Massively cutting this thread, since halfway through in my previous reply I realized that maybe hdmi_codec is a much better starting point. 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. > 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 ... > 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? Thanks, Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch