/*
 *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
 *                   Uros Bizjak <uros@kss-loka.si>
 *
 *  Lowlevel routines for control of Sound Blaster cards
 *
 *   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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#define SNDRV_MAIN_OBJECT_FILE
#include <sound/driver.h>
#include <sound/sb.h>
#include <sound/initval.h>

MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
MODULE_DESCRIPTION("ALSA lowlevel driver for Sound Blaster cards");
MODULE_CLASSES("{sound}");

#define BUSY_LOOPS 100000

#undef IO_DEBUG

int snd_sbdsp_command(struct snd_sb *chip, unsigned char val)
{
    int i;
#ifdef IO_DEBUG
    snd_printk("command 0x%x\n", val);
#endif
    for (i = BUSY_LOOPS; i; i--)
        if ((inb(SBP(chip, STATUS)) & 0x80) == 0) {
            outb(val, SBP(chip, COMMAND));
            return 1;
        }
    snd_printd(__FUNCTION__ " [0x%lx]: timeout (0x%x)\n", chip->port, val);
    return 0;
}

int snd_sbdsp_get_byte(struct snd_sb *chip)
{
    int val;
    int i;
    for (i = BUSY_LOOPS; i; i--) {
        if (inb(SBP(chip, DATA_AVAIL)) & 0x80) {
            val = inb(SBP(chip, READ));
#ifdef IO_DEBUG
            snd_printk("get_byte 0x%x\n", val);
#endif
            return val;
        }
    }
    snd_printd(__FUNCTION__ " [0x%lx]: timeout\n", chip->port);
    return -ENODEV;
}

int snd_sbdsp_reset(struct snd_sb *chip)
{
    int i;

    outb(1, SBP(chip, RESET));
    udelay(10);
    outb(0, SBP(chip, RESET));
    udelay(30);
    for (i = BUSY_LOOPS; i; i--)
        if (inb(SBP(chip, DATA_AVAIL)) & 0x80) {
            if (inb(SBP(chip, READ)) == 0xaa)
                return 0;
            else
                break;
        }
    snd_printdd(__FUNCTION__ " [0x%lx] failed...\n", chip->port);
    return -ENODEV;
}

int snd_sbdsp_version(struct snd_sb * chip)
{
    unsigned int result = -ENODEV;

    snd_sbdsp_command(chip, SB_DSP_GET_VERSION);
    result = (short) snd_sbdsp_get_byte(chip) << 8;
    result |= (short) snd_sbdsp_get_byte(chip);
    return result;
}

static int snd_sbdsp_probe(struct snd_sb * chip)
{
    int version;
    int major, minor;
    char *str;
    unsigned long flags;

    /*
     *  initialization sequence
     */

    spin_lock_irqsave(&chip->reg_lock, flags);
    if (snd_sbdsp_reset(chip) < 0) {
        spin_unlock_irqrestore(&chip->reg_lock, flags);
        return -ENODEV;
    }
    version = snd_sbdsp_version(chip);
    if (version < 0) {
        spin_unlock_irqrestore(&chip->reg_lock, flags);
        return -ENODEV;
    }
    spin_unlock_irqrestore(&chip->reg_lock, flags);
    major = version >> 8;
    minor = version & 0xff;
    snd_printdd("SB [0x%lx]: DSP chip found, version = %i.%i\n",
                chip->port, major, minor);

    switch (chip->hardware) {
    case SB_HW_AUTO:
        switch (major) {
        case 1:
            chip->hardware = SB_HW_10;
            str = "1.0";
            break;
        case 2:
            if (minor) {
                chip->hardware = SB_HW_201;
                str = "2.01+";
            } else {
                chip->hardware = SB_HW_20;
                str = "2.0";
            }
            break;
        case 3:
            chip->hardware = SB_HW_PRO;
            str = "Pro";
            break;
        case 4:
            chip->hardware = SB_HW_16;
            str = "16";
            break;
        default:
            snd_printk("SB [0x%lx]: unknown DSP chip version %i.%i\n",
                       chip->port, major, minor);
            return -ENODEV;
        }
        break;
    case SB_HW_ALS100:
        str = "16 (ALS-100)";
        break;
    case SB_HW_ALS4000:
        str = "16 (ALS-4000)";
        break;
    default:
        return -ENODEV;
    }
    sprintf(chip->name, "Sound Blaster %s", str);
    chip->version = (major << 8) | minor;
    return 0;
}

