[ALSA] timers: add module refcounting for global timers

Modules: RTC timer driver,Timer Midlevel

Add a module pointer to the timer structure and use it for refcounting
instead of the card's module pointer to prevent the global timer
modules (rtctimer and hpetimer) from being removed while in use.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

2 files changed, 7 insertions, 4 deletions

diff --git a/sound/core/rtctimer.c b/sound/core/rtctimer.c
index 8762ff8938c2..c3c18568207e 100644
--- a/sound/core/rtctimer.c
+++ b/sound/core/rtctimer.c
@@ -124,7 +124,8 @@ static int __init rtctimer_init(void)
 
         if (rtctimer_freq < 2 || rtctimer_freq > 8192 ||
             (rtctimer_freq & (rtctimer_freq - 1)) != 0) {
-                snd_printk(KERN_ERR "rtctimer: invalid frequency %d\n", rtctimer_freq);
+                snd_printk(KERN_ERR "rtctimer: invalid frequency %d\n",
+                           rtctimer_freq);
                 return -EINVAL;
         }
 
@@ -133,6 +134,7 @@ static int __init rtctimer_init(void)
         if (err < 0)
                 return err;
 
+        timer->module = THIS_MODULE;
         strcpy(timer->name, "RTC timer");
         timer->hw = rtc_hw;
         timer->hw.resolution = NANO_SEC / rtctimer_freq;
diff --git a/sound/core/timer.c b/sound/core/timer.c
index b02681eaea75..c8496c7b8df8 100644
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -113,7 +113,7 @@ static snd_timer_instance_t *snd_timer_instance_new(char *owner, snd_timer_t *ti
         INIT_LIST_HEAD(&timeri->slave_active_head);
 
         timeri->timer = timer;
-        if (timer && timer->card && !try_module_get(timer->card->module)) {
+        if (timer && !try_module_get(timer->module)) {
                 kfree(timeri->owner);
                 kfree(timeri);
                 return NULL;
@@ -363,8 +363,8 @@ int snd_timer_close(snd_timer_instance_t * timeri)
                 timeri->private_free(timeri);
         kfree(timeri->owner);
         kfree(timeri);
-        if (timer && timer->card)
-                module_put(timer->card->module);
+        if (timer)
+                module_put(timer->module);
         return 0;
 }
 
@@ -787,6 +787,7 @@ int snd_timer_new(snd_card_t *card, char *id, snd_timer_id_t *tid, snd_timer_t *
         spin_lock_init(&timer->lock);
         tasklet_init(&timer->task_queue, snd_timer_tasklet, (unsigned long)timer);
         if (card != NULL) {
+                timer->module = card->module;
                 if ((err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops)) < 0) {
                         snd_timer_free(timer);
                         return err;