diff mbox series

[v12,15/30] media: subdev: add v4l2_subdev_set_routing helper()

Message ID 20220727103639.581567-16-tomi.valkeinen@ideasonboard.com (mailing list archive)
State New, archived
Headers show
Series v4l: routing and streams support | expand

Commit Message

Tomi Valkeinen July 27, 2022, 10:36 a.m. UTC 
Add a helper function to set the subdev routing. The helper can be used
from subdev driver's set_routing op to store the routing table.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 27 +++++++++++++++++++++++++++
 include/media/v4l2-subdev.h           | 16 ++++++++++++++++
 2 files changed, 43 insertions(+)

Comments

Sakari Ailus Aug. 1, 2022, 6:59 a.m. UTC | #1 
Moi,

On Wed, Jul 27, 2022 at 01:36:24PM +0300, Tomi Valkeinen wrote:
> Add a helper function to set the subdev routing. The helper can be used
> from subdev driver's set_routing op to store the routing table.
> 
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
> ---
>  drivers/media/v4l2-core/v4l2-subdev.c | 27 +++++++++++++++++++++++++++
>  include/media/v4l2-subdev.h           | 16 ++++++++++++++++
>  2 files changed, 43 insertions(+)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
> index befd00ebf381..0b841cf74c74 100644
> --- a/drivers/media/v4l2-core/v4l2-subdev.c
> +++ b/drivers/media/v4l2-core/v4l2-subdev.c
> @@ -1176,6 +1176,33 @@ int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
>  }
>  EXPORT_SYMBOL_GPL(v4l2_subdev_get_fmt);
>  
> +int v4l2_subdev_set_routing(struct v4l2_subdev *sd,
> +			    struct v4l2_subdev_state *state,
> +			    struct v4l2_subdev_krouting *routing)
> +{
> +	struct v4l2_subdev_krouting *dst = &state->routing;
> +	const struct v4l2_subdev_krouting *src = routing;
> +
> +	lockdep_assert_held(state->lock);
> +
> +	kfree(dst->routes);
> +	dst->routes = NULL;
> +	dst->num_routes = 0;

Shouldn't you keep the old routing around until memory allocation (and
anything else that can fail) has succeeded?

> +
> +	if (src->num_routes > 0) {
> +		dst->routes = kmemdup(src->routes,
> +				      src->num_routes * sizeof(*src->routes),
> +				      GFP_KERNEL);
> +		if (!dst->routes)
> +			return -ENOMEM;
> +
> +		dst->num_routes = src->num_routes;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(v4l2_subdev_set_routing);
> +
>  #endif /* CONFIG_VIDEO_V4L2_SUBDEV_API */
>  
>  #endif /* CONFIG_MEDIA_CONTROLLER */
> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> index decd1e1c3d39..37081a2e6697 100644
> --- a/include/media/v4l2-subdev.h
> +++ b/include/media/v4l2-subdev.h
> @@ -1407,6 +1407,22 @@ v4l2_subdev_lock_and_get_active_state(struct v4l2_subdev *sd)
>  int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
>  			struct v4l2_subdev_format *format);
>  
> +/**
> + * v4l2_subdev_set_routing() - Set given routing to subdev state
> + * @sd: The subdevice
> + * @state: The subdevice state
> + * @routing: Routing that will be copied to subdev state
> + *
> + * This will release old routing table (if any) from the state, allocate
> + * enough space for the given routing, and copy the routing.
> + *
> + * This can be used from the subdev driver's set_routing op, after validating
> + * the routing.
> + */
> +int v4l2_subdev_set_routing(struct v4l2_subdev *sd,
> +			    struct v4l2_subdev_state *state,
> +			    struct v4l2_subdev_krouting *routing);
> +
>  #endif /* CONFIG_VIDEO_V4L2_SUBDEV_API */
>  
>  #endif /* CONFIG_MEDIA_CONTROLLER */
Tomi Valkeinen Aug. 1, 2022, 7:38 a.m. UTC | #2 
On 01/08/2022 09:59, Sakari Ailus wrote:
> Moi,
> 
> On Wed, Jul 27, 2022 at 01:36:24PM +0300, Tomi Valkeinen wrote:
>> Add a helper function to set the subdev routing. The helper can be used
>> from subdev driver's set_routing op to store the routing table.
>>
>> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>> Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
>> ---
>>   drivers/media/v4l2-core/v4l2-subdev.c | 27 +++++++++++++++++++++++++++
>>   include/media/v4l2-subdev.h           | 16 ++++++++++++++++
>>   2 files changed, 43 insertions(+)
>>
>> diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
>> index befd00ebf381..0b841cf74c74 100644
>> --- a/drivers/media/v4l2-core/v4l2-subdev.c
>> +++ b/drivers/media/v4l2-core/v4l2-subdev.c
>> @@ -1176,6 +1176,33 @@ int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
>>   }
>>   EXPORT_SYMBOL_GPL(v4l2_subdev_get_fmt);
>>   
>> +int v4l2_subdev_set_routing(struct v4l2_subdev *sd,
>> +			    struct v4l2_subdev_state *state,
>> +			    struct v4l2_subdev_krouting *routing)
>> +{
>> +	struct v4l2_subdev_krouting *dst = &state->routing;
>> +	const struct v4l2_subdev_krouting *src = routing;
>> +
>> +	lockdep_assert_held(state->lock);
>> +
>> +	kfree(dst->routes);
>> +	dst->routes = NULL;
>> +	dst->num_routes = 0;
> 
> Shouldn't you keep the old routing around until memory allocation (and
> anything else that can fail) has succeeded?

