📄 gus_timer.c
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/* * Routines for Gravis UltraSound soundcards - Timers * Copyright (c) by Jaroslav Kysela <perex@suse.cz> * * GUS have similar timers as AdLib (OPL2/OPL3 chips). * * * 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 <sound/driver.h>#include <linux/time.h>#include <sound/core.h>#include <sound/gus.h>/* * Timer 1 - 80us */static int snd_gf1_timer1_start(snd_timer_t * timer){ unsigned long flags; unsigned char tmp; unsigned int ticks; snd_gus_card_t *gus; gus = snd_timer_chip(timer); spin_lock_irqsave(&gus->reg_lock, flags); ticks = timer->sticks; tmp = (gus->gf1.timer_enabled |= 4); snd_gf1_write8(gus, SNDRV_GF1_GB_ADLIB_TIMER_1, 256 - ticks); /* timer 1 count */ snd_gf1_write8(gus, SNDRV_GF1_GB_SOUND_BLASTER_CONTROL, tmp); /* enable timer 1 IRQ */ snd_gf1_adlib_write(gus, 0x04, tmp >> 2); /* timer 2 start */ spin_unlock_irqrestore(&gus->reg_lock, flags); return 0;}static int snd_gf1_timer1_stop(snd_timer_t * timer){ unsigned long flags; unsigned char tmp; snd_gus_card_t *gus; gus = snd_timer_chip(timer); spin_lock_irqsave(&gus->reg_lock, flags); tmp = (gus->gf1.timer_enabled &= ~4); snd_gf1_write8(gus, SNDRV_GF1_GB_SOUND_BLASTER_CONTROL, tmp); /* disable timer #1 */ spin_unlock_irqrestore(&gus->reg_lock, flags); return 0;}/* * Timer 2 - 320us */static int snd_gf1_timer2_start(snd_timer_t * timer){ unsigned long flags; unsigned char tmp; unsigned int ticks; snd_gus_card_t *gus; gus = snd_timer_chip(timer); spin_lock_irqsave(&gus->reg_lock, flags); ticks = timer->sticks; tmp = (gus->gf1.timer_enabled |= 8); snd_gf1_write8(gus, SNDRV_GF1_GB_ADLIB_TIMER_2, 256 - ticks); /* timer 2 count */ snd_gf1_write8(gus, SNDRV_GF1_GB_SOUND_BLASTER_CONTROL, tmp); /* enable timer 2 IRQ */ snd_gf1_adlib_write(gus, 0x04, tmp >> 2); /* timer 2 start */ spin_unlock_irqrestore(&gus->reg_lock, flags); return 0;}static int snd_gf1_timer2_stop(snd_timer_t * timer){ unsigned long flags; unsigned char tmp; snd_gus_card_t *gus; gus = snd_timer_chip(timer); spin_lock_irqsave(&gus->reg_lock, flags); tmp = (gus->gf1.timer_enabled &= ~8); snd_gf1_write8(gus, SNDRV_GF1_GB_SOUND_BLASTER_CONTROL, tmp); /* disable timer #1 */ spin_unlock_irqrestore(&gus->reg_lock, flags); return 0;}/* */static void snd_gf1_interrupt_timer1(snd_gus_card_t * gus){ snd_timer_t *timer = gus->gf1.timer1; if (timer == NULL) return; snd_timer_interrupt(timer, timer->sticks);}static void snd_gf1_interrupt_timer2(snd_gus_card_t * gus){ snd_timer_t *timer = gus->gf1.timer2; if (timer == NULL) return; snd_timer_interrupt(timer, timer->sticks);}/* */static struct _snd_timer_hardware snd_gf1_timer1 ={ .flags = SNDRV_TIMER_HW_STOP, .resolution = 80000, .ticks = 256, .start = snd_gf1_timer1_start, .stop = snd_gf1_timer1_stop,};static struct _snd_timer_hardware snd_gf1_timer2 ={ .flags = SNDRV_TIMER_HW_STOP, .resolution = 320000, .ticks = 256, .start = snd_gf1_timer2_start, .stop = snd_gf1_timer2_stop,};static void snd_gf1_timer1_free(snd_timer_t *timer){ snd_gus_card_t *gus = timer->private_data; gus->gf1.timer1 = NULL;}static void snd_gf1_timer2_free(snd_timer_t *timer){ snd_gus_card_t *gus = timer->private_data; gus->gf1.timer2 = NULL;}void snd_gf1_timers_init(snd_gus_card_t * gus){ snd_timer_t *timer; snd_timer_id_t tid; if (gus->gf1.timer1 != NULL || gus->gf1.timer2 != NULL) return; gus->gf1.interrupt_handler_timer1 = snd_gf1_interrupt_timer1; gus->gf1.interrupt_handler_timer2 = snd_gf1_interrupt_timer2; tid.dev_class = SNDRV_TIMER_CLASS_CARD; tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE; tid.card = gus->card->number; tid.device = gus->timer_dev; tid.subdevice = 0; if (snd_timer_new(gus->card, "GF1 timer", &tid, &timer) >= 0) { strcpy(timer->name, "GF1 timer #1"); timer->private_data = gus; timer->private_free = snd_gf1_timer1_free; timer->hw = snd_gf1_timer1; } gus->gf1.timer1 = timer; tid.device++; if (snd_timer_new(gus->card, "GF1 timer", &tid, &timer) >= 0) { strcpy(timer->name, "GF1 timer #2"); timer->private_data = gus; timer->private_free = snd_gf1_timer2_free; timer->hw = snd_gf1_timer2; } gus->gf1.timer2 = timer;}void snd_gf1_timers_done(snd_gus_card_t * gus){ snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_TIMER1 | SNDRV_GF1_HANDLER_TIMER2); if (gus->gf1.timer1) { snd_device_free(gus->card, gus->gf1.timer1); gus->gf1.timer1 = NULL; } if (gus->gf1.timer2) { snd_device_free(gus->card, gus->gf1.timer2); gus->gf1.timer2 = NULL; }}
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