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/*
 * drivers/sound/vidc_audio.c
 *
 * Audio routines for the VIDC
 *
 * Copyright (C) 1997 Russell King <rmk@arm.uk.linux.org>
 */

#include <asm/hardware.h>
#include <asm/io.h>
#include <asm/system.h>

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

/*
 * VIDC sound
 *
 * When using SERIAL SOUND mode (external DAC), the number of physical
 * channels is fixed at 2.  Therefore, the sample rate = vidc sample rate.
 */

static int      vidc_adev;

static int      vidc_audio_volume;
static int      vidc_audio_rate;
static char     vidc_audio_format;
static char     vidc_audio_channels;

extern void     vidc_update_filler(int bits, int channels);

int  vidc_audio_get_volume(void)
{
	return vidc_audio_volume;
}

int vidc_audio_set_volume(int newvol)
{
	vidc_audio_volume = newvol;
	return vidc_audio_volume;
}

static int vidc_audio_set_bits(int fmt)
{
printk("setting format: %d\n", fmt);
	switch (fmt)
	{
		case AFMT_QUERY:
			break;
		case AFMT_U8:
		case AFMT_S8:
		case AFMT_S16_LE:
			vidc_audio_format = fmt;
			vidc_update_filler(vidc_audio_format, vidc_audio_channels);
			break;
		default:
			vidc_audio_format = AFMT_S16_LE;
			vidc_update_filler(vidc_audio_format, vidc_audio_channels);
			break;
	}
	return vidc_audio_format;
}

static int vidc_audio_set_rate(int rate)
{
	if (rate)
	{
		int newsize, new2size;

		vidc_audio_rate = ((500000 / rate) + 1) >> 1;
		if (vidc_audio_rate < 3)
			vidc_audio_rate = 3;
		if (vidc_audio_rate > 255)
			vidc_audio_rate = 255;
		outl((vidc_audio_rate - 2) | 0xb0000000, IO_VIDC_BASE);
		outl(0xb1000003, IO_VIDC_BASE);
		newsize = (10000 / vidc_audio_rate) & ~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;
		dma_bufsize = new2size;
	}
	return 250000 / vidc_audio_rate;
}

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

/*
 * Open the device
 *
 * dev  - device
 * mode - mode to open device (logical OR of OPEN_READ and OPEN_WRITE)
 *
 * Called when opening the DMAbuf               (dmabuf.c:259)
 */
static int vidc_audio_open(int dev, int mode)
{
	if (vidc_busy)
		return -EBUSY;

	if ((mode & OPEN_READ) && (!mode & OPEN_WRITE))
	{
		/* This audio device doesn't have recording capability */
		return -EIO;
	}
	vidc_busy = 1;
	return 0;
}

/*
 * Close the device
 *
 * dev  - device
 *
 * Called when closing the DMAbuf               (dmabuf.c:477)
 *      after halt_xfer
 */
static void vidc_audio_close(int dev)
{
	vidc_busy = 0;
}

static int vidc_audio_ioctl(int dev, unsigned int cmd, caddr_t arg)
{
	int ret;

	switch (cmd)
	{
		case SOUND_PCM_WRITE_RATE:
			if (get_user(ret, (int *) arg))
				return -EFAULT;
			ret = vidc_audio_set_rate(ret);
			break;

		case SOUND_PCM_READ_RATE:
			ret = vidc_audio_set_rate(0);
			break;

		case SNDCTL_DSP_STEREO:
			if (get_user(ret, (int *) arg))
				return -EFAULT;
			ret = vidc_audio_set_channels(ret + 1) - 1;
			break;

		case SOUND_PCM_WRITE_CHANNELS:
			if (get_user(ret, (int *) arg))
				return -EFAULT;
			ret = vidc_audio_set_channels(ret);
			break;

		case SOUND_PCM_READ_CHANNELS:
			ret = vidc_audio_set_channels(0);
			break;

		case SNDCTL_DSP_SETFMT:
			if (get_user(ret, (int *) arg))
				return -EFAULT;
			ret = vidc_audio_set_bits(ret);
			break;