Indeed, good catch! I think v4l2_subdev_init_stream_configs() also needs 
improving.

  Tomi
diff mbox series

Patch

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index befd00ebf381..0b841cf74c74 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -1176,6 +1176,33 @@  int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
 }
 EXPORT_SYMBOL_GPL(v4l2_subdev_get_fmt);
 
+int v4l2_subdev_set_routing(struct v4l2_subdev *sd,
+			    struct v4l2_subdev_state *state,
+			    struct v4l2_subdev_krouting *routing)
+{
+	struct v4l2_subdev_krouting *dst = &state->routing;
+	const struct v4l2_subdev_krouting *src = routing;
+
+	lockdep_assert_held(state->lock);
+
+	kfree(dst->routes);
+	dst->routes = NULL;
+	dst->num_routes = 0;
+
+	if (src->num_routes > 0) {
+		dst->routes = kmemdup(src->routes,
+				      src->num_routes * sizeof(*src->routes),
+				      GFP_KERNEL);
+		if (!dst->routes)
+			return -ENOMEM;
+
+		dst->num_routes = src->num_routes;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_subdev_set_routing);
+
 #endif /* CONFIG_VIDEO_V4L2_SUBDEV_API */
 
 #endif /* CONFIG_MEDIA_CONTROLLER */
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index decd1e1c3d39..37081a2e6697 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1407,6 +1407,22 @@  v4l2_subdev_lock_and_get_active_state(struct v4l2_subdev *sd)
 int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
 			struct v4l2_subdev_format *format);
 
+/**
+ * v4l2_subdev_set_routing() - Set given routing to subdev state
+ * @sd: The subdevice
+ * @state: The subdevice state
+ * @routing: Routing that will be copied to subdev state
+ *
+ * This will release old routing table (if any) from the state, allocate
+ * enough space for the given routing, and copy the routing.
+ *
+ * This can be used from the subdev driver's set_routing op, after validating
+ * the routing.
+ */
+int v4l2_subdev_set_routing(struct v4l2_subdev *sd,
+			    struct v4l2_subdev_state *state,
+			    struct v4l2_subdev_krouting *routing);
+
 #endif /* CONFIG_VIDEO_V4L2_SUBDEV_API */
 
 #endif /* CONFIG_MEDIA_CONTROLLER */