[alsa-devel] als4000: enable burst mode
tiwai at suse.de
Wed Aug 4 21:31:32 CEST 2010
At Wed, 4 Aug 2010 21:08:14 +0200,
Ondrej Zary wrote:
> On Wednesday 04 August 2010 07:43:44 Takashi Iwai wrote:
> > At Tue, 3 Aug 2010 23:57:05 +0200,
> > Ondrej Zary wrote:
> > > Enable burst mode to prevent dropouts during high PCI bus usage.
> > > The card is useless in X without this because of dropouts when anything
> > > moves on the screen (at least with PCI VGA card). Enabling this is also
> > > recommended by the datasheet (page 48).
> > >
> > > Signed-off-by: Ondrej Zary <linux at rainbow-software.org>
> > Applied now. Thanks.
> 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 v2 patch
> fixes this potential problem.
> Signed-off-by: Ondrej Zary <linux at rainbow-software.org>
As the previous patch was already applied, could you give the
> --- linux-2.6.35-rc2/sound/pci/als4000.c 2010-06-06 05:43:24.000000000 +0200
> +++ linux-2.6.35-rc3/sound/pci/als4000.c 2010-08-04 20:57:00.000000000 +0200
> @@ -763,9 +763,9 @@ static void snd_als4000_configure(struct
> /* SPECS_PAGE: 39 */
> for (i = ALS4K_GCR91_DMA0_ADDR; i <= ALS4K_GCR96_DMA3_MODE_COUNT; ++i)
> 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));
> + (snd_als4k_gcr_read(chip, ALS4K_GCR99_DMA_EMULATION_CTRL) & ~0x07) | 0x04);
> Ondrej Zary
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