Commit 481f17c4 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: usb-audio: Handle error for the current selector gracefully 

Currently we bail out when the device returns an error or an invalid
value for the current clock selector value via
uac_clock_selector_get_val().  But it's possible that the device is
really uninitialized and waits for the setup of the proper route at
first.

For handling such a case, this patch lets the driver dealing with the
error or the invalid error more gracefully, choosing the clock source
automatically instead.

Link: https://lore.kernel.org/r/20210518152112.8016-3-tiwai@suse.de


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 9ec73005

sound/usb/clock.c

+10 −3
Original line number Diff line number Diff line
@@ -299,8 +299,11 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip, 
		/* the entity ID we are looking for is a selector.

		 * find out what it currently selects */

		ret = uac_clock_selector_get_val(chip, clock_id);

		if (ret < 0)

		if (ret < 0) {

			if (!chip->autoclock)

				return ret;

			goto find_others;

		}



		/* Selector values are one-based */
@@ -309,7 +312,10 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip, 
				"%s(): selector reported illegal value, id %d, ret %d\n",

				__func__, clock_id, ret);



			if (!chip->autoclock)

				return -EINVAL;

			ret = 0;

			goto find_others;

		}



	find_source:
@@ -326,6 +332,7 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip, 
		if (!validate || ret > 0 || !chip->autoclock)

			return ret;



	find_others:

		/* The current clock source is invalid, try others. */

		for (i = 1; i <= pins; i++) {

			if (i == cur)