From: Takashi Iwai Date: Thu, 25 Apr 2013 05:38:15 +0000 (+0200) Subject: ALSA: usb-audio: Fix autopm error during probing X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=60af3d037eb8c;p=openwrt%2Fstaging%2Fblogic.git ALSA: usb-audio: Fix autopm error during probing We've got strange errors in get_ctl_value() in mixer.c during probing, e.g. on Hercules RMX2 DJ Controller: ALSA mixer.c:352 cannot get ctl value: req = 0x83, wValue = 0x201, wIndex = 0xa00, type = 4 ALSA mixer.c:352 cannot get ctl value: req = 0x83, wValue = 0x200, wIndex = 0xa00, type = 4 .... It turned out that the culprit is autopm: snd_usb_autoresume() returns -ENODEV when called during card->probing = 1. Since the call itself during card->probing = 1 is valid, let's fix the return value of snd_usb_autoresume() as success. Reported-and-tested-by: Daniel Schürmann Cc: Signed-off-by: Takashi Iwai --- diff --git a/sound/usb/card.c b/sound/usb/card.c index 5254b18cedcd..1a033177b83f 100644 --- a/sound/usb/card.c +++ b/sound/usb/card.c @@ -631,7 +631,9 @@ int snd_usb_autoresume(struct snd_usb_audio *chip) int err = -ENODEV; down_read(&chip->shutdown_rwsem); - if (!chip->shutdown && !chip->probing) + if (chip->probing) + err = 0; + else if (!chip->shutdown) err = usb_autopm_get_interface(chip->pm_intf); up_read(&chip->shutdown_rwsem);