[alsa-devel] [PATCH 9/10] ASoC: SAMSUNG: Add S/PDIF CPU driver

Seungwhan Youn claude.youn at gmail.com
Tue Oct 5 04:08:21 CEST 2010


Hi,

On Tue, Oct 5, 2010 at 7:02 AM, Mark Brown
<broonie at opensource.wolfsonmicro.com> wrote:
> On Mon, Oct 04, 2010 at 09:13:17PM +0900, Seungwhan Youn wrote:
>
>> +static int spdif_set_sysclk(struct snd_soc_dai *cpu_dai,
>> +                             int clk_id, unsigned int freq, int dir)
>> +{
>
> If you save the clock rate here...
>
>> +     case SND_SOC_SPDIF_MAIN_AUDIO_CLK:
>> +             switch (div) {
>> +             case 256:
>> +                     con |= CON_MCLKDIV_256FS;
>> +                     break;
>> +             case 384:
>> +                     con |= CON_MCLKDIV_384FS;
>> +                     break;
>> +             case 512:
>> +                     con |= CON_MCLKDIV_512FS;
>> +                     break;
>
> ...then you can calculate this dynamically at runtime in hw_params which
> makes life easier for users.

Yes, right. I'll fix this and resend a patch.
Actually the first time, I implemented like your opinion but I and
Jassi were afraid about S/PDIF use external clock rate.
But it's no matter that machine driver can give external clock rate also.

>
>> +/**
>> + * struct samsung_spdif_info - Samsung S/PDIF Controller information
>> + * @lock: Spin lock for S/PDIF.
>> + * @dev: The parent device passed to use from the probe.
>> + * @regs: The pointer to the device register block.
>> + * @pclk: The peri-clock pointer for spdif master operation.
>> + * @sclk: The source clock pointer for making sync signals.
>> + * @save_clkcon: Backup clkcon reg. in suspend.
>> + * @save_con: Backup con reg. in suspend.
>> + * @save_cstas: Backup cstas reg. in suspend.
>> + * @dma_playback: DMA information for playback channel.
>> + */
>> +struct samsung_spdif_info {
>> +     spinlock_t      lock;
>
> No need to have this in the headers.
>
>> +/* Registers */
>> +#define CLKCON                               0x00
>> +#define CON                          0x04
>> +#define BSTAS                                0x08
>
> These should all be namespaced or in the driver file to avoid collisoons
> with other things - even if only used in this driver things like CON are
> risky for collisions with normal kernel headers the driver needs.

Okay, I'll move these into driver file(and remove header file), and
resend patch few days later after listen other people's opinions.

Thanks,
Claude


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