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f)
>>>       mf->width = sd_framesize.width;
>>>       mf->height = sd_framesize.height;
>>>
>>> -     ret = v4l2_subdev_call(dcmi->entity.source, pad,
>>> -                            set_fmt, NULL, &format);
>>> +     ret = dcmi_pipeline_s_fmt(dcmi, NULL, &format);
>>>       if (ret < 0)
>>>               return ret;
>>>
>>> @@ -1529,7 +1657,20 @@ static int dcmi_graph_notify_complete(struct v4l2_async_notifier *notifier)
>>>       struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
>>>       int ret;
>>>
>>> +     /*
>>> +      * Now that the graph is complete,
>>> +      * we search for the source subdevice
>>> +      * in order to expose it through V4L2 interface
>>> +      */
>>> +     dcmi->entity.source =
>>> +             media_entity_to_v4l2_subdev(dcmi_find_source(dcmi));
>>> +     if (!dcmi->entity.source) {
>>> +             dev_err(dcmi->dev, "Source subdevice not found\n");
>>> +             return -ENODEV;
>>> +     }
>>> +
>>>       dcmi->vdev->ctrl_handler = dcmi->entity.source->ctrl_handler;
>>> +
>>>       ret = dcmi_formats_init(dcmi);
>>>       if (ret) {
>>>               dev_err(dcmi->dev, "No supported mediabus format found\n");
>>> @@ -1574,12 +1715,30 @@ static int dcmi_graph_notify_bound(struct v4l2_async_notifier *notifier,
>>>                                  struct v4l2_async_subdev *asd)
>>>  {
>>>       struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
>>> +     unsigned int ret;
>>> +     int src_pad;
>>>
>>>       dev_dbg(dcmi->dev, "Subdev %s bound\n", subdev->name);
>>>
>>> -     dcmi->entity.source = subdev;
>>> +     /*
>>> +      * Link this sub-device to DCMI, it could be
>>> +      * a parallel camera sensor or a bridge
>>> +      */
>>> +     src_pad = media_entity_get_fwnode_pad(&subdev->entity,
>>> +                                           subdev->fwnode,
>>> +                                           MEDIA_PAD_FL_SOURCE);
>>> +
>>> +     ret = media_create_pad_link(&subdev->entity, src_pad,
>>> +                                 &dcmi->vdev->entity, 0,
>>> +                                 MEDIA_LNK_FL_IMMUTABLE |
>>> +                                 MEDIA_LNK_FL_ENABLED);
>>> +     if (ret)
>>> +             dev_err(dcmi->dev, "Failed to create media pad link with subdev %s\n",
>>> +                     subdev->name);
>>> +     else
>>> +             dev_dbg(dcmi->dev, "DCMI is now linked to %s\n", subdev->name);
>>>
>>> -     return 0;
>>> +     return ret;
>>>  }
>>>
>>>  static const struct v4l2_async_notifier_operations dcmi_graph_notify_ops = {
>>> @@ -1639,6 +1798,15 @@ static int dcmi_graph_init(struct stm32_dcmi *dcmi)
>>>               return ret;
>>>       }
>>>
>>> +     /* Register all the subdev nodes */
>>> +     ret = v4l2_device_register_subdev_nodes(&dcmi->v4l2_dev);
>>
>> This shouldn't be needed. Only MC-centric drivers (i.e. where the pipeline
>> has to be configured by userspace) need to do this.
> 
> Hi Hans,
> I think this point has been discussed in this thread
> https://www.spinics.net/lists/linux-media/msg153417.html
> 
> In short : since the hardware only offer one possible path we don't expose
> the configuration to userland and let DCMI driver configure the
> subdevice (like bridge).

Yes, and I agree completely. But why then do you register v4l-subdevX devices?
That's not needed for this driver.

Regards,

	Hans

> 
> Benjamin
> 
>>
>> Otherwise this patch looks good.
>>
>> Regards,
>>
>>         Hans
>>
>>> +     if (ret) {
>>> +             dev_err(dcmi->dev, "Failed to register subdev nodes\n");
>>> +             v4l2_async_notifier_unregister(&dcmi->notifier);
>>> +             of_node_put(dcmi->entity.remote_node);
>>> +             return ret;
>>> +     }
>>> +
>>>       return 0;
>>>  }
>>>
>>>
>>
Hugues FRUCHET July 31, 2019, 1:05 p.m. UTC | #4
Hi Hans,

I've just pushed v4 with subdev nodes registry removal as per your 
suggestion.

On 7/25/19 5:09 PM, Hans Verkuil wrote:
> On 7/25/19 4:56 PM, Benjamin Gaignard wrote:
>> Le jeu. 25 juil. 2019 à 13:40, Hans Verkuil <hverkuil@xs4all.nl> a écrit :
>>>
>>> On 7/2/19 5:52 PM, Hugues Fruchet wrote:
>>>> Add support of several sub-devices within pipeline instead
>>>> of a single one.
>>>> This allows to support a CSI-2 camera sensor connected
>>>> through a CSI-2 to parallel bridge.
>>>>
>>>> Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
>>>> ---
>>>>   drivers/media/platform/stm32/stm32-dcmi.c | 204 +++++++++++++++++++++++++++---
>>>>   1 file changed, 186 insertions(+), 18 deletions(-)
>>>>
>>>> diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
>>>> index 6f37617..6921e6b 100644
>>>> --- a/drivers/media/platform/stm32/stm32-dcmi.c
>>>> +++ b/drivers/media/platform/stm32/stm32-dcmi.c
>>>> @@ -172,6 +172,7 @@ struct stm32_dcmi {
>>>>
>>>>        struct media_device             mdev;
>>>>        struct media_pad                vid_cap_pad;
>>>> +     struct media_pipeline           pipeline;
>>>>   };
>>>>
>>>>   static inline struct stm32_dcmi *notifier_to_dcmi(struct v4l2_async_notifier *n)
>>>> @@ -583,6 +584,131 @@ static void dcmi_buf_queue(struct vb2_buffer *vb)
>>>>        spin_unlock_irq(&dcmi->irqlock);
>>>>   }
>>>>
>>>> +static struct media_entity *dcmi_find_source(struct stm32_dcmi *dcmi)
>>>> +{
>>>> +     struct media_entity *entity = &dcmi->vdev->entity;
>>>> +     struct media_pad *pad;
>>>> +
>>>> +     /* Walk searching for entity having no sink */
>>>> +     while (1) {
>>>> +             pad = &entity->pads[0];
>>>> +             if (!(pad->flags & MEDIA_PAD_FL_SINK))
>>>> +                     break;
>>>> +
>>>> +             pad = media_entity_remote_pad(pad);
>>>> +             if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
>>>> +                     break;
>>>> +
>>>> +             entity = pad->entity;
>>>> +     }
>>>> +
>>>> +     return entity;
>>>> +}
>>>> +
>>>> +static int dcmi_pipeline_s_fmt(struct stm32_dcmi *dcmi,
>>>> +                            struct v4l2_subdev_pad_config *pad_cfg,
>>>> +                            struct v4l2_subdev_format *format)
>>>> +{
>>>> +     struct media_entity *entity = &dcmi->entity.source->entity;
>>>> +     struct v4l2_subdev *subdev;
>>>> +     struct media_pad *sink_pad = NULL;
>>>> +     struct media_pad *src_pad = NULL;
>>>> +     struct media_pad *pad = NULL;
>>>> +     struct v4l2_subdev_format fmt = *format;
>>>> +     bool found = false;
>>>> +     int ret;
>>>> +
>>>> +     /*
>>>> +      * Starting from sensor subdevice, walk within
>>>> +      * pipeline and set format on each subdevice
>>>> +      */
>>>> +     while (1) {
>>>> +             unsigned int i;
>>>> +
>>>> +             /* Search if current entity has a source pad */
>>>> +             for (i = 0; i < entity->num_pads; i++) {
>>>> +                     pad = &entity->pads[i];
>>>> +                     if (pad->flags & MEDIA_PAD_FL_SOURCE) {
>>>> +                             src_pad = pad;
>>>> +                             found = true;
>>>> +                             break;
