[PATCH] media: Accept non-subdev sinks in v4l2_create_fwnode_links_to_pad()

[PATCH] media: Accept non-subdev sinks in v4l2_create_fwnode_links_to_pad()

[Laurent Pinchart]

The v4l2_create_fwnode_links_to_pad() helper requires the sink pad
passed to it to belong to a subdev. This requirement can be lifted
easily. Make the function usable for non-subdev sinks, which allows
using it with video_device sinks.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/media/v4l2-core/v4l2-mc.c | 15 ++++++---------
 include/media/v4l2-mc.h           |  8 ++++----
 2 files changed, 10 insertions(+), 13 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-mc.c b/drivers/media/v4l2-core/v4l2-mc.c
index b01474717dca..bf0c18100664 100644
--- a/drivers/media/v4l2-core/v4l2-mc.c
+++ b/drivers/media/v4l2-core/v4l2-mc.c
@@ -313,14 +313,11 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
 				    struct media_pad *sink, u32 flags)
 {
 	struct fwnode_handle *endpoint;
-	struct v4l2_subdev *sink_sd;
 
 	if (!(sink->flags & MEDIA_PAD_FL_SINK) ||
 	    !is_media_entity_v4l2_subdev(sink->entity))
 		return -EINVAL;
 
-	sink_sd = media_entity_to_v4l2_subdev(sink->entity);
-
 	fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {
 		struct fwnode_handle *remote_ep;
 		int src_idx, sink_idx, ret;
@@ -340,7 +337,7 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
 		 * ask the sink to verify it owns the remote endpoint,
 		 * and translate to a sink pad.
 		 */
-		sink_idx = media_entity_get_fwnode_pad(&sink_sd->entity,
+		sink_idx = media_entity_get_fwnode_pad(sink->entity,
 						       remote_ep,
 						       MEDIA_PAD_FL_SINK);
 		fwnode_handle_put(remote_ep);
@@ -362,17 +359,17 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
 		if (media_entity_find_link(src, sink))
 			continue;
 
-		dev_dbg(sink_sd->dev, "creating link %s:%d -> %s:%d\n",
+		dev_dbg(src_sd->dev, "creating link %s:%d -> %s:%d\n",
 			src_sd->entity.name, src_idx,
-			sink_sd->entity.name, sink_idx);
+			sink->entity->name, sink_idx);
 
 		ret = media_create_pad_link(&src_sd->entity, src_idx,
-					    &sink_sd->entity, sink_idx, flags);
+					    sink->entity, sink_idx, flags);
 		if (ret) {
-			dev_err(sink_sd->dev,
+			dev_err(src_sd->dev,
 				"link %s:%d -> %s:%d failed with %d\n",
 				src_sd->entity.name, src_idx,
-				sink_sd->entity.name, sink_idx, ret);
+				sink->entity->name, sink_idx, ret);
 
 			fwnode_handle_put(endpoint);
 			return ret;
diff --git a/include/media/v4l2-mc.h b/include/media/v4l2-mc.h
index c181685923d5..b39586dfba35 100644
--- a/include/media/v4l2-mc.h
+++ b/include/media/v4l2-mc.h
@@ -87,17 +87,17 @@ int v4l_vb2q_enable_media_source(struct vb2_queue *q);
 
 /**
  * v4l2_create_fwnode_links_to_pad - Create fwnode-based links from a
- *                                   source subdev to a sink subdev pad.
+ *                                   source subdev to a sink pad.
  *
  * @src_sd: pointer to a source subdev
- * @sink:  pointer to a subdev sink pad
+ * @sink:  pointer to a sink pad
  * @flags: the link flags
  *
  * This function searches for fwnode endpoint connections from a source
  * subdevice to a single sink pad, and if suitable connections are found,
  * translates them into media links to that pad. The function can be
- * called by the sink subdevice, in its v4l2-async notifier subdev bound
- * callback, to create links from a bound source subdevice.
+ * called by the sink, in its v4l2-async notifier bound callback, to create
+ * links from a bound source subdevice.
  *
  * The @flags argument specifies the link flags. The caller shall ensure that
  * the flags are valid regardless of the number of links that may be created.
-- 
Regards,

