Hi Sakari,
On 1/25/19 8:28 AM, Sakari Ailus wrote:
Hi Shuah,
On Thu, Jan 24, 2019 at 01:32:37PM -0700, Shuah Khan wrote:
Media Device Allocator API to allows multiple drivers share a media device. This API solves a very common use-case for media devices where one physical device (an USB stick) provides both audio and video. When such media device exposes a standard USB Audio class, a proprietary Video class, two or more independent drivers will share a single physical USB bridge. In such cases, it is necessary to coordinate access to the shared resource.
Using this API, drivers can allocate a media device with the shared struct device as the key. Once the media device is allocated by a driver, other drivers can get a reference to it. The media device is released when all the references are released.
Thanks for the update. I have to apologise I haven't ended up reviewing the set for some time. After taking a look at the current version, I'm happy to see that a number of issues recognised during earlier review rounds have been addressed.
Would you happen to have a media graph (media-ctl --print-dot and media-ctl -p) from the device? That'd help understanding the device a bit better for those who are not familiar with it.
Please see the attached files for the below. It came in very handy for testing partial graphs as I did bind and unbind of the drivers in this mix.
media-ctl --print-dot and media-ctl --print-topology
thanks, -- Shuah