[PATCH 2/3] ALSA: usb-audio: Set sample rate for all sharing EPs on UAC1

[Takashi Iwai]

The UAC2/3 sample rate setup is based on the clock node, which is
usually shared in the interface, and can't be re-setup without
deselecting the interface once, and that's how the current code
behaves.  OTOH, the sample rate setup of UAC1 is per endpoint, hence
we basically need to call for each endpoint usage even if those share
the same interface.

This patch fixes the behavior of UAC1 to call always
snd_usb_init_sample_rate() in snd_usb_endpoint_configure().

Fixes: bf6313a0ff76 ("ALSA: usb-audio: Refactor endpoint management")
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
 sound/usb/endpoint.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index fe73fe3ff2bc..8e568823c992 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -1252,6 +1252,15 @@ int snd_usb_endpoint_configure(struct snd_usb_audio *chip,
 
 	/* If the interface has been already set up, just set EP parameters */
 	if (!ep->iface_ref->need_setup) {
+		/* sample rate setup of UAC1 is per endpoint, and we need
+		 * to update at each EP configuration
+		 */
+		if (ep->cur_audiofmt->protocol == UAC_VERSION_1) {
+			err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt,
+						       ep->cur_rate);
+			if (err < 0)
+				goto unlock;
+		}
 		err = snd_usb_endpoint_set_params(chip, ep);
 		if (err < 0)
 			goto unlock;
-- 
2.26.2