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@xxxxxxx>
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@xxxxxxx>
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.
Reviewed-by: Jaroslav Kysela <perex@xxxxxxxx>
--
Jaroslav Kysela <perex@xxxxxxxx>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.
