lkml.org 
[lkml]   [2018]   [Aug]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 1/2] ASoC: Add driver for PROTO Audio CODEC (with a WM8731)
From
Date
On 29.08.2018 17:53, Mark Brown wrote:
> On Wed, Aug 29, 2018 at 05:47:26PM +0300, Codrin Ciubotariu wrote:
>
>> +static const unsigned int wm8731_rates_12288000[] = {
>> + 8000, 32000, 48000, 96000,
>> +};
>> +
>> +static struct snd_pcm_hw_constraint_list wm8731_constraints_12288000 = {
>> + .list = wm8731_rates_12288000,
>> + .count = ARRAY_SIZE(wm8731_rates_12288000),
>> +};
>> +
>> +static int snd_proto_startup(struct snd_pcm_substream *substream)
>> +{
>> + /* Setup constraints, because there is a 12.288 MHz XTAL on the board */
>> + snd_pcm_hw_constraint_list(substream->runtime, 0,
>> + SNDRV_PCM_HW_PARAM_RATE,
>> + &wm8731_constraints_12288000);
>> + return 0;
>> +}
>
> This bit is better added to the CODEC driver since it'll apply to any
> system where there's this clock rate (someone else could come in and add
> other rates, no need to do that yourself though it'd be nice of course).

I could do it.

>
> That also has the nice bonus that with that I think you'd be able to use
> the graph card rather than a custom driver?

The main reason for adding a custom driver and not using graph/simple
card is the snd_soc_dai_set_sysclk(codec_dai, WM8731_SYSCLK_XTAL,
XTAL_RATE, SND_SOC_CLOCK_IN) call. This
enables the oscillator found in the wm8731 codec. Since
WM8731_SYSCLK_XTAL is not 0, we can't use system-clock-frequency DT
property to set it.

Best regards,
Codrin

\
 
 \ /
  Last update: 2018-08-29 17:21    [W:0.073 / U:0.732 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site