diff mbox series

ALSA: usb-audio: Explicitly set up the clock selector

Message ID 20210413084152.32325-1-tiwai@suse.de (mailing list archive)
State Accepted
Commit d2e8f641257d0d3af6e45d6ac2d6f9d56b8ea964
Headers show
Series ALSA: usb-audio: Explicitly set up the clock selector | expand

Commit Message

Takashi Iwai April 13, 2021, 8:41 a.m. UTC
In the current code, we have some assumption that the audio clock
selector has been set up implicitly and don't want to touch it unless
it's really needed for the fallback autoclock setup.  This works for
most devices but some seem having a problem.  Partially this was
covered for the devices with a single connector at the initialization
phase (commit 086b957cc17f "ALSA: usb-audio: Skip the clock selector
inquiry for single connections"), but also there are cases where the
wrong clock set up is kept silently.  The latter seems to be the cause
of the noises on Behringer devices.

In this patch, we explicitly set up the audio clock selector whenever
the appropriate node is found.

Reported-by: Geraldo Nascimento <geraldogabriel@gmail.com>
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199327
Link: https://lore.kernel.org/r/CAEsQvcvF7LnO8PxyyCxuRCx=7jNeSCvFAd-+dE0g_rd1rOxxdw@mail.gmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 sound/usb/clock.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

Comments

Geraldo Nascimento April 14, 2021, 6:19 p.m. UTC | #1
Thanks, Dr. Iwai!

I haven't tested the finalized patch yet, but I'll give it a shot on top of
5.12-rc7. Should be OK, nevertheless thorough testing is always a good idea.

Regards,
Geraldo

Em Ter, 13 de abr de 2021 05:41, Takashi Iwai <tiwai@suse.de> escreveu:

> In the current code, we have some assumption that the audio clock
> selector has been set up implicitly and don't want to touch it unless
> it's really needed for the fallback autoclock setup.  This works for
> most devices but some seem having a problem.  Partially this was
> covered for the devices with a single connector at the initialization
> phase (commit 086b957cc17f "ALSA: usb-audio: Skip the clock selector
> inquiry for single connections"), but also there are cases where the
> wrong clock set up is kept silently.  The latter seems to be the cause
> of the noises on Behringer devices.
>
> In this patch, we explicitly set up the audio clock selector whenever
> the appropriate node is found.
>
> Reported-by: Geraldo Nascimento <geraldogabriel@gmail.com>
> BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199327
> Link:
> https://lore.kernel.org/r/CAEsQvcvF7LnO8PxyyCxuRCx=7jNeSCvFAd-+dE0g_rd1rOxxdw@mail.gmail.com
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Takashi Iwai <tiwai@suse.de>
> ---
>  sound/usb/clock.c | 18 ++++++++++++++----
>  1 file changed, 14 insertions(+), 4 deletions(-)
>
> diff --git a/sound/usb/clock.c b/sound/usb/clock.c
> index a746802d0ac3..17bbde73d4d1 100644
> --- a/sound/usb/clock.c
> +++ b/sound/usb/clock.c
> @@ -296,7 +296,7 @@ static int __uac_clock_find_source(struct
> snd_usb_audio *chip,
>
>         selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
>         if (selector) {
> -               int ret, i, cur;
> +               int ret, i, cur, err;
>
>                 if (selector->bNrInPins == 1) {
>                         ret = 1;
> @@ -324,13 +324,17 @@ static int __uac_clock_find_source(struct
> snd_usb_audio *chip,
>                 ret = __uac_clock_find_source(chip, fmt,
>                                               selector->baCSourceID[ret -
> 1],
>                                               visited, validate);
> +               if (ret > 0) {
> +                       err = uac_clock_selector_set_val(chip, entity_id,
> cur);
> +                       if (err < 0)
> +                               return err;
> +               }
> +
>                 if (!validate || ret > 0 || !chip->autoclock)
>                         return ret;
>
>                 /* The current clock source is invalid, try others. */
>                 for (i = 1; i <= selector->bNrInPins; i++) {
> -                       int err;
> -
>                         if (i == cur)
>                                 continue;
>
> @@ -396,7 +400,7 @@ static int __uac3_clock_find_source(struct
> snd_usb_audio *chip,
>
>         selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf,
> entity_id);
>         if (selector) {
> -               int ret, i, cur;
> +               int ret, i, cur, err;
>
>                 /* the entity ID we are looking for is a selector.
>                  * find out what it currently selects */
> @@ -418,6 +422,12 @@ static int __uac3_clock_find_source(struct
> snd_usb_audio *chip,
>                 ret = __uac3_clock_find_source(chip, fmt,
>                                                selector->baCSourceID[ret -
> 1],
>                                                visited, validate);
> +               if (ret > 0) {
> +                       err = uac_clock_selector_set_val(chip, entity_id,
> cur);
> +                       if (err < 0)
> +                               return err;
> +               }
> +
>                 if (!validate || ret > 0 || !chip->autoclock)
>                         return ret;
>
> --
> 2.26.2
>
>
diff mbox series

Patch

diff --git a/sound/usb/clock.c b/sound/usb/clock.c
index a746802d0ac3..17bbde73d4d1 100644
--- a/sound/usb/clock.c
+++ b/sound/usb/clock.c
@@ -296,7 +296,7 @@  static int __uac_clock_find_source(struct snd_usb_audio *chip,
 
 	selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
 	if (selector) {
-		int ret, i, cur;
+		int ret, i, cur, err;
 
 		if (selector->bNrInPins == 1) {
 			ret = 1;
@@ -324,13 +324,17 @@  static int __uac_clock_find_source(struct snd_usb_audio *chip,
 		ret = __uac_clock_find_source(chip, fmt,
 					      selector->baCSourceID[ret - 1],
 					      visited, validate);
+		if (ret > 0) {
+			err = uac_clock_selector_set_val(chip, entity_id, cur);
+			if (err < 0)
+				return err;
+		}
+
 		if (!validate || ret > 0 || !chip->autoclock)
 			return ret;
 
 		/* The current clock source is invalid, try others. */
 		for (i = 1; i <= selector->bNrInPins; i++) {
-			int err;
-
 			if (i == cur)
 				continue;
 
@@ -396,7 +400,7 @@  static int __uac3_clock_find_source(struct snd_usb_audio *chip,
 
 	selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id);
 	if (selector) {
-		int ret, i, cur;
+		int ret, i, cur, err;
 
 		/* the entity ID we are looking for is a selector.
 		 * find out what it currently selects */
@@ -418,6 +422,12 @@  static int __uac3_clock_find_source(struct snd_usb_audio *chip,
 		ret = __uac3_clock_find_source(chip, fmt,
 					       selector->baCSourceID[ret - 1],
 					       visited, validate);
+		if (ret > 0) {
+			err = uac_clock_selector_set_val(chip, entity_id, cur);
+			if (err < 0)
+				return err;
+		}
+
 		if (!validate || ret > 0 || !chip->autoclock)
 			return ret;