Re: Regression: Kernel 4.6 DisplayPort Audio

[Takashi Iwai]

On Wed, 11 May 2016 10:32:07 +0200,
Daniel Exner wrote:
> 
> Hi,
> 
> (Please keep me CC as I am currently not subscribed to LKML or any other
> Linux Kernel Dev ML, thanks)
> 
> Since very first 4.6 rc1 the speakers integrated in my monitor (Dell
> U3415W) stopped working. It is connected via DisplayPort from a ATI R7 270X.
> 
> Same setup works just fine in 4.5.3.
> 
> The bug report about this is:
> 
> https://bugzilla.kernel.org/show_bug.cgi?id=114981
> 
> I managed to bisect this down to:
> 
> commit 739ffee97ed550a2899a925ed3f260fa1e8fa955
> Author: Subhransu S. Prusty <subhransu.s.prusty@xxxxxxxxx>
> Date:   Fri Mar 4 19:59:49 2016 +0530
> 
>     ALSA: hda - Add hdmi chmap verb programming ops to chmap object
> 
> But I cannot easily revert this from current rc7.
> Please make me a happy DP Audio User again :)
> 
> I can provide further informations or test possible patches.

If the commit above alone breaks, does the patch below change the
behavior?  Through a quick look at it, some ops are overridden only
conditionally while the older code always overwrote them.


thanks,

Takashi

---
diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index d2e57c72ba94..d0d5ad8beac5 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -3549,6 +3549,9 @@ static int patch_atihdmi(struct hda_codec *codec)
 	spec->ops.pin_hbr_setup = atihdmi_pin_hbr_setup;
 	spec->ops.setup_stream = atihdmi_setup_stream;
 
+	spec->chmap.ops.pin_get_slot_channel = atihdmi_pin_get_slot_channel;
+	spec->chmap.ops.pin_set_slot_channel = atihdmi_pin_set_slot_channel;
+
 	if (!has_amd_full_remap_support(codec)) {
 		/* override to ATI/AMD-specific versions with pairwise mapping */
 		spec->chmap.ops.chmap_cea_alloc_validate_get_type =
@@ -3556,10 +3559,6 @@ static int patch_atihdmi(struct hda_codec *codec)
 		spec->chmap.ops.cea_alloc_to_tlv_chmap =
 				atihdmi_paired_cea_alloc_to_tlv_chmap;
 		spec->chmap.ops.chmap_validate = atihdmi_paired_chmap_validate;
-		spec->chmap.ops.pin_get_slot_channel =
-				atihdmi_pin_get_slot_channel;
-		spec->chmap.ops.pin_set_slot_channel =
-				atihdmi_pin_set_slot_channel;
 	}
 
 	/* ATI/AMD converters do not advertise all of their capabilities */