>>>> +                     }
>>>> +             }
>>>> +             if (!found)
>>>> +                     break;
>>>> +
>>>> +             subdev = media_entity_to_v4l2_subdev(entity);
>>>> +
>>>> +             /* Propagate format on sink pad if any, otherwise source pad */
>>>> +             if (sink_pad)
>>>> +                     pad = sink_pad;
>>>> +
>>>> +             dev_dbg(dcmi->dev, "%s[%d] pad format set to 0x%x %ux%u\n",
>>>> +                     subdev->name, pad->index, format->format.code,
>>>> +                     format->format.width, format->format.height);
>>>> +
>>>> +             fmt.pad = pad->index;
>>>> +             ret = v4l2_subdev_call(subdev, pad, set_fmt, pad_cfg, &fmt);
>>>> +             if (ret < 0)
>>>> +                     return ret;
>>>> +
>>>> +             /* Walk to next entity */
>>>> +             sink_pad = media_entity_remote_pad(src_pad);
>>>> +             if (!sink_pad || !is_media_entity_v4l2_subdev(sink_pad->entity))
>>>> +                     break;
>>>> +
>>>> +             entity = sink_pad->entity;
>>>> +     }
>>>> +     *format = fmt;
>>>> +
>>>> +     return 0;
>>>> +}
>>>> +
>>>> +static int dcmi_pipeline_s_stream(struct stm32_dcmi *dcmi, int state)
>>>> +{
>>>> +     struct media_entity *entity = &dcmi->vdev->entity;
>>>> +     struct v4l2_subdev *subdev;
>>>> +     struct media_pad *pad;
>>>> +     int ret;
>>>> +
>>>> +     /* Start/stop all entities within pipeline */
>>>> +     while (1) {
>>>> +             pad = &entity->pads[0];
>>>> +             if (!(pad->flags & MEDIA_PAD_FL_SINK))
>>>> +                     break;
>>>> +
>>>> +             pad = media_entity_remote_pad(pad);
>>>> +             if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
>>>> +                     break;
>>>> +
>>>> +             entity = pad->entity;
>>>> +             subdev = media_entity_to_v4l2_subdev(entity);
>>>> +
>>>> +             ret = v4l2_subdev_call(subdev, video, s_stream, state);
>>>> +             if (ret < 0 && ret != -ENOIOCTLCMD) {
>>>> +                     dev_err(dcmi->dev, "%s: %s failed to %s streaming (%d)\n",
>>>> +                             __func__, subdev->name,
>>>> +                             state ? "start" : "stop", ret);
>>>> +                     return ret;
>>>> +             }
>>>> +
>>>> +             dev_dbg(dcmi->dev, "%s is %s\n",
>>>> +                     subdev->name, state ? "started" : "stopped");
>>>> +     }
>>>> +
>>>> +     return 0;
>>>> +}
>>>> +
>>>> +static int dcmi_pipeline_start(struct stm32_dcmi *dcmi)
>>>> +{
>>>> +     return dcmi_pipeline_s_stream(dcmi, 1);
>>>> +}
>>>> +
>>>> +static void dcmi_pipeline_stop(struct stm32_dcmi *dcmi)
>>>> +{
>>>> +     dcmi_pipeline_s_stream(dcmi, 0);
>>>> +}
>>>> +
>>>>   static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>>   {
>>>>        struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
>>>> @@ -597,14 +723,17 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>>                goto err_release_buffers;
>>>>        }
>>>>
>>>> -     /* Enable stream on the sub device */
