// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *   Low-level ALSA driver for the ENSONIQ SoundScape
 *   Copyright (c) by Chris Rankin
 *
 *   This driver was written in part using information obtained from
 *   the OSS/Free SoundScape driver, written by Hannu Savolainen.
 */

#include <linux/init.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/isa.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/pnp.h>
#include <linux/spinlock.h>
#include <linux/module.h>
#include <asm/dma.h>
#include <sound/core.h>
#include <sound/wss.h>
#include <sound/mpu401.h>
#include <sound/initval.h>


MODULE_AUTHOR("Chris Rankin");
MODULE_DESCRIPTION("ENSONIQ SoundScape driver");
MODULE_LICENSE("GPL");
MODULE_FIRMWARE("sndscape.co0");
MODULE_FIRMWARE("sndscape.co1");
MODULE_FIRMWARE("sndscape.co2");
MODULE_FIRMWARE("sndscape.co3");
MODULE_FIRMWARE("sndscape.co4");
MODULE_FIRMWARE("scope.cod");

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
static char* id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;
static long port[SNDRV_CARDS] = SNDRV_DEFAULT_PORT;
static long wss_port[SNDRV_CARDS] = SNDRV_DEFAULT_PORT;
static int irq[SNDRV_CARDS] = SNDRV_DEFAULT_IRQ;
static int mpu_irq[SNDRV_CARDS] = SNDRV_DEFAULT_IRQ;
static int dma[SNDRV_CARDS] = SNDRV_DEFAULT_DMA;
static int dma2[SNDRV_CARDS] = SNDRV_DEFAULT_DMA;
static bool joystick[SNDRV_CARDS];

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index number for SoundScape soundcard");

module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "Description for SoundScape card");

module_param_hw_array(port, long, ioport, NULL, 0444);
MODULE_PARM_DESC(port, "Port # for SoundScape driver.");

module_param_hw_array(wss_port, long, ioport, NULL, 0444);
MODULE_PARM_DESC(wss_port, "WSS Port # for SoundScape driver.");

module_param_hw_array(irq, int, irq, NULL, 0444);
MODULE_PARM_DESC(irq, "IRQ # for SoundScape driver.");

module_param_hw_array(mpu_irq, int, irq, NULL, 0444);
MODULE_PARM_DESC(mpu_irq, "MPU401 IRQ # for SoundScape driver.");

module_param_hw_array(dma, int, dma, NULL, 0444);
MODULE_PARM_DESC(dma, "DMA # for SoundScape driver.");

module_param_hw_array(dma2, int, dma, NULL, 0444);
MODULE_PARM_DESC(dma2, "DMA2 # for SoundScape driver.");

module_param_array(joystick, bool, NULL, 0444);
MODULE_PARM_DESC(joystick, "Enable gameport.");

#ifdef CONFIG_PNP
static int isa_registered;
static int pnp_registered;

static const struct pnp_card_device_id sscape_pnpids[] = {
        { .id = "ENS3081", .devs = { { "ENS0000" } } }, /* Soundscape PnP */
        { .id = "ENS4081", .devs = { { "ENS1011" } } }, /* VIVO90 */
        { .id = "" }    /* end */
};

MODULE_DEVICE_TABLE(pnp_card, sscape_pnpids);
#endif


#define HOST_CTRL_IO(i)  ((i) + 2)
#define HOST_DATA_IO(i)  ((i) + 3)
#define ODIE_ADDR_IO(i)  ((i) + 4)
#define ODIE_DATA_IO(i)  ((i) + 5)
#define CODEC_IO(i)      ((i) + 8)

#define IC_ODIE  1
#define IC_OPUS  2

#define RX_READY 0x01
#define TX_READY 0x02

#define CMD_ACK                 0x80
#define CMD_SET_MIDI_VOL        0x84
#define CMD_GET_MIDI_VOL        0x85
#define CMD_XXX_MIDI_VOL        0x86
#define CMD_SET_EXTMIDI         0x8a
#define CMD_GET_EXTMIDI         0x8b
#define CMD_SET_MT32            0x8c
#define CMD_GET_MT32            0x8d

enum GA_REG {
        GA_INTSTAT_REG = 0,
        GA_INTENA_REG,
        GA_DMAA_REG,
        GA_DMAB_REG,
        GA_INTCFG_REG,
        GA_DMACFG_REG,
        GA_CDCFG_REG,
        GA_SMCFGA_REG,
        GA_SMCFGB_REG,
        GA_HMCTL_REG
};

#define DMA_8BIT  0x80


enum card_type {
        MEDIA_FX,       /* Sequoia S-1000 */
        SSCAPE,         /* Sequoia S-2000 */
        SSCAPE_PNP,
        SSCAPE_VIVO,
};

struct soundscape {
        spinlock_t lock;
        unsigned io_base;
        int ic_type;
        enum card_type type;
        struct resource *io_res;
        struct resource *wss_res;
        struct snd_wss *chip;

        unsigned char midi_vol;
};

#define INVALID_IRQ  ((unsigned)-1)


static inline struct soundscape *get_card_soundscape(struct snd_card *c)
{
        return (struct soundscape *) (c->private_data);
}

