diff options
author | Harald Welte <laforge@openmoko.org> | 2007-07-24 10:49:39 (GMT) |
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committer | Jaroslav Kysela <perex@perex.cz> | 2007-10-16 13:57:57 (GMT) |
commit | 646ab160ff5e672838209dbd679d50af63fbd366 (patch) | |
tree | b2661fdcd378aa090f6135ef0e2507da8110998e | |
parent | fca7f38892fa713d5221e26fd3ee57817b4bc031 (diff) | |
download | linux-646ab160ff5e672838209dbd679d50af63fbd366.tar.xz |
[ALSA] s3c24xx-pcm: fix hw_params dma handling
Since the PCM emulation can call multiple times to hw_setup(), but we
can only once allocate/request the DMA channel, we have to handle
this gracefully.
Signed-off-by: Harald Welte <laforge@openmoko.org>
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
-rw-r--r-- | sound/soc/s3c24xx/s3c24xx-pcm.c | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/sound/soc/s3c24xx/s3c24xx-pcm.c b/sound/soc/s3c24xx/s3c24xx-pcm.c index bfbdc3c..4107a87 100644 --- a/sound/soc/s3c24xx/s3c24xx-pcm.c +++ b/sound/soc/s3c24xx/s3c24xx-pcm.c @@ -158,18 +158,22 @@ static int s3c24xx_pcm_hw_params(struct snd_pcm_substream *substream, if (!dma) return 0; - /* prepare DMA */ - prtd->params = dma; + /* this may get called several times by oss emulation + * with different params -HW */ + if (prtd->params == NULL) { + /* prepare DMA */ + prtd->params = dma; - DBG("params %p, client %p, channel %d\n", prtd->params, - prtd->params->client, prtd->params->channel); + DBG("params %p, client %p, channel %d\n", prtd->params, + prtd->params->client, prtd->params->channel); - ret = s3c2410_dma_request(prtd->params->channel, - prtd->params->client, NULL); + ret = s3c2410_dma_request(prtd->params->channel, + prtd->params->client, NULL); - if (ret) { - DBG(KERN_ERR "failed to get dma channel\n"); - return ret; + if (ret) { + DBG(KERN_ERR "failed to get dma channel\n"); + return ret; + } } /* channel needs configuring for mem=>device, increment memory addr, |