(line6pcm->pcm->streams[stream].substream)
/*
- PCM mode bits and masks.
- "ALSA": operations triggered by applications via ALSA
- "MONITOR": software monitoring
- "IMPULSE": optional impulse response operation
+ PCM mode bits.
+
+ There are several features of the Line6 USB driver which require PCM
+ data to be exchanged with the device:
+ *) PCM playback and capture via ALSA
+ *) software monitoring (for devices without hardware monitoring)
+ *) optional impulse response measurement
+ However, from the device's point of view, there is just a single
+ capture and playback stream, which must be shared between these
+ subsystems. It is therefore necessary to maintain the state of the
+ subsystems with respect to PCM usage. We define several constants of
+ the form LINE6_BIT_PCM_<subsystem>_<direction>_<resource> with the
+ following meanings:
+ *) <subsystem> is one of
+ -) ALSA: PCM playback and capture via ALSA
+ -) MONITOR: software monitoring
+ -) IMPULSE: optional impulse response measurement
+ *) <direction> is one of
+ -) PLAYBACK: audio output (from host to device)
+ -) CAPTURE: audio input (from device to host)
+ *) <resource> is one of
+ -) BUFFER: buffer required by PCM data stream
+ -) STREAM: actual PCM data stream
+
+ The subsystems call line6_pcm_acquire() to acquire the (shared)
+ resources needed for a particular operation (e.g., allocate the buffer
+ for ALSA playback or start the capture stream for software monitoring).
+ When a resource is no longer needed, it is released by calling
+ line6_pcm_release(). Buffer allocation and stream startup are handled
+ separately to allow the ALSA kernel driver to perform them at
+ appropriate places (since the callback which starts a PCM stream is not
+ allowed to sleep).
*/
enum {
- /* individual bits: */
- BIT_PCM_ALSA_PLAYBACK,
- BIT_PCM_ALSA_CAPTURE,
- BIT_PCM_MONITOR_PLAYBACK,
- BIT_PCM_MONITOR_CAPTURE,
+ /* individual bit indices: */
+ LINE6_INDEX_PCM_ALSA_PLAYBACK_BUFFER,
+ LINE6_INDEX_PCM_ALSA_PLAYBACK_STREAM,
+ LINE6_INDEX_PCM_ALSA_CAPTURE_BUFFER,
+ LINE6_INDEX_PCM_ALSA_CAPTURE_STREAM,
+ LINE6_INDEX_PCM_MONITOR_PLAYBACK_BUFFER,
+ LINE6_INDEX_PCM_MONITOR_PLAYBACK_STREAM,
+ LINE6_INDEX_PCM_MONITOR_CAPTURE_BUFFER,
+ LINE6_INDEX_PCM_MONITOR_CAPTURE_STREAM,
#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
- BIT_PCM_IMPULSE_PLAYBACK,
- BIT_PCM_IMPULSE_CAPTURE,
+ LINE6_INDEX_PCM_IMPULSE_PLAYBACK_BUFFER,
+ LINE6_INDEX_PCM_IMPULSE_PLAYBACK_STREAM,
+ LINE6_INDEX_PCM_IMPULSE_CAPTURE_BUFFER,
+ LINE6_INDEX_PCM_IMPULSE_CAPTURE_STREAM,
#endif
- BIT_PAUSE_PLAYBACK,
- BIT_PREPARED,
-
- /* individual masks: */
-/* *INDENT-OFF* */
- MASK_PCM_ALSA_PLAYBACK = 1 << BIT_PCM_ALSA_PLAYBACK,
- MASK_PCM_ALSA_CAPTURE = 1 << BIT_PCM_ALSA_CAPTURE,
- MASK_PCM_MONITOR_PLAYBACK = 1 << BIT_PCM_MONITOR_PLAYBACK,
- MASK_PCM_MONITOR_CAPTURE = 1 << BIT_PCM_MONITOR_CAPTURE,
+ LINE6_INDEX_PAUSE_PLAYBACK,
+ LINE6_INDEX_PREPARED,
+
+ /* individual bit masks: */
+ LINE6_BIT(PCM_ALSA_PLAYBACK_BUFFER),
+ LINE6_BIT(PCM_ALSA_PLAYBACK_STREAM),
+ LINE6_BIT(PCM_ALSA_CAPTURE_BUFFER),
+ LINE6_BIT(PCM_ALSA_CAPTURE_STREAM),
+ LINE6_BIT(PCM_MONITOR_PLAYBACK_BUFFER),
+ LINE6_BIT(PCM_MONITOR_PLAYBACK_STREAM),
+ LINE6_BIT(PCM_MONITOR_CAPTURE_BUFFER),
+ LINE6_BIT(PCM_MONITOR_CAPTURE_STREAM),
#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
- MASK_PCM_IMPULSE_PLAYBACK = 1 << BIT_PCM_IMPULSE_PLAYBACK,