/*
 * Allocates some kernel memory that we can use for DMA.
 * I think this means that the memory has to map to
 * contiguous pages of physical memory.
 */
static struct snd_dma_buffer *get_dmabuf(struct soundscape *s,
                                         struct snd_dma_buffer *buf,
                                         unsigned long size)
{
        if (buf) {
                if (snd_dma_alloc_pages_fallback(SNDRV_DMA_TYPE_DEV,
                                                 s->chip->card->dev,
                                                 size, buf) < 0) {
                        snd_printk(KERN_ERR "sscape: Failed to allocate "
                                            "%lu bytes for DMA\n",
                                            size);
                        return NULL;
                }
        }

        return buf;
}

/*
 * Release the DMA-able kernel memory ...
 */
static void free_dmabuf(struct snd_dma_buffer *buf)
{
        if (buf && buf->area)
                snd_dma_free_pages(buf);
}

/*
 * This function writes to the SoundScape's control registers,
 * but doesn't do any locking. It's up to the caller to do that.
 * This is why this function is "unsafe" ...
 */
static inline void sscape_write_unsafe(unsigned io_base, enum GA_REG reg,
                                       unsigned char val)
{
        outb(reg, ODIE_ADDR_IO(io_base));
        outb(val, ODIE_DATA_IO(io_base));
}

/*
 * Write to the SoundScape's control registers, and do the
 * necessary locking ...
 */
static void sscape_write(struct soundscape *s, enum GA_REG reg,
                         unsigned char val)
{
        unsigned long flags;

        spin_lock_irqsave(&s->lock, flags);
        sscape_write_unsafe(s->io_base, reg, val);
        spin_unlock_irqrestore(&s->lock, flags);
}

/*
 * Read from the SoundScape's control registers, but leave any
 * locking to the caller. This is why the function is "unsafe" ...
 */
static inline unsigned char sscape_read_unsafe(unsigned io_base,
                                               enum GA_REG reg)
{
        outb(reg, ODIE_ADDR_IO(io_base));
        return inb(ODIE_DATA_IO(io_base));
}

/*
 * Puts the SoundScape into "host" mode, as compared to "MIDI" mode
 */
static inline void set_host_mode_unsafe(unsigned io_base)
{
        outb(0x0, HOST_CTRL_IO(io_base));
}

/*
 * Puts the SoundScape into "MIDI" mode, as compared to "host" mode
 */
static inline void set_midi_mode_unsafe(unsigned io_base)
{
        outb(0x3, HOST_CTRL_IO(io_base));
}

/*
 * Read the SoundScape's host-mode control register, but leave
 * any locking issues to the caller ...
 */
static inline int host_read_unsafe(unsigned io_base)
{
        int data = -1;
        if ((inb(HOST_CTRL_IO(io_base)) & RX_READY) != 0)
                data = inb(HOST_DATA_IO(io_base));

        return data;
}

/*
 * Read the SoundScape's host-mode control register, performing
 * a limited amount of busy-waiting if the register isn't ready.
 * Also leaves all locking-issues to the caller ...
 */
static int host_read_ctrl_unsafe(unsigned io_base, unsigned timeout)
{
        int data;

        while (((data = host_read_unsafe(io_base)) < 0) && (timeout != 0)) {
                udelay(100);
                --timeout;
        } /* while */

        return data;
}

/*
 * Write to the SoundScape's host-mode control registers, but
 * leave any locking issues to the caller ...
 */
static inline int host_write_unsafe(unsigned io_base, unsigned char data)
{
        if ((inb(HOST_CTRL_IO(io_base)) & TX_READY) != 0) {
                outb(data, HOST_DATA_IO(io_base));
                return 1;
        }

        return 0;
}

/*
 * Write to the SoundScape's host-mode control registers, performing
 * a limited amount of busy-waiting if the register isn't ready.
 * Also leaves all locking-issues to the caller ...
 */
static int host_write_ctrl_unsafe(unsigned io_base, unsigned char data,
                                  unsigned timeout)
{
        int err;

        while (!(err = host_write_unsafe(io_base, data)) && (timeout != 0)) {
                udelay(100);
                --timeout;
        } /* while */

        return err;
}


/*
 * Check that the MIDI subsystem is operational. If it isn't,
 * then we will hang the computer if we try to use it ...
 *
 * NOTE: This check is based upon observation, not documentation.
 */
static inline int verify_mpu401(const struct snd_mpu401 *mpu)
{
        return ((inb(MPU401C(mpu)) & 0xc0) == 0x80);
}

/*
 * This is apparently the standard way to initialise an MPU-401
 */
static inline void initialise_mpu401(const struct snd_mpu401 *mpu)
{
        outb(0, MPU401D(mpu));
}

/*
 * Tell the SoundScape to activate the AD1845 chip (I think).
 * The AD1845 detection fails if we *don't* do this, so I
 * think that this is a good idea ...
 */
static void activate_ad1845_unsafe(unsigned io_base)
{
        unsigned char val = sscape_read_unsafe(io_base, GA_HMCTL_REG);
        sscape_write_unsafe(io_base, GA_HMCTL_REG, (val & 0xcf) | 0x10);
        sscape_write_unsafe(io_base, GA_CDCFG_REG, 0x80);
}

/*
 * Do the necessary ALSA-level cleanup to deallocate our driver ...
 */
static void soundscape_free(struct snd_card *c)
{
        struct soundscape *sscape = get_card_soundscape(c);
        release_and_free_resource(sscape->io_res);
        release_and_free_resource(sscape->wss_res);
        free_dma(sscape->chip->dma1);
}

