Merge branch 'for-next' into for-linus

[thirdparty/linux.git] / sound / firewire / tascam / tascam-stream.c

diff --git a/sound/firewire/tascam/tascam-stream.c b/sound/firewire/tascam/tascam-stream.c
index 9e2dc2fe3271da060beabaa0ae71770783f52e63..adf69a520b800bb68eed64adc00e3d68664412e8 100644 (file)
--- a/sound/firewire/tascam/tascam-stream.c
+++ b/sound/firewire/tascam/tascam-stream.c
@@ -8,20 +8,37 @@
 #include <linux/delay.h>
 #include "tascam.h"
 
+#define CLOCK_STATUS_MASK      0xffff0000
+#define CLOCK_CONFIG_MASK      0x0000ffff
+
 #define CALLBACK_TIMEOUT 500
 
 static int get_clock(struct snd_tscm *tscm, u32 *data)
 {
+       int trial = 0;
        __be32 reg;
        int err;
 
-       err = snd_fw_transaction(tscm->unit, TCODE_READ_QUADLET_REQUEST,
-                                TSCM_ADDR_BASE + TSCM_OFFSET_CLOCK_STATUS,
-                                &reg, sizeof(reg), 0);
-       if (err >= 0)
+       while (trial++ < 5) {
+               err = snd_fw_transaction(tscm->unit, TCODE_READ_QUADLET_REQUEST,
+                               TSCM_ADDR_BASE + TSCM_OFFSET_CLOCK_STATUS,
+                               &reg, sizeof(reg), 0);
+               if (err < 0)
+                       return err;
+
                *data = be32_to_cpu(reg);
+               if (*data & CLOCK_STATUS_MASK)
+                       break;
 
-       return err;
+               // In intermediate state after changing clock status.
+               msleep(50);
+       }
+
+       // Still in the intermediate state.
+       if (trial >= 5)
+               return -EAGAIN;
+
+       return 0;
 }
 
 static int set_clock(struct snd_tscm *tscm, unsigned int rate,
@@ -34,7 +51,7 @@ static int set_clock(struct snd_tscm *tscm, unsigned int rate,
        err = get_clock(tscm, &data);
        if (err < 0)
                return err;
-       data &= 0x0000ffff;
+       data &= CLOCK_CONFIG_MASK;
 
        if (rate > 0) {
                data &= 0x000000ff;
@@ -79,17 +96,14 @@ static int set_clock(struct snd_tscm *tscm, unsigned int rate,
 
 int snd_tscm_stream_get_rate(struct snd_tscm *tscm, unsigned int *rate)
 {
-       u32 data = 0x0;
-       unsigned int trials = 0;
+       u32 data;
        int err;
 
-       while (data == 0x0 || trials++ < 5) {
-               err = get_clock(tscm, &data);
-               if (err < 0)
-                       return err;
+       err = get_clock(tscm, &data);
+       if (err < 0)
+               return err;
 
-               data = (data & 0xff000000) >> 24;
-       }
+       data = (data & 0xff000000) >> 24;
 
        /* Check base rate. */
        if ((data & 0x0f) == 0x01)