- MASK_PCM_IMPULSE_CAPTURE = 1 << BIT_PCM_IMPULSE_CAPTURE,
+ LINE6_BIT(PCM_IMPULSE_PLAYBACK_BUFFER),
+ LINE6_BIT(PCM_IMPULSE_PLAYBACK_STREAM),
+ LINE6_BIT(PCM_IMPULSE_CAPTURE_BUFFER),
+ LINE6_BIT(PCM_IMPULSE_CAPTURE_STREAM),
#endif
- MASK_PAUSE_PLAYBACK = 1 << BIT_PAUSE_PLAYBACK,
- MASK_PREPARED = 1 << BIT_PREPARED,
-/* *INDENT-ON* */
+ LINE6_BIT(PAUSE_PLAYBACK),
+ LINE6_BIT(PREPARED),
- /* combined masks (by operation): */
- MASK_PCM_ALSA = MASK_PCM_ALSA_PLAYBACK | MASK_PCM_ALSA_CAPTURE,
- MASK_PCM_MONITOR = MASK_PCM_MONITOR_PLAYBACK | MASK_PCM_MONITOR_CAPTURE,
+ /* combined bit masks (by operation): */
+ LINE6_BITS_PCM_ALSA_BUFFER =
+ LINE6_BIT_PCM_ALSA_PLAYBACK_BUFFER |
+ LINE6_BIT_PCM_ALSA_CAPTURE_BUFFER,
+
+ LINE6_BITS_PCM_ALSA_STREAM =
+ LINE6_BIT_PCM_ALSA_PLAYBACK_STREAM |
+ LINE6_BIT_PCM_ALSA_CAPTURE_STREAM,
+
+ LINE6_BITS_PCM_MONITOR =
+ LINE6_BIT_PCM_MONITOR_PLAYBACK_BUFFER |
+ LINE6_BIT_PCM_MONITOR_PLAYBACK_STREAM |
+ LINE6_BIT_PCM_MONITOR_CAPTURE_BUFFER |
+ LINE6_BIT_PCM_MONITOR_CAPTURE_STREAM,
+
+#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
+ LINE6_BITS_PCM_IMPULSE =
+ LINE6_BIT_PCM_IMPULSE_PLAYBACK_BUFFER |
+ LINE6_BIT_PCM_IMPULSE_PLAYBACK_STREAM |
+ LINE6_BIT_PCM_IMPULSE_CAPTURE_BUFFER |
+ LINE6_BIT_PCM_IMPULSE_CAPTURE_STREAM,
+#endif
+
+ /* combined bit masks (by direction): */
+ LINE6_BITS_PLAYBACK_BUFFER =
+#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
+ LINE6_BIT_PCM_IMPULSE_PLAYBACK_BUFFER |
+#endif
+ LINE6_BIT_PCM_ALSA_PLAYBACK_BUFFER |
+ LINE6_BIT_PCM_MONITOR_PLAYBACK_BUFFER ,
+
+ LINE6_BITS_PLAYBACK_STREAM =
+#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
+ LINE6_BIT_PCM_IMPULSE_PLAYBACK_STREAM |
+#endif
+ LINE6_BIT_PCM_ALSA_PLAYBACK_STREAM |
+ LINE6_BIT_PCM_MONITOR_PLAYBACK_STREAM ,
+
+ LINE6_BITS_CAPTURE_BUFFER =
#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
- MASK_PCM_IMPULSE = MASK_PCM_IMPULSE_PLAYBACK | MASK_PCM_IMPULSE_CAPTURE,
+ LINE6_BIT_PCM_IMPULSE_CAPTURE_BUFFER |
#endif
+ LINE6_BIT_PCM_ALSA_CAPTURE_BUFFER |
+ LINE6_BIT_PCM_MONITOR_CAPTURE_BUFFER ,
- /* combined masks (by direction): */
+ LINE6_BITS_CAPTURE_STREAM =
#ifdef CONFIG_LINE6_USB_IMPULSE_RESPONSE
- MASK_PLAYBACK =
- MASK_PCM_ALSA_PLAYBACK | MASK_PCM_MONITOR_PLAYBACK |
- MASK_PCM_IMPULSE_PLAYBACK,
- MASK_CAPTURE =
- MASK_PCM_ALSA_CAPTURE | MASK_PCM_MONITOR_CAPTURE |
- MASK_PCM_IMPULSE_CAPTURE
-#else
- MASK_PLAYBACK = MASK_PCM_ALSA_PLAYBACK | MASK_PCM_MONITOR_PLAYBACK,
- MASK_CAPTURE = MASK_PCM_ALSA_CAPTURE | MASK_PCM_MONITOR_CAPTURE
+ LINE6_BIT_PCM_IMPULSE_CAPTURE_STREAM |
#endif
+ LINE6_BIT_PCM_ALSA_CAPTURE_STREAM |
+ LINE6_BIT_PCM_MONITOR_CAPTURE_STREAM,
+
+ LINE6_BITS_STREAM =
+ LINE6_BITS_PLAYBACK_STREAM |
+ LINE6_BITS_CAPTURE_STREAM
};
struct line6_pcm_properties {
#endif
/**
- Several status bits (see BIT_*).
+ Several status bits (see LINE6_BIT_*).
*/
unsigned long flags;
extern int snd_line6_trigger(struct snd_pcm_substream *substream, int cmd);
extern int snd_line6_prepare(struct snd_pcm_substream *substream);
extern void line6_pcm_disconnect(struct snd_line6_pcm *line6pcm);
-extern int line6_pcm_start(struct snd_line6_pcm *line6pcm, int channels);
-extern int line6_pcm_stop(struct snd_line6_pcm *line6pcm, int channels);
+extern int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int channels);
+extern int line6_pcm_release(struct snd_line6_pcm *line6pcm, int channels);
#endif
projects / linux-2.6-block.git / blobdiff