ALSA: hdspm - Introduce hdspm_get_aes_sample_rate()

Helper function to return the AES sample rate class. This class needs to
be translated via HDSPM_bit2freq() to get the more common
representation.

Signed-off-by: Adrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/rme9652/hdspm.c b/sound/pci/rme9652/hdspm.c
index 8e6ce14..b7702b2 100644
--- a/sound/pci/rme9652/hdspm.c
+++ b/sound/pci/rme9652/hdspm.c
@@ -2224,6 +2224,23 @@
 	return 0;
 }
 
+/**
+ * Returns the AES sample rate class for the given card.
+ **/
+static int hdspm_get_aes_sample_rate(struct hdspm *hdspm, int index)
+{
+	int timecode;
+
+	switch (hdspm->io_type) {
+	case AES32:
+		timecode = hdspm_read(hdspm, HDSPM_timecodeRegister);
+		return (timecode >> (4*index)) & 0xF;
+		break;
+	default:
+		break;
+	}
+	return 0;
+}
 
 /**
  * Returns the sample rate class for input source <idx> for