// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Functions for accessing OPL4 devices
 * Copyright (c) 2003 by Clemens Ladisch <clemens@ladisch.de>
 */

#include "opl4_local.h"
#include <sound/initval.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/io.h>

MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
MODULE_DESCRIPTION("OPL4 driver");
MODULE_LICENSE("GPL");

static inline void snd_opl4_wait(struct snd_opl4 *opl4)
{
	int timeout = 10;
	while ((inb(opl4->fm_port) & OPL4_STATUS_BUSY) && --timeout > 0)
		;
}

void snd_opl4_write(struct snd_opl4 *opl4, u8 reg, u8 value)
{
	snd_opl4_wait(opl4);
	outb(reg, opl4->pcm_port);

	snd_opl4_wait(opl4);
	outb(value, opl4->pcm_port + 1);
}

EXPORT_SYMBOL(snd_opl4_write);

u8 snd_opl4_read(struct snd_opl4 *opl4, u8 reg)
{
	snd_opl4_wait(opl4);
	outb(reg, opl4->pcm_port);

	snd_opl4_wait(opl4);
	return inb(opl4->pcm_port + 1);
}

EXPORT_SYMBOL(snd_opl4_read);

void snd_opl4_read_memory(struct snd_opl4 *opl4, char *buf, int offset, int size)
{
	unsigned long flags;
	u8 memcfg;

	spin_lock_irqsave(&opl4->reg_lock, flags);

	memcfg = snd_opl4_read(opl4, OPL4_REG_MEMORY_CONFIGURATION);
	snd_opl4_write(opl4, OPL4_REG_MEMORY_CONFIGURATION, memcfg | OPL4_MODE_BIT);

	snd_opl4_write(opl4, OPL4_REG_MEMORY_ADDRESS_HIGH, offset >> 16);
	snd_opl4_write(opl4, OPL4_REG_MEMORY_ADDRESS_MID, offset >> 8);
	snd_opl4_write(opl4, OPL4_REG_MEMORY_ADDRESS_LOW, offset);

	snd_opl4_wait(opl4);
	outb(OPL4_REG_MEMORY_DATA, opl4->pcm_port);
	snd_opl4_wait(opl4);
	insb(opl4->pcm_port + 1, buf, size);

	snd_opl4_write(opl4, OPL4_REG_MEMORY_CONFIGURATION, memcfg);

	spin_unlock_irqrestore(&opl4->reg_lock, flags);
}

EXPORT_SYMBOL(snd_opl4_read_memory);

void snd_opl4_write_memory(struct snd_opl4 *opl4, const char *buf, int offset, int size)
{
	unsigned long flags;
	u8 memcfg;

	spin_lock_irqsave(&opl4->reg_lock, flags);

	memcfg = snd_opl4_read(opl4, OPL4_REG_MEMORY_CONFIGURATION);
	snd_opl4_write(opl4, OPL4_REG_MEMORY_CONFIGURATION, memcfg | OPL4_MODE_BIT);

	snd_opl4_write(opl4, OPL4_REG_MEMORY_ADDRESS_HIGH, offset >> 16);
	snd_opl4_write(opl4, OPL4_REG_MEMORY_ADDRESS_MID, offset >> 8);
	snd_opl4_write(opl4, OPL4_REG_MEMORY_ADDRESS_LOW, offset);

	snd_opl4_wait(opl4);
	outb(OPL4_REG_MEMORY_DATA, opl4->pcm_port);
	snd_opl4_wait(opl4);
	outsb(opl4->pcm_port + 1, buf, size);

	snd_opl4_write(opl4, OPL4_REG_MEMORY_CONFIGURATION, memcfg);

	spin_unlock_irqrestore(&opl4->reg_lock, flags);
}

EXPORT_SYMBOL(snd_opl4_write_memory);

static void snd_opl4_enable_opl4(struct snd_opl4 *opl4)
{
	outb(OPL3_REG_MODE, opl4->fm_port + 2);
	inb(opl4->fm_port);
	inb(opl4->fm_port);
	outb(OPL3_OPL3_ENABLE | OPL3_OPL4_ENABLE, opl4->fm_port + 3);
	inb(opl4->fm_port);
	inb(opl4->fm_port);
}

static int snd_opl4_detect(struct snd_opl4 *opl4)
{
	u8 id1, id2;

	snd_opl4_enable_opl4(opl4);

	id1 = snd_opl4_read(opl4, OPL4_REG_MEMORY_CONFIGURATION);
	dev_dbg(opl4->card->dev, "OPL4[02]=%02x\n", id1);
	switch (id1 & OPL4_DEVICE_ID_MASK) {
	case 0x20:
		opl4->hardware = OPL3_HW_OPL4;
		break;
	case 0x40:
		opl4->hardware = OPL3_HW_OPL4_ML;
		break;
	default:
		return -ENODEV;
	}

