ALSA: usb-audio: UAC2: support read-only freq control

Browse source

Some clocks might be read-only, e.g., external clocks (see also
UAC2 4.7.2.1).

In this case, setting the sample frequency will always fail
(even if the rate is equal to the current clock rate),
therefore do not write, but read the value and compare to the
requested rate.
If the clock is read only, avoid reading it twice.

If it doesn't match, return -ENXIO since the clock is invalid for
this configuration.

Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

...

This commit is contained in:

Eldad Zack 2013-04-03 23:18:58 +02:00 • committed by Takashi Iwai

parent 027bbc1546

commit 1dc669fed6

1 changed files with 26 additions and 11 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

37

sound/usb/clock.c

View file