/*
 *  linux/drivers/sound/vidc.c
 *
 *  Copyright (C) 1997-2000 by Russell King <rmk@arm.linux.org.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  VIDC20 audio driver.
 *
 * The VIDC20 sound hardware consists of the VIDC20 itself, a DAC and a DMA
 * engine.  The DMA transfers fixed-format (16-bit little-endian linear)
 * samples to the VIDC20, which then transfers this data serially to the
 * DACs.  The samplerate is controlled by the VIDC.
 *
 * We currently support a mixer device, but it is currently non-functional.
 */

#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>

#include <mach/hardware.h>
#include <asm/dma.h>
#include <asm/io.h>
#include <asm/hardware/iomd.h>
#include <asm/irq.h>

#include "sound_config.h"
#include "vidc.h"

#ifndef _SIOC_TYPE
#define _SIOC_TYPE(x)   _IOC_TYPE(x)
#endif
#ifndef _SIOC_NR
#define _SIOC_NR(x)     _IOC_NR(x)
#endif

#define VIDC_SOUND_CLOCK        (250000)
#define VIDC_SOUND_CLOCK_EXT    (176400)

/*
 * When using SERIAL SOUND mode (external DAC), the number of physical
 * channels is fixed at 2.
 */
static int              vidc_busy;
static int              vidc_adev;
static int              vidc_audio_rate;
static char             vidc_audio_format;
static char             vidc_audio_channels;

static unsigned char    vidc_level_l[SOUND_MIXER_NRDEVICES] = {
        85,             /* master       */
        50,             /* bass         */
        50,             /* treble       */
        0,              /* synth        */
        75,             /* pcm          */
        0,              /* speaker      */
        100,            /* ext line     */
        0,              /* mic          */
        100,            /* CD           */
        0,
};

static unsigned char    vidc_level_r[SOUND_MIXER_NRDEVICES] = {
        85,             /* master       */
        50,             /* bass         */
        50,             /* treble       */
        0,              /* synth        */
        75,             /* pcm          */
        0,              /* speaker      */
        100,            /* ext line     */
        0,              /* mic          */
        100,            /* CD           */
        0,
};

static unsigned int     vidc_audio_volume_l;    /* left PCM vol, 0 - 65536 */
static unsigned int     vidc_audio_volume_r;    /* right PCM vol, 0 - 65536 */

extern void     vidc_update_filler(int bits, int channels);
extern int      softoss_dev;

static void
vidc_mixer_set(int mdev, unsigned int level)
{
        unsigned int lev_l = level & 0x007f;
        unsigned int lev_r = (level & 0x7f00) >> 8;
        unsigned int mlev_l, mlev_r;

        if (lev_l > 100)
                lev_l = 100;
        if (lev_r > 100)
                lev_r = 100;

#define SCALE(lev,master)       ((lev) * (master) * 65536 / 10000)

        mlev_l = vidc_level_l[SOUND_MIXER_VOLUME];
        mlev_r = vidc_level_r[SOUND_MIXER_VOLUME];

        switch (mdev) {
        case SOUND_MIXER_VOLUME:
        case SOUND_MIXER_PCM:
                vidc_level_l[mdev] = lev_l;
                vidc_level_r[mdev] = lev_r;

                vidc_audio_volume_l = SCALE(lev_l, mlev_l);
                vidc_audio_volume_r = SCALE(lev_r, mlev_r);
/*printk("VIDC: PCM vol %05X %05X\n", vidc_audio_volume_l, vidc_audio_volume_r);*/
                break;
        }
#undef SCALE
}

static int vidc_mixer_ioctl(int dev, unsigned int cmd, void __user *arg)
{
        unsigned int val;
        unsigned int mdev;

        if (_SIOC_TYPE(cmd) != 'M')
                return -EINVAL;

        mdev = _SIOC_NR(cmd);

        if (_SIOC_DIR(cmd) & _SIOC_WRITE) {
                if (get_user(val, (unsigned int __user *)arg))
                        return -EFAULT;

                if (mdev < SOUND_MIXER_NRDEVICES)
                        vidc_mixer_set(mdev, val);
                else
                        return -EINVAL;
        }

