[alsa-devel] [PATCH] S3C64XX I2S: Added machine driver for WM8580

jassi brar jassisinghbrar at gmail.com
Thu Sep 17 13:35:56 CEST 2009


On Thu, Sep 17, 2009 at 8:02 PM, Mark Brown
<broonie at opensource.wolfsonmicro.com> wrote:
> On Thu, Sep 17, 2009 at 01:54:13PM +0900, jassi brar wrote:
>
>> +     /* Exceptions for this CPU-CODEC combination */
>> +     case 64000:
>> +             rfs = 384;
>> +             break;
>
> This needs to explain what the exceptions are for as well, otherwise
> anyone working with the code is going to have to work it out from
> scratch.
This note means stands for the forthcoming cases. The explanation is already
given above the switch.
/* Currently, WM8580 driver doesn't support PLL-out rates
 * other than those mentioned in Table-52 Page-58 of WM8580A
 * manual. Some of these unavailable rates include
 * {8000x256, 64000x256, 11025x256}Hz.
 * As a wayout, we rather change rfs to a value that results in
 * (params_rate(params) * rfs), and itself, acceptable to the both
 * the CODEC and the CPU.
 */
The rates 64000, 8000 and 11025 are thus 'exceptions'.

Infact, these were the real cases that I pointed during
MCLK/BCLK-RATIO discussions.
Currently, other cases work because 256fs RCLK is selected by default
and these three don't
because there is no way to indicate it to the CODEC driver.

>> +/* SMDK64xx Playback widgets */
>> +static const struct snd_soc_dapm_widget wm8580_dapm_widgets_pbk[] = {
>> +     SND_SOC_DAPM_HP("Front-L/R", NULL),
>> +     SND_SOC_DAPM_HP("Center/Sub", NULL),
>> +     SND_SOC_DAPM_HP("Rear-L/R", NULL),
>> +};
>
> All my previous comments about these and the way they're being
> configured still apply.
Once 6channel support is up, i will submit a patch to implement audio
routing options
using snd_soc_add_controls. Whereby user can set audio route on the device.
For now, as we have only 2channels enabled, i decided to enable only Front-L/R
and keep others disabled. Of the Mic and LineIn, we enable LineIn by
default. How is that?


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