From 34f3c89fda4fba9fe689db22253ca8db2f5e6386 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 15 Oct 2012 12:16:02 +0200 Subject: ALSA: usb-audio: Use rwsem for disconnect protection Replace mutex with rwsem for codec->shutdown protection so that concurrent accesses are allowed. Also add the protection to snd_usb_autosuspend() and snd_usb_autoresume(), too. Reported-by: Matthieu CASTET Cc: Signed-off-by: Takashi Iwai --- sound/usb/mixer.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'sound/usb/mixer.c') diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index c2ef11ccd66a..298070e8f2d4 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -292,7 +292,7 @@ static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request, int v err = snd_usb_autoresume(cval->mixer->chip); if (err < 0) return -EIO; - mutex_lock(&chip->shutdown_mutex); + down_read(&chip->shutdown_rwsem); while (timeout-- > 0) { if (chip->shutdown) break; @@ -310,7 +310,7 @@ static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request, int v err = -EINVAL; out: - mutex_unlock(&chip->shutdown_mutex); + up_read(&chip->shutdown_rwsem); snd_usb_autosuspend(cval->mixer->chip); return err; } @@ -337,7 +337,7 @@ static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int v if (ret) goto error; - mutex_lock(&chip->shutdown_mutex); + down_read(&chip->shutdown_rwsem); if (chip->shutdown) ret = -ENODEV; else { @@ -346,7 +346,7 @@ static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int v USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN, validx, idx, buf, size); } - mutex_unlock(&chip->shutdown_mutex); + up_read(&chip->shutdown_rwsem); snd_usb_autosuspend(chip); if (ret < 0) { @@ -453,7 +453,7 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval, err = snd_usb_autoresume(chip); if (err < 0) return -EIO; - mutex_lock(&chip->shutdown_mutex); + down_read(&chip->shutdown_rwsem); while (timeout-- > 0) { if (chip->shutdown) break; @@ -471,7 +471,7 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval, err = -EINVAL; out: - mutex_unlock(&chip->shutdown_mutex); + up_read(&chip->shutdown_rwsem); snd_usb_autosuspend(chip); return err; } -- cgit v1.2.3