/*
   *  Copyright (c) by Lee Revell <rlrevell@joe-job.com>
   *                   Clemens Ladisch <clemens@ladisch.de>
   *  Routines for control of EMU10K1 chips
   *
   *  BUGS:
   *    --
   *
   *  TODO:
   *    --
   *
   *   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/time.h>
  #include <sound/core.h>
  #include <sound/emu10k1.h>

  static int snd_emu10k1_timer_start(struct snd_timer *timer)

  {

  	struct snd_emu10k1 *emu;

  	unsigned long flags;
  	unsigned int delay;
  
  	emu = snd_timer_chip(timer);
  	delay = timer->sticks - 1;
  	if (delay < 5 ) /* minimum time is 5 ticks */
  		delay = 5;
  	spin_lock_irqsave(&emu->reg_lock, flags);
  	snd_emu10k1_intr_enable(emu, INTE_INTERVALTIMERENB);
  	outw(delay & TIMER_RATE_MASK, emu->port + TIMER);
  	spin_unlock_irqrestore(&emu->reg_lock, flags);
  	return 0;
  }

  static int snd_emu10k1_timer_stop(struct snd_timer *timer)

  {

  	struct snd_emu10k1 *emu;

  	unsigned long flags;
  
  	emu = snd_timer_chip(timer);
  	spin_lock_irqsave(&emu->reg_lock, flags);
  	snd_emu10k1_intr_disable(emu, INTE_INTERVALTIMERENB);
  	spin_unlock_irqrestore(&emu->reg_lock, flags);
  	return 0;
  }

  static int snd_emu10k1_timer_precise_resolution(struct snd_timer *timer,

  					       unsigned long *num, unsigned long *den)
  {
  	*num = 1;
  	*den = 48000;
  	return 0;
  }

  static struct snd_timer_hardware snd_emu10k1_timer_hw = {

  	.flags = SNDRV_TIMER_HW_AUTO,
  	.resolution = 20833, /* 1 sample @ 48KHZ = 20.833...us */
  	.ticks = 1024,
  	.start = snd_emu10k1_timer_start,
  	.stop = snd_emu10k1_timer_stop,
  	.precise_resolution = snd_emu10k1_timer_precise_resolution,
  };

  int __devinit snd_emu10k1_timer(struct snd_emu10k1 *emu, int device)

  {

  	struct snd_timer *timer = NULL;
  	struct snd_timer_id tid;

  	int err;
  
  	tid.dev_class = SNDRV_TIMER_CLASS_CARD;
  	tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
  	tid.card = emu->card->number;
  	tid.device = device;
  	tid.subdevice = 0;
  	if ((err = snd_timer_new(emu->card, "EMU10K1", &tid, &timer)) >= 0) {
  		strcpy(timer->name, "EMU10K1 timer");
  		timer->private_data = emu;
  		timer->hw = snd_emu10k1_timer_hw;
  	}
  	emu->timer = timer;
  	return err;
  }