/*
 * Guillemot Maxi Radio FM 2000 PCI radio card driver for Linux
 * (C) 2001 Dimitromanolakis Apostolos <apdim@grecian.net>
 *
 * Based in the radio Maestro PCI driver. Actually it uses the same chip
 * for radio but different pci controller.
 *
 * I didn't have any specs I reversed engineered the protocol from
 * the windows driver (radio.dll).
 *
 * The card uses the TEA5757 chip that includes a search function but it
 * is useless as I haven't found any way to read back the frequency. If
 * anybody does please mail me.
 *
 * For the pdf file see:
 * http://www.semiconductors.philips.com/pip/TEA5757H/V1
 *
 *
 * CHANGES:
 *   0.75b
 *     - better pci interface thanks to Francois Romieu <romieu@cogenit.fr>
 *
 *   0.75      Sun Feb  4 22:51:27 EET 2001
 *     - tiding up
 *     - removed support for multiple devices as it didn't work anyway
 *
 * BUGS:
 *   - card unmutes if you change frequency
 *
 * (c) 2006, 2007 by Mauro Carvalho Chehab <mchehab@infradead.org>:
 *	- Conversion to V4L2 API
 *      - Uses video_ioctl2 for parsing and to add debug support
 */


#include <linux/module.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <linux/mutex.h>

#include <linux/pci.h>
#include <linux/videodev2.h>
#include <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>

#define DRIVER_VERSION	"0.77"

#include <linux/version.h>      /* for KERNEL_VERSION MACRO     */
#define RADIO_VERSION KERNEL_VERSION(0,7,7)

static struct video_device maxiradio_radio;

#define dprintk(num, fmt, arg...)                                          \
	do {                                                               \
		if (maxiradio_radio.debug >= num)                          \
			printk(KERN_DEBUG "%s: " fmt,                      \
				maxiradio_radio.name, ## arg); } while (0)

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,
	}
};

#ifndef PCI_VENDOR_ID_GUILLEMOT
#define PCI_VENDOR_ID_GUILLEMOT 0x5046
#endif

#ifndef PCI_DEVICE_ID_GUILLEMOT
#define PCI_DEVICE_ID_GUILLEMOT_MAXIRADIO 0x1001
#endif


/* TEA5757 pin mappings */
static const int clk = 1, data = 2, wren = 4, mo_st = 8, power = 16 ;

static int radio_nr = -1;
module_param(radio_nr, int, 0);

static unsigned long in_use;

#define FREQ_LO		 50*16000
#define FREQ_HI		150*16000

#define FREQ_IF         171200 /* 10.7*16000   */
#define FREQ_STEP       200    /* 12.5*16      */

/* (x==fmhz*16*1000) -> bits */
#define FREQ2BITS(x)	((( (unsigned int)(x)+FREQ_IF+(FREQ_STEP<<1)) \
			/(FREQ_STEP<<2))<<2)

#define BITS2FREQ(x)	((x) * FREQ_STEP - FREQ_IF)


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

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

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

static struct radio_device
{
	__u16	io,	/* base of radio io */
		muted,	/* VIDEO_AUDIO_MUTE */
		stereo,	/* VIDEO_TUNER_STEREO_ON */
		tuned;	/* signal strength (0 or 0xffff) */

	unsigned long freq;

	struct mutex lock;
} radio_unit = {
	.muted =1,
	.freq = FREQ_LO,
};

static void outbit(unsigned long bit, __u16 io)
{
	if (bit != 0)
		{
			outb(  power|wren|data     ,io); udelay(4);
			outb(  power|wren|data|clk ,io); udelay(4);
			outb(  power|wren|data     ,io); udelay(4);
		}
	else
		{
			outb(  power|wren          ,io); udelay(4);
			outb(  power|wren|clk      ,io); udelay(4);
			outb(  power|wren          ,io); udelay(4);
		}
}

static void turn_power(__u16 io, int p)
{
	if (p != 0) {
		dprintk(1, "Radio powered on\n");
		outb(power, io);
	} else {
		dprintk(1, "Radio powered off\n");
		outb(0,io);
	}
}

static void set_freq(__u16 io, __u32 freq)
{
	unsigned long int si;
	int bl;
	int val = FREQ2BITS(freq);

