// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * cs5530.c - Initialisation code for Cyrix/NatSemi VSA1 softaudio
 *
 *      (C) Copyright 2007 Ash Willis <ashwillis@programmer.net>
 *      (C) Copyright 2003 Red Hat Inc <alan@lxorguk.ukuu.org.uk>
 *
 * This driver was ported (shamelessly ripped ;) from oss/kahlua.c but I did
 * mess with it a bit. The chip seems to have to have trouble with full duplex
 * mode. If we're recording in 8bit 8000kHz, say, and we then attempt to
 * simultaneously play back audio at 16bit 44100kHz, the device actually plays
 * back in the same format in which it is capturing. By forcing the chip to
 * always play/capture in 16/44100, we can let alsa-lib convert the samples and
 * that way we can hack up some full duplex audio. 
 * 
 * XpressAudio(tm) is used on the Cyrix MediaGX (now NatSemi Geode) systems.
 * The older version (VSA1) provides fairly good soundblaster emulation
 * although there are a couple of bugs: large DMA buffers break record,
 * and the MPU event handling seems suspect. VSA2 allows the native driver
 * to control the AC97 audio engine directly and requires a different driver.
 *
 * Thanks to National Semiconductor for providing the needed information
 * on the XpressAudio(tm) internals.
 *
 * TO DO:
 *      Investigate whether we can portably support Cognac (5520) in the
 *      same manner.
 */

#include <linux/delay.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <sound/core.h>
#include <sound/sb.h>
#include <sound/initval.h>

MODULE_AUTHOR("Ash Willis");
MODULE_DESCRIPTION("CS5530 Audio");
MODULE_LICENSE("GPL");

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;
static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for CS5530 Audio driver.");
module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for CS5530 Audio driver.");
module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable CS5530 Audio driver.");

struct snd_cs5530 {
        struct snd_card *card;
        struct pci_dev *pci;
        struct snd_sb *sb;
        unsigned long pci_base;
};

static const struct pci_device_id snd_cs5530_ids[] = {
        {PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_AUDIO, PCI_ANY_ID,
                                                        PCI_ANY_ID, 0, 0},
        {0,}
};

MODULE_DEVICE_TABLE(pci, snd_cs5530_ids);

static u8 snd_cs5530_mixer_read(unsigned long io, u8 reg)
{
        outb(reg, io + 4);
        udelay(20);
        reg = inb(io + 5);
        udelay(20);
        return reg;
}

static int snd_cs5530_create(struct snd_card *card,
                             struct pci_dev *pci)
{
        struct snd_cs5530 *chip = card->private_data;
        unsigned long sb_base;
        u8 irq, dma8, dma16 = 0;
        u16 map;
        void __iomem *mem;
        int err;

        err = pcim_enable_device(pci);
        if (err < 0)
                return err;

        chip->card = card;
        chip->pci = pci;

        mem = pcim_iomap_region(pci, 0, "CS5530");
        if (IS_ERR(mem))
                return PTR_ERR(mem);
        chip->pci_base = pci_resource_start(pci, 0);
        map = readw(mem + 0x18);

        /* Map bits
                0:1     * 0x20 + 0x200 = sb base
                2       sb enable
                3       adlib enable
                5       MPU enable 0x330
                6       MPU enable 0x300

           The other bits may be used internally so must be masked */

        sb_base = 0x220 + 0x20 * (map & 3);

        if (map & (1<<2))
                dev_info(card->dev, "XpressAudio at 0x%lx\n", sb_base);
        else {
                dev_err(card->dev, "Could not find XpressAudio!\n");
                return -ENODEV;
        }

        if (map & (1<<5))
                dev_info(card->dev, "MPU at 0x300\n");
        else if (map & (1<<6))
                dev_info(card->dev, "MPU at 0x330\n");

        irq = snd_cs5530_mixer_read(sb_base, 0x80) & 0x0F;
        dma8 = snd_cs5530_mixer_read(sb_base, 0x81);

        if (dma8 & 0x20)
                dma16 = 5;
        else if (dma8 & 0x40)
                dma16 = 6;
        else if (dma8 & 0x80)
                dma16 = 7;
        else {
                dev_err(card->dev, "No 16bit DMA enabled\n");
                return -ENODEV;
        }

        if (dma8 & 0x01)
                dma8 = 0;
        else if (dma8 & 02)
                dma8 = 1;
        else if (dma8 & 0x08)
                dma8 = 3;
        else {
                dev_err(card->dev, "No 8bit DMA enabled\n");
                return -ENODEV;
        }

        if (irq & 1)
                irq = 9;
        else if (irq & 2)
                irq = 5;
        else if (irq & 4)
                irq = 7;
        else if (irq & 8)
                irq = 10;
        else {
                dev_err(card->dev, "SoundBlaster IRQ not set\n");
                return -ENODEV;
        }

        dev_info(card->dev, "IRQ: %d DMA8: %d DMA16: %d\n", irq, dma8, dma16);

        err = snd_sbdsp_create(card, sb_base, irq, snd_sb16dsp_interrupt, dma8,
                                                dma16, SB_HW_CS5530, &chip->sb);
        if (err < 0) {
                dev_err(card->dev, "Could not create SoundBlaster\n");
                return err;
        }

        err = snd_sb16dsp_pcm(chip->sb, 0);
        if (err < 0) {
                dev_err(card->dev, "Could not create PCM\n");
                return err;
        }

        err = snd_sbmixer_new(chip->sb);
        if (err < 0) {
                dev_err(card->dev, "Could not create Mixer\n");
                return err;
        }

        return 0;
}

static int snd_cs5530_probe(struct pci_dev *pci,
                            const struct pci_device_id *pci_id)
{
        static int dev;
        struct snd_card *card;
        struct snd_cs5530 *chip;
        int err;

        if (dev >= SNDRV_CARDS)
                return -ENODEV;
        if (!enable[dev]) {
                dev++;
                return -ENOENT;
        }

        err = snd_devm_card_new(&pci->dev, index[dev], id[dev], THIS_MODULE,
                                sizeof(*chip), &card);
        if (err < 0)
                return err;
        chip = card->private_data;

        err = snd_cs5530_create(card, pci);
        if (err < 0)
                return err;

        strscpy(card->driver, "CS5530");
        strscpy(card->shortname, "CS5530 Audio");
        sprintf(card->longname, "%s at 0x%lx", card->shortname, chip->pci_base);

        err = snd_card_register(card);
        if (err < 0)
                return err;
        pci_set_drvdata(pci, card);
        dev++;
        return 0;
}

static struct pci_driver cs5530_driver = {
        .name = KBUILD_MODNAME,
        .id_table = snd_cs5530_ids,
        .probe = snd_cs5530_probe,
};

module_pci_driver(cs5530_driver);