On Fri, Jun 21, 2019 at 5:12 AM Daniel Vetter <daniel@xxxxxxxx> wrote: > > Massively cutting this thread, since halfway through in my previous reply > I realized that maybe hdmi_codec is a much better starting point. > ACK > On Thu, Jun 20, 2019 at 09:23:23PM +0800, Cheng-yi Chiang wrote: > > On Thu, Jun 20, 2019 at 5:25 PM Daniel Vetter <daniel@xxxxxxxx> wrote: > > > Yeah fully agreeing that hdmi_audio_code is probably a better starting > > > point. Problem is that becuase hdmi_codec is built on top of platform > > > device it's quite a bit harder to extend with callbacks and things like > > > that, without breaking the driver model. > > > > > > I need to think about this more, but if all we need to look at is > > > hdmi_codec, then I think this becomes a lot easier. And we can ignore > > > drm_audio_component.h completely. > > > > > > It is surprising that you think this way. > > Maybe the original patch before hdmi-notifier was introduced is the > > better way to solve this issue, if we only need to look at hdmi_codec. > > > > The history of hdmi_codec driver is in this patch series: > > > > https://lore.kernel.org/patchwork/patch/539656/ > > Hm, this doesn't seem to be the hdmi_codec driver I meant, but another, > new one. I was talking about SND_SOC_HDMI_CODEC. > Yes you are right. They are different codec drivers. Sorry for the confusion. What I meant was that my use case on RK3288 was using dw-hdmi-audio.c codec driver, which was later replaced by a more general version hdmi-codec.c. > > There was a callback mechanism implemented between dw-hdmi and hdmi > > codec driver. > > It was later consolidated by Doug in this patch for better jack status > > reporting: > > > > https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/303573/ > > Hm that still seems entirely separate hdmi-codec specific to dw-hdmi only > ... > Again you are right. Sorry for the confusion. What I meant is that this callback mechanism should work on hdmi-codec.c driver as well. > > I am not sure why the original patch series did not get fully accepted > > in the upstream. > > It was quite long time ago. > > > > But if you think this might be the right way to do, then it is even > > better for us because the patch series and Doug's patch had been quite > > stable > > on our RK3288 products for about four years with plenty of users, so > > we have much higher confidence in them. > > I can rebase and clean up them and post another patch for review. > > > > Please let me know what approach you feel is better. > > Thanks again! > > Not sure we're talking about the same. What I had in mind is to add jack > status to the hdmi-codec.c stuff, which is used by multiple soc drm > display drivers already. Looking at git grep output, there seems to be > already some support for dw-hdmi synopsys drm_bridge driver. I thought of > extending that. Does that not work for you? > I think extending current interface will work. There is a struct hdmi_codec_pdata to let ALSA codec driver access some ops through platform data. And after this patch https://lore.kernel.org/patchwork/patch/692324/ ALSA codec driver can get access to the struct on DRM side. Based on this I can add a new ops to register callback function for jack status. It will be similar to Doug's chromium patch above. I think that is quite a feasible way, and can benefit all boards using hdmi-codec.c. Thanks a lot!! > Thanks, Daniel > -- > Daniel Vetter > Software Engineer, Intel Corporation > http://blog.ffwll.ch
