ALSA: PCM: channel mapping API implementation
This patch implements the basic data types for the standard channel
mapping API handling.
- The definitions of the channel positions and the new TLV types are
added in sound/asound.h and sound/tlv.h, so that they can be
referred from user-space.
- Introduced a new helper function snd_pcm_add_chmap_ctls() to create
control elements representing the channel maps for each PCM
(sub)stream.
- Some standard pre-defined channel maps are provided for
convenience.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/asound.h b/include/sound/asound.h
index 0876a1e..376e756 100644
--- a/include/sound/asound.h
+++ b/include/sound/asound.h
@@ -472,6 +472,36 @@
SNDRV_PCM_TSTAMP_TYPE_LAST = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC,
};
+/* channel positions */
+enum {
+ SNDRV_CHMAP_UNKNOWN = 0,
+ SNDRV_CHMAP_FL, /* front left */
+ SNDRV_CHMAP_FC, /* front center */
+ SNDRV_CHMAP_FR, /* front right */
+ SNDRV_CHMAP_FLC, /* front left center */
+ SNDRV_CHMAP_FRC, /* front right center */
+ SNDRV_CHMAP_RL, /* rear left */
+ SNDRV_CHMAP_RC, /* rear center */
+ SNDRV_CHMAP_RR, /* rear right */
+ SNDRV_CHMAP_RLC, /* rear left center */
+ SNDRV_CHMAP_RRC, /* rear right center */
+ SNDRV_CHMAP_SL, /* side left */
+ SNDRV_CHMAP_SR, /* side right */
+ SNDRV_CHMAP_LFE, /* LFE */
+ SNDRV_CHMAP_FLW, /* front left wide */
+ SNDRV_CHMAP_FRW, /* front right wide */
+ SNDRV_CHMAP_FLH, /* front left high */
+ SNDRV_CHMAP_FCH, /* front center high */
+ SNDRV_CHMAP_FRH, /* front right high */
+ SNDRV_CHMAP_TC, /* top center */
+ SNDRV_CHMAP_NA, /* N/A, silent */
+ SNDRV_CHMAP_LAST = SNDRV_CHMAP_NA,
+};
+
+#define SNDRV_CHMAP_POSITION_MASK 0xffff
+#define SNDRV_CHMAP_PHASE_INVERSE (0x01 << 16)
+#define SNDRV_CHMAP_DRIVER_SPEC (0x02 << 16)
+
#define SNDRV_PCM_IOCTL_PVERSION _IOR('A', 0x00, int)
#define SNDRV_PCM_IOCTL_INFO _IOR('A', 0x01, struct snd_pcm_info)
#define SNDRV_PCM_IOCTL_TSTAMP _IOW('A', 0x02, int)