/*
 ***************************************************************************
 *
 *     radio-gemtek-pci.c - Gemtek PCI Radio driver
 *     (C) 2001 Vladimir Shebordaev <vshebordaev@mail.ru>
 *
 ***************************************************************************
 *
 *     This program is free software; you can redistribute it and/or
 *     modify it under the terms of the GNU General Public License as
 *     published by the Free Software Foundation; either version 2 of
 *     the License, or (at your option) any later version.
 *
 *     This program is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public
 *     License along with this program; if not, write to the Free
 *     Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
 *     USA.
 *
 ***************************************************************************
 *
 *     Gemtek Corp still silently refuses to release any specifications
 *     of their multimedia devices, so the protocol still has to be
 *     reverse engineered.
 *
 *     The v4l code was inspired by Jonas Munsin's  Gemtek serial line
 *     radio device driver.
 *
 *     Please, let me know if this piece of code was useful :)
 *
 *     TODO: multiple device support and portability were not tested
 *
 *     Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@infradead.org>
 *
 ***************************************************************************
 */

#include <linux/types.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/videodev2.h>
#include <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>
#include <linux/errno.h>

#include <linux/version.h>      /* for KERNEL_VERSION MACRO     */
#define RADIO_VERSION KERNEL_VERSION(0,0,2)

static struct v4l2_queryctrl radio_qctrl[] = {
	{
		.id            = V4L2_CID_AUDIO_MUTE,
		.name          = "Mute",
		.minimum       = 0,
		.maximum       = 1,
		.default_value = 1,
		.type          = V4L2_CTRL_TYPE_BOOLEAN,
	},{
		.id            = V4L2_CID_AUDIO_VOLUME,
		.name          = "Volume",
		.minimum       = 0,
		.maximum       = 65535,
		.step          = 65535,
		.default_value = 0xff,
		.type          = V4L2_CTRL_TYPE_INTEGER,
	}
};

#include <asm/io.h>
#include <asm/uaccess.h>

#ifndef PCI_VENDOR_ID_GEMTEK
#define PCI_VENDOR_ID_GEMTEK 0x5046
#endif

#ifndef PCI_DEVICE_ID_GEMTEK_PR103
#define PCI_DEVICE_ID_GEMTEK_PR103 0x1001
#endif

#ifndef GEMTEK_PCI_RANGE_LOW
#define GEMTEK_PCI_RANGE_LOW (87*16000)
#endif

#ifndef GEMTEK_PCI_RANGE_HIGH
#define GEMTEK_PCI_RANGE_HIGH (108*16000)
#endif

struct gemtek_pci_card {
	struct video_device *videodev;

	u32 iobase;
	u32 length;

	u32 current_frequency;
	u8  mute;
};

static int nr_radio = -1;
static unsigned long in_use;

static inline u8 gemtek_pci_out( u16 value, u32 port )
{
	outw( value, port );

	return (u8)value;
}

#define _b0( v ) *((u8 *)&v)
static void __gemtek_pci_cmd( u16 value, u32 port, u8 *last_byte, int keep )
{
	register u8 byte = *last_byte;

	if ( !value ) {
		if ( !keep )
			value = (u16)port;
		byte &= 0xfd;
	} else
		byte |= 2;

	_b0( value ) = byte;
	outw( value, port );
	byte |= 1;
	_b0( value ) = byte;
	outw( value, port );
	byte &= 0xfe;
	_b0( value ) = byte;
	outw( value, port );

	*last_byte = byte;
}

static inline void gemtek_pci_nil( u32 port, u8 *last_byte )
{
	__gemtek_pci_cmd( 0x00, port, last_byte, false );
}

static inline void gemtek_pci_cmd( u16 cmd, u32 port, u8 *last_byte )
{
	__gemtek_pci_cmd( cmd, port, last_byte, true );
}

static void gemtek_pci_setfrequency( struct gemtek_pci_card *card, unsigned long frequency )
{
	register int i;
	register u32 value = frequency / 200 + 856;
	register u16 mask = 0x8000;
	u8 last_byte;
	u32 port = card->iobase;

	last_byte = gemtek_pci_out( 0x06, port );

	i = 0;
	do {
		gemtek_pci_nil( port, &last_byte );
		i++;
	} while ( i < 9 );

	i = 0;
	do {
		gemtek_pci_cmd( value & mask, port, &last_byte );
		mask >>= 1;
		i++;
	} while ( i < 16 );

	outw( 0x10, port );
}


static inline void gemtek_pci_mute( struct gemtek_pci_card *card )
{
	outb( 0x1f, card->iobase );
	card->mute = true;
}

static inline void gemtek_pci_unmute( struct gemtek_pci_card *card )
{
	if ( card->mute ) {
		gemtek_pci_setfrequency( card, card->current_frequency );
		card->mute = false;
	}
}

static inline unsigned int gemtek_pci_getsignal( struct gemtek_pci_card *card )
{
	return ( inb( card->iobase ) & 0x08 ) ? 0 : 1;
}

