[alsa-devel] [PATCH 1/2] ASoC: topology: Rename clock_gated to clock_cont in snd_soc_tplg_hw_config

[Kirill Marinushkin]

On 02/19/18 07:47, Takashi Sakamoto wrote:
> Hi,
>
> On Feb 19 2018 15:05, Kirill Marinushkin wrote:
>> In kernel `soc-dai.h`, DAI clock gating is defined as following:
>>
>> ~~~~
>> \#define SND_SOC_DAIFMT_CONT        (1 << 4) /* continuous clock */
>> \#define SND_SOC_DAIFMT_GATED        (0 << 4) /* clock is gated */
>> ~~~~
>>
>> Therefore, the corresponding field of struct snd_soc_tplg_hw_config should
>> be inverted compared to the current logic:
>>
>> clock_count = 1 => SND_SOC_DAIFMT_CONT
>> clock_count = 0 => SND_SOC_DAIFMT_GATED
>>
>> Signed-off-by: Kirill Marinushkin <k.marinushkin at gmail.com>
>> Cc: Jaroslav Kysela <perex at perex.cz>
>> Cc: Takashi Iwai <tiwai at suse.com>
>> Cc: alsa-devel at alsa-project.org
>> Cc: linux-kernel at vger.kernel.org
>> ---
>>   include/uapi/sound/asoc.h | 4 +++-
>>   1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/uapi/sound/asoc.h b/include/uapi/sound/asoc.h
>> index 69c37ecbff7e..10188850dede 100644
>> --- a/include/uapi/sound/asoc.h
>> +++ b/include/uapi/sound/asoc.h
>> @@ -312,7 +312,9 @@ struct snd_soc_tplg_hw_config {
>>       __le32 size;            /* in bytes of this structure */
>>       __le32 id;        /* unique ID - - used to match */
>>       __le32 fmt;        /* SND_SOC_DAI_FORMAT_ format value */
>> -    __u8 clock_gated;    /* 1 if clock can be gated to save power */
>> +    __u8 clock_cont;    /* 1 if clock is continuous, and can not be
>> +                 * gated to save power
>> +                 */
>>       __u8 invert_bclk;    /* 1 for inverted BCLK, 0 for normal */
>>       __u8 invert_fsync;    /* 1 for inverted frame clock, 0 for normal */
>>       __u8 bclk_master;    /* 1 for master of BCLK, 0 for slave */
>
> This structure was added at a commit 676c6b5208f7 ('ASoC: topology: ABI - Update physical DAI link configuration for version 5') in a development period for v4.10.
>
> This file is a part of UAPI, thus this structure has already been exposed to application developers. Any change can break userspace applications in a point of backward compatibility for this subsystem.
>
> It's better for you to investigate another solution for your two patches[1][2].
>
>
> [1] [alsa-devel] [PATCH 1/2] ASoC: topology: Rename clock_gated to clock_cont in snd_soc_tplg_hw_config
> http://mailman.alsa-project.org/pipermail/alsa-devel/2018-February/132258.html
> [2] [alsa-devel] [PATCH 2/2] ASoC: topology: Add missing clock gating parameter when parsing hw_configs
> http://mailman.alsa-project.org/pipermail/alsa-devel/2018-February/132259.html
>
>
> Regards
>
> Takashi Sakamoto

Hello Takashi Sakamoto,

I will propose a backwards-compatible solution as a PATCH v2.

Best Regards,
Kirill