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>
This commit is contained in:
Takashi Sakamoto 2016-02-11 20:18:38 +09:00 committed by Takashi Iwai
parent aec045b80d
commit fbeac84dbe

View file

@ -31,7 +31,7 @@ const unsigned int snd_dice_rates[SND_DICE_RATES_COUNT] = {
*/
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 @@ static int ensure_phase_lock(struct snd_dice *dice)
return err;
if (wait_for_completion_timeout(&dice->clock_accepted,
msecs_to_jiffies(NOTIFICATION_TIMEOUT_MS)) == 0)
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;
}