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| author | Oswald Buddenhagen <oswald.buddenhagen@gmx.de> | 2023-05-18 17:03:38 +0300 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2023-05-18 17:41:19 +0300 |
| commit | 08e55ae996cbdbd76c3eb12fcad6cc79cba7ddbc (patch) | |
| tree | c73f7ff93eec45ea080d289cc7cc1bac427bcd7f /sound/pci/emu10k1/emupcm.c | |
| parent | 5c2664cc09f94ba11c61908d5c7dac1c35d6dee8 (diff) | |
| download | linux-08e55ae996cbdbd76c3eb12fcad6cc79cba7ddbc.tar.xz | |
ALSA: emu10k1: enable bit-exact playback, part 3: pitch
CPF_CURRENTPITCH starts swerving towards PTRX_PITCHTARGET as soon as
that is set. In practice this means that CPF_FRACADDRESS may acquire a
non-zero value before we manage to force CPF_CURRENTPITCH to the final
value, which would prevent bit-for-bit reproduction.
To avoid that this state persists, we now reset CPF_FRACADDRESS when
setting CPF_CURRENTPITCH, and to (mostly) avoid that it progresses too
far in the first place (possibly even reaching CCCA_CURRADDR), we write
PTRX and CPF in one critical section (though NMIs, etc. still make this
unreliable).
Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Link: https://lore.kernel.org/r/20230518140339.3722279-2-oswald.buddenhagen@gmx.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/pci/emu10k1/emupcm.c')
| -rw-r--r-- | sound/pci/emu10k1/emupcm.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/sound/pci/emu10k1/emupcm.c b/sound/pci/emu10k1/emupcm.c index 1ca16f0ddbed..0b23ff8d9c3b 100644 --- a/sound/pci/emu10k1/emupcm.c +++ b/sound/pci/emu10k1/emupcm.c @@ -601,6 +601,17 @@ static void snd_emu10k1_playback_mute_voice(struct snd_emu10k1 *emu, snd_emu10k1_playback_commit_volume(emu, evoice, 0); } +static void snd_emu10k1_playback_commit_pitch(struct snd_emu10k1 *emu, + u32 voice, u32 pitch_target) +{ + u32 ptrx = snd_emu10k1_ptr_read(emu, PTRX, voice); + u32 cpf = snd_emu10k1_ptr_read(emu, CPF, voice); + snd_emu10k1_ptr_write_multiple(emu, voice, + PTRX, (ptrx & ~PTRX_PITCHTARGET_MASK) | pitch_target, + CPF, (cpf & ~(CPF_CURRENTPITCH_MASK | CPF_FRACADDRESS_MASK)) | pitch_target, + REGLIST_END); +} + static void snd_emu10k1_playback_trigger_voice(struct snd_emu10k1 *emu, struct snd_emu10k1_voice *evoice) { @@ -616,8 +627,7 @@ static void snd_emu10k1_playback_trigger_voice(struct snd_emu10k1 *emu, pitch_target = PITCH_48000; /* Disable interpolators on emu1010 card */ else pitch_target = emu10k1_calc_pitch_target(runtime->rate); - snd_emu10k1_ptr_write(emu, PTRX_PITCHTARGET, voice, pitch_target); - snd_emu10k1_ptr_write(emu, CPF_CURRENTPITCH, voice, pitch_target); + snd_emu10k1_playback_commit_pitch(emu, voice, pitch_target << 16); } static void snd_emu10k1_playback_stop_voice(struct snd_emu10k1 *emu, @@ -626,8 +636,7 @@ static void snd_emu10k1_playback_stop_voice(struct snd_emu10k1 *emu, unsigned int voice; voice = evoice->number; - snd_emu10k1_ptr_write(emu, PTRX_PITCHTARGET, voice, 0); - snd_emu10k1_ptr_write(emu, CPF_CURRENTPITCH, voice, 0); + snd_emu10k1_playback_commit_pitch(emu, voice, 0); } static void snd_emu10k1_playback_set_running(struct snd_emu10k1 *emu, |