1 /* 2 * Copyright (c) by Lee Revell <rlrevell@joe-job.com> 3 * Clemens Ladisch <clemens@ladisch.de> 4 * Routines for control of EMU10K1 chips 5 * 6 * BUGS: 7 * -- 8 * 9 * TODO: 10 * -- 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation; either version 2 of the License, or 15 * (at your option) any later version. 16 * 17 * This program is distributed in the hope that it will be useful, 18 * but WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 20 * GNU General Public License for more details. 21 * 22 * You should have received a copy of the GNU General Public License 23 * along with this program; if not, write to the Free Software 24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 25 * 26 */ 27 28 #include <sound/driver.h> 29 #include <linux/time.h> 30 #include <sound/core.h> 31 #include <sound/emu10k1.h> 32 33 static int snd_emu10k1_timer_start(struct snd_timer *timer) 34 { 35 struct snd_emu10k1 *emu; 36 unsigned long flags; 37 unsigned int delay; 38 39 emu = snd_timer_chip(timer); 40 delay = timer->sticks - 1; 41 if (delay < 5 ) /* minimum time is 5 ticks */ 42 delay = 5; 43 spin_lock_irqsave(&emu->reg_lock, flags); 44 snd_emu10k1_intr_enable(emu, INTE_INTERVALTIMERENB); 45 outw(delay & TIMER_RATE_MASK, emu->port + TIMER); 46 spin_unlock_irqrestore(&emu->reg_lock, flags); 47 return 0; 48 } 49 50 static int snd_emu10k1_timer_stop(struct snd_timer *timer) 51 { 52 struct snd_emu10k1 *emu; 53 unsigned long flags; 54 55 emu = snd_timer_chip(timer); 56 spin_lock_irqsave(&emu->reg_lock, flags); 57 snd_emu10k1_intr_disable(emu, INTE_INTERVALTIMERENB); 58 spin_unlock_irqrestore(&emu->reg_lock, flags); 59 return 0; 60 } 61 62 static int snd_emu10k1_timer_precise_resolution(struct snd_timer *timer, 63 unsigned long *num, unsigned long *den) 64 { 65 *num = 1; 66 *den = 48000; 67 return 0; 68 } 69 70 static struct snd_timer_hardware snd_emu10k1_timer_hw = { 71 .flags = SNDRV_TIMER_HW_AUTO, 72 .resolution = 20833, /* 1 sample @ 48KHZ = 20.833...us */ 73 .ticks = 1024, 74 .start = snd_emu10k1_timer_start, 75 .stop = snd_emu10k1_timer_stop, 76 .precise_resolution = snd_emu10k1_timer_precise_resolution, 77 }; 78 79 int __devinit snd_emu10k1_timer(struct snd_emu10k1 *emu, int device) 80 { 81 struct snd_timer *timer = NULL; 82 struct snd_timer_id tid; 83 int err; 84 85 tid.dev_class = SNDRV_TIMER_CLASS_CARD; 86 tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE; 87 tid.card = emu->card->number; 88 tid.device = device; 89 tid.subdevice = 0; 90 if ((err = snd_timer_new(emu->card, "EMU10K1", &tid, &timer)) >= 0) { 91 strcpy(timer->name, "EMU10K1 timer"); 92 timer->private_data = emu; 93 timer->hw = snd_emu10k1_timer_hw; 94 } 95 emu->timer = timer; 96 return err; 97 } 98