Laurent Pinchart

Re: [PATCH] media: Accept non-subdev sinks in v4l2_create_fwnode_links_to_pad()

[Vaishnav Achath]

Hi Laurent,

Thank you for the patch, sorry for the delay in response,

On 24/03/23 16:05, Laurent Pinchart wrote:
> The v4l2_create_fwnode_links_to_pad() helper requires the sink pad
> passed to it to belong to a subdev. This requirement can be lifted
> easily. Make the function usable for non-subdev sinks, which allows
> using it with video_device sinks.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
>  drivers/media/v4l2-core/v4l2-mc.c | 15 ++++++---------
>  include/media/v4l2-mc.h           |  8 ++++----
>  2 files changed, 10 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-mc.c b/drivers/media/v4l2-core/v4l2-mc.c
> index b01474717dca..bf0c18100664 100644
> --- a/drivers/media/v4l2-core/v4l2-mc.c
> +++ b/drivers/media/v4l2-core/v4l2-mc.c
> @@ -313,14 +313,11 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
>  				    struct media_pad *sink, u32 flags)
>  {
>  	struct fwnode_handle *endpoint;
> -	struct v4l2_subdev *sink_sd;
>  
>  	if (!(sink->flags & MEDIA_PAD_FL_SINK) ||
>  	    !is_media_entity_v4l2_subdev(sink->entity))

should we drop the second check here also, i.e

!is_media_entity_v4l2_subdev(sink->entity)

to accept non-subdev sinks? is my understanding correct?

Thanks and Regards,
Vaishnav

>  		return -EINVAL;
>  
> -	sink_sd = media_entity_to_v4l2_subdev(sink->entity);
> -
>  	fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {
>  		struct fwnode_handle *remote_ep;
>  		int src_idx, sink_idx, ret;
> @@ -340,7 +337,7 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
>  		 * ask the sink to verify it owns the remote endpoint,
>  		 * and translate to a sink pad.
>  		 */
> -		sink_idx = media_entity_get_fwnode_pad(&sink_sd->entity,
> +		sink_idx = media_entity_get_fwnode_pad(sink->entity,
>  						       remote_ep,
>  						       MEDIA_PAD_FL_SINK);
>  		fwnode_handle_put(remote_ep);
> @@ -362,17 +359,17 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
>  		if (media_entity_find_link(src, sink))
>  			continue;
>  
> -		dev_dbg(sink_sd->dev, "creating link %s:%d -> %s:%d\n",
> +		dev_dbg(src_sd->dev, "creating link %s:%d -> %s:%d\n",
>  			src_sd->entity.name, src_idx,
> -			sink_sd->entity.name, sink_idx);
> +			sink->entity->name, sink_idx);
>  
>  		ret = media_create_pad_link(&src_sd->entity, src_idx,
> -					    &sink_sd->entity, sink_idx, flags);
> +					    sink->entity, sink_idx, flags);
>  		if (ret) {
> -			dev_err(sink_sd->dev,
> +			dev_err(src_sd->dev,
>  				"link %s:%d -> %s:%d failed with %d\n",
>  				src_sd->entity.name, src_idx,
> -				sink_sd->entity.name, sink_idx, ret);
> +				sink->entity->name, sink_idx, ret);
>  
>  			fwnode_handle_put(endpoint);
>  			return ret;
> diff --git a/include/media/v4l2-mc.h b/include/media/v4l2-mc.h
> index c181685923d5..b39586dfba35 100644
> --- a/include/media/v4l2-mc.h
> +++ b/include/media/v4l2-mc.h
> @@ -87,17 +87,17 @@ int v4l_vb2q_enable_media_source(struct vb2_queue *q);
>  
>  /**
>   * v4l2_create_fwnode_links_to_pad - Create fwnode-based links from a
> - *                                   source subdev to a sink subdev pad.
> + *                                   source subdev to a sink pad.
>   *
>   * @src_sd: pointer to a source subdev
> - * @sink:  pointer to a subdev sink pad
> + * @sink:  pointer to a sink pad
>   * @flags: the link flags
>   *
>   * This function searches for fwnode endpoint connections from a source
>   * subdevice to a single sink pad, and if suitable connections are found,
>   * translates them into media links to that pad. The function can be
> - * called by the sink subdevice, in its v4l2-async notifier subdev bound
> - * callback, to create links from a bound source subdevice.
> + * called by the sink, in its v4l2-async notifier bound callback, to create
> + * links from a bound source subdevice.
>   *
>   * The @flags argument specifies the link flags. The caller shall ensure that
>   * the flags are valid regardless of the number of links that may be created.