/*
 * Tell the SoundScape to begin a DMA transfer using the given channel.
 * All locking issues are left to the caller.
 */
static void sscape_start_dma_unsafe(unsigned io_base, enum GA_REG reg)
{
        sscape_write_unsafe(io_base, reg,
                            sscape_read_unsafe(io_base, reg) | 0x01);
        sscape_write_unsafe(io_base, reg,
                            sscape_read_unsafe(io_base, reg) & 0xfe);
}

/*
 * Wait for a DMA transfer to complete. This is a "limited busy-wait",
 * and all locking issues are left to the caller.
 */
static int sscape_wait_dma_unsafe(unsigned io_base, enum GA_REG reg,
                                  unsigned timeout)
{
        while (!(sscape_read_unsafe(io_base, reg) & 0x01) && (timeout != 0)) {
                udelay(100);
                --timeout;
        } /* while */

        return sscape_read_unsafe(io_base, reg) & 0x01;
}

/*
 * Wait for the On-Board Processor to return its start-up
 * acknowledgement sequence. This wait is too long for
 * us to perform "busy-waiting", and so we must sleep.
 * This in turn means that we must not be holding any
 * spinlocks when we call this function.
 */
static int obp_startup_ack(struct soundscape *s, unsigned timeout)
{
        unsigned long end_time = jiffies + msecs_to_jiffies(timeout);

        do {
                unsigned long flags;
                int x;

                spin_lock_irqsave(&s->lock, flags);
                x = host_read_unsafe(s->io_base);
                spin_unlock_irqrestore(&s->lock, flags);
                if (x == 0xfe || x == 0xff)
                        return 1;

                msleep(10);
        } while (time_before(jiffies, end_time));

        return 0;
}

/*
 * Wait for the host to return its start-up acknowledgement
 * sequence. This wait is too long for us to perform
 * "busy-waiting", and so we must sleep. This in turn means
 * that we must not be holding any spinlocks when we call
 * this function.
 */
static int host_startup_ack(struct soundscape *s, unsigned timeout)
{
        unsigned long end_time = jiffies + msecs_to_jiffies(timeout);

        do {
                unsigned long flags;
                int x;

                spin_lock_irqsave(&s->lock, flags);
                x = host_read_unsafe(s->io_base);
                spin_unlock_irqrestore(&s->lock, flags);
                if (x == 0xfe)
                        return 1;

                msleep(10);
        } while (time_before(jiffies, end_time));

        return 0;
}

/*
 * Upload a byte-stream into the SoundScape using DMA channel A.
 */
static int upload_dma_data(struct soundscape *s, const unsigned char *data,
                           size_t size)
{
        unsigned long flags;
        struct snd_dma_buffer dma;
        int ret;
        unsigned char val;

        if (!get_dmabuf(s, &dma, PAGE_ALIGN(32 * 1024)))
                return -ENOMEM;

        spin_lock_irqsave(&s->lock, flags);

        /*
         * Reset the board ...
         */
        val = sscape_read_unsafe(s->io_base, GA_HMCTL_REG);
        sscape_write_unsafe(s->io_base, GA_HMCTL_REG, val & 0x3f);

        /*
         * Enable the DMA channels and configure them ...
         */
        val = (s->chip->dma1 << 4) | DMA_8BIT;
        sscape_write_unsafe(s->io_base, GA_DMAA_REG, val);
        sscape_write_unsafe(s->io_base, GA_DMAB_REG, 0x20);

        /*
         * Take the board out of reset ...
         */
        val = sscape_read_unsafe(s->io_base, GA_HMCTL_REG);
        sscape_write_unsafe(s->io_base, GA_HMCTL_REG, val | 0x80);

        /*
         * Upload the firmware to the SoundScape
         * board through the DMA channel ...
         */
        while (size != 0) {
                unsigned long len;

                len = min(size, dma.bytes);
                memcpy(dma.area, data, len);
                data += len;
                size -= len;

                snd_dma_program(s->chip->dma1, dma.addr, len, DMA_MODE_WRITE);
                sscape_start_dma_unsafe(s->io_base, GA_DMAA_REG);
                if (!sscape_wait_dma_unsafe(s->io_base, GA_DMAA_REG, 5000)) {
                        /*
                         * Don't forget to release this spinlock we're holding
                         */
                        spin_unlock_irqrestore(&s->lock, flags);

                        snd_printk(KERN_ERR
                                        "sscape: DMA upload has timed out\n");
                        ret = -EAGAIN;
                        goto _release_dma;
                }
        } /* while */

        set_host_mode_unsafe(s->io_base);
        outb(0x0, s->io_base);

        /*
         * Boot the board ... (I think)
         */
        val = sscape_read_unsafe(s->io_base, GA_HMCTL_REG);
        sscape_write_unsafe(s->io_base, GA_HMCTL_REG, val | 0x40);
        spin_unlock_irqrestore(&s->lock, flags);

        /*
         * If all has gone well, then the board should acknowledge
         * the new upload and tell us that it has rebooted OK. We
         * give it 5 seconds (max) ...
         */
        ret = 0;
        if (!obp_startup_ack(s, 5000)) {
                snd_printk(KERN_ERR "sscape: No response "
                                    "from on-board processor after upload\n");
                ret = -EAGAIN;
        } else if (!host_startup_ack(s, 5000)) {
                snd_printk(KERN_ERR
                                "sscape: SoundScape failed to initialise\n");
                ret = -EAGAIN;
        }