static int vidioc_querycap(struct file *file, void *priv,
					struct v4l2_capability *v)
{
	strlcpy(v->driver, "radio-gemtek-pci", sizeof(v->driver));
	strlcpy(v->card, "GemTek PCI Radio", sizeof(v->card));
	sprintf(v->bus_info, "ISA");
	v->version = RADIO_VERSION;
	v->capabilities = V4L2_CAP_TUNER;
	return 0;
}

static int vidioc_g_tuner(struct file *file, void *priv,
					struct v4l2_tuner *v)
{
	struct gemtek_pci_card *card = video_drvdata(file);

	if (v->index > 0)
		return -EINVAL;

	strcpy(v->name, "FM");
	v->type = V4L2_TUNER_RADIO;
	v->rangelow = GEMTEK_PCI_RANGE_LOW;
	v->rangehigh = GEMTEK_PCI_RANGE_HIGH;
	v->rxsubchans = V4L2_TUNER_SUB_MONO;
	v->capability = V4L2_TUNER_CAP_LOW;
	v->audmode = V4L2_TUNER_MODE_MONO;
	v->signal = 0xffff * gemtek_pci_getsignal(card);
	return 0;
}

static int vidioc_s_tuner(struct file *file, void *priv,
					struct v4l2_tuner *v)
{
	if (v->index > 0)
		return -EINVAL;
	return 0;
}

static int vidioc_s_frequency(struct file *file, void *priv,
					struct v4l2_frequency *f)
{
	struct gemtek_pci_card *card = video_drvdata(file);

	if ( (f->frequency < GEMTEK_PCI_RANGE_LOW) ||
			(f->frequency > GEMTEK_PCI_RANGE_HIGH) )
		return -EINVAL;
	gemtek_pci_setfrequency(card, f->frequency);
	card->current_frequency = f->frequency;
	card->mute = false;
	return 0;
}

static int vidioc_g_frequency(struct file *file, void *priv,
					struct v4l2_frequency *f)
{
	struct gemtek_pci_card *card = video_drvdata(file);

	f->type = V4L2_TUNER_RADIO;
	f->frequency = card->current_frequency;
	return 0;
}

static int vidioc_queryctrl(struct file *file, void *priv,
					struct v4l2_queryctrl *qc)
{
	int i;
	for (i = 0; i < ARRAY_SIZE(radio_qctrl); i++) {
		if (qc->id && qc->id == radio_qctrl[i].id) {
			memcpy(qc, &(radio_qctrl[i]),
						sizeof(*qc));
			return 0;
		}
	}
	return -EINVAL;
}

static int vidioc_g_ctrl(struct file *file, void *priv,
					struct v4l2_control *ctrl)
{
	struct gemtek_pci_card *card = video_drvdata(file);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
		ctrl->value = card->mute;
		return 0;
	case V4L2_CID_AUDIO_VOLUME:
		if (card->mute)
			ctrl->value = 0;
		else
			ctrl->value = 65535;
		return 0;
	}
	return -EINVAL;
}

static int vidioc_s_ctrl(struct file *file, void *priv,
					struct v4l2_control *ctrl)
{
	struct gemtek_pci_card *card = video_drvdata(file);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
		if (ctrl->value)
			gemtek_pci_mute(card);
		else
			gemtek_pci_unmute(card);
		return 0;
	case V4L2_CID_AUDIO_VOLUME:
		if (ctrl->value)
			gemtek_pci_unmute(card);
		else
			gemtek_pci_mute(card);
		return 0;
	}
	return -EINVAL;
}

static int vidioc_g_audio(struct file *file, void *priv,
					struct v4l2_audio *a)
{
	if (a->index > 1)
		return -EINVAL;

	strcpy(a->name, "Radio");
	a->capability = V4L2_AUDCAP_STEREO;
	return 0;
}

static int vidioc_g_input(struct file *filp, void *priv, unsigned int *i)
{
	*i = 0;
	return 0;
}

static int vidioc_s_input(struct file *filp, void *priv, unsigned int i)
{
	if (i != 0)
		return -EINVAL;
	return 0;
}

static int vidioc_s_audio(struct file *file, void *priv,
					struct v4l2_audio *a)
{
	if (a->index != 0)
		return -EINVAL;
	return 0;
}

enum {
	GEMTEK_PR103
};

static char *card_names[] __devinitdata = {
	"GEMTEK_PR103"
};

static struct pci_device_id gemtek_pci_id[] =
{
	{ PCI_VENDOR_ID_GEMTEK, PCI_DEVICE_ID_GEMTEK_PR103,
	  PCI_ANY_ID, PCI_ANY_ID, 0, 0, GEMTEK_PR103 },
	{ 0 }
};