-- 
Regards,
Vaishnav

Re: [PATCH] media: Accept non-subdev sinks in v4l2_create_fwnode_links_to_pad()

[Laurent Pinchart]

Hi Vaishnav,

On Thu, Apr 13, 2023 at 06:51:23PM +0530, Vaishnav Achath wrote:
> Hi Laurent,
> 
> Thank you for the patch, sorry for the delay in response,
> 
> On 24/03/23 16:05, Laurent Pinchart wrote:
> > The v4l2_create_fwnode_links_to_pad() helper requires the sink pad
> > passed to it to belong to a subdev. This requirement can be lifted
> > easily. Make the function usable for non-subdev sinks, which allows
> > using it with video_device sinks.
> > 
> > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > ---
> >  drivers/media/v4l2-core/v4l2-mc.c | 15 ++++++---------
> >  include/media/v4l2-mc.h           |  8 ++++----
> >  2 files changed, 10 insertions(+), 13 deletions(-)
> > 
> > diff --git a/drivers/media/v4l2-core/v4l2-mc.c b/drivers/media/v4l2-core/v4l2-mc.c
> > index b01474717dca..bf0c18100664 100644
> > --- a/drivers/media/v4l2-core/v4l2-mc.c
> > +++ b/drivers/media/v4l2-core/v4l2-mc.c
> > @@ -313,14 +313,11 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
> >  				    struct media_pad *sink, u32 flags)
> >  {
> >  	struct fwnode_handle *endpoint;
> > -	struct v4l2_subdev *sink_sd;
> >  
> >  	if (!(sink->flags & MEDIA_PAD_FL_SINK) ||
> >  	    !is_media_entity_v4l2_subdev(sink->entity))
> 
> should we drop the second check here also, i.e
> 
> !is_media_entity_v4l2_subdev(sink->entity)
> 
> to accept non-subdev sinks? is my understanding correct?

You're absolutely right. The patch has been merged already I'm afraid.
Would you like to submit a fix, or should I do so ? In the latter case,
can I include a Reported-by tag with your name ?

