--- /dev/null
-       stime->hrt.cb_mode = HRTIMER_CB_IRQSAFE_UNLOCKED;
 +/*
 + * ALSA timer back-end using hrtimer
 + * Copyright (C) 2008 Takashi Iwai
 + *
 + *   This program is free software; you can redistribute it and/or modify
 + *   it under the terms of the GNU General Public License as published by
 + *   the Free Software Foundation; either version 2 of the License, or
 + *   (at your option) any later version.
 + *
 + *   This program is distributed in the hope that it will be useful,
 + *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 + *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 + *   GNU General Public License for more details.
 + *
 + *   You should have received a copy of the GNU General Public License
 + *   along with this program; if not, write to the Free Software
 + *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 + *
 + */
 +
 +#include <linux/init.h>
 +#include <linux/module.h>
 +#include <linux/moduleparam.h>
 +#include <linux/hrtimer.h>
 +#include <sound/core.h>
 +#include <sound/timer.h>
 +
 +MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
 +MODULE_DESCRIPTION("ALSA hrtimer backend");
 +MODULE_LICENSE("GPL");
 +
 +MODULE_ALIAS("snd-timer-" __stringify(SNDRV_TIMER_GLOBAL_HRTIMER));
 +
 +#define NANO_SEC      1000000000UL    /* 10^9 in sec */
 +static unsigned int resolution;
 +
 +struct snd_hrtimer {
 +      struct snd_timer *timer;
 +      struct hrtimer hrt;
 +};
 +
 +static enum hrtimer_restart snd_hrtimer_callback(struct hrtimer *hrt)
 +{
 +      struct snd_hrtimer *stime = container_of(hrt, struct snd_hrtimer, hrt);
 +      struct snd_timer *t = stime->timer;
 +      hrtimer_forward_now(hrt, ns_to_ktime(t->sticks * resolution));
 +      snd_timer_interrupt(stime->timer, t->sticks);
 +      return HRTIMER_RESTART;
 +}
 +
 +static int snd_hrtimer_open(struct snd_timer *t)
 +{
 +      struct snd_hrtimer *stime;
 +
 +      stime = kmalloc(sizeof(*stime), GFP_KERNEL);
 +      if (!stime)
 +              return -ENOMEM;
 +      hrtimer_init(&stime->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 +      stime->timer = t;
 +      stime->hrt.function = snd_hrtimer_callback;
 +      t->private_data = stime;
 +      return 0;
 +}
 +
 +static int snd_hrtimer_close(struct snd_timer *t)
 +{
 +      struct snd_hrtimer *stime = t->private_data;
 +
 +      if (stime) {
 +              hrtimer_cancel(&stime->hrt);
 +              kfree(stime);
 +              t->private_data = NULL;
 +      }
 +      return 0;
 +}
 +
 +static int snd_hrtimer_start(struct snd_timer *t)
 +{
 +      struct snd_hrtimer *stime = t->private_data;
 +
 +      hrtimer_start(&stime->hrt, ns_to_ktime(t->sticks * resolution),
 +                    HRTIMER_MODE_REL);
 +      return 0;
 +}
 +
 +static int snd_hrtimer_stop(struct snd_timer *t)
 +{
 +      struct snd_hrtimer *stime = t->private_data;
 +
 +      hrtimer_cancel(&stime->hrt);
 +      return 0;
 +}
 +
 +static struct snd_timer_hardware hrtimer_hw = {
 +      .flags =        SNDRV_TIMER_HW_AUTO,
 +      .open =         snd_hrtimer_open,
 +      .close =        snd_hrtimer_close,
 +      .start =        snd_hrtimer_start,
 +      .stop =         snd_hrtimer_stop,
 +};
 +
 +/*
 + * entry functions
 + */
 +
 +static struct snd_timer *mytimer;
 +
 +static int __init snd_hrtimer_init(void)
 +{
 +      struct snd_timer *timer;
 +      struct timespec tp;
 +      int err;
 +
 +      hrtimer_get_res(CLOCK_MONOTONIC, &tp);
 +      if (tp.tv_sec > 0 || !tp.tv_nsec) {
 +              snd_printk(KERN_ERR
 +                         "snd-hrtimer: Invalid resolution %u.%09u",
 +                         (unsigned)tp.tv_sec, (unsigned)tp.tv_nsec);
 +              return -EINVAL;
 +      }
 +      resolution = tp.tv_nsec;
 +
 +      /* Create a new timer and set up the fields */
 +      err = snd_timer_global_new("hrtimer", SNDRV_TIMER_GLOBAL_HRTIMER,
 +                                 &timer);
 +      if (err < 0)
 +              return err;
 +
 +      timer->module = THIS_MODULE;
 +      strcpy(timer->name, "HR timer");
 +      timer->hw = hrtimer_hw;
 +      timer->hw.resolution = resolution;
 +      timer->hw.ticks = NANO_SEC / resolution;
 +
 +      err = snd_timer_global_register(timer);
 +      if (err < 0) {
 +              snd_timer_global_free(timer);
 +              return err;
 +      }
 +      mytimer = timer; /* remember this */
 +
 +      return 0;
 +}
 +
 +static void __exit snd_hrtimer_exit(void)
 +{
 +      if (mytimer) {
 +              snd_timer_global_free(mytimer);
 +              mytimer = NULL;
 +      }
 +}
 +
 +module_init(snd_hrtimer_init);
 +module_exit(snd_hrtimer_exit);