[PATCH 5.10.y v1] ALSA: usb-audio: Evaluate packsize caps at the right place

[email protected]
Newsgroups gmane.linux.kernel.stable,gmane.linux.alsa.devel
Message-ID <[email protected]>
From: Takashi Iwai <[email protected]>

[ Upstream commit 52521e8398839105ef8eb22b3f0993f9b0d11a57 ]

We introduced the upper bound checks of the packet sizes by the
ep->maxframesize for avoiding the URB submission errors.  However, the
check was applied at an incorrect place in the function
snd_usb_endpoint_set_params() where ep->maxframesize isn't defined
yet; the value is defined at a bit later position.  So this ended up
with a failure at the first run while the second run works.

For fixing it, move the check at the correct place, right after the
calculation of ep->maxframesize in the same function.

Fixes: 7fe8dec3f628 ("ALSA: usb-audio: Cap the packet size pre-calculations")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=221292
Cc: <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Takashi Iwai <[email protected]>
[Pzqqt: Backport to 5.10]
Signed-off-by: Pzqqt <[email protected]>
---
 sound/usb/endpoint.c | 3 ---
 sound/usb/pcm.c      | 7 +++++++
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index 8e2b90cb5b95..21bcdc811a81 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -1099,9 +1099,6 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
 		return -EINVAL;
 	}
 
-	ep->packsize[0] = min(ep->packsize[0], ep->maxframesize);
-	ep->packsize[1] = min(ep->packsize[1], ep->maxframesize);
-
 	/* calculate the frequency in 16.16 format */
 	ep->freqm = ep->freqn;
 	ep->freqshift = INT_MIN;
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index f4494d054917..802ed1dbd23b 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -953,6 +953,13 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
 	subs->data_endpoint->curframesize =
 		bytes_to_frames(runtime, subs->data_endpoint->curpacksize);
 
+	subs->data_endpoint->packsize[0] = min(
+		subs->data_endpoint->packsize[0],
+		subs->data_endpoint->maxframesize);
+	subs->data_endpoint->packsize[1] = min(
+		subs->data_endpoint->packsize[1],
+		subs->data_endpoint->maxframesize);
+
 	/* reset the pointer */
 	subs->hwptr_done = 0;
 	subs->transfer_done = 0;
-- 
2.43.0
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.