> >  		return -EINVAL;
> >  
> > -	sink_sd = media_entity_to_v4l2_subdev(sink->entity);
> > -
> >  	fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {
> >  		struct fwnode_handle *remote_ep;
> >  		int src_idx, sink_idx, ret;
> > @@ -340,7 +337,7 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
> >  		 * ask the sink to verify it owns the remote endpoint,
> >  		 * and translate to a sink pad.
> >  		 */
> > -		sink_idx = media_entity_get_fwnode_pad(&sink_sd->entity,
> > +		sink_idx = media_entity_get_fwnode_pad(sink->entity,
> >  						       remote_ep,
> >  						       MEDIA_PAD_FL_SINK);
> >  		fwnode_handle_put(remote_ep);
> > @@ -362,17 +359,17 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
> >  		if (media_entity_find_link(src, sink))
> >  			continue;
> >  
> > -		dev_dbg(sink_sd->dev, "creating link %s:%d -> %s:%d\n",
> > +		dev_dbg(src_sd->dev, "creating link %s:%d -> %s:%d\n",
> >  			src_sd->entity.name, src_idx,
> > -			sink_sd->entity.name, sink_idx);
> > +			sink->entity->name, sink_idx);
> >  
> >  		ret = media_create_pad_link(&src_sd->entity, src_idx,
> > -					    &sink_sd->entity, sink_idx, flags);
> > +					    sink->entity, sink_idx, flags);
> >  		if (ret) {
> > -			dev_err(sink_sd->dev,
> > +			dev_err(src_sd->dev,
> >  				"link %s:%d -> %s:%d failed with %d\n",
> >  				src_sd->entity.name, src_idx,
> > -				sink_sd->entity.name, sink_idx, ret);
> > +				sink->entity->name, sink_idx, ret);
> >  
> >  			fwnode_handle_put(endpoint);
> >  			return ret;
> > diff --git a/include/media/v4l2-mc.h b/include/media/v4l2-mc.h
> > index c181685923d5..b39586dfba35 100644
> > --- a/include/media/v4l2-mc.h
> > +++ b/include/media/v4l2-mc.h
> > @@ -87,17 +87,17 @@ int v4l_vb2q_enable_media_source(struct vb2_queue *q);
> >  
> >  /**
> >   * v4l2_create_fwnode_links_to_pad - Create fwnode-based links from a
> > - *                                   source subdev to a sink subdev pad.
> > + *                                   source subdev to a sink pad.
> >   *
> >   * @src_sd: pointer to a source subdev
> > - * @sink:  pointer to a subdev sink pad
> > + * @sink:  pointer to a sink pad
> >   * @flags: the link flags
> >   *
> >   * This function searches for fwnode endpoint connections from a source
> >   * subdevice to a single sink pad, and if suitable connections are found,
> >   * translates them into media links to that pad. The function can be
> > - * called by the sink subdevice, in its v4l2-async notifier subdev bound
> > - * callback, to create links from a bound source subdevice.
> > + * called by the sink, in its v4l2-async notifier bound callback, to create
> > + * links from a bound source subdevice.
> >   *
> >   * The @flags argument specifies the link flags. The caller shall ensure that
> >   * the flags are valid regardless of the number of links that may be created.

-- 
Regards,

Laurent Pinchart

Re: [PATCH] media: Accept non-subdev sinks in v4l2_create_fwnode_links_to_pad()

[Vaishnav Achath]

Hi Laurent,

On 20/04/23 22:15, Laurent Pinchart wrote:
> Hi Vaishnav,
> 
> On Thu, Apr 13, 2023 at 06:51:23PM +0530, Vaishnav Achath wrote:
>> Hi Laurent,
>>
>> Thank you for the patch, sorry for the delay in response,
>>
>> On 24/03/23 16:05, Laurent Pinchart wrote:
>>> The v4l2_create_fwnode_links_to_pad() helper requires the sink pad
>>> passed to it to belong to a subdev. This requirement can be lifted
>>> easily. Make the function usable for non-subdev sinks, which allows
>>> using it with video_device sinks.
>>>
>>> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
>>> ---
>>>  drivers/media/v4l2-core/v4l2-mc.c | 15 ++++++---------
>>>  include/media/v4l2-mc.h           |  8 ++++----
>>>  2 files changed, 10 insertions(+), 13 deletions(-)
>>>
>>> diff --git a/drivers/media/v4l2-core/v4l2-mc.c b/drivers/media/v4l2-core/v4l2-mc.c
>>> index b01474717dca..bf0c18100664 100644
>>> --- a/drivers/media/v4l2-core/v4l2-mc.c
>>> +++ b/drivers/media/v4l2-core/v4l2-mc.c
>>> @@ -313,14 +313,11 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
>>>  				    struct media_pad *sink, u32 flags)
>>>  {
>>>  	struct fwnode_handle *endpoint;
>>> -	struct v4l2_subdev *sink_sd;
>>>  
>>>  	if (!(sink->flags & MEDIA_PAD_FL_SINK) ||
>>>  	    !is_media_entity_v4l2_subdev(sink->entity))
>>
>> should we drop the second check here also, i.e
>>
>> !is_media_entity_v4l2_subdev(sink->entity)
>>
>> to accept non-subdev sinks? is my understanding correct?
> 
> You're absolutely right. The patch has been merged already I'm afraid.
> Would you like to submit a fix, or should I do so ? In the latter case,
> can I include a Reported-by tag with your name ?
> 

