ALSA: ymfpci: Define channel maps

Provide channel maps for individual stereo streams of YMFPCI.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/ymfpci/ymfpci_main.c b/sound/pci/ymfpci/ymfpci_main.c
index ee8b636..50b0804 100644
--- a/sound/pci/ymfpci/ymfpci_main.c
+++ b/sound/pci/ymfpci/ymfpci_main.c
@@ -1166,6 +1166,11 @@
 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
 					      snd_dma_pci_data(chip->pci), 64*1024, 256*1024);
 
+	err = snd_pcm_add_chmap_ctls(pcm, SNDRV_PCM_STREAM_PLAYBACK,
+				     snd_pcm_std_chmaps, 2, 0, NULL);
+	if (err < 0)
+		return err;
+
 	if (rpcm)
 		*rpcm = pcm;
 	return 0;
@@ -1257,6 +1262,14 @@
 	.pointer =		snd_ymfpci_playback_pointer,
 };
 
+static const struct snd_pcm_chmap_elem surround_map[] = {
+	{ .channels = 1,
+	  .map = { SNDRV_CHMAP_UNKNOWN } },
+	{ .channels = 2,
+	  .map = { SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
+	{ }
+};
+
 int __devinit snd_ymfpci_pcm_4ch(struct snd_ymfpci *chip, int device, struct snd_pcm ** rpcm)
 {
 	struct snd_pcm *pcm;
@@ -1278,6 +1291,11 @@
 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
 					      snd_dma_pci_data(chip->pci), 64*1024, 256*1024);
 
+	err = snd_pcm_add_chmap_ctls(pcm, SNDRV_PCM_STREAM_PLAYBACK,
+				     surround_map, 2, 0, NULL);
+	if (err < 0)
+		return err;
+
 	if (rpcm)
 		*rpcm = pcm;
 	return 0;