// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Routines for Gravis UltraSound soundcards - Timers
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *
 *  GUS have similar timers as AdLib (OPL2/OPL3 chips).
 */

#include <linux/time.h>
#include <sound/core.h>
#include <sound/gus.h>

/*
 *  Timer 1 - 80us
 */

static int snd_gf1_timer1_start(struct snd_timer * timer)
{
	unsigned long flags;
	unsigned char tmp;
	unsigned int ticks;
	struct snd_gus_card *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(struct snd_timer * timer)
{
	unsigned long flags;
	unsigned char tmp;
	struct snd_gus_card *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(struct snd_timer * timer)
{
	unsigned long flags;
	unsigned char tmp;
	unsigned int ticks;
	struct snd_gus_card *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(struct snd_timer * timer)
{
	unsigned long flags;
	unsigned char tmp;
	struct snd_gus_card *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(struct snd_gus_card * gus)
{
	struct snd_timer *timer = gus->gf1.timer1;

	if (timer == NULL)
		return;
	snd_timer_interrupt(timer, timer->sticks);
}

static void snd_gf1_interrupt_timer2(struct snd_gus_card * gus)
{
	struct snd_timer *timer = gus->gf1.timer2;

	if (timer == NULL)
		return;
	snd_timer_interrupt(timer, timer->sticks);
}

/*

 */

static const 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 const 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(struct snd_timer *timer)
{
	struct snd_gus_card *gus = timer->private_data;
	gus->gf1.timer1 = NULL;
}

static void snd_gf1_timer2_free(struct snd_timer *timer)
{
	struct snd_gus_card *gus = timer->private_data;
	gus->gf1.timer2 = NULL;
}

void snd_gf1_timers_init(struct snd_gus_card * gus)
{
	struct snd_timer *timer;
	struct snd_timer_id 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(struct snd_gus_card * 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;
	}
}

What is this?

You are looking at a code browser for Linux.

By using this web interface, you can navigate the source code of Linux by following simple links, search it by using the box in the navigation bar, or use vi inspired key bindings to move within files.

It should all be pretty intuitive, but to get started, here are a few things you may want to try:

This site was generated via sbexr, which uses LLVM and clang to parse and index the code.

sbexr is free software (as in "free speech"), under heavy development. sbexr.rabexc.org and the Linux kernel source code are used as a playground to test new features, observe bugs, and gather feedback. Check there often if you want to see new features in action.

As of today, the best way to know more about the project or participate in the development is to join the mailing list, and follow the project on github.