Commit e3ad86a8 authored by Rong Zhang's avatar Rong Zhang Committed by Takashi Iwai
Browse files

ALSA: usb-audio: Move volume control resolution check into a function 



get_min_max_with_quirks() is too lengthy and hard to read.

Move the volume control resolution check code into a function as it's
relatively self-contained.

Suggested-by: default avatarTakashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/87o6jsk3vs.wl-tiwai@suse.de


Signed-off-by: default avatarRong Zhang <i@rong.moe>
Link: https://patch.msgid.link/20260411-uac-sticky-mixer-v1-2-29d62717befd@rong.moe


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 4f55a85c

sound/usb/mixer.c

+39 −26
Original line number Diff line number Diff line
@@ -1232,6 +1232,38 @@ static void init_cur_mix_raw(struct usb_mixer_elem_info *cval, int ch, int idx) 
	snd_usb_set_cur_mix_value(cval, ch, idx, cval->min);

}



/*

 * Additional checks for the proper resolution

 *

 * Some devices report smaller resolutions than actually reacting.

 * They don't return errors but simply clip to the lower aligned value.

 */

static void check_volume_control_res(struct usb_mixer_elem_info *cval,

				     int channel, int saved)

{

	int last_valid_res = cval->res;

	int test, check;



	for (;;) {

		test = saved;

		if (test < cval->max)

			test += cval->res;

		else

			test -= cval->res;



		if (test < cval->min || test > cval->max ||

		    snd_usb_set_cur_mix_value(cval, channel, 0, test) ||

		    get_cur_mix_raw(cval, channel, &check)) {

			cval->res = last_valid_res;

			break;

		}

		if (test == check)

			break;



		cval->res *= 2;

	}

}



/*

 * retrieve the minimum and maximum values for the specified control

 */
@@ -1287,37 +1319,18 @@ static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval, 
		if (cval->res == 0)

			cval->res = 1;



		/* Additional checks for the proper resolution

		 *

		 * Some devices report smaller resolutions than actually

		 * reacting.  They don't return errors but simply clip

		 * to the lower aligned value.

		 */

		if (cval->min + cval->res < cval->max) {

			int last_valid_res = cval->res;

			int saved, test, check;

			int saved;



			if (get_cur_mix_raw(cval, minchn, &saved) < 0)

				goto no_res_check;

			for (;;) {

				test = saved;

				if (test < cval->max)

					test += cval->res;

				else

					test -= cval->res;

				if (test < cval->min || test > cval->max ||

				    snd_usb_set_cur_mix_value(cval, minchn, 0, test) ||

				    get_cur_mix_raw(cval, minchn, &check)) {

					cval->res = last_valid_res;

					break;

				}

				if (test == check)

					break;

				cval->res *= 2;

			}

				goto no_checks;



			check_volume_control_res(cval, minchn, saved);



			snd_usb_set_cur_mix_value(cval, minchn, 0, saved);

		}



no_res_check:

no_checks:

		cval->initialized = 1;

	}