        /*
         * Return parameters
         */
        switch (mdev) {
        case SOUND_MIXER_RECSRC:
                val = 0;
                break;

        case SOUND_MIXER_DEVMASK:
                val = SOUND_MASK_VOLUME | SOUND_MASK_PCM | SOUND_MASK_SYNTH;
                break;

        case SOUND_MIXER_STEREODEVS:
                val = SOUND_MASK_VOLUME | SOUND_MASK_PCM | SOUND_MASK_SYNTH;
                break;

        case SOUND_MIXER_RECMASK:
                val = 0;
                break;

        case SOUND_MIXER_CAPS:
                val = 0;
                break;

        default:
                if (mdev < SOUND_MIXER_NRDEVICES)
                        val = vidc_level_l[mdev] | vidc_level_r[mdev] << 8;
                else
                        return -EINVAL;
        }

        return put_user(val, (unsigned int __user *)arg) ? -EFAULT : 0;
}

static unsigned int vidc_audio_set_format(int dev, unsigned int fmt)
{
        switch (fmt) {
        default:
                fmt = AFMT_S16_LE;
        case AFMT_U8:
        case AFMT_S8:
        case AFMT_S16_LE:
                vidc_audio_format = fmt;
                vidc_update_filler(vidc_audio_format, vidc_audio_channels);
        case AFMT_QUERY:
                break;
        }
        return vidc_audio_format;
}

#define my_abs(i) ((i)<0 ? -(i) : (i))

static int vidc_audio_set_speed(int dev, int rate)
{
        if (rate) {
                unsigned int hwctrl, hwrate, hwrate_ext, rate_int, rate_ext;
                unsigned int diff_int, diff_ext;
                unsigned int newsize, new2size;

                hwctrl = 0x00000003;

                /* Using internal clock */
                hwrate = (((VIDC_SOUND_CLOCK * 2) / rate) + 1) >> 1;
                if (hwrate < 3)
                        hwrate = 3;
                if (hwrate > 255)
                        hwrate = 255;

                /* Using exernal clock */
                hwrate_ext = (((VIDC_SOUND_CLOCK_EXT * 2) / rate) + 1) >> 1;
                if (hwrate_ext < 3)
                        hwrate_ext = 3;
                if (hwrate_ext > 255)
                        hwrate_ext = 255;

                rate_int = VIDC_SOUND_CLOCK / hwrate;
                rate_ext = VIDC_SOUND_CLOCK_EXT / hwrate_ext;

                /* Chose between external and internal clock */
                diff_int = my_abs(rate_ext-rate);
                diff_ext = my_abs(rate_int-rate);
                if (diff_ext < diff_int) {
                        /*printk("VIDC: external %d %d %d\n", rate, rate_ext, hwrate_ext);*/
                        hwrate=hwrate_ext;
                        hwctrl=0x00000002;
                        /* Allow roughly 0.4% tolerance */
                        if (diff_ext > (rate/256))
                                rate=rate_ext;
                } else {
                        /*printk("VIDC: internal %d %d %d\n", rate, rate_int, hwrate);*/
                        hwctrl=0x00000003;
                        /* Allow roughly 0.4% tolerance */
                        if (diff_int > (rate/256))
                                rate=rate_int;
                }

                vidc_writel(0xb0000000 | (hwrate - 2));
                vidc_writel(0xb1000000 | hwctrl);

                newsize = (10000 / hwrate) & ~3;
                if (newsize < 208)
                        newsize = 208;
                if (newsize > 4096)
                        newsize = 4096;
                for (new2size = 128; new2size < newsize; new2size <<= 1);
                if (new2size - newsize > newsize - (new2size >> 1))
                        new2size >>= 1;
                if (new2size > 4096) {
                        printk(KERN_ERR "VIDC: error: dma buffer (%d) %d > 4K\n",
                                newsize, new2size);
                        new2size = 4096;
                }
                /*printk("VIDC: dma size %d\n", new2size);*/
                dma_bufsize = new2size;
                vidc_audio_rate = rate;
        }
        return vidc_audio_rate;
}

static short vidc_audio_set_channels(int dev, short channels)
{
        switch (channels) {
        default:
                channels = 2;
        case 1:
        case 2:
                vidc_audio_channels = channels;
                vidc_update_filler(vidc_audio_format, vidc_audio_channels);
        case 0:
                break;
        }
        return vidc_audio_channels;
}

