[PATCH 01/13] ALSA: pcm: add more sample rate definitions
Amadeusz Sławiński
amadeuszx.slawinski at linux.intel.com
Wed Sep 11 06:37:44 PDT 2024
On 9/11/2024 2:42 PM, Takashi Iwai wrote:
> On Wed, 11 Sep 2024 12:58:53 +0200,
> Jaroslav Kysela wrote:
>>
>> On 11. 09. 24 12:51, Takashi Iwai wrote:
>>> On Wed, 11 Sep 2024 12:33:01 +0200,
>>> Péter Ujfalusi wrote:
>>>>
>>>> On 11/09/2024 12:21, Takashi Iwai wrote:
>>>>>> Wondering if this is backwards compatible with the alsa-lib definitions,
>>>>>> specifically the topology parts which did unfortunately have a list of
>>>>>> rates that will map to a different index now:
>>>>>>
>>>>>>
>>>>>> typedef enum _snd_pcm_rates {
>>>>>> SND_PCM_RATE_UNKNOWN = -1,
>>>>>> SND_PCM_RATE_5512 = 0,
>>>>>> SND_PCM_RATE_8000,
>>>>>> SND_PCM_RATE_11025,
>>>>>> SND_PCM_RATE_16000,
>>>>>> SND_PCM_RATE_22050,
>>>>>> SND_PCM_RATE_32000,
>>>>>> SND_PCM_RATE_44100,
>>>>>> SND_PCM_RATE_48000,
>>>>>> SND_PCM_RATE_64000,
>>>>>> SND_PCM_RATE_88200,
>>>>>> SND_PCM_RATE_96000,
>>>>>> SND_PCM_RATE_176400,
>>>>>> SND_PCM_RATE_192000,
>>>>>> SND_PCM_RATE_CONTINUOUS = 30,
>>>>>> SND_PCM_RATE_KNOT = 31,
>>>>>> SND_PCM_RATE_LAST = SND_PCM_RATE_KNOT,
>>>>>> } snd_pcm_rates_t;
>>>>>
>>>>> As far as I understand correctly, those rate bits used for topology
>>>>> are independent from the bits used for PCM core, although it used to
>>>>> be the same. Maybe better to rename (such as SND_TPLG_RATE_*) so that
>>>>> it's clearer only for topology stuff.
>>>>
>>>> Even if we rename these in alsa-lib we will need translation from
>>>> SND_TPLG_RATE_ to SND_PCM_RATE_ in kernel likely?
>>>>
>>>> The topology files are out there and this is an ABI...
>>>>
>>>>> But it'd be better if anyone can double-check.
>>>>
>>>> Since the kernel just copies the rates bitfield, any rate above 11025
>>>> will be misaligned and result broken setup.
>>>
>>> Yep, I noticed it now, too.
>>>
>>> Below is the fix patch, totally untested.
>>> It'd be appreciated if anyone can test it quickly.
>>>
>>>
>>> thanks,
>>>
>>> Takashi
>>>
>>> -- 8< --
>>> From: Takashi Iwai <tiwai at suse.de>
>>> Subject: [PATCH] ALSA: pcm: Fix breakage of PCM rates used for topology
>>>
>>> It turned out that the topology ABI takes the standard PCM rate bits
>>> as is, and it means that the recent change of the PCM rate bits would
>>> lead to the inconsistent rate values used for topology.
>>>
>>> This patch reverts the original PCM rate bit definitions while adding
>>> the new rates to the extended bits instead. This needed the change of
>>> snd_pcm_known_rates, too. And this also required to fix the handling
>>> in snd_pcm_hw_limit_rates() that blindly assumed that the list is
>>> sorted while it became unsorted now.
>>>
>>> Fixes: 090624b7dc83 ("ALSA: pcm: add more sample rate definitions")
>>> Signed-off-by: Takashi Iwai <tiwai at suse.de>
>>
>> This looks fine. But the topology rate bits should not depend on those
>> bits. It's a bit pitty that the standard PCM ABI does not use those
>> bits for user space and we are doing this change just for topology
>> ABI.
>
> Yeah, and theoretically it's possible to fix in topology side, but
> it'll be more cumbersome.
>
> Although it's not really a part of PCM ABI, I believe we should move
> the PCM rate bit definitions to uapi, for showing that it's set in
> stone. Something like below.
>
>
> Takashi
>
> -- 8< --
> From: Takashi Iwai <tiwai at suse.de>
> Subject: [PATCH] ALSA: pcm: Move standard rate bit definitions into uapi
>
> Since the standard PCM rate bits are used for the topology ABI, it's a
> part of public ABI that must not be changed. Move the definitions
> into uapi to indicate it more clearly.
