[ALSA] rtctimer: handle RTC interrupts with a tasklet

The calls to rtc_control() from inside the interrupt handler can upset
the RTC code, so move our interrupt handling code to a tasklet.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
This commit is contained in:
Clemens Ladisch 2006-10-27 10:45:00 +02:00 committed by Jaroslav Kysela
parent 2ea5814472
commit ac5d1a7d25

View file

@ -22,13 +22,10 @@
#include <sound/driver.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/threads.h>
#include <linux/interrupt.h>
#include <linux/moduleparam.h>
#include <sound/core.h>
#include <sound/timer.h>
#include <sound/info.h>
#if defined(CONFIG_RTC) || defined(CONFIG_RTC_MODULE)
@ -50,7 +47,9 @@ static int rtctimer_stop(struct snd_timer *t);
* The hardware dependent description for this timer.
*/
static struct snd_timer_hardware rtc_hw = {
.flags = SNDRV_TIMER_HW_FIRST|SNDRV_TIMER_HW_AUTO,
.flags = SNDRV_TIMER_HW_AUTO |
SNDRV_TIMER_HW_FIRST |
SNDRV_TIMER_HW_TASKLET,
.ticks = 100000000L, /* FIXME: XXX */
.open = rtctimer_open,
.close = rtctimer_close,
@ -60,6 +59,7 @@ static struct snd_timer_hardware rtc_hw = {
static int rtctimer_freq = RTC_FREQ; /* frequency */
static struct snd_timer *rtctimer;
static struct tasklet_struct rtc_tasklet;
static rtc_task_t rtc_task;
@ -81,6 +81,7 @@ rtctimer_close(struct snd_timer *t)
rtc_task_t *rtc = t->private_data;
if (rtc) {
rtc_unregister(rtc);
tasklet_kill(&rtc_tasklet);
t->private_data = NULL;
}
return 0;
@ -105,12 +106,17 @@ rtctimer_stop(struct snd_timer *timer)
return 0;
}
static void rtctimer_tasklet(unsigned long data)
{
snd_timer_interrupt((struct snd_timer *)data, 1);
}
/*
* interrupt
*/
static void rtctimer_interrupt(void *private_data)
{
snd_timer_interrupt(private_data, 1);
tasklet_hi_schedule(private_data);
}
@ -139,9 +145,11 @@ static int __init rtctimer_init(void)
timer->hw = rtc_hw;
timer->hw.resolution = NANO_SEC / rtctimer_freq;
tasklet_init(&rtc_tasklet, rtctimer_tasklet, (unsigned long)timer);
/* set up RTC callback */
rtc_task.func = rtctimer_interrupt;
rtc_task.private_data = timer;
rtc_task.private_data = &rtc_tasklet;
err = snd_timer_global_register(timer);
if (err < 0) {