_release_dma:
        /*
         * NOTE!!! We are NOT holding any spinlocks at this point !!!
         */
        sscape_write(s, GA_DMAA_REG, (s->ic_type == IC_OPUS ? 0x40 : 0x70));
        free_dmabuf(&dma);

        return ret;
}

/*
 * Upload the bootblock(?) into the SoundScape. The only
 * purpose of this block of code seems to be to tell
 * us which version of the microcode we should be using.
 */
static int sscape_upload_bootblock(struct snd_card *card)
{
        struct soundscape *sscape = get_card_soundscape(card);
        unsigned long flags;
        const struct firmware *init_fw = NULL;
        int data = 0;
        int ret;

        ret = request_firmware(&init_fw, "scope.cod", card->dev);
        if (ret < 0) {
                snd_printk(KERN_ERR "sscape: Error loading scope.cod");
                return ret;
        }
        ret = upload_dma_data(sscape, init_fw->data, init_fw->size);

        release_firmware(init_fw);

        spin_lock_irqsave(&sscape->lock, flags);
        if (ret == 0)
                data = host_read_ctrl_unsafe(sscape->io_base, 100);

        if (data & 0x10)
                sscape_write_unsafe(sscape->io_base, GA_SMCFGA_REG, 0x2f);

        spin_unlock_irqrestore(&sscape->lock, flags);

        data &= 0xf;
        if (ret == 0 && data > 7) {
                snd_printk(KERN_ERR
                                "sscape: timeout reading firmware version\n");
                ret = -EAGAIN;
        }

        return (ret == 0) ? data : ret;
}

/*
 * Upload the microcode into the SoundScape.
 */
static int sscape_upload_microcode(struct snd_card *card, int version)
{
        struct soundscape *sscape = get_card_soundscape(card);
        const struct firmware *init_fw = NULL;
        char name[14];
        int err;

        snprintf(name, sizeof(name), "sndscape.co%d", version);

        err = request_firmware(&init_fw, name, card->dev);
        if (err < 0) {
                snd_printk(KERN_ERR "sscape: Error loading sndscape.co%d",
                                version);
                return err;
        }
        err = upload_dma_data(sscape, init_fw->data, init_fw->size);
        if (err == 0)
                snd_printk(KERN_INFO "sscape: MIDI firmware loaded %zu KBs\n",
                                init_fw->size >> 10);

        release_firmware(init_fw);

        return err;
}

/*
 * Mixer control for the SoundScape's MIDI device.
 */
static int sscape_midi_info(struct snd_kcontrol *ctl,
                            struct snd_ctl_elem_info *uinfo)
{
        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
        uinfo->count = 1;
        uinfo->value.integer.min = 0;
        uinfo->value.integer.max = 127;
        return 0;
}

static int sscape_midi_get(struct snd_kcontrol *kctl,
                           struct snd_ctl_elem_value *uctl)
{
        struct snd_wss *chip = snd_kcontrol_chip(kctl);
        struct snd_card *card = chip->card;
        register struct soundscape *s = get_card_soundscape(card);
        unsigned long flags;

        spin_lock_irqsave(&s->lock, flags);
        uctl->value.integer.value[0] = s->midi_vol;
        spin_unlock_irqrestore(&s->lock, flags);
        return 0;
}

static int sscape_midi_put(struct snd_kcontrol *kctl,
                           struct snd_ctl_elem_value *uctl)
{
        struct snd_wss *chip = snd_kcontrol_chip(kctl);
        struct snd_card *card = chip->card;
        struct soundscape *s = get_card_soundscape(card);
        unsigned long flags;
        int change;
        unsigned char new_val;

        spin_lock_irqsave(&s->lock, flags);

        new_val = uctl->value.integer.value[0] & 127;
        /*
         * We need to put the board into HOST mode before we
         * can send any volume-changing HOST commands ...
         */
        set_host_mode_unsafe(s->io_base);

        /*
         * To successfully change the MIDI volume setting, you seem to
         * have to write a volume command, write the new volume value,
         * and then perform another volume-related command. Perhaps the
         * first command is an "open" and the second command is a "close"?
         */
        if (s->midi_vol == new_val) {
                change = 0;
                goto __skip_change;
        }
        change = host_write_ctrl_unsafe(s->io_base, CMD_SET_MIDI_VOL, 100)
                 && host_write_ctrl_unsafe(s->io_base, new_val, 100)
                 && host_write_ctrl_unsafe(s->io_base, CMD_XXX_MIDI_VOL, 100)
                 && host_write_ctrl_unsafe(s->io_base, new_val, 100);
        s->midi_vol = new_val;
__skip_change:

        /*
         * Take the board out of HOST mode and back into MIDI mode ...
         */
        set_midi_mode_unsafe(s->io_base);

        spin_unlock_irqrestore(&s->lock, flags);
        return change;
}

static const struct snd_kcontrol_new midi_mixer_ctl = {
        .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
        .name = "MIDI",
        .info = sscape_midi_info,
        .get = sscape_midi_get,
        .put = sscape_midi_put
};

