sound: oxygen: work around MCE when changing volume
commitdb15c341d2cc6d162e3b7aa4c72bd49cf03dd30f
authorClemens Ladisch <clemens@ladisch.de>
Mon, 7 Sep 2009 08:18:54 +0000 (7 10:18 +0200)
committerGreg Kroah-Hartman <gregkh@suse.de>
Thu, 24 Sep 2009 15:43:59 +0000 (24 08:43 -0700)
treec0c0900e8c83af97df2465da624ee5a56b1be7dc
parentcaa4489e9a48492d336e57765eea50223ee71d69
sound: oxygen: work around MCE when changing volume

commit f1bc07af9a9edc5c1d4bdd971f7099316ed2e405 upstream.

When the volume is changed continuously (e.g., when the user drags a
volume slider with the mouse), the driver does lots of I2C writes.
Apparently, the sound chip can get confused when we poll the I2C status
register too much, and fails to complete a read from it.  On the PCI-E
models, the PCI-E/PCI bridge gets upset by this and generates a machine
check exception.

To avoid this, this patch replaces the polling with an unconditional
wait that is guaranteed to be long enough.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Johann Messner <johann.messner at jku.at>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sound/pci/oxygen/oxygen_io.c