>>>> -     ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 1);
>>>> -     if (ret && ret != -ENOIOCTLCMD) {
>>>> -             dev_err(dcmi->dev, "%s: Failed to start streaming, subdev streamon error",
>>>> -                     __func__);
>>>> +     ret = media_pipeline_start(&dcmi->vdev->entity, &dcmi->pipeline);
>>>> +     if (ret < 0) {
>>>> +             dev_err(dcmi->dev, "%s: Failed to start streaming, media pipeline start error (%d)\n",
>>>> +                     __func__, ret);
>>>>                goto err_pm_put;
>>>>        }
>>>>
>>>> +     ret = dcmi_pipeline_start(dcmi);
>>>> +     if (ret)
>>>> +             goto err_media_pipeline_stop;
>>>> +
>>>>        spin_lock_irq(&dcmi->irqlock);
>>>>
>>>>        /* Set bus width */
>>>> @@ -676,7 +805,7 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>>        if (ret) {
>>>>                dev_err(dcmi->dev, "%s: Start streaming failed, cannot start capture\n",
>>>>                        __func__);
>>>> -             goto err_subdev_streamoff;
>>>> +             goto err_pipeline_stop;
>>>>        }
>>>>
>>>>        /* Enable interruptions */
>>>> @@ -687,8 +816,11 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>>>
>>>>        return 0;
>>>>
>>>> -err_subdev_streamoff:
>>>> -     v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
>>>> +err_pipeline_stop:
>>>> +     dcmi_pipeline_stop(dcmi);
>>>> +
>>>> +err_media_pipeline_stop:
>>>> +     media_pipeline_stop(&dcmi->vdev->entity);
>>>>
>>>>   err_pm_put:
>>>>        pm_runtime_put(dcmi->dev);
>>>> @@ -713,13 +845,10 @@ static void dcmi_stop_streaming(struct vb2_queue *vq)
>>>>   {
>>>>        struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
>>>>        struct dcmi_buf *buf, *node;
>>>> -     int ret;
>>>>
>>>> -     /* Disable stream on the sub device */
>>>> -     ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
>>>> -     if (ret && ret != -ENOIOCTLCMD)
>>>> -             dev_err(dcmi->dev, "%s: Failed to stop streaming, subdev streamoff error (%d)\n",
>>>> -                     __func__, ret);
>>>> +     dcmi_pipeline_stop(dcmi);
>>>> +
>>>> +     media_pipeline_stop(&dcmi->vdev->entity);
>>>>
>>>>        spin_lock_irq(&dcmi->irqlock);
>>>>
>>>> @@ -937,8 +1066,7 @@ static int dcmi_set_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f)
>>>>        mf->width = sd_framesize.width;
>>>>        mf->height = sd_framesize.height;
>>>>
>>>> -     ret = v4l2_subdev_call(dcmi->entity.source, pad,
>>>> -                            set_fmt, NULL, &format);
>>>> +     ret = dcmi_pipeline_s_fmt(dcmi, NULL, &format);
>>>>        if (ret < 0)
>>>>                return ret;
>>>>
>>>> @@ -1529,7 +1657,20 @@ static int dcmi_graph_notify_complete(struct v4l2_async_notifier *notifier)
>>>>        struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
>>>>        int ret;
>>>>
>>>> +     /*
>>>> +      * Now that the graph is complete,
>>>> +      * we search for the source subdevice
>>>> +      * in order to expose it through V4L2 interface
>>>> +      */
>>>> +     dcmi->entity.source =
>>>> +             media_entity_to_v4l2_subdev(dcmi_find_source(dcmi));
