ALSA: ctxfi - Use native timer interrupt on emu20k1

emu20k1 has a native timer interrupt based on the audio clock, which
is more accurate than the system timer (from the synchronization POV).
This patch adds the code to handle this with multiple streams.

The system timer is still used on emu20k2, and can be used also for
emu20k1 easily by changing USE_SYSTEM_TIMER to 1 in cttimer.c.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 29 insertions, 0 deletions

diff --git a/sound/pci/ctxfi/cttimer.h b/sound/pci/ctxfi/cttimer.h
new file mode 100644
index 00000000000..97934822929
--- /dev/null
+++ b/sound/pci/ctxfi/cttimer.h
@@ -0,0 +1,29 @@
+/*
+ * Timer handling
+ */
+
+#ifndef __CTTIMER_H
+#define __CTTIMER_H
+
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/list.h>
+
+struct snd_pcm_substream;
+struct ct_atc;
+struct ct_atc_pcm;
+
+struct ct_timer;
+struct ct_timer_instance;
+
+struct ct_timer *ct_timer_new(struct ct_atc *atc);
+void ct_timer_free(struct ct_timer *atimer);
+
+struct ct_timer_instance *
+ct_timer_instance_new(struct ct_timer *atimer, struct ct_atc_pcm *apcm);
+void ct_timer_instance_free(struct ct_timer_instance *ti);
+void ct_timer_start(struct ct_timer_instance *ti);
+void ct_timer_stop(struct ct_timer_instance *ti);
+void ct_timer_prepare(struct ct_timer_instance *ti);
+
+#endif /* __CTTIMER_H */