[alsa-devel] [PATCH 2/2] ALSA sound driver for the AT73C213 DAC using Atmel SSC driver
tiwai at suse.de
Tue Jul 17 12:23:56 CEST 2007
At Tue, 17 Jul 2007 10:54:19 +0200,
Hans-Christian Egtvedt wrote:
> On Tue, 2007-07-17 at 10:48 +0200, Haavard Skinnemoen wrote:
> > On Tue, 17 Jul 2007 10:37:21 +0200
> > Hans-Christian Egtvedt <hcegtvedt at atmel.com> wrote:
> > > > > + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &at73c213_playback_ops);
> > > > > +
> > > > > + retval = snd_pcm_lib_preallocate_pages_for_all(chip->pcm,
> > > > > + SNDRV_DMA_TYPE_DEV,
> > > > > + snd_dma_continuous_data(GFP_KERNEL),
> > > > > + 64 * 1024, 64 * 1024);
> > > >
> > > > For SNDRV_DMA_TYPE_DEV, pass the struct device pointer of the device
> > > > to the third argument. Then the pre-allocator will allocate the
> > > > memory via dma_alloc_coherent() with the givn device. If it's not
> > > > appropriate, SNDRV_DMA_TYPE_CONTINUOUS type. Anyway,
> > > > snd_dma_continuous_data() is only for SNDRV_DMA_TYPE_CONTINUOUS.
> > >
> > > Ok, applied. Using &chip->spi->dev.
> > Not that I think it matters at the moment, but that's not entirely
> > correct. The memory is used for DMA transfers to the SSC controller,
> > not the SPI device, so you should pass the SSC's struct device here.
> > In other words, I think you should use &chip->ssc->pdev->dev.
> Hmm, my fault, applied.
> New patch attached.
The patch looks fine, but I suppose it's a post-2.6.23 material,
judging from the current situation. Is it OK?
Then I'll queue it soon after the merge window is closed, so that your
driver appears in the mm tree.
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