ALSA: timer: Unify master/slave linking code

The code in both snd_timer_check_master() and snd_timer_check_slave()
are almost identical, both check whether the master/slave link and
does linkage.  Factor out the common code and call it from both
functions for readability.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20191107192008.32331-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2019-11-07 20:20:06 +01:00
parent 66a8966aac
commit ebfc6de29a
1 changed files with 33 additions and 33 deletions

View File

@ -163,6 +163,28 @@ static void snd_timer_request(struct snd_timer_id *tid)
#endif
/* move the slave if it belongs to the master; return 1 if match */
static int check_matching_master_slave(struct snd_timer_instance *master,
struct snd_timer_instance *slave)
{
if (slave->slave_class != master->slave_class ||
slave->slave_id != master->slave_id)
return 0;
if (master->timer->num_instances >= master->timer->max_instances)
return -EBUSY;
list_move_tail(&slave->open_list, &master->slave_list_head);
master->timer->num_instances++;
spin_lock_irq(&slave_active_lock);
spin_lock(&master->timer->lock);
slave->master = master;
slave->timer = master->timer;
if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
list_add_tail(&slave->active_list, &master->slave_active_head);
spin_unlock(&master->timer->lock);
spin_unlock_irq(&slave_active_lock);
return 1;
}
/*
* look for a master instance matching with the slave id of the given slave.
* when found, relink the open_link of the slave.
@ -173,27 +195,18 @@ static int snd_timer_check_slave(struct snd_timer_instance *slave)
{
struct snd_timer *timer;
struct snd_timer_instance *master;
int err = 0;
/* FIXME: it's really dumb to look up all entries.. */
list_for_each_entry(timer, &snd_timer_list, device_list) {
list_for_each_entry(master, &timer->open_list_head, open_list) {
if (slave->slave_class == master->slave_class &&
slave->slave_id == master->slave_id) {
if (master->timer->num_instances >=
master->timer->max_instances)
return -EBUSY;
list_move_tail(&slave->open_list,
&master->slave_list_head);
master->timer->num_instances++;
spin_lock_irq(&slave_active_lock);
slave->master = master;
slave->timer = master->timer;
spin_unlock_irq(&slave_active_lock);
return 0;
err = check_matching_master_slave(master, slave);
if (err != 0) /* match found or error */
goto out;
}
}
}
return 0;
out:
return err < 0 ? err : 0;
}
/*
@ -205,28 +218,15 @@ static int snd_timer_check_slave(struct snd_timer_instance *slave)
static int snd_timer_check_master(struct snd_timer_instance *master)
{
struct snd_timer_instance *slave, *tmp;
int err = 0;
/* check all pending slaves */
list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
if (slave->slave_class == master->slave_class &&
slave->slave_id == master->slave_id) {
if (master->timer->num_instances >=
master->timer->max_instances)
return -EBUSY;
list_move_tail(&slave->open_list, &master->slave_list_head);
master->timer->num_instances++;
spin_lock_irq(&slave_active_lock);
spin_lock(&master->timer->lock);
slave->master = master;
slave->timer = master->timer;
if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
list_add_tail(&slave->active_list,
&master->slave_active_head);
spin_unlock(&master->timer->lock);
spin_unlock_irq(&slave_active_lock);
err = check_matching_master_slave(master, slave);
if (err < 0)
break;
}
}
return 0;
return err < 0 ? err : 0;
}
static int snd_timer_close_locked(struct snd_timer_instance *timeri,