From 1c53e7253ed8769a00afa0f06777d731dbe1ba6f Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 2 May 2014 18:14:42 +0200 Subject: [PATCH] ALSA: usb-audio: Save mixer status only once at suspend The suspend callback of usb-audio driver may be called multiple times per suspend when multiple USB interfaces are bound to a single sound card instance. In such a case, it's superfluous to save the mixer values multiple times. This patch fixes it by checking the counter. Signed-off-by: Takashi Iwai --- sound/usb/card.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/sound/usb/card.c b/sound/usb/card.c index 893d5a1afc3c..e769d3977716 100644 --- a/sound/usb/card.c +++ b/sound/usb/card.c @@ -695,8 +695,9 @@ static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message) chip->autosuspended = 1; } - list_for_each_entry(mixer, &chip->mixer_list, list) - snd_usb_mixer_suspend(mixer); + if (chip->num_suspended_intf == 1) + list_for_each_entry(mixer, &chip->mixer_list, list) + snd_usb_mixer_suspend(mixer); return 0; } -- 2.20.1