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ALSA: usb-audio: Fix init call orders for UAC1

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commit 5fadc941d0 upstream.

There have been reports of USB-audio driver spewing errors at the
probe time on a few devices like Jabra and Logitech.  The suggested
fix there couldn't be applied as is, unfortunately, because it'll
likely break other devices.

But, the patch suggested an interesting point: looking at the current
init code in stream.c, one may notice that it does initialize
differently from the device setup in endpoint.c.  Namely, for UAC1, we
should call snd_usb_init_pitch() and snd_usb_init_sample_rate() after
setting the interface, while the init sequence at parsing calls them
before setting the interface blindly.

This patch changes the init sequence at parsing for UAC1 (and other
devices that need a similar behavior) to be aligned with the rest of
the code, setting the interface at first.  And, this fixes the
long-standing problems on a few UAC1 devices like Jabra / Logitech,
as reported, too.

Reported-and-tested-by: Joakim Tjernlund <joakim.tjernlund@infinera.com>
Closes: https://lore.kernel.org/r/202bbbc0f51522e8545783c4c5577d12a8e2d56d.camel@infinera.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20230821111857.28926-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Takashi Iwai 2023-08-21 13:18:57 +02:00 committed by Greg Kroah-Hartman
parent f675a1ec3c
commit 1a29a82f8a
1 changed files with 10 additions and 1 deletions
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11
sound/usb/stream.c
View file

@ -1093,6 +1093,7 @@ static int __snd_usb_parse_audio_interface(struct snd_usb_audio *chip,
int i, altno, err, stream;
struct audioformat *fp = NULL;
struct snd_usb_power_domain *pd = NULL;
bool set_iface_first;
int num, protocol;
dev = chip->dev;
@ -1223,11 +1224,19 @@ static int __snd_usb_parse_audio_interface(struct snd_usb_audio *chip,
return err;
}
set_iface_first = false;
if (protocol == UAC_VERSION_1 ||
(chip->quirk_flags & QUIRK_FLAG_SET_IFACE_FIRST))
set_iface_first = true;
/* try to set the interface... */
usb_set_interface(chip->dev, iface_no, 0);
if (set_iface_first)
usb_set_interface(chip->dev, iface_no, altno);
snd_usb_init_pitch(chip, fp);
snd_usb_init_sample_rate(chip, fp, fp->rate_max);
usb_set_interface(chip->dev, iface_no, altno);
if (!set_iface_first)
usb_set_interface(chip->dev, iface_no, altno);
}
return 0;
}