Commit ac5d1a7d authored by Clemens Ladisch's avatar Clemens Ladisch Committed by Jaroslav Kysela
Browse files

[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: default avatarClemens Ladisch <clemens@ladisch.de>
Signed-off-by: default avatarJaroslav Kysela <perex@suse.cz>
parent 2ea58144

sound/core/rtctimer.c

+14 −6
Original line number Diff line number Diff line
@@ -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) {