/*
 * Open the device
 */
static int vidc_audio_open(int dev, int mode)
{
        /* This audio device does not have recording capability */
        if (mode == OPEN_READ)
                return -EPERM;

        if (vidc_busy)
                return -EBUSY;

        vidc_busy = 1;
        return 0;
}

/*
 * Close the device
 */
static void vidc_audio_close(int dev)
{
        vidc_busy = 0;
}

/*
 * Output a block via DMA to sound device.
 *
 * We just set the DMA start and count; the DMA interrupt routine
 * will take care of formatting the samples (via the appropriate
 * vidc_filler routine), and flag via vidc_audio_dma_interrupt when
 * more data is required.
 */
static void
vidc_audio_output_block(int dev, unsigned long buf, int total_count, int one)
{
        struct dma_buffparms *dmap = audio_devs[dev]->dmap_out;
        unsigned long flags;

        local_irq_save(flags);
        dma_start = buf - (unsigned long)dmap->raw_buf_phys + (unsigned long)dmap->raw_buf;
        dma_count = total_count;
        local_irq_restore(flags);
}

static void
vidc_audio_start_input(int dev, unsigned long buf, int count, int intrflag)
{
}

static int vidc_audio_prepare_for_input(int dev, int bsize, int bcount)
{
        return -EINVAL;
}

static irqreturn_t vidc_audio_dma_interrupt(void)
{
        DMAbuf_outputintr(vidc_adev, 1);
        return IRQ_HANDLED;
}

/*
 * Prepare for outputting samples.
 *
 * Each buffer that will be passed will be `bsize' bytes long,
 * with a total of `bcount' buffers.
 */
static int vidc_audio_prepare_for_output(int dev, int bsize, int bcount)
{
        struct audio_operations *adev = audio_devs[dev];

        dma_interrupt = NULL;
        adev->dmap_out->flags |= DMA_NODMA;

        return 0;
}

/*
 * Stop our current operation.
 */
static void vidc_audio_reset(int dev)
{
        dma_interrupt = NULL;
}

static int vidc_audio_local_qlen(int dev)
{
        return /*dma_count !=*/ 0;
}

static void vidc_audio_trigger(int dev, int enable_bits)
{
        struct audio_operations *adev = audio_devs[dev];

        if (enable_bits & PCM_ENABLE_OUTPUT) {
                if (!(adev->dmap_out->flags & DMA_ACTIVE)) {
                        unsigned long flags;

                        local_irq_save(flags);

                        /* prevent recusion */
                        adev->dmap_out->flags |= DMA_ACTIVE;

                        dma_interrupt = vidc_audio_dma_interrupt;
                        vidc_sound_dma_irq(0, NULL);
                        iomd_writeb(DMA_CR_E | 0x10, IOMD_SD0CR);

                        local_irq_restore(flags);
                }
        }
}

static struct audio_driver vidc_audio_driver =
{
        .owner                  = THIS_MODULE,
        .open                   = vidc_audio_open,
        .close                  = vidc_audio_close,
        .output_block           = vidc_audio_output_block,
        .start_input            = vidc_audio_start_input,
        .prepare_for_input      = vidc_audio_prepare_for_input,
        .prepare_for_output     = vidc_audio_prepare_for_output,
        .halt_io                = vidc_audio_reset,
        .local_qlen             = vidc_audio_local_qlen,
        .trigger                = vidc_audio_trigger,
        .set_speed              = vidc_audio_set_speed,
        .set_bits               = vidc_audio_set_format,
        .set_channels           = vidc_audio_set_channels
};

static struct mixer_operations vidc_mixer_operations = {
        .owner          = THIS_MODULE,
        .id             = "VIDC",
        .name           = "VIDCsound",
        .ioctl          = vidc_mixer_ioctl
};

void vidc_update_filler(int format, int channels)
{
#define TYPE(fmt,ch) (((fmt)<<2) | ((ch)&3))

        switch (TYPE(format, channels)) {
        default:
        case TYPE(AFMT_U8, 1):
                vidc_filler = vidc_fill_1x8_u;
                break;

        case TYPE(AFMT_U8, 2):
                vidc_filler = vidc_fill_2x8_u;
                break;

