ALSA: firewire-motu: refactoring protocol v2 for fetching mode switch

This commit splits the method to switch fetching mode for protocol
version 2 so that model-dependent operations are explicitly defined.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20200519111641.123211-15-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 2e6c3cc..e59e69a 100644 (file)
--- a/sound/firewire/motu/motu-protocol-v2.c
+++ b/sound/firewire/motu/motu-protocol-v2.c
@@ -170,52 +170,69 @@ int snd_motu_protocol_v2_get_clock_source(struct snd_motu *motu,
        return get_clock_source(motu, be32_to_cpu(reg), src);
 }
 
-int snd_motu_protocol_v2_switch_fetching_mode(struct snd_motu *motu,
-                                             bool enable)
+// Expected for Traveler and 896HD, which implements Altera Cyclone EP1C3.
+static int switch_fetching_mode_cyclone(struct snd_motu *motu, u32 *data,
+                                       bool enable)
 {
-       enum snd_motu_clock_source src;
-       __be32 reg;
-       u32 data;
-       int err = 0;
+       *data |= V2_CLOCK_MODEL_SPECIFIC;
 
-       // 828mkII implements Altera ACEX 1K EP1K30. Nothing to do.
-       if (motu->spec == &snd_motu_spec_828mk2)
-               return 0;
+       return 0;
+}
 
-       err = snd_motu_transaction_read(motu, V2_CLOCK_STATUS_OFFSET, &reg,
-                                       sizeof(reg));
+// For UltraLite and 8pre, which implements Xilinx Spartan XC3S200.
+static int switch_fetching_mode_spartan(struct snd_motu *motu, u32 *data,
+                                       bool enable)
+{
+       unsigned int rate;
+       enum snd_motu_clock_source src;
+       int err;
+
+       err = get_clock_source(motu, *data, &src);
        if (err < 0)
                return err;
-       data = be32_to_cpu(reg);
 
-       err = get_clock_source(motu, data, &src);
+       err = get_clock_rate(*data, &rate);
        if (err < 0)
                return err;
 
-       data &= ~(V2_CLOCK_FETCH_ENABLE | V2_CLOCK_MODEL_SPECIFIC);
-       if (enable)
-               data |= V2_CLOCK_FETCH_ENABLE;
+       if (src == SND_MOTU_CLOCK_SOURCE_SPH && rate > 48000)
+               *data |= V2_CLOCK_MODEL_SPECIFIC;
 
-       if (motu->spec == &snd_motu_spec_traveler) {
-               // Expected for Traveler and 896HD, which implements Altera
-               // Cyclone EP1C3.
-               data |= V2_CLOCK_MODEL_SPECIFIC;
+       return 0;
+}
+
+int snd_motu_protocol_v2_switch_fetching_mode(struct snd_motu *motu,
+                                             bool enable)
+{
+       if (motu->spec == &snd_motu_spec_828mk2) {
+               // 828mkII implements Altera ACEX 1K EP1K30. Nothing to do.
+               return 0;
        } else {
-               // For UltraLite and 8pre, which implements Xilinx Spartan
-               // XC3S200.
-               unsigned int rate;
+               __be32 reg;
+               u32 data;
+               int err;
 
-               err = get_clock_rate(data, &rate);
+               err = snd_motu_transaction_read(motu, V2_CLOCK_STATUS_OFFSET,
+                                               &reg, sizeof(reg));
                if (err < 0)
                        return err;
+               data = be32_to_cpu(reg);
 
-               if (src == SND_MOTU_CLOCK_SOURCE_SPH && rate > 48000)
-                       data |= V2_CLOCK_MODEL_SPECIFIC;
-       }
+               data &= ~(V2_CLOCK_FETCH_ENABLE | V2_CLOCK_MODEL_SPECIFIC);
+               if (enable)
+                       data |= V2_CLOCK_FETCH_ENABLE;
 
-       reg = cpu_to_be32(data);
-       return snd_motu_transaction_write(motu, V2_CLOCK_STATUS_OFFSET, &reg,
-                                         sizeof(reg));
+               if (motu->spec == &snd_motu_spec_traveler)
+                       err = switch_fetching_mode_cyclone(motu, &data, enable);
+               else
+                       err = switch_fetching_mode_spartan(motu, &data, enable);
+               if (err < 0)
+                       return err;
+
+               reg = cpu_to_be32(data);
+               return snd_motu_transaction_write(motu, V2_CLOCK_STATUS_OFFSET,
+                                                 &reg, sizeof(reg));
+       }
 }
 
 static int detect_packet_formats_828mk2(struct snd_motu *motu, u32 data)