root/sound/isa/sb/sb_common.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *                   Uros Bizjak <uros@kss-loka.si>
 *
 *  Lowlevel routines for control of Sound Blaster cards
 */

#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/io.h>
#include <sound/core.h>
#include <sound/sb.h>
#include <sound/initval.h>

#include <asm/dma.h>

MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
MODULE_DESCRIPTION("ALSA lowlevel driver for Sound Blaster cards");
MODULE_LICENSE("GPL");

#define BUSY_LOOPS 100000

#undef IO_DEBUG

int snd_sbdsp_command(struct snd_sb *chip, unsigned char val)
{
        int i;
#ifdef IO_DEBUG
        dev_dbg(chip->card->dev, "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;
                }
        dev_dbg(chip->card->dev, "%s [0x%lx]: timeout (0x%x)\n", __func__, 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
                        dev_dbg(chip->card->dev, "get_byte 0x%x\n", val);
#endif
                        return val;
                }
        }
        dev_dbg(chip->card->dev, "%s [0x%lx]: timeout\n", __func__, 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;
                }
        if (chip->card)
                dev_dbg(chip->card->dev, "%s [0x%lx] failed...\n", __func__, chip->port);
        return -ENODEV;
}

static int snd_sbdsp_version(struct snd_sb * chip)
{
        unsigned int result;

        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;

        /*
         *  initialization sequence
         */

        scoped_guard(spinlock_irqsave, &chip->reg_lock) {
                if (snd_sbdsp_reset(chip) < 0)
                        return -ENODEV;
                version = snd_sbdsp_version(chip);
                if (version < 0)
                        return -ENODEV;
        }
        major = version >> 8;
        minor = version & 0xff;
        dev_dbg(chip->card->dev, "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:
                        dev_info(chip->card->dev, "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;
        case SB_HW_DT019X:
                str = "(DT019X/ALS007)";
                break;
        case SB_HW_CS5530:
                str = "16 (CS5530)";
                break;
        case SB_HW_JAZZ16:
                str = "Pro (Jazz16)";
                break;
        default:
                return -ENODEV;
        }
        sprintf(chip->name, "Sound Blaster %s", str);
        chip->version = (major << 8) | minor;
        return 0;
}

int snd_sbdsp_create(struct snd_card *card,
                     unsigned long port,
                     int irq,
                     irq_handler_t irq_handler,
                     int dma8,
                     int dma16,
                     unsigned short hardware,
                     struct snd_sb **r_chip)
{
        struct snd_sb *chip;
        int err;

        if (snd_BUG_ON(!r_chip))
                return -EINVAL;
        *r_chip = NULL;
        chip = devm_kzalloc(card->dev, sizeof(*chip), GFP_KERNEL);
        if (!chip)
                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 (devm_request_irq(card->dev, irq, irq_handler,
                             (hardware == SB_HW_ALS4000 ||
                              hardware == SB_HW_CS5530) ?
                             IRQF_SHARED : 0,
                             "SoundBlaster", (void *) chip)) {
                dev_err(card->dev, "sb: can't grab irq %d\n", irq);
                return -EBUSY;
        }
        chip->irq = irq;
        card->sync_irq = chip->irq;

        if (hardware == SB_HW_ALS4000)
                goto __skip_allocation;
        
        chip->res_port = devm_request_region(card->dev, port, 16,
                                             "SoundBlaster");
        if (!chip->res_port) {
                dev_err(card->dev, "sb: can't grab port 0x%lx\n", port);
                return -EBUSY;
        }

#ifdef CONFIG_ISA
        if (dma8 >= 0 && snd_devm_request_dma(card->dev, dma8,
                                              "SoundBlaster - 8bit")) {
                dev_err(card->dev, "sb: can't grab DMA8 %d\n", dma8);
                return -EBUSY;
        }
        chip->dma8 = dma8;
        if (dma16 >= 0) {
                if (hardware != SB_HW_ALS100 && (dma16 < 5 || dma16 > 7)) {
                        /* no duplex */
                        dma16 = -1;
                } else if (snd_devm_request_dma(card->dev, dma16,
                                                "SoundBlaster - 16bit")) {
                        dev_err(card->dev, "sb: can't grab DMA16 %d\n", dma16);
                        return -EBUSY;
                }
        }
        chip->dma16 = dma16;
#endif

      __skip_allocation:
        chip->card = card;
        chip->hardware = hardware;
        err = snd_sbdsp_probe(chip);
        if (err < 0)
                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);
EXPORT_SYMBOL(snd_sbmixer_add_ctl);
#ifdef CONFIG_PM
EXPORT_SYMBOL(snd_sbmixer_suspend);
EXPORT_SYMBOL(snd_sbmixer_resume);
#endif