[alsa-devel] Support MCP89 hdmi audio

[Takashi Iwai]

At Wed, 21 Jul 2010 19:45:09 +0800,
Wei Ni wrote:
> 
> Hi, all
> I'm an Nvidia engineer, I maintain the nvidia linux hdmi audio driver.
> 
> An end-user report a problem with his TV attached to an MCP89.
> ALSA won't send audio to it, because
> PD=0:
> HDMI hot plug event: Pin=5 Presence_Detect=1 ELD_Valid=0
> HDMI hot plug event: Pin=5 Presence_Detect=0 ELD_Valid=1
> 
> As you know, in linux driver patch_hdmi.c, it use (pind && eldv)
> in unsolicited events. So the driver can't detect the monitor.
> 
> >From the HAD specification
> (http://download.intel.com/standards/hdaudio/pdf/HDA036.pdf):
> 
> Original text for Unsolicited Response PD bit:
> 
> Presence Detect: When this bit is set, sense measurement has
> changed on the pin widget and software can use the pin sense
> control verb to determine the current pin sense data state.
> For analog pin widgets, this UR means that Presence Detect or
> Impedance has changed on the pin widget.
> For digital pin widgets, including HDMI pin widgets, this means
> that presence detect (and optionally ELD valid bit) has
> **changed**. [my emphasis]
> 
> Updated text for Unsolicted Response PD bit:
> 
> Presence Detect: This bit reflects the **present** [my
> emphasis] state of the Pin Sense Presence Detect bit when the
> unsolicited response is triggered. Software can optionally use
> the pin sense control verb to determine the latest pin sense
> data state. This bit implementation is only required for
> digital display pin widget. Non digital display pin widget is
> optional to implement this bit.
> 
> For our MCP89, the values indicates the change of status of PD, not the actual value of PD,
> which follows older description of UR for PD bit.
> 
> So could we add a workaround for MCP89? We could use Pin Sense to determine again in
> unsolicited events. If it return 0xc0000000, it means PD=1 and ELVD=1.
> Or do you have any suggestions?

Yes.  The patch below does similar thing.
Could you give it a try?


thanks,

Takashi

---
diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 86067ee..2fc5396 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -52,6 +52,10 @@ struct hdmi_spec {
 	 */
 	struct hda_multi_out multiout;
 	unsigned int codec_type;
+
+	/* misc flags */
+	/* PD bit indicates only the update, not the current state */
+	unsigned int old_pin_detect:1;
 };
 
 
@@ -616,6 +620,9 @@ static void hdmi_setup_audio_infoframe(struct hda_codec *codec, hda_nid_t nid,
  * Unsolicited events
  */
 
+static void hdmi_present_sense(struct hda_codec *codec, hda_nid_t pin_nid,
+			       struct hdmi_eld *eld);
+
 static void hdmi_intrinsic_event(struct hda_codec *codec, unsigned int res)
 {
 	struct hdmi_spec *spec = codec->spec;
@@ -632,6 +639,12 @@ static void hdmi_intrinsic_event(struct hda_codec *codec, unsigned int res)
 	if (index < 0)
 		return;
 
+	if (spec->old_pin_detect) {
+		if (pind)
+			hdmi_present_sense(codec, tag, &spec->sink_eld[index]);
+		pind = spec->sink_eld[index].monitor_present;
+	}
+
 	spec->sink_eld[index].monitor_present = pind;
 	spec->sink_eld[index].eld_valid = eldv;
 
diff --git a/sound/pci/hda/patch_nvhdmi.c b/sound/pci/hda/patch_nvhdmi.c
index 3c10c0b..b0652ac 100644
--- a/sound/pci/hda/patch_nvhdmi.c
+++ b/sound/pci/hda/patch_nvhdmi.c
@@ -478,6 +478,7 @@ static int patch_nvhdmi_8ch_89(struct hda_codec *codec)
 
 	codec->spec = spec;
 	spec->codec_type = HDA_CODEC_NVIDIA_MCP89;
+	spec->old_pin_detect = 1;
 
 	if (hdmi_parse_codec(codec) < 0) {
 		codec->spec = NULL;
@@ -508,6 +509,7 @@ static int patch_nvhdmi_8ch_7x(struct hda_codec *codec)
 	spec->multiout.max_channels = 8;
 	spec->multiout.dig_out_nid = nvhdmi_master_con_nid_7x;
 	spec->codec_type = HDA_CODEC_NVIDIA_MCP7X;
+	spec->old_pin_detect = 1;
 
 	codec->patch_ops = nvhdmi_patch_ops_8ch_7x;
 
@@ -528,6 +530,7 @@ static int patch_nvhdmi_2ch(struct hda_codec *codec)
 	spec->multiout.max_channels = 2;
 	spec->multiout.dig_out_nid = nvhdmi_master_con_nid_7x;
 	spec->codec_type = HDA_CODEC_NVIDIA_MCP7X;
+	spec->old_pin_detect = 1;
 
 	codec->patch_ops = nvhdmi_patch_ops_2ch;