MODULE_DEVICE_TABLE( pci, gemtek_pci_id );

static int mx = 1;

static int gemtek_pci_exclusive_open(struct inode *inode, struct file *file)
{
	return test_and_set_bit(0, &in_use) ? -EBUSY : 0;
}

static int gemtek_pci_exclusive_release(struct inode *inode, struct file *file)
{
	clear_bit(0, &in_use);
	return 0;
}

static const struct file_operations gemtek_pci_fops = {
	.owner		= THIS_MODULE,
	.open           = gemtek_pci_exclusive_open,
	.release        = gemtek_pci_exclusive_release,
	.ioctl		= video_ioctl2,
#ifdef CONFIG_COMPAT
	.compat_ioctl	= v4l_compat_ioctl32,
#endif
	.llseek         = no_llseek,
};

static const struct v4l2_ioctl_ops gemtek_pci_ioctl_ops = {
	.vidioc_querycap    = vidioc_querycap,
	.vidioc_g_tuner     = vidioc_g_tuner,
	.vidioc_s_tuner     = vidioc_s_tuner,
	.vidioc_g_audio     = vidioc_g_audio,
	.vidioc_s_audio     = vidioc_s_audio,
	.vidioc_g_input     = vidioc_g_input,
	.vidioc_s_input     = vidioc_s_input,
	.vidioc_g_frequency = vidioc_g_frequency,
	.vidioc_s_frequency = vidioc_s_frequency,
	.vidioc_queryctrl   = vidioc_queryctrl,
	.vidioc_g_ctrl      = vidioc_g_ctrl,
	.vidioc_s_ctrl      = vidioc_s_ctrl,
};

static struct video_device vdev_template = {
	.name          	= "Gemtek PCI Radio",
	.fops          	= &gemtek_pci_fops,
	.ioctl_ops 	= &gemtek_pci_ioctl_ops,
	.release	= video_device_release_empty,
};

static int __devinit gemtek_pci_probe( struct pci_dev *pci_dev, const struct pci_device_id *pci_id )
{
	struct gemtek_pci_card *card;
	struct video_device *devradio;

	if ( (card = kzalloc( sizeof( struct gemtek_pci_card ), GFP_KERNEL )) == NULL ) {
		printk( KERN_ERR "gemtek_pci: out of memory\n" );
		return -ENOMEM;
	}

	if ( pci_enable_device( pci_dev ) )
		goto err_pci;

	card->iobase = pci_resource_start( pci_dev, 0 );
	card->length = pci_resource_len( pci_dev, 0 );

	if ( request_region( card->iobase, card->length, card_names[pci_id->driver_data] ) == NULL ) {
		printk( KERN_ERR "gemtek_pci: i/o port already in use\n" );
		goto err_pci;
	}

	pci_set_drvdata( pci_dev, card );

	if ( (devradio = kmalloc( sizeof( struct video_device ), GFP_KERNEL )) == NULL ) {
		printk( KERN_ERR "gemtek_pci: out of memory\n" );
		goto err_video;
	}
	*devradio = vdev_template;

	if (video_register_device(devradio, VFL_TYPE_RADIO, nr_radio) < 0) {
		kfree( devradio );
		goto err_video;
	}

	card->videodev = devradio;
	video_set_drvdata(devradio, card);
	gemtek_pci_mute( card );

	printk( KERN_INFO "Gemtek PCI Radio (rev. %d) found at 0x%04x-0x%04x.\n",
		pci_dev->revision, card->iobase, card->iobase + card->length - 1 );

	return 0;

err_video:
	release_region( card->iobase, card->length );

err_pci:
	kfree( card );
	return -ENODEV;
}

static void __devexit gemtek_pci_remove( struct pci_dev *pci_dev )
{
	struct gemtek_pci_card *card = pci_get_drvdata( pci_dev );

	video_unregister_device( card->videodev );
	kfree( card->videodev );

	release_region( card->iobase, card->length );

	if ( mx )
		gemtek_pci_mute( card );

	kfree( card );

	pci_set_drvdata( pci_dev, NULL );
}

static struct pci_driver gemtek_pci_driver =
{
	.name		= "gemtek_pci",
	.id_table	= gemtek_pci_id,
	.probe		= gemtek_pci_probe,
	.remove		= __devexit_p(gemtek_pci_remove),
};

static int __init gemtek_pci_init_module( void )
{
	return pci_register_driver( &gemtek_pci_driver );
}

static void __exit gemtek_pci_cleanup_module( void )
{
	pci_unregister_driver(&gemtek_pci_driver);
}

MODULE_AUTHOR( "Vladimir Shebordaev <vshebordaev@mail.ru>" );
MODULE_DESCRIPTION( "The video4linux driver for the Gemtek PCI Radio Card" );
MODULE_LICENSE("GPL");

module_param(mx, bool, 0);
MODULE_PARM_DESC( mx, "single digit: 1 - turn off the turner upon module exit (default), 0 - do not" );
module_param(nr_radio, int, 0);
MODULE_PARM_DESC( nr_radio, "video4linux device number to use");

module_init( gemtek_pci_init_module );
module_exit( gemtek_pci_cleanup_module );