/*
 * The SoundScape can use two IRQs from a possible set of four.
 * These IRQs are encoded as bit patterns so that they can be
 * written to the control registers.
 */
static unsigned get_irq_config(int sscape_type, int irq)
{
        static const int valid_irq[] = { 9, 5, 7, 10 };
        static const int old_irq[] = { 9, 7, 5, 15 };
        unsigned cfg;

        if (sscape_type == MEDIA_FX) {
                for (cfg = 0; cfg < ARRAY_SIZE(old_irq); ++cfg)
                        if (irq == old_irq[cfg])
                                return cfg;
        } else {
                for (cfg = 0; cfg < ARRAY_SIZE(valid_irq); ++cfg)
                        if (irq == valid_irq[cfg])
                                return cfg;
        }

        return INVALID_IRQ;
}

/*
 * Perform certain arcane port-checks to see whether there
 * is a SoundScape board lurking behind the given ports.
 */
static int detect_sscape(struct soundscape *s, long wss_io)
{
        unsigned long flags;
        unsigned d;
        int retval = 0;

        spin_lock_irqsave(&s->lock, flags);

        /*
         * The following code is lifted from the original OSS driver,
         * and as I don't have a datasheet I cannot really comment
         * on what it is doing...
         */
        if ((inb(HOST_CTRL_IO(s->io_base)) & 0x78) != 0)
                goto _done;

        d = inb(ODIE_ADDR_IO(s->io_base)) & 0xf0;
        if ((d & 0x80) != 0)
                goto _done;

        if (d == 0)
                s->ic_type = IC_ODIE;
        else if ((d & 0x60) != 0)
                s->ic_type = IC_OPUS;
        else
                goto _done;

        outb(0xfa, ODIE_ADDR_IO(s->io_base));
        if ((inb(ODIE_ADDR_IO(s->io_base)) & 0x9f) != 0x0a)
                goto _done;

        outb(0xfe, ODIE_ADDR_IO(s->io_base));
        if ((inb(ODIE_ADDR_IO(s->io_base)) & 0x9f) != 0x0e)
                goto _done;

        outb(0xfe, ODIE_ADDR_IO(s->io_base));
        d = inb(ODIE_DATA_IO(s->io_base));
        if (s->type != SSCAPE_VIVO && (d & 0x9f) != 0x0e)
                goto _done;

        if (s->ic_type == IC_OPUS)
                activate_ad1845_unsafe(s->io_base);

        if (s->type == SSCAPE_VIVO)
                wss_io += 4;

        d  = sscape_read_unsafe(s->io_base, GA_HMCTL_REG);
        sscape_write_unsafe(s->io_base, GA_HMCTL_REG, d | 0xc0);

        /* wait for WSS codec */
        for (d = 0; d < 500; d++) {
                if ((inb(wss_io) & 0x80) == 0)
                        break;
                spin_unlock_irqrestore(&s->lock, flags);
                msleep(1);
                spin_lock_irqsave(&s->lock, flags);
        }

        if ((inb(wss_io) & 0x80) != 0)
                goto _done;

        if (inb(wss_io + 2) == 0xff)
                goto _done;

        d  = sscape_read_unsafe(s->io_base, GA_HMCTL_REG) & 0x3f;
        sscape_write_unsafe(s->io_base, GA_HMCTL_REG, d);

        if ((inb(wss_io) & 0x80) != 0)
                s->type = MEDIA_FX;

        d = sscape_read_unsafe(s->io_base, GA_HMCTL_REG);
        sscape_write_unsafe(s->io_base, GA_HMCTL_REG, d | 0xc0);
        /* wait for WSS codec */
        for (d = 0; d < 500; d++) {
                if ((inb(wss_io) & 0x80) == 0)
                        break;
                spin_unlock_irqrestore(&s->lock, flags);
                msleep(1);
                spin_lock_irqsave(&s->lock, flags);
        }

        /*
         * SoundScape successfully detected!
         */
        retval = 1;

_done:
        spin_unlock_irqrestore(&s->lock, flags);
        return retval;
}

/*
 * ALSA callback function, called when attempting to open the MIDI device.
 * Check that the MIDI firmware has been loaded, because we don't want
 * to crash the machine. Also check that someone isn't using the hardware
 * IOCTL device.
 */
static int mpu401_open(struct snd_mpu401 *mpu)
{
        if (!verify_mpu401(mpu)) {
                snd_printk(KERN_ERR "sscape: MIDI disabled, "
                                    "please load firmware\n");
                return -ENODEV;
        }

        return 0;
}

/*
 * Initialise an MPU-401 subdevice for MIDI support on the SoundScape.
 */
static int create_mpu401(struct snd_card *card, int devnum,
                         unsigned long port, int irq)
{
        struct soundscape *sscape = get_card_soundscape(card);
        struct snd_rawmidi *rawmidi;
        int err;

        err = snd_mpu401_uart_new(card, devnum, MPU401_HW_MPU401, port,
                                  MPU401_INFO_INTEGRATED, irq, &rawmidi);
        if (err == 0) {
                struct snd_mpu401 *mpu = rawmidi->private_data;
                mpu->open_input = mpu401_open;
                mpu->open_output = mpu401_open;
                mpu->private_data = sscape;

