ALSA: emu10k1 - delay the PCM interrupts (add pcm_irq_delay parameter)
With some hardware combinations, the PCM interrupts are acknowledged
before the period boundary from the emu10k1 chip. The midlevel PCM code
gets confused and the playback stream is interrupted.
It seems that the interrupt processing shift by 2 samples is enough
to fix this issue. This default value does not harm other,
non-affected hardware.
More information: Kernel bugzilla bug#16300
[A copmile warning fixed by tiwai]
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/emu10k1/emupcm.c b/sound/pci/emu10k1/emupcm.c
index 55b83ef..622bace 100644
--- a/sound/pci/emu10k1/emupcm.c
+++ b/sound/pci/emu10k1/emupcm.c
@@ -332,7 +332,7 @@
evoice->epcm->ccca_start_addr = start_addr + ccis;
if (extra) {
start_addr += ccis;
- end_addr += ccis;
+ end_addr += ccis + emu->delay_pcm_irq;
}
if (stereo && !extra) {
snd_emu10k1_ptr_write(emu, CPF, voice, CPF_STEREO_MASK);
@@ -360,7 +360,9 @@
/* Assumption that PT is already 0 so no harm overwriting */
snd_emu10k1_ptr_write(emu, PTRX, voice, (send_amount[0] << 8) | send_amount[1]);
snd_emu10k1_ptr_write(emu, DSL, voice, end_addr | (send_amount[3] << 24));
- snd_emu10k1_ptr_write(emu, PSST, voice, start_addr | (send_amount[2] << 24));
+ snd_emu10k1_ptr_write(emu, PSST, voice,
+ (start_addr + (extra ? emu->delay_pcm_irq : 0)) |
+ (send_amount[2] << 24));
if (emu->card_capabilities->emu_model)
pitch_target = PITCH_48000; /* Disable interpolators on emu1010 card */
else
@@ -732,6 +734,23 @@
snd_emu10k1_ptr_write(emu, IP, voice, 0);
}
+static inline void snd_emu10k1_playback_mangle_extra(struct snd_emu10k1 *emu,
+ struct snd_emu10k1_pcm *epcm,
+ struct snd_pcm_substream *substream,
+ struct snd_pcm_runtime *runtime)
+{
+ unsigned int ptr, period_pos;
+
+ /* try to sychronize the current position for the interrupt
+ source voice */
+ period_pos = runtime->status->hw_ptr - runtime->hw_ptr_interrupt;
+ period_pos %= runtime->period_size;
+ ptr = snd_emu10k1_ptr_read(emu, CCCA, epcm->extra->number);
+ ptr &= ~0x00ffffff;
+ ptr |= epcm->ccca_start_addr + period_pos;
+ snd_emu10k1_ptr_write(emu, CCCA, epcm->extra->number, ptr);
+}
+
static int snd_emu10k1_playback_trigger(struct snd_pcm_substream *substream,
int cmd)
{
@@ -753,6 +772,8 @@
/* follow thru */
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
case SNDRV_PCM_TRIGGER_RESUME:
+ if (cmd == SNDRV_PCM_TRIGGER_PAUSE_RELEASE)
+ snd_emu10k1_playback_mangle_extra(emu, epcm, substream, runtime);
mix = &emu->pcm_mixer[substream->number];
snd_emu10k1_playback_prepare_voice(emu, epcm->voices[0], 1, 0, mix);
snd_emu10k1_playback_prepare_voice(emu, epcm->voices[1], 0, 0, mix);
@@ -869,8 +890,9 @@
#endif
/*
printk(KERN_DEBUG
- "ptr = 0x%x, buffer_size = 0x%x, period_size = 0x%x\n",
- ptr, runtime->buffer_size, runtime->period_size);
+ "ptr = 0x%lx, buffer_size = 0x%lx, period_size = 0x%lx\n",
+ (long)ptr, (long)runtime->buffer_size,
+ (long)runtime->period_size);
*/
return ptr;
}