	snd_opl4_write(opl4, OPL4_REG_MIX_CONTROL_FM, 0x00);
	snd_opl4_write(opl4, OPL4_REG_MIX_CONTROL_PCM, 0xff);
	id1 = snd_opl4_read(opl4, OPL4_REG_MIX_CONTROL_FM);
	id2 = snd_opl4_read(opl4, OPL4_REG_MIX_CONTROL_PCM);
	dev_dbg(opl4->card->dev, "OPL4 id1=%02x id2=%02x\n", id1, id2);
       	if (id1 != 0x00 || id2 != 0xff)
		return -ENODEV;

	snd_opl4_write(opl4, OPL4_REG_MIX_CONTROL_FM, 0x3f);
	snd_opl4_write(opl4, OPL4_REG_MIX_CONTROL_PCM, 0x3f);
	snd_opl4_write(opl4, OPL4_REG_MEMORY_CONFIGURATION, 0x00);
	return 0;
}

#if IS_ENABLED(CONFIG_SND_SEQUENCER)
static void snd_opl4_seq_dev_free(struct snd_seq_device *seq_dev)
{
	struct snd_opl4 *opl4 = seq_dev->private_data;
	opl4->seq_dev = NULL;
}

static int snd_opl4_create_seq_dev(struct snd_opl4 *opl4, int seq_device)
{
	opl4->seq_dev_num = seq_device;
	if (snd_seq_device_new(opl4->card, seq_device, SNDRV_SEQ_DEV_ID_OPL4,
			       sizeof(struct snd_opl4 *), &opl4->seq_dev) >= 0) {
		strcpy(opl4->seq_dev->name, "OPL4 Wavetable");
		*(struct snd_opl4 **)SNDRV_SEQ_DEVICE_ARGPTR(opl4->seq_dev) = opl4;
		opl4->seq_dev->private_data = opl4;
		opl4->seq_dev->private_free = snd_opl4_seq_dev_free;
	}
	return 0;
}
#endif

static void snd_opl4_free(struct snd_opl4 *opl4)
{
	snd_opl4_free_proc(opl4);
	release_and_free_resource(opl4->res_fm_port);
	release_and_free_resource(opl4->res_pcm_port);
	kfree(opl4);
}

static int snd_opl4_dev_free(struct snd_device *device)
{
	struct snd_opl4 *opl4 = device->device_data;
	snd_opl4_free(opl4);
	return 0;
}

int snd_opl4_create(struct snd_card *card,
		    unsigned long fm_port, unsigned long pcm_port,
		    int seq_device,
		    struct snd_opl3 **ropl3, struct snd_opl4 **ropl4)
{
	struct snd_opl4 *opl4;
	struct snd_opl3 *opl3;
	int err;
	static const struct snd_device_ops ops = {
		.dev_free = snd_opl4_dev_free
	};

	if (ropl3)
		*ropl3 = NULL;
	if (ropl4)
		*ropl4 = NULL;

	opl4 = kzalloc(sizeof(*opl4), GFP_KERNEL);
	if (!opl4)
		return -ENOMEM;

	opl4->res_fm_port = request_region(fm_port, 8, "OPL4 FM");
	opl4->res_pcm_port = request_region(pcm_port, 8, "OPL4 PCM/MIX");
	if (!opl4->res_fm_port || !opl4->res_pcm_port) {
		dev_err(card->dev, "opl4: can't grab ports 0x%lx, 0x%lx\n", fm_port, pcm_port);
		snd_opl4_free(opl4);
		return -EBUSY;
	}

	opl4->card = card;
	opl4->fm_port = fm_port;
	opl4->pcm_port = pcm_port;
	spin_lock_init(&opl4->reg_lock);
	mutex_init(&opl4->access_mutex);

	err = snd_opl4_detect(opl4);
	if (err < 0) {
		snd_opl4_free(opl4);
		dev_dbg(card->dev, "OPL4 chip not detected at %#lx/%#lx\n", fm_port, pcm_port);
		return err;
	}

	err = snd_device_new(card, SNDRV_DEV_CODEC, opl4, &ops);
	if (err < 0) {
		snd_opl4_free(opl4);
		return err;
	}

	err = snd_opl3_create(card, fm_port, fm_port + 2, opl4->hardware, 1, &opl3);
	if (err < 0) {
		snd_device_free(card, opl4);
		return err;
	}

	/* opl3 initialization disabled opl4, so reenable */
	snd_opl4_enable_opl4(opl4);

	snd_opl4_create_mixer(opl4);
	snd_opl4_create_proc(opl4);

#if IS_ENABLED(CONFIG_SND_SEQUENCER)
	opl4->seq_client = -1;
	if (opl4->hardware < OPL3_HW_OPL4_ML)
		snd_opl4_create_seq_dev(opl4, seq_device);
#endif

	if (ropl3)
		*ropl3 = opl3;
	if (ropl4)
		*ropl4 = opl4;
	return 0;
}

EXPORT_SYMBOL(snd_opl4_create);