diff mbox series

[v2,3/3] media: stm32-dcmi: add support of several sub-devices

Message ID 1560242912-17138-4-git-send-email-hugues.fruchet@st.com (mailing list archive)
State New, archived
Headers show
Series DCMI bridge support | expand

Commit Message

Hugues FRUCHET June 11, 2019, 8:48 a.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 | 207 +++++++++++++++++++++++++++---
 1 file changed, 189 insertions(+), 18 deletions(-)

Comments

Sakari Ailus June 20, 2019, 3:54 p.m. UTC | #1
Hi Hugues,

Thank you for the update.

On Tue, Jun 11, 2019 at 10:48:32AM +0200, 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 | 207 +++++++++++++++++++++++++++---
>  1 file changed, 189 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
> index 3a69783..144912f 100644
> --- a/drivers/media/platform/stm32/stm32-dcmi.c
> +++ b/drivers/media/platform/stm32/stm32-dcmi.c
> @@ -173,6 +173,7 @@ 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)
> @@ -584,6 +585,135 @@ static void dcmi_buf_queue(struct vb2_buffer *vb)
>  	spin_unlock_irq(&dcmi->irqlock);
>  }
>  
> +static struct media_entity *dcmi_find_sensor(struct stm32_dcmi *dcmi)

You generally should be only concerned with the next entity connected to the
one you're in control of, not the rest of the pipeline.

> +{
> +	struct media_entity *entity = &dcmi->vdev->entity;
> +	struct v4l2_subdev *subdev;
> +	struct media_pad *pad;
> +
> +	/* Walk searching for entity having no sink */
> +	while (1) {
> +		pad = &entity->pads[0];
> +
> +		subdev = media_entity_to_v4l2_subdev(entity);
> +
> +		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->sensor->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);

Generally speaking, on MC-centric devices, the user space needs to
configure the pipeline. The driver's responsibility is to validate it
(through the link_validate media entity and subdev pad ops). I.e. set_fmt
is only used through the subdev nodes.

> +		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);

Please only call this on the next upstream sub-device. See e.g. the
ipu3-cio2 or omap3isp driver for an example.

> +		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);
> @@ -598,14 +728,17 @@ 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->sensor, 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 */
> @@ -677,7 +810,7 @@ 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 */
> @@ -688,8 +821,11 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>  
>  	return 0;
>  
> -err_subdev_streamoff:
> -	v4l2_subdev_call(dcmi->sensor, 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);
> @@ -714,13 +850,10 @@ 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->sensor, 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);
>  
> @@ -938,8 +1071,7 @@ 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->sensor, pad,
> -			       set_fmt, NULL, &format);
> +	ret = dcmi_pipeline_s_fmt(dcmi, NULL, &format);
>  	if (ret < 0)
>  		return ret;
>  
> @@ -1530,7 +1662,19 @@ 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 camera sensor subdevice
> +	 * in order to expose it through V4L2 interface
> +	 */
> +	dcmi->sensor = media_entity_to_v4l2_subdev(dcmi_find_sensor(dcmi));
> +	if (!dcmi->sensor) {
> +		dev_err(dcmi->dev, "No camera sensor subdevice found\n");
> +		return -ENODEV;
> +	}
> +
>  	dcmi->vdev->ctrl_handler = dcmi->sensor->ctrl_handler;
> +
>  	ret = dcmi_formats_init(dcmi);
>  	if (ret) {
>  		dev_err(dcmi->dev, "No supported mediabus format found\n");
> @@ -1574,12 +1718,30 @@ 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->sensor = 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 +1801,15 @@ 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.node);
> +		return ret;
> +	}
> +
>  	return 0;
>  }
>
Hugues FRUCHET July 2, 2019, 3:26 p.m. UTC | #2
Hi Sakari,

On 6/20/19 5:54 PM, Sakari Ailus wrote:
> Hi Hugues,
> 
> Thank you for the update.
> 
> On Tue, Jun 11, 2019 at 10:48:32AM +0200, 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 | 207 +++++++++++++++++++++++++++---
>>   1 file changed, 189 insertions(+), 18 deletions(-)
>>
>> diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
>> index 3a69783..144912f 100644
>> --- a/drivers/media/platform/stm32/stm32-dcmi.c
>> +++ b/drivers/media/platform/stm32/stm32-dcmi.c
>> @@ -173,6 +173,7 @@ 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)
>> @@ -584,6 +585,135 @@ static void dcmi_buf_queue(struct vb2_buffer *vb)
>>   	spin_unlock_irq(&dcmi->irqlock);
>>   }
>>   
>> +static struct media_entity *dcmi_find_sensor(struct stm32_dcmi *dcmi)
> 
> You generally should be only concerned with the next entity connected to the
> one you're in control of, not the rest of the pipeline.

This was discussed with Laurent here:
https://www.spinics.net/lists/linux-media/msg153417.html
and it's OK because DCMI is a video node and we are not
exposing media controller interface to userspace.

