UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

ALSA: firewire-motu: wait for notification when changing clock configuration for protocol v3 

It costs expensive to change clock configuration for models of protocol
version 3. In current implementation, speculative strategy is used to
finish the operation; just waiting for 4 seconds. As long as I investigate,
when accepting and changing clock status actually, the device sends
notification with mask.

This commit uses wise way to wait for the notification after changing
sampling clock rate during 4 seconds.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20200614141221.53527-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Sakamoto 2020-06-14 23:12:21 +09:00 committed by Takashi Iwai
parent d9d52398b7
commit 675398674c
1 changed files with 13 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
sound/firewire/motu/motu-protocol-v3.c
View File

@ -24,6 +24,9 @@
#define V3_NO_ADAT_OPT_OUT_IFACE_A 0x00040000
#define V3_NO_ADAT_OPT_OUT_IFACE_B 0x00400000
#define V3_MSG_FLAG_CLK_CHANGED 0x00000002
#define V3_CLK_WAIT_MSEC 4000
int snd_motu_protocol_v3_get_clock_rate(struct snd_motu *motu,
unsigned int *rate)
{
@ -79,9 +82,16 @@ int snd_motu_protocol_v3_set_clock_rate(struct snd_motu *motu,
return err;
if (need_to_wait) {
/* Cost expensive. */
if (msleep_interruptible(4000) > 0)
return -EINTR;
int result;
motu->msg = 0;
result = wait_event_interruptible_timeout(motu->hwdep_wait,
motu->msg & V3_MSG_FLAG_CLK_CHANGED,
msecs_to_jiffies(V3_CLK_WAIT_MSEC));
if (result < 0)
return result;
if (result == 0)
return -ETIMEDOUT;
}
return 0;