static int snd_sbdsp_free(struct snd_sb *chip)
{
    if (chip->res_port)
        release_resource(chip->res_port);
    if (chip->irq >= 0)
        free_irq(chip->irq, (void *) chip);
    if (chip->dma8 >= 0) {
        disable_dma(chip->dma8);
        free_dma(chip->dma8);
    }
    if (chip->dma16 >= 0) {
        disable_dma(chip->dma16);
        free_dma(chip->dma16);
    }
    kfree(chip);
    return 0;
}

static int snd_sbdsp_dev_free(snd_device_t *device)
{
    struct snd_sb *chip = device->device_data;
    return snd_sbdsp_free(chip);
}

int snd_sbdsp_create(snd_card_t *card,
                     unsigned long port,
                     int irq,
                     irqreturn_t (*irq_handler)(int, void *, struct pt_regs *),
                     int dma8,
                     int dma16,
                     unsigned short hardware,
                     struct snd_sb **r_chip)
{
    struct snd_sb *chip;
    int err;
#ifdef TARGET_OS2
    static snd_device_ops_t ops = {
        snd_sbdsp_dev_free,0,0
    };
#else
    static snd_device_ops_t ops = {
    dev_free:       snd_sbdsp_dev_free,
    };
#endif

    snd_assert(r_chip != NULL, return -EINVAL);
    *r_chip = NULL;
    chip = kcalloc(1, sizeof(*chip), GFP_KERNEL);
    if (chip == NULL)
        return -ENOMEM;
    spin_lock_init(&chip->reg_lock);
    spin_lock_init(&chip->open_lock);
    spin_lock_init(&chip->midi_input_lock);
    spin_lock_init(&chip->mixer_lock);
    chip->irq = -1;
    chip->dma8 = -1;
    chip->dma16 = -1;
    chip->port = port;

    if (request_irq(irq, irq_handler, hardware == SB_HW_ALS4000 ?
                    SA_INTERRUPT | SA_SHIRQ : SA_INTERRUPT,
                    "SoundBlaster", (void *) chip)) {
        snd_sbdsp_free(chip);
        return -EBUSY;
    }
    chip->irq = irq;

    if (hardware == SB_HW_ALS4000)
        goto __skip_allocation;

    if ((chip->res_port = request_region(port, 16, "SoundBlaster")) == NULL) {
        snd_sbdsp_free(chip);
        return -EBUSY;
    }

    if (dma8 >= 0 && request_dma(dma8, "SoundBlaster - 8bit")) {
        snd_sbdsp_free(chip);
        return -EBUSY;
    }
    chip->dma8 = dma8;
    if (dma16 >= 0 && request_dma(dma16, "SoundBlaster - 16bit")) {
        snd_sbdsp_free(chip);
        return -EBUSY;
    }
    chip->dma16 = dma16;

__skip_allocation:
    chip->card = card;
    chip->hardware = hardware;
    if ((err = snd_sbdsp_probe(chip)) < 0) {
        snd_sbdsp_free(chip);
        return err;
    }
    if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
        snd_sbdsp_free(chip);
        return err;
    }
    *r_chip = chip;
    return 0;
}

EXPORT_SYMBOL(snd_sbdsp_command);
EXPORT_SYMBOL(snd_sbdsp_get_byte);
EXPORT_SYMBOL(snd_sbdsp_reset);
EXPORT_SYMBOL(snd_sbdsp_create);
/* sb_mixer.c */
EXPORT_SYMBOL(snd_sbmixer_write);
EXPORT_SYMBOL(snd_sbmixer_read);
EXPORT_SYMBOL(snd_sbmixer_new);

/*
 *  INIT part
 */

static int __init alsa_sb_common_init(void)
{
    return 0;
}

static void __exit alsa_sb_common_exit(void)
{
}

module_init(alsa_sb_common_init)
module_exit(alsa_sb_common_exit)
