diff options
author | Alison Wang <b18965@freescale.com> | 2014-09-29 09:29:46 (GMT) |
---|---|---|
committer | Matthew Weigel <Matthew.Weigel@freescale.com> | 2014-12-11 18:38:39 (GMT) |
commit | f911217e6edd48de4277eec2f112449d61fe710e (patch) | |
tree | 138c09a2cdcc706f25ac60d5992f98a93ee79616 /sound/core | |
parent | 0ec580b6a604a4fcfd65c3515459def643c8517a (diff) | |
download | linux-fsl-qoriq-f911217e6edd48de4277eec2f112449d61fe710e.tar.xz |
ls102xa: audio: Workaround for SAI data transfer endian issue
Transmit Data Register(TDR) used as the destination address
of EDMA transaction is in big-endian mode. The audio data in
memory and EDMA transaction are in little-endian mode. For
S16_LE format data, a workaround is to swap the original 16-bit
data, and then write into the higher 16 bit of TDR.
Signed-off-by: Alison Wang <alison.wang@freescale.com>
Change-Id: Ib15832743e9a4c69792f2dad4cb00fbbc1d2daaa
Reviewed-on: http://git.am.freescale.net:8181/21063
Tested-by: Review Code-CDREVIEW <CDREVIEW@freescale.com>
Reviewed-by: Jingchang Lu <jingchang.lu@freescale.com>
Reviewed-by: Zhengxiong Jin <Jason.Jin@freescale.com>
Diffstat (limited to 'sound/core')
-rw-r--r-- | sound/core/pcm_lib.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index a210467..f1fe6e6 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -1962,6 +1962,9 @@ static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream, struct snd_pcm_runtime *runtime = substream->runtime; int err; char __user *buf = (char __user *) data + frames_to_bytes(runtime, off); + int i; + char tmp; + if (substream->ops->copy) { if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0) return err; @@ -1969,6 +1972,22 @@ static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream, char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff); if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames))) return -EFAULT; + + if (substream->data_swapped) { + switch (runtime->format) { + case SNDRV_PCM_FORMAT_S16_LE: + for (i = 0; + i < frames_to_bytes(runtime, frames); + i = i + 2) { + tmp = *(hwbuf + i); + *(hwbuf + i) = *(hwbuf + i + 1); + *(hwbuf + i + 1) = tmp; + } + break; + default: + return -EINVAL; + } + } } return 0; } @@ -2184,11 +2203,30 @@ static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream, struct snd_pcm_runtime *runtime = substream->runtime; int err; char __user *buf = (char __user *) data + frames_to_bytes(runtime, off); + int i; + char tmp; + if (substream->ops->copy) { if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0) return err; } else { char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff); + if (substream->data_swapped) { + switch (runtime->format) { + case SNDRV_PCM_FORMAT_S16_LE: + for (i = 0; + i < frames_to_bytes(runtime, frames); + i = i + 2) { + tmp = *(hwbuf + i); + *(hwbuf + i) = *(hwbuf + i + 1); + *(hwbuf + i + 1) = tmp; + } + break; + default: + return -EINVAL; + } + } + if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames))) return -EFAULT; } |