From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754004AbdKFXZM (ORCPT ); Mon, 6 Nov 2017 18:25:12 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:51632 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753180AbdKFXXq (ORCPT ); Mon, 6 Nov 2017 18:23:46 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Takashi Iwai" Date: Mon, 06 Nov 2017 23:03:07 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 038/147] ALSA: usb-audio: Add mute TLV for playback volumes on C-Media devices In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.95-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Takashi Iwai commit 0f174b3525a43bd51f9397394763925e0ebe7bc7 upstream. C-Media devices (at least some models) mute the playback stream when volumes are set to the minimum value. But this isn't informed via TLV and the user-space, typically PulseAudio, gets confused as if it's still played in a low volume. This patch adds the new flag, min_mute, to struct usb_mixer_elem_info for indicating that the mixer element is with the minimum-mute volume. This flag is set for known C-Media devices in snd_usb_mixer_fu_apply_quirk() in turn. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196669 Signed-off-by: Takashi Iwai [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- sound/usb/mixer.c | 2 ++ sound/usb/mixer.h | 1 + sound/usb/mixer_quirks.c | 6 ++++++ 3 files changed, 9 insertions(+) --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -515,6 +515,8 @@ static int mixer_vol_tlv(struct snd_kcon if (size < sizeof(scale)) return -ENOMEM; + if (cval->min_mute) + scale[0] = SNDRV_CTL_TLVT_DB_MINMAX_MUTE; scale[2] = cval->dBmin; scale[3] = cval->dBmax; if (copy_to_user(_tlv, scale, sizeof(scale))) --- a/sound/usb/mixer.h +++ b/sound/usb/mixer.h @@ -52,6 +52,7 @@ struct usb_mixer_elem_info { int cached; int cache_val[MAX_CHANNELS]; u8 initialized; + u8 min_mute; }; int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif, --- a/sound/usb/mixer_quirks.c +++ b/sound/usb/mixer_quirks.c @@ -726,6 +726,12 @@ void snd_usb_mixer_fu_apply_quirk(struct if (unitid == 7 && cval->control == UAC_FU_VOLUME) snd_dragonfly_quirk_db_scale(mixer, cval, kctl); break; + /* lowest playback value is muted on C-Media devices */ + case USB_ID(0x0d8c, 0x000c): + case USB_ID(0x0d8c, 0x0014): + if (strstr(kctl->id.name, "Playback")) + cval->min_mute = 1; + break; } }