                initialise_mpu401(mpu);
        }

        return err;
}


/*
 * Create an AD1845 PCM subdevice on the SoundScape. The AD1845
 * is very much like a CS4231, with a few extra bits. We will
 * try to support at least some of the extra bits by overriding
 * some of the CS4231 callback.
 */
static int create_ad1845(struct snd_card *card, unsigned port,
                         int irq, int dma1, int dma2)
{
        register struct soundscape *sscape = get_card_soundscape(card);
        struct snd_wss *chip;
        int err;
        int codec_type = WSS_HW_DETECT;

        switch (sscape->type) {
        case MEDIA_FX:
        case SSCAPE:
                /*
                 * There are some freak examples of early Soundscape cards
                 * with CS4231 instead of AD1848/CS4248. Unfortunately, the
                 * CS4231 works only in CS4248 compatibility mode on
                 * these cards so force it.
                 */
                if (sscape->ic_type != IC_OPUS)
                        codec_type = WSS_HW_AD1848;
                break;

        case SSCAPE_VIVO:
                port += 4;
                break;
        default:
                break;
        }

        err = snd_wss_create(card, port, -1, irq, dma1, dma2,
                             codec_type, WSS_HWSHARE_DMA1, &chip);
        if (!err) {
                unsigned long flags;

                if (sscape->type != SSCAPE_VIVO) {
                        /*
                         * The input clock frequency on the SoundScape must
                         * be 14.31818 MHz, because we must set this register
                         * to get the playback to sound correct ...
                         */
                        snd_wss_mce_up(chip);
                        spin_lock_irqsave(&chip->reg_lock, flags);
                        snd_wss_out(chip, AD1845_CLOCK, 0x20);
                        spin_unlock_irqrestore(&chip->reg_lock, flags);
                        snd_wss_mce_down(chip);

                }

                err = snd_wss_pcm(chip, 0);
                if (err < 0) {
                        snd_printk(KERN_ERR "sscape: No PCM device "
                                            "for AD1845 chip\n");
                        goto _error;
                }

                err = snd_wss_mixer(chip);
                if (err < 0) {
                        snd_printk(KERN_ERR "sscape: No mixer device "
                                            "for AD1845 chip\n");
                        goto _error;
                }
                if (chip->hardware != WSS_HW_AD1848) {
                        err = snd_wss_timer(chip, 0);
                        if (err < 0) {
                                snd_printk(KERN_ERR "sscape: No timer device "
                                                    "for AD1845 chip\n");
                                goto _error;
                        }
                }

                if (sscape->type != SSCAPE_VIVO) {
                        err = snd_ctl_add(card,
                                          snd_ctl_new1(&midi_mixer_ctl, chip));
                        if (err < 0) {
                                snd_printk(KERN_ERR "sscape: Could not create "
                                                    "MIDI mixer control\n");
                                goto _error;
                        }
                }

                sscape->chip = chip;
        }

_error:
        return err;
}


/*
 * Create an ALSA soundcard entry for the SoundScape, using
 * the given list of port, IRQ and DMA resources.
 */
static int create_sscape(int dev, struct snd_card *card)
{
        struct soundscape *sscape = get_card_soundscape(card);
        unsigned dma_cfg;
        unsigned irq_cfg;
        unsigned mpu_irq_cfg;
        struct resource *io_res;
        struct resource *wss_res;
        unsigned long flags;
        int err;
        int val;
        const char *name;

        /*
         * Grab IO ports that we will need to probe so that we
         * can detect and control this hardware ...
         */
        io_res = request_region(port[dev], 8, "SoundScape");
        if (!io_res) {
                snd_printk(KERN_ERR
                           "sscape: can't grab port 0x%lx\n", port[dev]);
                return -EBUSY;
        }
        wss_res = NULL;
        if (sscape->type == SSCAPE_VIVO) {
                wss_res = request_region(wss_port[dev], 4, "SoundScape");
                if (!wss_res) {
                        snd_printk(KERN_ERR "sscape: can't grab port 0x%lx\n",
                                            wss_port[dev]);
                        err = -EBUSY;
                        goto _release_region;
                }
        }

        /*
         * Grab one DMA channel ...
         */
        err = request_dma(dma[dev], "SoundScape");
        if (err < 0) {
                snd_printk(KERN_ERR "sscape: can't grab DMA %d\n", dma[dev]);
                goto _release_region;
        }

        spin_lock_init(&sscape->lock);
        sscape->io_res = io_res;
        sscape->wss_res = wss_res;
        sscape->io_base = port[dev];

        if (!detect_sscape(sscape, wss_port[dev])) {
                printk(KERN_ERR "sscape: hardware not detected at 0x%x\n",
                        sscape->io_base);
                err = -ENODEV;
                goto _release_dma;
        }

        switch (sscape->type) {
        case MEDIA_FX:
                name = "MediaFX/SoundFX";
                break;
        case SSCAPE:
                name = "Soundscape";
                break;
        case SSCAPE_PNP:
                name = "Soundscape PnP";
                break;
        case SSCAPE_VIVO:
                name = "Soundscape VIVO";
                break;
        default:
                name = "unknown Soundscape";
                break;
        }

        printk(KERN_INFO "sscape: %s card detected at 0x%x, using IRQ %d, DMA %d\n",

                         name, sscape->io_base, irq[dev], dma[dev]);

