ALSA: als4000: Fix potentially invalid DMA mode setup
Ondrej Zary [Wed, 4 Aug 2010 19:56:44 +0000 (21:56 +0200)]
My previous patch assumed that the DMA mode (represented by 3 lowest bits of
ALS4K_GCR99_DMA_EMULATION_CTRL register) is set to the default value 0. If
that's not the case, it might result in invalid mode to be set.
This patch fixes this potential problem.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/als4000.c

index 036a9ba..0e247cb 100644 (file)
@@ -765,7 +765,7 @@ static void snd_als4000_configure(struct snd_sb *chip)
                snd_als4k_gcr_write(chip, i, 0);
        /* enable burst mode to prevent dropouts during high PCI bus usage */
        snd_als4k_gcr_write(chip, ALS4K_GCR99_DMA_EMULATION_CTRL,
-               snd_als4k_gcr_read(chip, ALS4K_GCR99_DMA_EMULATION_CTRL) | 0x04);
+               (snd_als4k_gcr_read(chip, ALS4K_GCR99_DMA_EMULATION_CTRL) & ~0x07) | 0x04);
        spin_unlock_irq(&chip->reg_lock);
 }