>>>> +     if (!dcmi->entity.source) {
>>>> +             dev_err(dcmi->dev, "Source subdevice not found\n");
>>>> +             return -ENODEV;
>>>> +     }
>>>> +
>>>>        dcmi->vdev->ctrl_handler = dcmi->entity.source->ctrl_handler;
>>>> +
>>>>        ret = dcmi_formats_init(dcmi);
>>>>        if (ret) {
>>>>                dev_err(dcmi->dev, "No supported mediabus format found\n");
>>>> @@ -1574,12 +1715,30 @@ static int dcmi_graph_notify_bound(struct v4l2_async_notifier *notifier,
>>>>                                   struct v4l2_async_subdev *asd)
>>>>   {
>>>>        struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
>>>> +     unsigned int ret;
>>>> +     int src_pad;
>>>>
>>>>        dev_dbg(dcmi->dev, "Subdev %s bound\n", subdev->name);
>>>>
>>>> -     dcmi->entity.source = subdev;
>>>> +     /*
>>>> +      * Link this sub-device to DCMI, it could be
>>>> +      * a parallel camera sensor or a bridge
>>>> +      */
>>>> +     src_pad = media_entity_get_fwnode_pad(&subdev->entity,
>>>> +                                           subdev->fwnode,
>>>> +                                           MEDIA_PAD_FL_SOURCE);
>>>> +
>>>> +     ret = media_create_pad_link(&subdev->entity, src_pad,
>>>> +                                 &dcmi->vdev->entity, 0,
>>>> +                                 MEDIA_LNK_FL_IMMUTABLE |
>>>> +                                 MEDIA_LNK_FL_ENABLED);
>>>> +     if (ret)
>>>> +             dev_err(dcmi->dev, "Failed to create media pad link with subdev %s\n",
>>>> +                     subdev->name);
>>>> +     else
>>>> +             dev_dbg(dcmi->dev, "DCMI is now linked to %s\n", subdev->name);
>>>>
>>>> -     return 0;
>>>> +     return ret;
>>>>   }
>>>>
>>>>   static const struct v4l2_async_notifier_operations dcmi_graph_notify_ops = {
>>>> @@ -1639,6 +1798,15 @@ static int dcmi_graph_init(struct stm32_dcmi *dcmi)
>>>>                return ret;
>>>>        }
>>>>
>>>> +     /* Register all the subdev nodes */
>>>> +     ret = v4l2_device_register_subdev_nodes(&dcmi->v4l2_dev);
>>>
>>> This shouldn't be needed. Only MC-centric drivers (i.e. where the pipeline
>>> has to be configured by userspace) need to do this.
>>
>> Hi Hans,
>> I think this point has been discussed in this thread
>> https://www.spinics.net/lists/linux-media/msg153417.html
>>
>> In short : since the hardware only offer one possible path we don't expose
>> the configuration to userland and let DCMI driver configure the
>> subdevice (like bridge).
> 
> Yes, and I agree completely. But why then do you register v4l-subdevX devices?
> That's not needed for this driver.
> 
> Regards,
> 
> 	Hans
> 
>>
>> Benjamin
>>
>>>
>>> Otherwise this patch looks good.
>>>
>>> Regards,
>>>
>>>          Hans
>>>
>>>> +     if (ret) {
>>>> +             dev_err(dcmi->dev, "Failed to register subdev nodes\n");
>>>> +             v4l2_async_notifier_unregister(&dcmi->notifier);
>>>> +             of_node_put(dcmi->entity.remote_node);
>>>> +             return ret;
>>>> +     }
>>>> +
>>>>        return 0;
>>>>   }
>>>>
>>>>
>>>
> 