        /*
         * Check that the user didn't pass us garbage data ...
         */
        irq_cfg = get_irq_config(sscape->type, irq[dev]);
        if (irq_cfg == INVALID_IRQ) {
                snd_printk(KERN_ERR "sscape: Invalid IRQ %d\n", irq[dev]);
                err = -ENXIO;
                goto _release_dma;
        }

        mpu_irq_cfg = get_irq_config(sscape->type, mpu_irq[dev]);
        if (mpu_irq_cfg == INVALID_IRQ) {
                snd_printk(KERN_ERR "sscape: Invalid IRQ %d\n", mpu_irq[dev]);
                err = -ENXIO;
                goto _release_dma;
        }

        /*
         * Tell the on-board devices where their resources are (I think -
         * I can't be sure without a datasheet ... So many magic values!)
         */
        spin_lock_irqsave(&sscape->lock, flags);

        sscape_write_unsafe(sscape->io_base, GA_SMCFGA_REG, 0x2e);
        sscape_write_unsafe(sscape->io_base, GA_SMCFGB_REG, 0x00);

        /*
         * Enable and configure the DMA channels ...
         */
        sscape_write_unsafe(sscape->io_base, GA_DMACFG_REG, 0x50);
        dma_cfg = (sscape->ic_type == IC_OPUS ? 0x40 : 0x70);
        sscape_write_unsafe(sscape->io_base, GA_DMAA_REG, dma_cfg);
        sscape_write_unsafe(sscape->io_base, GA_DMAB_REG, 0x20);

        mpu_irq_cfg |= mpu_irq_cfg << 2;
        val = sscape_read_unsafe(sscape->io_base, GA_HMCTL_REG) & 0xF7;
        if (joystick[dev])
                val |= 8;
        sscape_write_unsafe(sscape->io_base, GA_HMCTL_REG, val | 0x10);
        sscape_write_unsafe(sscape->io_base, GA_INTCFG_REG, 0xf0 | mpu_irq_cfg);
        sscape_write_unsafe(sscape->io_base,
                            GA_CDCFG_REG, 0x09 | DMA_8BIT
                            | (dma[dev] << 4) | (irq_cfg << 1));
        /*
         * Enable the master IRQ ...
         */
        sscape_write_unsafe(sscape->io_base, GA_INTENA_REG, 0x80);

        spin_unlock_irqrestore(&sscape->lock, flags);

        /*
         * We have now enabled the codec chip, and so we should
         * detect the AD1845 device ...
         */
        err = create_ad1845(card, wss_port[dev], irq[dev],
                            dma[dev], dma2[dev]);
        if (err < 0) {
                snd_printk(KERN_ERR
                                "sscape: No AD1845 device at 0x%lx, IRQ %d\n",
                                wss_port[dev], irq[dev]);
                goto _release_dma;
        }
        strcpy(card->driver, "SoundScape");
        strcpy(card->shortname, name);
        snprintf(card->longname, sizeof(card->longname),
                 "%s at 0x%lx, IRQ %d, DMA1 %d, DMA2 %d\n",
                 name, sscape->chip->port, sscape->chip->irq,
                 sscape->chip->dma1, sscape->chip->dma2);

#define MIDI_DEVNUM  0
        if (sscape->type != SSCAPE_VIVO) {
                err = sscape_upload_bootblock(card);
                if (err >= 0)
                        err = sscape_upload_microcode(card, err);

                if (err == 0) {
                        err = create_mpu401(card, MIDI_DEVNUM, port[dev],
                                            mpu_irq[dev]);
                        if (err < 0) {
                                snd_printk(KERN_ERR "sscape: Failed to create "
                                                "MPU-401 device at 0x%lx\n",
                                                port[dev]);
                                goto _release_dma;
                        }

                        /*
                         * Initialize mixer
                         */
                        spin_lock_irqsave(&sscape->lock, flags);
                        sscape->midi_vol = 0;
                        host_write_ctrl_unsafe(sscape->io_base,
                                                CMD_SET_MIDI_VOL, 100);
                        host_write_ctrl_unsafe(sscape->io_base,
                                                sscape->midi_vol, 100);
                        host_write_ctrl_unsafe(sscape->io_base,
                                                CMD_XXX_MIDI_VOL, 100);
                        host_write_ctrl_unsafe(sscape->io_base,
                                                sscape->midi_vol, 100);
                        host_write_ctrl_unsafe(sscape->io_base,
                                                CMD_SET_EXTMIDI, 100);
                        host_write_ctrl_unsafe(sscape->io_base,
                                                0, 100);
                        host_write_ctrl_unsafe(sscape->io_base, CMD_ACK, 100);

                        set_midi_mode_unsafe(sscape->io_base);
                        spin_unlock_irqrestore(&sscape->lock, flags);
                }
        }

        /*
         * Now that we have successfully created this sound card,
         * it is safe to store the pointer.
         * NOTE: we only register the sound card's "destructor"
         *       function now that our "constructor" has completed.
         */
        card->private_free = soundscape_free;

        return 0;

_release_dma:
        free_dma(dma[dev]);

