On Fri, 06 Nov 2015 06:33:48 +0100, Libin Yang wrote: > > Hi Takashi, > > On 11/04/2015 01:38 PM, Libin Yang wrote: > > On 11/04/2015 12:44 AM, Takashi Iwai wrote: > >> On Tue, 03 Nov 2015 09:22:53 +0100, > >> libin.yang@xxxxxxxxxxxxxxx wrote: > >>> > >>> From: Libin Yang <libin.yang@xxxxxxxxx> > >>> > >>> Allocate the PCM based on the number of pin and device entry. > >>> The number of PCM is pin num plus device entry number per pin. > >>> For example, on Intel platform, it will be 5 PCMs. > >>> > >>> Do not attach the PCM to pin in initialization. > >>> Dynamically attach PCM to pin when monitor is connected > >>> in HDMI audio codec driver. > >>> > >>> When monitor is disconnected, detach the PCM from the pin. > >>> And if the audio is playing, stop the playback. > >>> > >>> The below is the example of device entry and PCM binding: > >>> For a monitor is plugged in, we need to dynamically assign > >>> this monitor to 5 PCM devices (on Intel platform): > >>> For a monitor at pin nid 0x05, dev index 0, it will prefer PCM 3 > >>> For a monitor at pin nid 0x06, dev index 0, it will prefer PCM 7 > >>> For a monitor at pin nid 0x07, dev index 0, it will prefer PCM 8 > >>> For a monitor at dev index 1 (any pin), it will prefer PCM 9 > >>> For a monitor at dev index 2 (any pin), it will prefer PCM 10 > >>> > >>> If the preferred PCM is not available, try PCM in this order: > >>> 9, 10, 3, 7 ,8. > >>> > >>> Signed-off-by: Libin Yang <libin.yang@xxxxxxxxxxxxxxx> > >> > >> We should split the changes to a few patches here. For example, > >> stopping the stream at discussion is basically an implementation > >> independent from the MST itself. IOW, the dynamic attach/detach can > >> be implemented and tested even without MST support. Let's code them > >> at first, then add MST support. > > > > This patch actually doesn't depend on MST. I use the dev_num to > > determine how many PCMs to be created. > > > > To Split the patch, how about I create the PCM number based the pin > > number in the patch? > > > >> > >> Also, it's an open question whether we apply the dynamic attach/detach > >> to all devices that use the generic hdmi framework. It means > >> including AMD and Nvidia. You hard-coded it to be applied > >> unconditionally. Would it break anything potentially...? > > > > I have no other verdors platforms to test. But it seems to be OK on > > other platforms. The impact is, i think, it will stop the stream when > > monitor is disconnected. Should we apply the code by judging whehter > > it is Intel platform? > > If you are concerning the impact on other vendors, what about I create > a separate mst codec driver? In the driver, I will still use virtual > pin, but other vendors platform will not be supported at the moment. > Other vendors can add their patches to the new codec driver to support > their own mst audio. No, it's not the option. Such a behavior change is the big burden to user-space. We should provide consistent behavior as much as possible. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
