We found that enabling/disabling HDMI audio pin out at stream start/stop
time will kill the leading 500ms or so sound samples. Avoid this by enabling
pin out once and for ever at module loading time.
The leading ~500ms audio samples will still be lost when switching from
X-channel playback to Y-channel playback where X != Y. However there's no
much we can do about it: the audio infoframe has to change and it looks like
either G45 or YAMAHA requires some time to switch the configuration.
Signed-off-by: Wu Fengguang <fengguang.wu@xxxxxxxxx>
---
sound/pci/hda/patch_intelhdmi.c | 42 +++++++++++++-----------------
1 file changed, 19 insertions(+), 23 deletions(-)
--- mm.orig/sound/pci/hda/patch_intelhdmi.c
+++ mm/sound/pci/hda/patch_intelhdmi.c
@@ -49,11 +49,6 @@ static struct hda_verb pinout_enable_ver
{} /* terminator */
};
-static struct hda_verb pinout_disable_verb[] = {
- {PIN_NID, AC_VERB_SET_PIN_WIDGET_CONTROL, 0x00},
- {}
-};
-
static struct hda_verb unsolicited_response_verb[] = {
{PIN_NID, AC_VERB_SET_UNSOLICITED_ENABLE, AC_USRSP_EN |
INTEL_HDMI_EVENT_TAG},
@@ -248,10 +243,6 @@ static void hdmi_write_dip_byte(struct h
static void hdmi_enable_output(struct hda_codec *codec)
{
- /* Enable Audio InfoFrame Transmission */
- hdmi_set_dip_index(codec, PIN_NID, 0x0, 0x0);
- snd_hda_codec_write(codec, PIN_NID, 0, AC_VERB_SET_HDMI_DIP_XMIT,
- AC_DIPXMIT_BEST);
/* Unmute */
if (get_wcaps(codec, PIN_NID) & AC_WCAP_OUT_AMP)
snd_hda_codec_write(codec, PIN_NID, 0,
@@ -260,17 +251,24 @@ static void hdmi_enable_output(struct hd
snd_hda_sequence_write(codec, pinout_enable_verb);
}
-static void hdmi_disable_output(struct hda_codec *codec)
+/*
+ * Enable Audio InfoFrame Transmission
+ */
+static void hdmi_start_infoframe_trans(struct hda_codec *codec)
{
- snd_hda_sequence_write(codec, pinout_disable_verb);
- if (get_wcaps(codec, PIN_NID) & AC_WCAP_OUT_AMP)
- snd_hda_codec_write(codec, PIN_NID, 0,
- AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_MUTE);
+ hdmi_set_dip_index(codec, PIN_NID, 0x0, 0x0);
+ snd_hda_codec_write(codec, PIN_NID, 0, AC_VERB_SET_HDMI_DIP_XMIT,
+ AC_DIPXMIT_BEST);
+}
- /*
- * FIXME: noises may arise when playing music after reloading the
- * kernel module, until the next X restart or monitor repower.
- */
+/*
+ * Disable Audio InfoFrame Transmission
+ */
+static void hdmi_stop_infoframe_trans(struct hda_codec *codec)
+{
+ hdmi_set_dip_index(codec, PIN_NID, 0x0, 0x0);
+ snd_hda_codec_write(codec, PIN_NID, 0, AC_VERB_SET_HDMI_DIP_XMIT,
+ AC_DIPXMIT_DISABLE);
}
static int hdmi_get_channel_count(struct hda_codec *codec)
@@ -489,6 +487,7 @@ static void hdmi_setup_audio_infoframe(s
hdmi_setup_channel_mapping(codec, &ai);
hdmi_fill_audio_infoframe(codec, &ai);
+ hdmi_start_infoframe_trans(codec);
}
@@ -566,7 +565,7 @@ static int intel_hdmi_playback_pcm_close
{
struct intel_hdmi_spec *spec = codec->spec;
- hdmi_disable_output(codec);
+ hdmi_stop_infoframe_trans(codec);
return snd_hda_multi_out_dig_close(codec, &spec->multiout);
}
@@ -586,8 +585,6 @@ static int intel_hdmi_playback_pcm_prepa
hdmi_setup_audio_infoframe(codec, substream);
- hdmi_enable_output(codec);
-
return 0;
}
@@ -632,8 +629,7 @@ static int intel_hdmi_build_controls(str
static int intel_hdmi_init(struct hda_codec *codec)
{
- /* disable audio output as early as possible */
- hdmi_disable_output(codec);
+ hdmi_enable_output(codec);
snd_hda_sequence_write(codec, unsolicited_response_verb);
--
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