ALSA: firewire-motu: minor code refactoring for protocol version 2

This commit adds some helper functions to parse register value for
source of sampling clock and nominal sampling transmission frequency.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20191030080644.1704-5-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/firewire/motu/motu-protocol-v2.c b/sound/firewire/motu/motu-protocol-v2.c
index 2757e5b42b9b19c5eba8b5506d015d8f4c436824..cb0e58a9f33d8ff4791b47d41b69f0848296e29e 100644 (file)
--- a/sound/firewire/motu/motu-protocol-v2.c
+++ b/sound/firewire/motu/motu-protocol-v2.c
@@ -26,10 +26,20 @@
 #define  V2_OPT_IFACE_MODE_ADAT                        1
 #define  V2_OPT_IFACE_MODE_SPDIF               2
 
+static int get_clock_rate(u32 data, unsigned int *rate)
+{
+       unsigned int index = (data & V2_CLOCK_RATE_MASK) >> V2_CLOCK_RATE_SHIFT;
+       if (index >= ARRAY_SIZE(snd_motu_clock_rates))
+               return -EIO;
+
+       *rate = snd_motu_clock_rates[index];
+
+       return 0;
+}
+
 static int v2_get_clock_rate(struct snd_motu *motu, unsigned int *rate)
 {
        __be32 reg;
-       unsigned int index;
        int err;
 
        err = snd_motu_transaction_read(motu, V2_CLOCK_STATUS_OFFSET, &reg,
@@ -37,13 +47,7 @@ static int v2_get_clock_rate(struct snd_motu *motu, unsigned int *rate)
        if (err < 0)
                return err;
 
-       index = (be32_to_cpu(reg) & V2_CLOCK_RATE_MASK) >> V2_CLOCK_RATE_SHIFT;
-       if (index >= ARRAY_SIZE(snd_motu_clock_rates))
-               return -EIO;
-
-       *rate = snd_motu_clock_rates[index];
-
-       return 0;
+       return get_clock_rate(be32_to_cpu(reg), rate);
 }
 
 static int v2_set_clock_rate(struct snd_motu *motu, unsigned int rate)
@@ -79,38 +83,33 @@ static int v2_set_clock_rate(struct snd_motu *motu, unsigned int rate)
                                          sizeof(reg));
 }
 
-static int v2_get_clock_source(struct snd_motu *motu,
-                              enum snd_motu_clock_source *src)
+static int get_clock_source(struct snd_motu *motu, u32 data,
+                           enum snd_motu_clock_source *src)
 {
-       __be32 reg;
-       unsigned int index;
-       int err;
-
-       err = snd_motu_transaction_read(motu, V2_CLOCK_STATUS_OFFSET, &reg,
-                                       sizeof(reg));
-       if (err < 0)
-               return err;
-
-       index = be32_to_cpu(reg) & V2_CLOCK_SRC_MASK;
+       unsigned int index = data & V2_CLOCK_SRC_MASK;
        if (index > 5)
                return -EIO;
 
-       /* To check the configuration of optical interface. */
-       err = snd_motu_transaction_read(motu, V2_IN_OUT_CONF_OFFSET, &reg,
-                                       sizeof(reg));
-       if (err < 0)
-               return err;
-
        switch (index) {
        case 0:
                *src = SND_MOTU_CLOCK_SOURCE_INTERNAL;
                break;
        case 1:
+       {
+               __be32 reg;
+
+               // To check the configuration of optical interface.
+               int err = snd_motu_transaction_read(motu, V2_IN_OUT_CONF_OFFSET,
+                                                   &reg, sizeof(reg));
+               if (err < 0)
+                       return err;
+
                if (be32_to_cpu(reg) & 0x00000200)
                        *src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT;
                else
                        *src = SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT;
                break;
+       }
        case 2:
                *src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_COAX;
                break;
@@ -130,6 +129,20 @@ static int v2_get_clock_source(struct snd_motu *motu,
        return 0;
 }
 
+static int v2_get_clock_source(struct snd_motu *motu,
+                              enum snd_motu_clock_source *src)
+{
+       __be32 reg;
+       int err;
+
+       err = snd_motu_transaction_read(motu, V2_CLOCK_STATUS_OFFSET, &reg,
+                                       sizeof(reg));
+       if (err < 0)
+               return err;
+
+       return get_clock_source(motu, be32_to_cpu(reg), src);
+}
+
 static int v2_switch_fetching_mode(struct snd_motu *motu, bool enable)
 {
        __be32 reg;