		case SOUND_PCM_READ_BITS:
			ret = vidc_audio_set_bits(0);
			break;

		case SOUND_PCM_WRITE_FILTER:
		case SOUND_PCM_READ_FILTER:
			return -EINVAL;

		default:
			return -EINVAL;
	}
	return put_user(ret, (int *) arg);
}

/*
 * Output a block via DMA to sound device
 *
 * dev          - device number
 * buf          - physical address of buffer
 * total_count  - total byte count in buffer
 * intrflag     - set if this has been called from an interrupt (via DMAbuf_outputintr)
 * restart_dma  - set if DMA needs to be re-initialised
 *
 * Called when:
 *  1. Starting output                                  (dmabuf.c:1327)
 *  2.                                                  (dmabuf.c:1504)
 *  3. A new buffer needs to be sent to the device      (dmabuf.c:1579)
 */
static void vidc_audio_output_block(int dev, unsigned long buf, int total_count,
			int intrflag)
{
	struct audio_operations *adev = audio_devs[dev];
	struct dma_buffparms *dmap = adev->dmap_out;

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

	if (!(adev->flags & DMA_ACTIVE))
	{
		unsigned long flags;
printk("kicking output: %lX+%lX [%lX]\n", dma_start, dma_count, *(unsigned long *)dma_start);
		save_flags_cli(flags);
		vidc_sound_dma_irq(0, NULL, NULL);
		outb(DMA_CR_E | 0x10, IOMD_SD0CR);
		restore_flags(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 void vidc_audio_dma_interrupt(void)
{
	DMAbuf_outputintr(vidc_adev, 1);
}

/*
 * Prepare for outputting samples to `dev'
 *
 * Each buffer that will be passed will be `bsize' bytes long,
 * with a total of `bcount' buffers.
 *
 * Called when:
 *  1. A trigger enables audio output                   (dmabuf.c:978)
 *  2. We get a write buffer without dma_mode setup     (dmabuf.c:1152)
 *  3. We restart a transfer                            (dmabuf.c:1324)
 */
static int vidc_audio_prepare_for_output(int dev, int bsize, int bcount)
{
	audio_devs[dev]->dmap_out->flags |= DMA_NODMA;
	dma_interrupt = vidc_audio_dma_interrupt;
	return 0;
}

/*
 * Stop our current operation.
 */
static void vidc_audio_reset(int dev)
{
	/* stop interrupts.  Our real interrupt routine
	 * will close DMA down for us
	 */
	dma_interrupt = NULL;
}

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

static struct audio_driver vidc_audio_driver =
{
	vidc_audio_open,		/* open                 */
	vidc_audio_close,		/* close                */
	vidc_audio_output_block,	/* output_block         */
	vidc_audio_start_input,		/* start_input          */
	vidc_audio_ioctl,		/* ioctl                */
	vidc_audio_prepare_for_input,	/* prepare_for_input    */
	vidc_audio_prepare_for_output,	/* prepare_for_output   */
	vidc_audio_reset,		/* reset                */
	vidc_audio_local_qlen,		/*+local_qlen           */
	NULL,				/*+copy_from_user       */
	NULL,				/*+halt_input           */
	NULL,				/* halt_output          */
	NULL,				/*+trigger              */
	NULL,				/*+set_speed            */
	NULL,				/*+set_bits             */
	NULL,				/*+set_channels         */
};

void vidc_audio_init(struct address_info *hw_config)
{
	vidc_audio_volume = 100 | (100 << 8);

	if ((vidc_adev = sound_install_audiodrv(AUDIO_DRIVER_VERSION,
				"VIDCsound", &vidc_audio_driver,
				sizeof(struct audio_driver),
				DMA_AUTOMODE, AFMT_U8 | AFMT_S8 | AFMT_S16_LE,
				NULL, hw_config->dma, hw_config->dma2)) >= 0)
	{
		audio_devs[vidc_adev]->min_fragment = 10;	/* 1024 bytes => 64 buffers */
		audio_devs[vidc_adev]->mixer_dev = num_mixers;
	}
	else printk(KERN_ERR "VIDCsound: Too many PCM devices available\n");
}