        case TYPE(AFMT_S8, 1):
                vidc_filler = vidc_fill_1x8_s;
                break;

        case TYPE(AFMT_S8, 2):
                vidc_filler = vidc_fill_2x8_s;
                break;

        case TYPE(AFMT_S16_LE, 1):
                vidc_filler = vidc_fill_1x16_s;
                break;

        case TYPE(AFMT_S16_LE, 2):
                vidc_filler = vidc_fill_2x16_s;
                break;
        }
}

static void __init attach_vidc(struct address_info *hw_config)
{
        char name[32];
        int i, adev;

        sprintf(name, "VIDC %d-bit sound", hw_config->card_subtype);
        conf_printf(name, hw_config);
        memset(dma_buf, 0, sizeof(dma_buf));

        adev = sound_install_audiodrv(AUDIO_DRIVER_VERSION, name,
                        &vidc_audio_driver, sizeof(vidc_audio_driver),
                        DMA_AUTOMODE, AFMT_U8 | AFMT_S8 | AFMT_S16_LE,
                        NULL, hw_config->dma, hw_config->dma2);

        if (adev < 0)
                goto audio_failed;

        /*
         * 1024 bytes => 64 buffers
         */
        audio_devs[adev]->min_fragment = 10;
        audio_devs[adev]->mixer_dev = num_mixers;

        audio_devs[adev]->mixer_dev =
                sound_install_mixer(MIXER_DRIVER_VERSION,
                                name, &vidc_mixer_operations,
                                sizeof(vidc_mixer_operations), NULL);

        if (audio_devs[adev]->mixer_dev < 0)
                goto mixer_failed;

        for (i = 0; i < 2; i++) {
                dma_buf[i] = get_zeroed_page(GFP_KERNEL);
                if (!dma_buf[i]) {
                        printk(KERN_ERR "%s: can't allocate required buffers\n",
                                name);
                        goto mem_failed;
                }
                dma_pbuf[i] = virt_to_phys((void *)dma_buf[i]);
        }

        if (sound_alloc_dma(hw_config->dma, hw_config->name)) {
                printk(KERN_ERR "%s: DMA %d is in  use\n", name, hw_config->dma);
                goto dma_failed;
        }

        if (request_irq(hw_config->irq, vidc_sound_dma_irq, 0,
                        hw_config->name, &dma_start)) {
                printk(KERN_ERR "%s: IRQ %d is in use\n", name, hw_config->irq);
                goto irq_failed;
        }
        vidc_adev = adev;
        vidc_mixer_set(SOUND_MIXER_VOLUME, (85 | 85 << 8));

        return;

irq_failed:
        sound_free_dma(hw_config->dma);
dma_failed:
mem_failed:
        for (i = 0; i < 2; i++)
                free_page(dma_buf[i]);
        sound_unload_mixerdev(audio_devs[adev]->mixer_dev);
mixer_failed:
        sound_unload_audiodev(adev);
audio_failed:
        return;
}

static int __init probe_vidc(struct address_info *hw_config)
{
        hw_config->irq          = IRQ_DMAS0;
        hw_config->dma          = DMA_VIRTUAL_SOUND;
        hw_config->dma2         = -1;
        hw_config->card_subtype = 16;
        hw_config->name         = "VIDC20";
        return 1;
}

static void __exit unload_vidc(struct address_info *hw_config)
{
        int i, adev = vidc_adev;

        vidc_adev = -1;

        free_irq(hw_config->irq, &dma_start);
        sound_free_dma(hw_config->dma);

        if (adev >= 0) {
                sound_unload_mixerdev(audio_devs[adev]->mixer_dev);
                sound_unload_audiodev(adev);
                for (i = 0; i < 2; i++)
                        free_page(dma_buf[i]);
        }
}

static struct address_info cfg;

static int __init init_vidc(void)
{
        if (probe_vidc(&cfg) == 0)
                return -ENODEV;

        attach_vidc(&cfg);

        return 0;
}

static void __exit cleanup_vidc(void)
{
        unload_vidc(&cfg);
}

module_init(init_vidc);
module_exit(cleanup_vidc);

MODULE_AUTHOR("Russell King");
MODULE_DESCRIPTION("VIDC20 audio driver");
MODULE_LICENSE("GPL");