ALSA: usb-audio: Add PM guard to Studio 1810c controls

The Studio 1810c control callbacks issue vendor transfers without
preventing runtime suspend or disconnect. A transfer attempted after
runtime suspend can fail because the USB device cannot accept
submissions.

Take snd_usb_lock before the driver data and USB mutexes in both
callbacks. This resumes the device before either the state read or
control write. It also prevents disconnect cleanup from racing the
complete operation.

Assisted-by: Codex:gpt-5.6-sol
Signed-off-by: Will Porter <mrwillporter@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260827232143.149197-2-mrwillporter@gmail.com
This commit is contained in:
Will Porter 2026-08-27 18:21:38 -05:00 committed by Takashi Iwai
parent cee9395acd
commit 077304dfa7

View File

@ -474,6 +474,10 @@ snd_s1810c_switch_get(struct snd_kcontrol *kctl,
u32 state = 0;
int ret;
CLASS(snd_usb_lock, pm)(mixer->chip);
if (pm.err < 0)
return -EIO;
guard(mutex)(&private->data_mutex);
ret = snd_s1810c_get_switch_state(mixer, kctl, &state);
if (ret < 0)
@ -504,6 +508,10 @@ snd_s1810c_switch_set(struct snd_kcontrol *kctl,
u32 newval = 0;
int ret = 0;
CLASS(snd_usb_lock, pm)(mixer->chip);
if (pm.err < 0)
return -EIO;
guard(mutex)(&private->data_mutex);
ret = snd_s1810c_get_switch_state(mixer, kctl, &curval);
if (ret < 0)