[PATCH 1/2] ALSA: hda/hdmi: fix failures at PCM open on Intel ICL and later

[PATCH 1/2] ALSA: hda/hdmi: fix failures at PCM open on Intel ICL and later

[Kai Vehmanen]

When HDMI PCM devices are opened in a specific order, with at least one
HDMI/DP receiver connected, ALSA PCM open fails to -EBUSY on the
connected monitor, on recent Intel platforms (ICL/JSL and newer). While
this is not a typical sequence, at least Pulseaudio does this every time
when it is started, to discover the available PCMs.

The rootcause is an invalid assumption in hdmi_add_pin(), where the
total number of converters is assumed to be known at the time the
function is called. On older Intel platforms this held true, but after
ICL/JSL, the order how pins and converters are in the subnode list as
returned by snd_hda_get_sub_nodes(), was changed. As a result,
information for some converters was not stored to per_pin->mux_nids.
And this means some pins cannot be connected to all converters, and
application instead gets -EBUSY instead at open.

The assumption that converters are always before pins in the subnode
list, is not really a valid one. Fix the problem in hdmi_parse_codec()
by introducing separate loops for discovering converters and pins.

BugLink: https://github.com/thesofproject/linux/issues/1978
BugLink: https://github.com/thesofproject/linux/issues/2216
BugLink: https://github.com/thesofproject/linux/issues/2217
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
---
 sound/pci/hda/patch_hdmi.c | 36 +++++++++++++++++++++++-------------
 1 file changed, 23 insertions(+), 13 deletions(-)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index e2b21ef5d7d1..295cc5a989d5 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -1804,33 +1804,43 @@ static int hdmi_add_cvt(struct hda_codec *codec, hda_nid_t cvt_nid)
 
 static int hdmi_parse_codec(struct hda_codec *codec)
 {
-	hda_nid_t nid;
+	hda_nid_t start_nid;
+	unsigned int caps;
 	int i, nodes;
 
-	nodes = snd_hda_get_sub_nodes(codec, codec->core.afg, &nid);
-	if (!nid || nodes < 0) {
+	nodes = snd_hda_get_sub_nodes(codec, codec->core.afg, &start_nid);
+	if (!start_nid || nodes < 0) {
 		codec_warn(codec, "HDMI: failed to get afg sub nodes\n");
 		return -EINVAL;
 	}
 
-	for (i = 0; i < nodes; i++, nid++) {
-		unsigned int caps;
-		unsigned int type;
+	/*
+	 * hdmi_add_pin() assumes total amount of converters to
+	 * be known, so first discover all converters
+	 */
+	for (i = 0; i < nodes; i++) {
+		hda_nid_t nid = start_nid + i;
 
 		caps = get_wcaps(codec, nid);
-		type = get_wcaps_type(caps);
 
 		if (!(caps & AC_WCAP_DIGITAL))
 			continue;
 
-		switch (type) {
-		case AC_WID_AUD_OUT:
+		if (get_wcaps_type(caps) == AC_WID_AUD_OUT)
 			hdmi_add_cvt(codec, nid);
-			break;
-		case AC_WID_PIN:
+	}
+
+	/* discover audio pins */
+	for (i = 0; i < nodes; i++) {
+		hda_nid_t nid = start_nid + i;
+
+		caps = get_wcaps(codec, nid);
+
+		if (!(caps & AC_WCAP_DIGITAL))
+			continue;
+
+		if (get_wcaps_type(caps) == AC_WID_PIN)
 			hdmi_add_pin(codec, nid);
-			break;
-		}
 	}
 
 	return 0;
-- 
2.27.0

[PATCH 2/2] ALSA: hda/hdmi: improve debug traces for stream lookups

[Kai Vehmanen]

The HDMI codec driver has two debug traces printed from different
functions but with identical message content:

"HDMI: hinfo 000000006a6b84d9 not registered"

Fix this duplication and also add a bit more context in addition to raw
object pointer, to help analysis of kernel logs.

Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
---
 sound/pci/hda/patch_hdmi.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 295cc5a989d5..41eaa89660c3 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -259,7 +259,7 @@ static int hinfo_to_pcm_index(struct hda_codec *codec,
 		if (get_pcm_rec(spec, pcm_idx)->stream == hinfo)
 			return pcm_idx;
 
-	codec_warn(codec, "HDMI: hinfo %p not registered\n", hinfo);
+	codec_warn(codec, "HDMI: hinfo %p not tied to a PCM\n", hinfo);
 	return -EINVAL;
 }
 
@@ -277,7 +277,8 @@ static int hinfo_to_pin_index(struct hda_codec *codec,
 			return pin_idx;
 	}
 
-	codec_dbg(codec, "HDMI: hinfo %p not registered\n", hinfo);
+	codec_dbg(codec, "HDMI: hinfo %p (pcm %d) not registered\n", hinfo,
+		  hinfo_to_pcm_index(codec, hinfo));
 	return -EINVAL;
 }
 
-- 
2.27.0

Re: [PATCH 2/2] ALSA: hda/hdmi: improve debug traces for stream lookups

[Takashi Iwai]

On Fri, 03 Jul 2020 17:38:18 +0200,
Kai Vehmanen wrote:
> 
> The HDMI codec driver has two debug traces printed from different
> functions but with identical message content:
> 
> "HDMI: hinfo 000000006a6b84d9 not registered"
> 
> Fix this duplication and also add a bit more context in addition to raw
> object pointer, to help analysis of kernel logs.
> 
> Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>

Thanks, applied now.


Takashi

Re: [PATCH 1/2] ALSA: hda/hdmi: fix failures at PCM open on Intel ICL and later

[Takashi Iwai]

On Fri, 03 Jul 2020 17:38:17 +0200,
Kai Vehmanen wrote:
> 
> When HDMI PCM devices are opened in a specific order, with at least one
> HDMI/DP receiver connected, ALSA PCM open fails to -EBUSY on the
> connected monitor, on recent Intel platforms (ICL/JSL and newer). While
> this is not a typical sequence, at least Pulseaudio does this every time
> when it is started, to discover the available PCMs.
> 
> The rootcause is an invalid assumption in hdmi_add_pin(), where the
> total number of converters is assumed to be known at the time the
> function is called. On older Intel platforms this held true, but after
> ICL/JSL, the order how pins and converters are in the subnode list as
> returned by snd_hda_get_sub_nodes(), was changed. As a result,
> information for some converters was not stored to per_pin->mux_nids.
> And this means some pins cannot be connected to all converters, and
> application instead gets -EBUSY instead at open.
> 
> The assumption that converters are always before pins in the subnode
> list, is not really a valid one. Fix the problem in hdmi_parse_codec()
> by introducing separate loops for discovering converters and pins.
> 
> BugLink: https://github.com/thesofproject/linux/issues/1978
> BugLink: https://github.com/thesofproject/linux/issues/2216
> BugLink: https://github.com/thesofproject/linux/issues/2217
> Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>

Thanks, applied.


Takashi