> 
>> +{
>> +	struct media_entity *entity = &dcmi->vdev->entity;
>> +	struct v4l2_subdev *subdev;
>> +	struct media_pad *pad;
>> +
>> +	/* Walk searching for entity having no sink */
>> +	while (1) {
>> +		pad = &entity->pads[0];
>> +
>> +		subdev = media_entity_to_v4l2_subdev(entity);
>> +
>> +		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->sensor->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);
> 
> Generally speaking, on MC-centric devices, the user space needs to
> configure the pipeline. The driver's responsibility is to validate it
> (through the link_validate media entity and subdev pad ops). I.e. set_fmt
> is only used through the subdev nodes.
> 
ditto

>> +		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);
> 
> Please only call this on the next upstream sub-device. See e.g. the
> ipu3-cio2 or omap3isp driver for an example.
> 
ditto

>> +		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);
>> @@ -598,14 +728,17 @@ 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->sensor, 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 */
>> @@ -677,7 +810,7 @@ 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 */
>> @@ -688,8 +821,11 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>>   
>>   	return 0;
>>   
>> -err_subdev_streamoff:
>> -	v4l2_subdev_call(dcmi->sensor, 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);
>> @@ -714,13 +850,10 @@ 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->sensor, 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);
>>   
>> @@ -938,8 +1071,7 @@ 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->sensor, pad,
>> -			       set_fmt, NULL, &format);
>> +	ret = dcmi_pipeline_s_fmt(dcmi, NULL, &format);
>>   	if (ret < 0)
>>   		return ret;
>>   
>> @@ -1530,7 +1662,19 @@ 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 camera sensor subdevice
>> +	 * in order to expose it through V4L2 interface
>> +	 */
>> +	dcmi->sensor = media_entity_to_v4l2_subdev(dcmi_find_sensor(dcmi));
>> +	if (!dcmi->sensor) {
>> +		dev_err(dcmi->dev, "No camera sensor subdevice found\n");
>> +		return -ENODEV;
>> +	}
>> +
>>   	dcmi->vdev->ctrl_handler = dcmi->sensor->ctrl_handler;
>> +
>>   	ret = dcmi_formats_init(dcmi);
>>   	if (ret) {
>>   		dev_err(dcmi->dev, "No supported mediabus format found\n");
>> @@ -1574,12 +1718,30 @@ 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->sensor = 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 +1801,15 @@ 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.node);
>> +		return ret;
>> +	}
>> +
>>   	return 0;
>>   }
>>   
> 

BR,
Hugues.
diff mbox series

Patch

diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
index 3a69783..144912f 100644
--- a/drivers/media/platform/stm32/stm32-dcmi.c
+++ b/drivers/media/platform/stm32/stm32-dcmi.c
@@ -173,6 +173,7 @@  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)
@@ -584,6 +585,135 @@  static void dcmi_buf_queue(struct vb2_buffer *vb)
 	spin_unlock_irq(&dcmi->irqlock);
 }
 
+static struct media_entity *dcmi_find_sensor(struct stm32_dcmi *dcmi)
+{
+	struct media_entity *entity = &dcmi->vdev->entity;
+	struct v4l2_subdev *subdev;
+	struct media_pad *pad;
+
+	/* Walk searching for entity having no sink */
+	while (1) {
+		pad = &entity->pads[0];
+
+		subdev = media_entity_to_v4l2_subdev(entity);
+
+		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->sensor->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);
@@ -598,14 +728,17 @@  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->sensor, 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 */
@@ -677,7 +810,7 @@  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 */
@@ -688,8 +821,11 @@  static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
 
 	return 0;
 
-err_subdev_streamoff:
-	v4l2_subdev_call(dcmi->sensor, 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);
@@ -714,13 +850,10 @@  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->sensor, 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);
 
@@ -938,8 +1071,7 @@  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->sensor, pad,
-			       set_fmt, NULL, &format);
+	ret = dcmi_pipeline_s_fmt(dcmi, NULL, &format);
 	if (ret < 0)
 		return ret;
 
@@ -1530,7 +1662,19 @@  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 camera sensor subdevice
+	 * in order to expose it through V4L2 interface
+	 */
+	dcmi->sensor = media_entity_to_v4l2_subdev(dcmi_find_sensor(dcmi));
+	if (!dcmi->sensor) {
+		dev_err(dcmi->dev, "No camera sensor subdevice found\n");
+		return -ENODEV;
+	}
+
 	dcmi->vdev->ctrl_handler = dcmi->sensor->ctrl_handler;
+
 	ret = dcmi_formats_init(dcmi);
 	if (ret) {
 		dev_err(dcmi->dev, "No supported mediabus format found\n");
@@ -1574,12 +1718,30 @@  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->sensor = 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 +1801,15 @@  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.node);
+		return ret;
+	}
+
 	return 0;
 }