ALSA: dice: old firmware optimization for Dice notification
As long as I tested, Dice-based models produced by TC Electronic with
factory-configured settings transfer no notification within
ensure_phase_lock(). On the other hand, with upgraded firmwares, it
starts to transfer the notification. This seems to be a quirk of earlier
firmwares.
This commit ensures phase lock by reading a register after waiting for
the notification. Even if it's timed-out, ensure_phase_lock() return
success as long as the register has expected clock status.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/firewire/dice/dice-stream.c b/sound/firewire/dice/dice-stream.c
index e4938b0..a64b3cc 100644
--- a/sound/firewire/dice/dice-stream.c
+++ b/sound/firewire/dice/dice-stream.c
@@ -31,7 +31,7 @@
*/
static int ensure_phase_lock(struct snd_dice *dice)
{
- __be32 reg;
+ __be32 reg, nominal;
int err;
err = snd_dice_transaction_read_global(dice, GLOBAL_CLOCK_SELECT,
@@ -48,8 +48,19 @@
return err;
if (wait_for_completion_timeout(&dice->clock_accepted,
- msecs_to_jiffies(NOTIFICATION_TIMEOUT_MS)) == 0)
- return -ETIMEDOUT;
+ msecs_to_jiffies(NOTIFICATION_TIMEOUT_MS)) == 0) {
+ /*
+ * Old versions of Dice firmware transfer no notification when
+ * the same clock status as current one is set. In this case,
+ * just check current clock status.
+ */
+ err = snd_dice_transaction_read_global(dice, GLOBAL_STATUS,
+ &nominal, sizeof(nominal));
+ if (err < 0)
+ return err;
+ if (!(be32_to_cpu(nominal) & STATUS_SOURCE_LOCKED))
+ return -ETIMEDOUT;
+ }
return 0;
}