_release_region:
        release_and_free_resource(wss_res);
        release_and_free_resource(io_res);

        return err;
}


static int snd_sscape_match(struct device *pdev, unsigned int i)
{
        /*
         * Make sure we were given ALL of the other parameters.
         */
        if (port[i] == SNDRV_AUTO_PORT)
                return 0;

        if (irq[i] == SNDRV_AUTO_IRQ ||
            mpu_irq[i] == SNDRV_AUTO_IRQ ||
            dma[i] == SNDRV_AUTO_DMA) {
                printk(KERN_INFO
                       "sscape: insufficient parameters, "
                       "need IO, IRQ, MPU-IRQ and DMA\n");
                return 0;
        }

        return 1;
}

static int snd_sscape_probe(struct device *pdev, unsigned int dev)
{
        struct snd_card *card;
        struct soundscape *sscape;
        int ret;

        ret = snd_card_new(pdev, index[dev], id[dev], THIS_MODULE,
                           sizeof(struct soundscape), &card);
        if (ret < 0)
                return ret;

        sscape = get_card_soundscape(card);
        sscape->type = SSCAPE;

        dma[dev] &= 0x03;

        ret = create_sscape(dev, card);
        if (ret < 0)
                goto _release_card;

        ret = snd_card_register(card);
        if (ret < 0) {
                snd_printk(KERN_ERR "sscape: Failed to register sound card\n");
                goto _release_card;
        }
        dev_set_drvdata(pdev, card);
        return 0;

_release_card:
        snd_card_free(card);
        return ret;
}

static void snd_sscape_remove(struct device *devptr, unsigned int dev)
{
        snd_card_free(dev_get_drvdata(devptr));
}

#define DEV_NAME "sscape"

static struct isa_driver snd_sscape_driver = {
        .match          = snd_sscape_match,
        .probe          = snd_sscape_probe,
        .remove         = snd_sscape_remove,
        /* FIXME: suspend/resume */
        .driver         = {
                .name   = DEV_NAME
        },
};

#ifdef CONFIG_PNP
static inline int get_next_autoindex(int i)
{
        while (i < SNDRV_CARDS && port[i] != SNDRV_AUTO_PORT)
                ++i;
        return i;
}


static int sscape_pnp_detect(struct pnp_card_link *pcard,
                             const struct pnp_card_device_id *pid)
{
        static int idx = 0;
        struct pnp_dev *dev;
        struct snd_card *card;
        struct soundscape *sscape;
        int ret;

        /*
         * Allow this function to fail *quietly* if all the ISA PnP
         * devices were configured using module parameters instead.
         */
        idx = get_next_autoindex(idx);
        if (idx >= SNDRV_CARDS)
                return -ENOSPC;

        /*
         * Check that we still have room for another sound card ...
         */
        dev = pnp_request_card_device(pcard, pid->devs[0].id, NULL);
        if (!dev)
                return -ENODEV;

        if (!pnp_is_active(dev)) {
                if (pnp_activate_dev(dev) < 0) {
                        snd_printk(KERN_INFO "sscape: device is inactive\n");
                        return -EBUSY;
                }
        }

        /*
         * Create a new ALSA sound card entry, in anticipation
         * of detecting our hardware ...
         */
        ret = snd_card_new(&pcard->card->dev,
                           index[idx], id[idx], THIS_MODULE,
                           sizeof(struct soundscape), &card);
        if (ret < 0)
                return ret;

        sscape = get_card_soundscape(card);

        /*
         * Identify card model ...
         */
        if (!strncmp("ENS4081", pid->id, 7))
                sscape->type = SSCAPE_VIVO;
        else
                sscape->type = SSCAPE_PNP;

        /*
         * Read the correct parameters off the ISA PnP bus ...
         */
        port[idx] = pnp_port_start(dev, 0);
        irq[idx] = pnp_irq(dev, 0);
        mpu_irq[idx] = pnp_irq(dev, 1);
        dma[idx] = pnp_dma(dev, 0) & 0x03;
        if (sscape->type == SSCAPE_PNP) {
                dma2[idx] = dma[idx];
                wss_port[idx] = CODEC_IO(port[idx]);
        } else {
                wss_port[idx] = pnp_port_start(dev, 1);
                dma2[idx] = pnp_dma(dev, 1);
        }

        ret = create_sscape(idx, card);
        if (ret < 0)
                goto _release_card;

        ret = snd_card_register(card);
        if (ret < 0) {
                snd_printk(KERN_ERR "sscape: Failed to register sound card\n");
                goto _release_card;
        }

        pnp_set_card_drvdata(pcard, card);
        ++idx;
        return 0;

_release_card:
        snd_card_free(card);
        return ret;
}

static void sscape_pnp_remove(struct pnp_card_link *pcard)
{
        snd_card_free(pnp_get_card_drvdata(pcard));
        pnp_set_card_drvdata(pcard, NULL);
}

static struct pnp_card_driver sscape_pnpc_driver = {
        .flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
        .name = "sscape",
        .id_table = sscape_pnpids,
        .probe = sscape_pnp_detect,
        .remove = sscape_pnp_remove,
};

#endif /* CONFIG_PNP */

static int __init sscape_init(void)
{
        int err;

        err = isa_register_driver(&snd_sscape_driver, SNDRV_CARDS);
#ifdef CONFIG_PNP
        if (!err)
                isa_registered = 1;

        err = pnp_register_card_driver(&sscape_pnpc_driver);
        if (!err)
                pnp_registered = 1;

        if (isa_registered)
                err = 0;
#endif
        return err;
}

static void __exit sscape_exit(void)
{
#ifdef CONFIG_PNP
        if (pnp_registered)
                pnp_unregister_card_driver(&sscape_pnpc_driver);
        if (isa_registered)
#endif
                isa_unregister_driver(&snd_sscape_driver);
}

module_init(sscape_init);
module_exit(sscape_exit);