>
> Signed-off-by: Takashi Iwai <tiwai at suse.de>
> ---
> include/sound/pcm.h | 26 --------------------------
> include/uapi/sound/asound.h | 26 ++++++++++++++++++++++++++
> 2 files changed, 26 insertions(+), 26 deletions(-)
>
> diff --git a/include/sound/pcm.h b/include/sound/pcm.h
> index 824216799070..f28f6d6ac996 100644
> --- a/include/sound/pcm.h
> +++ b/include/sound/pcm.h
> @@ -105,32 +105,6 @@ struct snd_pcm_ops {
>
> #define SNDRV_PCM_POS_XRUN ((snd_pcm_uframes_t)-1)
>
> -/* If you change this don't forget to change rates[] table in pcm_native.c */
> -#define SNDRV_PCM_RATE_5512 (1U<<0) /* 5512Hz */
> -#define SNDRV_PCM_RATE_8000 (1U<<1) /* 8000Hz */
> -#define SNDRV_PCM_RATE_11025 (1U<<2) /* 11025Hz */
> -#define SNDRV_PCM_RATE_16000 (1U<<3) /* 16000Hz */
> -#define SNDRV_PCM_RATE_22050 (1U<<4) /* 22050Hz */
> -#define SNDRV_PCM_RATE_32000 (1U<<5) /* 32000Hz */
> -#define SNDRV_PCM_RATE_44100 (1U<<6) /* 44100Hz */
> -#define SNDRV_PCM_RATE_48000 (1U<<7) /* 48000Hz */
> -#define SNDRV_PCM_RATE_64000 (1U<<8) /* 64000Hz */
> -#define SNDRV_PCM_RATE_88200 (1U<<9) /* 88200Hz */
> -#define SNDRV_PCM_RATE_96000 (1U<<10) /* 96000Hz */
> -#define SNDRV_PCM_RATE_176400 (1U<<11) /* 176400Hz */
> -#define SNDRV_PCM_RATE_192000 (1U<<12) /* 192000Hz */
> -#define SNDRV_PCM_RATE_352800 (1U<<13) /* 352800Hz */
> -#define SNDRV_PCM_RATE_384000 (1U<<14) /* 384000Hz */
> -#define SNDRV_PCM_RATE_705600 (1U<<15) /* 705600Hz */
> -#define SNDRV_PCM_RATE_768000 (1U<<16) /* 768000Hz */
> -/* extended rates */
> -#define SNDRV_PCM_RATE_12000 (1U<<17) /* 12000Hz */
> -#define SNDRV_PCM_RATE_24000 (1U<<18) /* 24000Hz */
> -#define SNDRV_PCM_RATE_128000 (1U<<19) /* 128000Hz */
> -
> -#define SNDRV_PCM_RATE_CONTINUOUS (1U<<30) /* continuous range */
> -#define SNDRV_PCM_RATE_KNOT (1U<<31) /* supports more non-continuous rates */
> -
> #define SNDRV_PCM_RATE_8000_44100 (SNDRV_PCM_RATE_8000|SNDRV_PCM_RATE_11025|\
> SNDRV_PCM_RATE_16000|SNDRV_PCM_RATE_22050|\
> SNDRV_PCM_RATE_32000|SNDRV_PCM_RATE_44100)
> diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h
> index 4cd513215bcd..715ceb3eac7c 100644
> --- a/include/uapi/sound/asound.h
> +++ b/include/uapi/sound/asound.h
> @@ -272,6 +272,32 @@ typedef int __bitwise snd_pcm_subformat_t;
> #define SNDRV_PCM_SUBFORMAT_MSBITS_24 ((__force snd_pcm_subformat_t) 3)
> #define SNDRV_PCM_SUBFORMAT_LAST SNDRV_PCM_SUBFORMAT_MSBITS_24
>
> +/* Standard rate bits */
> +#define SNDRV_PCM_RATE_5512 (1U<<0) /* 5512Hz */
> +#define SNDRV_PCM_RATE_8000 (1U<<1) /* 8000Hz */
> +#define SNDRV_PCM_RATE_11025 (1U<<2) /* 11025Hz */
> +#define SNDRV_PCM_RATE_16000 (1U<<3) /* 16000Hz */
> +#define SNDRV_PCM_RATE_22050 (1U<<4) /* 22050Hz */
> +#define SNDRV_PCM_RATE_32000 (1U<<5) /* 32000Hz */
> +#define SNDRV_PCM_RATE_44100 (1U<<6) /* 44100Hz */
> +#define SNDRV_PCM_RATE_48000 (1U<<7) /* 48000Hz */
> +#define SNDRV_PCM_RATE_64000 (1U<<8) /* 64000Hz */
> +#define SNDRV_PCM_RATE_88200 (1U<<9) /* 88200Hz */
> +#define SNDRV_PCM_RATE_96000 (1U<<10) /* 96000Hz */
> +#define SNDRV_PCM_RATE_176400 (1U<<11) /* 176400Hz */
> +#define SNDRV_PCM_RATE_192000 (1U<<12) /* 192000Hz */
> +#define SNDRV_PCM_RATE_352800 (1U<<13) /* 352800Hz */
> +#define SNDRV_PCM_RATE_384000 (1U<<14) /* 384000Hz */
> +#define SNDRV_PCM_RATE_705600 (1U<<15) /* 705600Hz */
> +#define SNDRV_PCM_RATE_768000 (1U<<16) /* 768000Hz */
> +/* extended rates */
> +#define SNDRV_PCM_RATE_12000 (1U<<17) /* 12000Hz */
> +#define SNDRV_PCM_RATE_24000 (1U<<18) /* 24000Hz */
> +#define SNDRV_PCM_RATE_128000 (1U<<19) /* 128000Hz */
> +
> +#define SNDRV_PCM_RATE_CONTINUOUS (1U<<30) /* continuous range */
> +#define SNDRV_PCM_RATE_KNOT (1U<<31) /* supports more non-continuous rates */
> +
> #define SNDRV_PCM_INFO_MMAP 0x00000001 /* hardware supports mmap */
> #define SNDRV_PCM_INFO_MMAP_VALID 0x00000002 /* period data are valid during transfer */
> #define SNDRV_PCM_INFO_DOUBLE 0x00000004 /* Double buffering needed for PCM start/stop */
I will just note that alternatively we could bump topology ABI (wouldn't
be first time) and provide mapping in soc-topology.c for current one.
For ABI+1 we could remove the field from problematic topology struct to
not make SNDRV_PCM_RATE_* part of UAPI and provide some other way to
pass expected rates.
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