At Thu, 11 Sep 2014 11:07:10 +0200, David Henningsson wrote:
On 2014-09-11 09:47, Adam Richter wrote:
Hi.
Hi Adam,
Interesting problem. Could you submit alsa-info ( http://www.alsa-project.org/alsa-info.sh ) and point us to it? It makes it possible to run the code in an emulator.
This is a bug and suggested temporary fix that I originally posted to the linux-sound mailing list about a month and a half ago. I am grateful to Takashi Awai for informing me after my follow-up inquiry about it today that I should submit it to the alsa-devel mailing list instead. Please feel free to redirect me further if appropriate. I did not notice any contact information for sound/pci/hda in linux-3.16-rc4/MAINATINERS.
Anyhow, here is the bug report and a one line proposed temporary fix.
The "model=no-jd" argument has not initialized the analog audio output jack correctly for me since linux-3.9-rc1 (if I recall correctly) through linux-3.17-rc4, although I have not tried every release candidate in between.
A lot of things changed with 3.9, so that makes sense. Btw, "model=no-jd" works only for specific machines. You can use the hint "jack-detect=0" instead.
The symptom is that, on a computer with an analog audio output jack that has incorrect jack sense (a hardware bug), audio output is completely muted until I physically replug the cable, even though I specified "model=no-jd" as an argument to the snd-hda-intel kernel module, which is supposed to cause the kernel to ignore the jack sense reported by hardware and just drive the audio output even if the hardware jack sense indicates nothing is plugged in. This problem did not occur until approximate Linux 3.9-rc1.
I have found a few single line workarounds that work, of which my favorite is the following (also attached to this email, in case any mailer subjects this message to reformatting), because it does not add code to anything that gets called frequently.
--- linux-3.17.0-rc4-64bit/sound/pci/hda/hda_jack.c.orig 2014-09-07 16:09:43.000000000 -0700 +++ linux-3.17.0-rc4-64bit/sound/pci/hda/hda_jack.c 2014-09-10 18:41:53.422900040 -0700 @@ -106,6 +106,7 @@ snd_hda_jack_tbl_new(struct hda_codec *c jack->nid = nid; jack->jack_dirty = 1; jack->tag = codec->jacktbl.used;
- jack->phantom_jack = codec->no_jack_detect; return jack; } EXPORT_SYMBOL_GPL(snd_hda_jack_tbl_new);
Signed-off-by: Adam J. Richter adam_richter2004@yahoo.com
I consider this a workaround rather than than a perfect fix, because I think the underlying problem seems to be some kind of initialization order issue that I don't fully understand. Basically, by the time jack->phantom_jack was being set, some caller had already called jack_detect_update(), which loaded the incorrect jack sense result from hardware and cleared jack->jack_dirty, so the jack sense would not be set again. At least that is what I think the underlying problem probably is.
Also, if a change like this is to be integrated, I'd like to know if it might be better for the line that I added to be:
jack->phantom_jack = !is_jack_detectable(codec, nid);Yes, this would probably be better.
I guess that somehow snd_hda_jack_enable_callback gets called for the phantom jack, but I'm not sure exactly how (alsa-info would help).
Nevertheless I'm attaching a patch. I assume it also resolves your problem?
Takashi, what do you think of the attached patch?
Ah, "attached" was meant *your* attached patch. Let me see...
From e5ce94c6156d1c588f29745ade06d1d76c87a0a1 Mon Sep 17 00:00:00 2001 From: David Henningsson david.henningsson@canonical.com Date: Thu, 11 Sep 2014 11:04:42 +0200 Subject: [PATCH] ALSA: hda - Do not enable unsol events on phantom jacks
To make sure we don't enable unsol events on phantom jacks, we move the logic for determining what a phantom jack is to snd_hda_jack_tbl_new.
Reported-by: Adam Richter adam_richter2004@yahoo.com Signed-off-by: David Henningsson david.henningsson@canonical.com
sound/pci/hda/hda_jack.c | 35 +++++++++++++++++++---------------- 1 file changed, 19 insertions(+), 16 deletions(-)
diff --git a/sound/pci/hda/hda_jack.c b/sound/pci/hda/hda_jack.c index 9746d73..376ce8f 100644 --- a/sound/pci/hda/hda_jack.c +++ b/sound/pci/hda/hda_jack.c @@ -105,6 +105,12 @@ snd_hda_jack_tbl_new(struct hda_codec *codec, hda_nid_t nid) return NULL; jack->nid = nid; jack->jack_dirty = 1;
- if (get_wcaps_type(get_wcaps(codec, nid)) == AC_WID_PIN) {
unsigned int def_conf = snd_hda_codec_get_pincfg(codec, nid);unsigned int conn = get_defcfg_connect(def_conf);if ((conn != AC_JACK_PORT_COMPLEX) || !is_jack_detectable(codec, nid))jack->phantom_jack = 1;- }
This doesn't look good. The pincfg isn't always reliable at this point. The pin connection check is used in add_jack_kctl() in the current code just because its only caller is snd_hda_jack_add_kctls(), which takes the pincfg explicitly. But snd_hda_jakc_tbl_new() itself is neutral about the pincfg.
And, another problem is that it'll result in a phantom jack secretly without adding a proper name suffix.
In anyway, for catching such a bug, maybe we should put a WARN_ON() at snd_hda_jack_detect_enable_callback() like the patch below.
Takashi
-- diff --git a/sound/pci/hda/hda_jack.c b/sound/pci/hda/hda_jack.c index 9746d73cec52..0645735e196d 100644 --- a/sound/pci/hda/hda_jack.c +++ b/sound/pci/hda/hda_jack.c @@ -225,6 +225,8 @@ int snd_hda_jack_detect_enable_callback(struct hda_codec *codec, hda_nid_t nid, return -ENOMEM; if (jack->jack_detect) return 0; /* already registered */ + if (WARN_ON(!is_jack_detectable(codec, nid))) + return 0; jack->jack_detect = 1; if (action) jack->action = action;