Re: [PATCH 08/31] media: v4l-core add v4l_enable/disable_media_tuner() helper functions

From: Shuah Khan
Date: Thu Jan 28 2016 - 12:12:24 EST


On 01/28/2016 08:26 AM, Mauro Carvalho Chehab wrote:
> Em Wed, 6 Jan 2016 13:26:57 -0700
> Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> escreveu:
>
>> Add a new interfaces to be used by v4l-core to invoke enable
>> source and disable_source handlers in the media_device. The
>> enable_source helper function invokes the enable_source handler
>> to find tuner entity connected to the decoder and check is it
>> is available or busy. If tuner is available, link is activated
>> and pipeline is started. The disable_source helper function
>> invokes the disable_source handler to deactivate and stop the
>> pipeline.
>>
>> Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
>> ---
>> drivers/media/v4l2-core/v4l2-dev.c | 27 +++++++++++++++++++++++++++
>> include/media/v4l2-dev.h | 4 ++++
>> 2 files changed, 31 insertions(+)
>>
>> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
>> index d8e5994..f06da6e 100644
>> --- a/drivers/media/v4l2-core/v4l2-dev.c
>> +++ b/drivers/media/v4l2-core/v4l2-dev.c
>> @@ -233,6 +233,33 @@ struct video_device *video_devdata(struct file *file)
>> }
>> EXPORT_SYMBOL(video_devdata);
>>
>> +int v4l_enable_media_tuner(struct video_device *vdev)
>
> IMHO, the better is to put those MC ancillary routines on a separate file.
> Hans suggested to add them at v4l2-mc.h and v4l2-mc.h.

ok I can do that.

>
>> +{
>> +#ifdef CONFIG_MEDIA_CONTROLLER
>> + struct media_device *mdev = vdev->entity.graph_obj.mdev;
>> + int ret;
>> +
>> + if (!mdev || !mdev->enable_source)
>> + return 0;
>> + ret = mdev->enable_source(&vdev->entity, &vdev->pipe);
>> + if (ret)
>> + return -EBUSY;
>> + return 0;
>> +#endif /* CONFIG_MEDIA_CONTROLLER */
>> + return 0;
>> +}
>> +EXPORT_SYMBOL_GPL(v4l_enable_media_tuner);
>> +
>> +void v4l_disable_media_tuner(struct video_device *vdev)
>> +{
>> +#ifdef CONFIG_MEDIA_CONTROLLER
>> + struct media_device *mdev = vdev->entity.graph_obj.mdev;
>> +
>> + if (mdev && mdev->disable_source)
>> + mdev->disable_source(&vdev->entity);
>> +#endif /* CONFIG_MEDIA_CONTROLLER */
>> +}
>> +EXPORT_SYMBOL_GPL(v4l_disable_media_tuner);
>>
>> /* Priority handling */
>>
>> diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
>> index eeabf20..68999a3 100644
>> --- a/include/media/v4l2-dev.h
>> +++ b/include/media/v4l2-dev.h
>> @@ -87,6 +87,7 @@ struct video_device
>> #if defined(CONFIG_MEDIA_CONTROLLER)
>> struct media_entity entity;
>> struct media_intf_devnode *intf_devnode;
>> + struct media_pipeline pipe;
>> #endif
>> /* device ops */
>> const struct v4l2_file_operations *fops;
>> @@ -176,6 +177,9 @@ void video_unregister_device(struct video_device *vdev);
>> latter can also be used for video_device->release(). */
>> struct video_device * __must_check video_device_alloc(void);
>>
>> +int v4l_enable_media_tuner(struct video_device *vdev);
>> +void v4l_disable_media_tuner(struct video_device *vdev);
>
> Documentation?

Since I am going to be adding a new source file, I can
add documentation in the same patch.

thanks,
-- Shuah

>
>> +
>> /* this release function frees the vdev pointer */
>> void video_device_release(struct video_device *vdev);
>>


--
Shuah Khan
Sr. Linux Kernel Developer
Open Source Innovation Group
Samsung Research America (Silicon Valley)
shuahkh@xxxxxxxxxxxxxxx | (970) 217-8978