ALSA: ctxfi: Implement channel maps

Assign the multi-channel map to front PCM, and other channel map to
each other channel PCM.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/ctxfi/ctpcm.c

@@ -395,12 +395,38 @@ static struct snd_pcm_ops ct_pcm_capture_ops = {
 	.page		= snd_pcm_sgbuf_ops_page,
 };
 
+static const struct snd_pcm_chmap_elem surround_map[] = {
+	{ .channels = 1,
+	  .map = { SNDRV_CHMAP_RC } },
+	{ .channels = 2,
+	  .map = { SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
+	{ }
+};
+
+static const struct snd_pcm_chmap_elem clfe_map[] = {
+	{ .channels = 1,
+	  .map = { SNDRV_CHMAP_FC } },
+	{ .channels = 2,
+	  .map = { SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
+	{ }
+};
+
+static const struct snd_pcm_chmap_elem side_map[] = {
+	{ .channels = 1,
+	  .map = { SNDRV_CHMAP_RC } },
+	{ .channels = 2,
+	  .map = { SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
+	{ }
+};
+
 /* Create ALSA pcm device */
 int ct_alsa_pcm_create(struct ct_atc *atc,
 		       enum CTALSADEVS device,
 		       const char *device_name)
 {
 	struct snd_pcm *pcm;
+	const struct snd_pcm_chmap_elem *map;
+	int chs;
 	int err;
 	int playback_count, capture_count;
 
@@ -427,6 +453,30 @@ int ct_alsa_pcm_create(struct ct_atc *atc,
 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV_SG,
 			snd_dma_pci_data(atc->pci), 128*1024, 128*1024);
 
+	chs = 2;
+	switch (device) {
+	case FRONT:
+		chs = 8;
+		map = snd_pcm_std_chmaps;
+		break;
+	case SURROUND:
+		map = surround_map;
+		break;
+	case CLFE:
+		map = clfe_map;
+		break;
+	case SIDE:
+		map = side_map;
+		break;
+	default:
+		map = snd_pcm_std_chmaps;
+		break;
+	}
+	err = snd_pcm_add_chmap_ctls(pcm, SNDRV_PCM_STREAM_PLAYBACK, map, chs,
+				     0, NULL);
+	if (err < 0)
+		return err;
+
 #ifdef CONFIG_PM_SLEEP
 	atc->pcms[device] = pcm;
 #endif