Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752833AbdHVTKO (ORCPT ); Tue, 22 Aug 2017 15:10:14 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:43554 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752797AbdHVTKN (ORCPT ); Tue, 22 Aug 2017 15:10:13 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Takashi Iwai Subject: [PATCH 4.4 09/20] ALSA: usb-audio: Add mute TLV for playback volumes on C-Media devices Date: Tue, 22 Aug 2017 12:09:52 -0700 Message-Id: <20170822190915.736582095@linuxfoundation.org> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20170822190915.345029476@linuxfoundation.org> References: <20170822190915.345029476@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1952 Lines: 65 4.4-stable 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 Signed-off-by: Greg Kroah-Hartman --- 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 @@ -541,6 +541,8 @@ int snd_usb_mixer_vol_tlv(struct snd_kco 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 @@ -64,6 +64,7 @@ struct usb_mixer_elem_info { int cached; int cache_val[MAX_CHANNELS]; u8 initialized; + u8 min_mute; void *private_data; }; --- a/sound/usb/mixer_quirks.c +++ b/sound/usb/mixer_quirks.c @@ -1873,6 +1873,12 @@ 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; } }