From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gabriele Mazzotta Subject: Re: Pop noise on startup when headphones are plugged in (Dell XPS13 9333) Date: Sat, 25 Apr 2015 13:51:33 +0200 Message-ID: <2264204.W7vnUSq2WO@xps13> References: <23057263.IjMh4t6SYF@xps13> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wg0-f42.google.com (mail-wg0-f42.google.com [74.125.82.42]) by alsa0.perex.cz (Postfix) with ESMTP id 568142614FF for ; Sat, 25 Apr 2015 13:51:35 +0200 (CEST) Received: by wgen6 with SMTP id n6so74139514wge.3 for ; Sat, 25 Apr 2015 04:51:35 -0700 (PDT) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Takashi Iwai Cc: Raymond Yau , ALSA Development Mailing List List-Id: alsa-devel@alsa-project.org On Friday 24 April 2015 17:34:57 Takashi Iwai wrote: > At Fri, 24 Apr 2015 17:14:24 +0200, > Gabriele Mazzotta wrote: > > > > 2015-04-24 8:13 GMT+02:00 Takashi Iwai : > > > At Thu, 23 Apr 2015 21:12:50 +0200, > > > Gabriele Mazzotta wrote: > > >> > > >> On Sunday 19 April 2015 19:26:58 Gabriele Mazzotta wrote: > > >> > Hi, > > >> > > > >> > I've recently found that commit a551d91473 ("ALSA: hda - Use regmap for > > >> > command verb caches, too") is somehow causing a pop noise on startup > > >> > when headphones are plugged in, but I couldn't figure out the exact > > >> > cause. Was this observed on other systems (mine is a Dell XPS13 9333, > > >> > Realtek ALC3661)? Does anyone have any idea of what the cause might be? > > >> > > >> Hi, > > >> > > >> I don't know why a551d91473 caused the issue, but I found the real > > >> cause of problem. > > >> > > >> On init, create_input_ctls() sets the vref of nid 0x19 to 80 (as > > >> returned by snd_hda_get_default_vref()), but it should be set to HIZ. > > >> This is not so different from the issue addressed by f38663ab5c > > >> ("ALSA: hda - Set internal mic as default input source on Dell XPS 13 9333"). > > >> > > >> I made a patch to prevent this from happening. > > >> > > >> Setting the vref is not necessary since alc_update_headset_mode() will > > >> take care of it. > > >> > > >> Should I maybe add a new flag instead of using suppress_hp_mic_detect? > > > > > > Yeah, that's better. Although the flag is currently unused, it's > > > provided for a different purpose (to skip the headphone mic detection; > > > which is different from "headset" mic). > > > > > > I wonder, though, whether the patch below improves anything. > > > A similar patch was in the development series in the past, but I had > > > to drop it because it caused behavior error. But now I tried again, > > > and it seems working. > > > > > > > > > Takashi > > > > The patch did no harm, but didn't solve the problem. > > OK, so the problem doesn't seem relevant with the runtime PM, which > was the usual suspect. > > My patch should reduce the actual verb writes, so it would be nice to > have even if it doesn't fix your problem. But maybe I'll postpone it > as a 4.2 material. > > > thanks, > > Takashi Hi, I think this the patch here below is simpler than the other I sent. snd_hda_get_default_vref() guesses the vref input pins. We know that some of these are for headphones/headset mics, so we could set the vref to HIZ for these. Are there systems that would misbehave with this change? Gabriele --- diff --git a/sound/pci/hda/hda_generic.c b/sound/pci/hda/hda_generic.c index 3d2597b..081db8b 100644 --- a/sound/pci/hda/hda_generic.c +++ b/sound/pci/hda/hda_generic.c @@ -3257,7 +3257,9 @@ static int create_input_ctls(struct hda_codec *codec) continue; val = PIN_IN; - if (cfg->inputs[i].type == AUTO_PIN_MIC) + if (cfg->inputs[i].type == AUTO_PIN_MIC && + !cfg->inputs[i].is_headset_mic && + !cfg->inputs[i].is_headphone_mic) val |= snd_hda_get_default_vref(codec, pin); if (pin != spec->hp_mic_pin) set_pin_target(codec, pin, val, false);