[alsa-devel] [PATCH V2 01/10] ASoc: mxs: add mxs-pcm driver

[Dong Aisheng]

2011/7/14 Wolfram Sang <w.sang at pengutronix.de>:
>
>> +static struct snd_pcm_hardware snd_mxs_hardware = {
>> +     .info                   = SNDRV_PCM_INFO_MMAP |
>> +                               SNDRV_PCM_INFO_MMAP_VALID |
>> +                               SNDRV_PCM_INFO_PAUSE |
>> +                               SNDRV_PCM_INFO_RESUME |
>> +                               SNDRV_PCM_INFO_INTERLEAVED,
>> +     .formats                = SNDRV_PCM_FMTBIT_S16_LE |
>> +                               SNDRV_PCM_FMTBIT_S20_3LE |
>> +                               SNDRV_PCM_FMTBIT_S24_LE |
>> +                               SNDRV_PCM_FMTBIT_S32_LE,
>> +     .channels_min           = 2,
>> +     .channels_max           = 2,
>> +     .period_bytes_min       = 32,
>> +     .period_bytes_max       = 8192,
>> +     .periods_min            = 1,
>> +     .periods_max            = 255,
>
> When using madplay (for MP3) instead of aplay, I get
>
> [ 3310.010000] mxs-dma mxs-dma-apbx: maximum number of sg exceeded: 128 > 53
> [ 3310.020000] dma dma1chan4: cannot prepare slave dma
>
> So, the mxs-dma limit should be taken into account here.
I also have tried a lot on mp3 playing with madplay, however still have not
met this issue.
Can you tell how can i get the same mp3 as you played?
Maybe it helps me to reproduce this issue.
I will check it tomorrow.
Thanks for the reminder.

>> +     .buffer_bytes_max       = 64 * 1024,
>> +     .fifo_size              = 32,
>> +
>> +};