Thank you for confirming, I have send a fix for this as I had tested with the
fix while reworking the j721e-csi2rx series,

https://lore.kernel.org/all/20230421100430.28962-1-vaishnav.a@ti.com/

Thanks and Regards,
Vaishnav

>>>  		return -EINVAL;
>>>  
>>> -	sink_sd = media_entity_to_v4l2_subdev(sink->entity);
>>> -
>>>  	fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {
>>>  		struct fwnode_handle *remote_ep;
>>>  		int src_idx, sink_idx, ret;
>>> @@ -340,7 +337,7 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
>>>  		 * ask the sink to verify it owns the remote endpoint,
>>>  		 * and translate to a sink pad.
>>>  		 */
>>> -		sink_idx = media_entity_get_fwnode_pad(&sink_sd->entity,
>>> +		sink_idx = media_entity_get_fwnode_pad(sink->entity,
>>>  						       remote_ep,
>>>  						       MEDIA_PAD_FL_SINK);
>>>  		fwnode_handle_put(remote_ep);
>>> @@ -362,17 +359,17 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
>>>  		if (media_entity_find_link(src, sink))
>>>  			continue;
>>>  
>>> -		dev_dbg(sink_sd->dev, "creating link %s:%d -> %s:%d\n",
>>> +		dev_dbg(src_sd->dev, "creating link %s:%d -> %s:%d\n",
>>>  			src_sd->entity.name, src_idx,
>>> -			sink_sd->entity.name, sink_idx);
>>> +			sink->entity->name, sink_idx);
>>>  
>>>  		ret = media_create_pad_link(&src_sd->entity, src_idx,
>>> -					    &sink_sd->entity, sink_idx, flags);
>>> +					    sink->entity, sink_idx, flags);
>>>  		if (ret) {
>>> -			dev_err(sink_sd->dev,
>>> +			dev_err(src_sd->dev,
>>>  				"link %s:%d -> %s:%d failed with %d\n",
>>>  				src_sd->entity.name, src_idx,
>>> -				sink_sd->entity.name, sink_idx, ret);
>>> +				sink->entity->name, sink_idx, ret);
>>>  
>>>  			fwnode_handle_put(endpoint);
>>>  			return ret;
>>> diff --git a/include/media/v4l2-mc.h b/include/media/v4l2-mc.h
>>> index c181685923d5..b39586dfba35 100644
>>> --- a/include/media/v4l2-mc.h
>>> +++ b/include/media/v4l2-mc.h
>>> @@ -87,17 +87,17 @@ int v4l_vb2q_enable_media_source(struct vb2_queue *q);
>>>  
>>>  /**
>>>   * v4l2_create_fwnode_links_to_pad - Create fwnode-based links from a
>>> - *                                   source subdev to a sink subdev pad.
>>> + *                                   source subdev to a sink pad.
>>>   *
>>>   * @src_sd: pointer to a source subdev
>>> - * @sink:  pointer to a subdev sink pad
>>> + * @sink:  pointer to a sink pad
>>>   * @flags: the link flags
>>>   *
>>>   * This function searches for fwnode endpoint connections from a source
>>>   * subdevice to a single sink pad, and if suitable connections are found,
>>>   * translates them into media links to that pad. The function can be
>>> - * called by the sink subdevice, in its v4l2-async notifier subdev bound
>>> - * callback, to create links from a bound source subdevice.
>>> + * called by the sink, in its v4l2-async notifier bound callback, to create
>>> + * links from a bound source subdevice.
>>>   *
>>>   * The @flags argument specifies the link flags. The caller shall ensure that
>>>   * the flags are valid regardless of the number of links that may be created.
> 

-- 
Regards,
Vaishnav