From f1bc07af9a9edc5c1d4bdd971f7099316ed2e405 Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Mon, 7 Sep 2009 10:18:54 +0200 Subject: [PATCH] sound: oxygen: work around MCE when changing volume 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 Tested-by: Johann Messner Cc: Signed-off-by: Takashi Iwai --- sound/pci/oxygen/oxygen_io.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/sound/pci/oxygen/oxygen_io.c b/sound/pci/oxygen/oxygen_io.c index c1eb923f2ac9..09b2b2a36df5 100644 --- a/sound/pci/oxygen/oxygen_io.c +++ b/sound/pci/oxygen/oxygen_io.c @@ -215,17 +215,8 @@ EXPORT_SYMBOL(oxygen_write_spi); void oxygen_write_i2c(struct oxygen *chip, u8 device, u8 map, u8 data) { - unsigned long timeout; - /* should not need more than about 300 us */ - timeout = jiffies + msecs_to_jiffies(1); - do { - if (!(oxygen_read16(chip, OXYGEN_2WIRE_BUS_STATUS) - & OXYGEN_2WIRE_BUSY)) - break; - udelay(1); - cond_resched(); - } while (time_after_eq(timeout, jiffies)); + msleep(1); oxygen_write8(chip, OXYGEN_2WIRE_MAP, map); oxygen_write8(chip, OXYGEN_2WIRE_DATA, data); -- 2.39.2