We tracked down the first-0.5s-hdmi-audio-samples-lost problem to the
AC_VERB_SET_CHANNEL_STREAMID command. It is suspected that many HDMI
sinks need some time to adapt to the new state.
The workaround is to avoid changing stream id/format whenever possible.
Proposed by David.
Signed-off-by: David Härdeman <david@xxxxxxxxxxx>
Signed-off-by: Wu Fengguang <fengguang.wu@xxxxxxxxx>
---
sound/pci/hda/patch_intelhdmi.c | 28 ++++++++++++++++++++++++++--
1 file changed, 26 insertions(+), 2 deletions(-)
--- sound-2.6.orig/sound/pci/hda/patch_intelhdmi.c 2009-11-05 13:56:58.000000000 +0800
+++ sound-2.6/sound/pci/hda/patch_intelhdmi.c 2009-11-05 13:58:05.000000000 +0800
@@ -772,6 +772,31 @@ static void intel_hdmi_unsol_event(struc
* Callbacks
*/
+static void hdmi_setup_stream(struct hda_codec *codec, hda_nid_t nid,
+ u32 stream_tag, int format)
+{
+ int tag;
+ int fmt;
+
+ tag = snd_hda_codec_read(codec, nid, 0, AC_VERB_GET_CONV, 0) >> 4;
+ fmt = snd_hda_codec_read(codec, nid, 0, AC_VERB_GET_STREAM_FORMAT, 0);
+
+ snd_printdd("hdmi_setup_stream: "
+ "NID=0x%x, %sstream=0x%x, %sformat=0x%x\n",
+ nid,
+ tag == stream_tag ? "" : "new-",
+ stream_tag,
+ fmt == format ? "" : "new-",
+ format);
+
+ if (tag != stream_tag)
+ snd_hda_codec_write(codec, nid, 0,
+ AC_VERB_SET_CHANNEL_STREAMID, stream_tag << 4);
+ if (fmt != format)
+ snd_hda_codec_write(codec, nid, 0,
+ AC_VERB_SET_STREAM_FORMAT, format);
+}
+
static int intel_hdmi_playback_pcm_prepare(struct hda_pcm_stream *hinfo,
struct hda_codec *codec,
unsigned int stream_tag,
@@ -783,7 +808,7 @@ static int intel_hdmi_playback_pcm_prepa
hdmi_setup_audio_infoframe(codec, hinfo->nid, substream);
- snd_hda_codec_setup_stream(codec, hinfo->nid, stream_tag, 0, format);
+ hdmi_setup_stream(codec, hinfo->nid, stream_tag, format);
return 0;
}
@@ -791,7 +816,6 @@ static int intel_hdmi_playback_pcm_clean
struct hda_codec *codec,
struct snd_pcm_substream *substream)
{
- snd_hda_codec_cleanup_stream(codec, hinfo->nid);
return 0;
}
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