Best regards,
Hugues.
diff mbox series

Patch

diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
index 6f37617..6921e6b 100644
--- a/drivers/media/platform/stm32/stm32-dcmi.c
+++ b/drivers/media/platform/stm32/stm32-dcmi.c
@@ -172,6 +172,7 @@  struct stm32_dcmi {
 
 	struct media_device		mdev;
 	struct media_pad		vid_cap_pad;
+	struct media_pipeline		pipeline;
 };
 
 static inline struct stm32_dcmi *notifier_to_dcmi(struct v4l2_async_notifier *n)
@@ -583,6 +584,131 @@  static void dcmi_buf_queue(struct vb2_buffer *vb)
 	spin_unlock_irq(&dcmi->irqlock);
 }
 
+static struct media_entity *dcmi_find_source(struct stm32_dcmi *dcmi)
+{
+	struct media_entity *entity = &dcmi->vdev->entity;
+	struct media_pad *pad;
+
+	/* Walk searching for entity having no sink */
+	while (1) {
+		pad = &entity->pads[0];
+		if (!(pad->flags & MEDIA_PAD_FL_SINK))
+			break;
+
+		pad = media_entity_remote_pad(pad);
+		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
+			break;
+
+		entity = pad->entity;
+	}
+
+	return entity;
+}
+
+static int dcmi_pipeline_s_fmt(struct stm32_dcmi *dcmi,
+			       struct v4l2_subdev_pad_config *pad_cfg,
+			       struct v4l2_subdev_format *format)
+{
+	struct media_entity *entity = &dcmi->entity.source->entity;
+	struct v4l2_subdev *subdev;
+	struct media_pad *sink_pad = NULL;
+	struct media_pad *src_pad = NULL;
+	struct media_pad *pad = NULL;
+	struct v4l2_subdev_format fmt = *format;
+	bool found = false;
+	int ret;
+
+	/*
+	 * Starting from sensor subdevice, walk within
+	 * pipeline and set format on each subdevice
+	 */
+	while (1) {
+		unsigned int i;
+
+		/* Search if current entity has a source pad */
+		for (i = 0; i < entity->num_pads; i++) {
+			pad = &entity->pads[i];
+			if (pad->flags & MEDIA_PAD_FL_SOURCE) {
+				src_pad = pad;
+				found = true;
+				break;
+			}
+		}
+		if (!found)
+			break;
+
+		subdev = media_entity_to_v4l2_subdev(entity);
+
+		/* Propagate format on sink pad if any, otherwise source pad */
+		if (sink_pad)
+			pad = sink_pad;
+
+		dev_dbg(dcmi->dev, "%s[%d] pad format set to 0x%x %ux%u\n",
+			subdev->name, pad->index, format->format.code,
+			format->format.width, format->format.height);
+
+		fmt.pad = pad->index;
+		ret = v4l2_subdev_call(subdev, pad, set_fmt, pad_cfg, &fmt);
+		if (ret < 0)
+			return ret;
+
+		/* Walk to next entity */
+		sink_pad = media_entity_remote_pad(src_pad);
+		if (!sink_pad || !is_media_entity_v4l2_subdev(sink_pad->entity))
+			break;
+
+		entity = sink_pad->entity;
+	}
+	*format = fmt;
+
+	return 0;
+}
+
+static int dcmi_pipeline_s_stream(struct stm32_dcmi *dcmi, int state)
+{
+	struct media_entity *entity = &dcmi->vdev->entity;
+	struct v4l2_subdev *subdev;
+	struct media_pad *pad;
+	int ret;
+
+	/* Start/stop all entities within pipeline */
+	while (1) {
+		pad = &entity->pads[0];
+		if (!(pad->flags & MEDIA_PAD_FL_SINK))
+			break;
+
+		pad = media_entity_remote_pad(pad);
+		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
+			break;
+
+		entity = pad->entity;
+		subdev = media_entity_to_v4l2_subdev(entity);
+
+		ret = v4l2_subdev_call(subdev, video, s_stream, state);
+		if (ret < 0 && ret != -ENOIOCTLCMD) {
+			dev_err(dcmi->dev, "%s: %s failed to %s streaming (%d)\n",
+				__func__, subdev->name,
+				state ? "start" : "stop", ret);
+			return ret;
+		}
+
+		dev_dbg(dcmi->dev, "%s is %s\n",
+			subdev->name, state ? "started" : "stopped");
+	}
+
+	return 0;
+}
+
+static int dcmi_pipeline_start(struct stm32_dcmi *dcmi)
+{
+	return dcmi_pipeline_s_stream(dcmi, 1);
+}
+
+static void dcmi_pipeline_stop(struct stm32_dcmi *dcmi)
+{
+	dcmi_pipeline_s_stream(dcmi, 0);
+}
+
 static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
 {
 	struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
@@ -597,14 +723,17 @@  static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
 		goto err_release_buffers;
 	}
 
-	/* Enable stream on the sub device */
-	ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 1);
-	if (ret && ret != -ENOIOCTLCMD) {
-		dev_err(dcmi->dev, "%s: Failed to start streaming, subdev streamon error",
-			__func__);
+	ret = media_pipeline_start(&dcmi->vdev->entity, &dcmi->pipeline);
+	if (ret < 0) {
+		dev_err(dcmi->dev, "%s: Failed to start streaming, media pipeline start error (%d)\n",
+			__func__, ret);
 		goto err_pm_put;
 	}
 
+	ret = dcmi_pipeline_start(dcmi);
+	if (ret)
+		goto err_media_pipeline_stop;
+
 	spin_lock_irq(&dcmi->irqlock);
 
 	/* Set bus width */
@@ -676,7 +805,7 @@  static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
 	if (ret) {
 		dev_err(dcmi->dev, "%s: Start streaming failed, cannot start capture\n",
 			__func__);
-		goto err_subdev_streamoff;
+		goto err_pipeline_stop;
 	}
 
 	/* Enable interruptions */
@@ -687,8 +816,11 @@  static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
 
 	return 0;
 
