| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 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 <linux/time.h> |
| 29 | #include <sound/core.h> |
| 30 | #include <sound/emu10k1.h> |
| 31 | |
| 32 | static int snd_emu10k1_timer_start(struct snd_timer *timer) |
| 33 | { |
| 34 | struct snd_emu10k1 *emu; |
| 35 | unsigned long flags; |
| 36 | unsigned int delay; |
| 37 | |
| 38 | emu = snd_timer_chip(timer); |
| 39 | delay = timer->sticks - 1; |
| 40 | if (delay < 5 ) /* minimum time is 5 ticks */ |
| 41 | delay = 5; |
| 42 | spin_lock_irqsave(&emu->reg_lock, flags); |
| 43 | snd_emu10k1_intr_enable(emu, INTE_INTERVALTIMERENB); |
| 44 | outw(delay & TIMER_RATE_MASK, emu->port + TIMER); |
| 45 | spin_unlock_irqrestore(&emu->reg_lock, flags); |
| 46 | return 0; |
| 47 | } |
| 48 | |
| 49 | static int snd_emu10k1_timer_stop(struct snd_timer *timer) |
| 50 | { |
| 51 | struct snd_emu10k1 *emu; |
| 52 | unsigned long flags; |
| 53 | |
| 54 | emu = snd_timer_chip(timer); |
| 55 | spin_lock_irqsave(&emu->reg_lock, flags); |
| 56 | snd_emu10k1_intr_disable(emu, INTE_INTERVALTIMERENB); |
| 57 | spin_unlock_irqrestore(&emu->reg_lock, flags); |
| 58 | return 0; |
| 59 | } |
| 60 | |
| 61 | static int snd_emu10k1_timer_precise_resolution(struct snd_timer *timer, |
| 62 | unsigned long *num, unsigned long *den) |
| 63 | { |
| 64 | *num = 1; |
| 65 | *den = 48000; |
| 66 | return 0; |
| 67 | } |
| 68 | |
| 69 | static struct snd_timer_hardware snd_emu10k1_timer_hw = { |
| 70 | .flags = SNDRV_TIMER_HW_AUTO, |
| 71 | .resolution = 20833, /* 1 sample @ 48KHZ = 20.833...us */ |
| 72 | .ticks = 1024, |
| 73 | .start = snd_emu10k1_timer_start, |
| 74 | .stop = snd_emu10k1_timer_stop, |
| 75 | .precise_resolution = snd_emu10k1_timer_precise_resolution, |
| 76 | }; |
| 77 | |
| 78 | int snd_emu10k1_timer(struct snd_emu10k1 *emu, int device) |
| 79 | { |
| 80 | struct snd_timer *timer = NULL; |
| 81 | struct snd_timer_id tid; |
| 82 | int err; |
| 83 | |
| 84 | tid.dev_class = SNDRV_TIMER_CLASS_CARD; |
| 85 | tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE; |
| 86 | tid.card = emu->card->number; |
| 87 | tid.device = device; |
| 88 | tid.subdevice = 0; |
| 89 | if ((err = snd_timer_new(emu->card, "EMU10K1", &tid, &timer)) >= 0) { |
| 90 | strcpy(timer->name, "EMU10K1 timer"); |
| 91 | timer->private_data = emu; |
| 92 | timer->hw = snd_emu10k1_timer_hw; |
| 93 | } |
| 94 | emu->timer = timer; |
| 95 | return err; |
| 96 | } |