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| author |   Alexander E. Patrakov <patrakov@ums.usu.ru> | 2007-10-31 11:40:09 -0300 |
|---|---|---|
| committer |   Mauro Carvalho Chehab <mchehab@infradead.org> | 2007-11-04 21:41:26 -0200 |
| commit | 32d111a9f0e6de901667612d1b0c46bbfd5d37cb (patch) | |
| tree | 32eaa18449c33f46dd99ed68354d1928eb176234 /drivers/media/video/saa7134/saa7134-alsa.c | |
| parent | V4L/DVB (6504): pvrusb2: Remove dead sysfs code (diff) | |
| download | linux-dev-32d111a9f0e6de901667612d1b0c46bbfd5d37cb.tar.xz linux-dev-32d111a9f0e6de901667612d1b0c46bbfd5d37cb.zip | |
V4L/DVB (6506): saa7134-alsa: Fix mmap support
Trent Piepho wrote:
> I do not think the saa7134-alsa driver supports mmap. The cx88-alsa driver
> also claimed to support mmap, but it never worked until I fixed it. It's
> pretty clear that the code in saa7134-alsa was based on the same code as
> cx88-alsa, so it's likely it has the same bug.
You are right. The patch below (based on your cx88 patch, but I don't
really understand it) fixes mmap support in saa7134-alsa for me.
Recording via mmap (arecord -M -f S16_LE -c 2 -r 32000 -D hw:1) didn't
work at all before, works now, tested for at least 20 minutes (but,
unfortunately, with one overrun at least 0.719 ms long).
Signed-off-by: Alexander E. Patrakov <patrakov@ums.usu.ru>
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Diffstat (limited to '')
| -rw-r--r-- | drivers/media/video/saa7134/saa7134-alsa.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/drivers/media/video/saa7134/saa7134-alsa.c b/drivers/media/video/saa7134/saa7134-alsa.c index c6f7279669c1..b9c5cf7dc849 100644 --- a/drivers/media/video/saa7134/saa7134-alsa.c +++ b/drivers/media/video/saa7134/saa7134-alsa.c @@ -543,8 +543,10 @@ static int snd_card_saa7134_hw_params(struct snd_pcm_substream * substream, V4L functions, and force ALSA to use that as the DMA area */ substream->runtime->dma_area = dev->dmasound.dma.vmalloc; + substream->runtime->dma_bytes = dev->dmasound.bufsize; + substream->runtime->dma_addr = 0; - return 1; + return 0; } @@ -652,6 +654,17 @@ static int snd_card_saa7134_capture_open(struct snd_pcm_substream * substream) } /* + * page callback (needed for mmap) + */ + +static struct page *snd_card_saa7134_page(struct snd_pcm_substream *substream, + unsigned long offset) +{ + void *pageptr = substream->runtime->dma_area + offset; + return vmalloc_to_page(pageptr); +} + +/* * ALSA capture callbacks definition */ @@ -664,6 +677,7 @@ static struct snd_pcm_ops snd_card_saa7134_capture_ops = { .prepare = snd_card_saa7134_capture_prepare, .trigger = snd_card_saa7134_capture_trigger, .pointer = snd_card_saa7134_capture_pointer, + .page = snd_card_saa7134_page, }; /* |