-err_subdev_streamoff:
-	v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
+err_pipeline_stop:
+	dcmi_pipeline_stop(dcmi);
+
+err_media_pipeline_stop:
+	media_pipeline_stop(&dcmi->vdev->entity);
 
 err_pm_put:
 	pm_runtime_put(dcmi->dev);
@@ -713,13 +845,10 @@  static void dcmi_stop_streaming(struct vb2_queue *vq)
 {
 	struct stm32_dcmi *dcmi = vb2_get_drv_priv(vq);
 	struct dcmi_buf *buf, *node;
-	int ret;
 
-	/* Disable stream on the sub device */
-	ret = v4l2_subdev_call(dcmi->entity.source, video, s_stream, 0);
-	if (ret && ret != -ENOIOCTLCMD)
-		dev_err(dcmi->dev, "%s: Failed to stop streaming, subdev streamoff error (%d)\n",
-			__func__, ret);
+	dcmi_pipeline_stop(dcmi);
+
+	media_pipeline_stop(&dcmi->vdev->entity);
 
 	spin_lock_irq(&dcmi->irqlock);
 
@@ -937,8 +1066,7 @@  static int dcmi_set_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f)
 	mf->width = sd_framesize.width;
 	mf->height = sd_framesize.height;
 
-	ret = v4l2_subdev_call(dcmi->entity.source, pad,
-			       set_fmt, NULL, &format);
+	ret = dcmi_pipeline_s_fmt(dcmi, NULL, &format);
 	if (ret < 0)
 		return ret;
 
@@ -1529,7 +1657,20 @@  static int dcmi_graph_notify_complete(struct v4l2_async_notifier *notifier)
 	struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
 	int ret;
 
+	/*
+	 * Now that the graph is complete,
+	 * we search for the source subdevice
+	 * in order to expose it through V4L2 interface
+	 */
+	dcmi->entity.source =
+		media_entity_to_v4l2_subdev(dcmi_find_source(dcmi));
+	if (!dcmi->entity.source) {
+		dev_err(dcmi->dev, "Source subdevice not found\n");
+		return -ENODEV;
+	}
+
 	dcmi->vdev->ctrl_handler = dcmi->entity.source->ctrl_handler;
+
 	ret = dcmi_formats_init(dcmi);
 	if (ret) {
 		dev_err(dcmi->dev, "No supported mediabus format found\n");
@@ -1574,12 +1715,30 @@  static int dcmi_graph_notify_bound(struct v4l2_async_notifier *notifier,
 				   struct v4l2_async_subdev *asd)
 {
 	struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
+	unsigned int ret;
+	int src_pad;
 
 	dev_dbg(dcmi->dev, "Subdev %s bound\n", subdev->name);
 
-	dcmi->entity.source = subdev;
+	/*
+	 * Link this sub-device to DCMI, it could be
+	 * a parallel camera sensor or a bridge
+	 */
+	src_pad = media_entity_get_fwnode_pad(&subdev->entity,
+					      subdev->fwnode,
+					      MEDIA_PAD_FL_SOURCE);
+
+	ret = media_create_pad_link(&subdev->entity, src_pad,
+				    &dcmi->vdev->entity, 0,
+				    MEDIA_LNK_FL_IMMUTABLE |
+				    MEDIA_LNK_FL_ENABLED);
+	if (ret)
+		dev_err(dcmi->dev, "Failed to create media pad link with subdev %s\n",
+			subdev->name);
+	else
+		dev_dbg(dcmi->dev, "DCMI is now linked to %s\n", subdev->name);
 
-	return 0;
+	return ret;
 }
 
 static const struct v4l2_async_notifier_operations dcmi_graph_notify_ops = {
@@ -1639,6 +1798,15 @@  static int dcmi_graph_init(struct stm32_dcmi *dcmi)
 		return ret;
 	}
 
+	/* Register all the subdev nodes */
+	ret = v4l2_device_register_subdev_nodes(&dcmi->v4l2_dev);
+	if (ret) {
+		dev_err(dcmi->dev, "Failed to register subdev nodes\n");
+		v4l2_async_notifier_unregister(&dcmi->notifier);
+		of_node_put(dcmi->entity.remote_node);
+		return ret;
+	}
+
 	return 0;
 }