	/* TEA5757 shift register bits (see pdf) */

	outbit(0, io); /* 24  search */
	outbit(1, io); /* 23  search up/down */

	outbit(0, io); /* 22  stereo/mono */

	outbit(0, io); /* 21  band */
	outbit(0, io); /* 20  band (only 00=FM works I think) */

	outbit(0, io); /* 19  port ? */
	outbit(0, io); /* 18  port ? */

	outbit(0, io); /* 17  search level */
	outbit(0, io); /* 16  search level */

	si = 0x8000;
	for (bl = 1; bl <= 16; bl++) {
		outbit(val & si, io);
		si >>= 1;
	}

	dprintk(1, "Radio freq set to %d.%02d MHz\n",
				freq / 16000,
				freq % 16000 * 100 / 16000);

	turn_power(io, 1);
}

static int get_stereo(__u16 io)
{
	outb(power,io);
	udelay(4);

	return !(inb(io) & mo_st);
}

static int get_tune(__u16 io)
{
	outb(power+clk,io);
	udelay(4);

	return !(inb(io) & mo_st);
}


static int vidioc_querycap (struct file *file, void  *priv,
			    struct v4l2_capability *v)
{
	strlcpy(v->driver, "radio-maxiradio", sizeof (v->driver));
	strlcpy(v->card, "Maxi Radio FM2000 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 radio_device *card = video_drvdata(file);

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

	memset(v,0,sizeof(*v));
	strcpy(v->name, "FM");
	v->type = V4L2_TUNER_RADIO;

	v->rangelow=FREQ_LO;
	v->rangehigh=FREQ_HI;
	v->rxsubchans =V4L2_TUNER_SUB_MONO|V4L2_TUNER_SUB_STEREO;
	v->capability=V4L2_TUNER_CAP_LOW;
	if(get_stereo(card->io))
		v->audmode = V4L2_TUNER_MODE_STEREO;
	else
		v->audmode = V4L2_TUNER_MODE_MONO;
	v->signal=0xffff*get_tune(card->io);

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

	strcpy(a->name, "FM");
	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;
}

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

	if (f->frequency < FREQ_LO || f->frequency > FREQ_HI) {
		dprintk(1, "radio freq (%d.%02d MHz) out of range (%d-%d)\n",
					f->frequency / 16000,
					f->frequency % 16000 * 100 / 16000,
					FREQ_LO / 16000, FREQ_HI / 16000);

		return -EINVAL;
	}

	card->freq = f->frequency;
	set_freq(card->io, card->freq);
	msleep(125);

	return 0;
}

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

	f->type = V4L2_TUNER_RADIO;
	f->frequency = card->freq;

	dprintk(4, "radio freq is %d.%02d MHz",
				f->frequency / 16000,
				f->frequency % 16000 * 100 / 16000);

	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 radio_device *card = video_drvdata(file);

	switch (ctrl->id) {
		case V4L2_CID_AUDIO_MUTE:
			ctrl->value=card->muted;
			return (0);
	}

	return -EINVAL;
}

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

	switch (ctrl->id) {
		case V4L2_CID_AUDIO_MUTE:
			card->muted = ctrl->value;
			if(card->muted)
				turn_power(card->io, 0);
			else
				set_freq(card->io, card->freq);
			return 0;
	}

	return -EINVAL;
}

static const struct v4l2_ioctl_ops maxiradio_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 maxiradio_radio = {
	.name		= "Maxi Radio FM2000 radio",
	.fops           = &maxiradio_fops,
	.ioctl_ops 	= &maxiradio_ioctl_ops,
	.release	= video_device_release_empty,
};

static int __devinit maxiradio_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
{
	if(!request_region(pci_resource_start(pdev, 0),
			   pci_resource_len(pdev, 0), "Maxi Radio FM 2000")) {
		printk(KERN_ERR "radio-maxiradio: can't reserve I/O ports\n");
		goto err_out;
	}

	if (pci_enable_device(pdev))
		goto err_out_free_region;

	radio_unit.io = pci_resource_start(pdev, 0);
	mutex_init(&radio_unit.lock);
	video_set_drvdata(&maxiradio_radio, &radio_unit);

	if (video_register_device(&maxiradio_radio, VFL_TYPE_RADIO, radio_nr) < 0) {
		printk("radio-maxiradio: can't register device!");
		goto err_out_free_region;
	}

	printk(KERN_INFO "radio-maxiradio: version "
	       DRIVER_VERSION
	       " time "
	       __TIME__ "  "
	       __DATE__
	       "\n");

	printk(KERN_INFO "radio-maxiradio: found Guillemot MAXI Radio device (io = 0x%x)\n",
	       radio_unit.io);
	return 0;

err_out_free_region:
	release_region(pci_resource_start(pdev, 0), pci_resource_len(pdev, 0));
err_out:
	return -ENODEV;
}

static void __devexit maxiradio_remove_one(struct pci_dev *pdev)
{
	video_unregister_device(&maxiradio_radio);
	release_region(pci_resource_start(pdev, 0), pci_resource_len(pdev, 0));
}

static struct pci_device_id maxiradio_pci_tbl[] = {
	{ PCI_VENDOR_ID_GUILLEMOT, PCI_DEVICE_ID_GUILLEMOT_MAXIRADIO,
		PCI_ANY_ID, PCI_ANY_ID, },
	{ 0,}
};

MODULE_DEVICE_TABLE(pci, maxiradio_pci_tbl);

static struct pci_driver maxiradio_driver = {
	.name		= "radio-maxiradio",
	.id_table	= maxiradio_pci_tbl,
	.probe		= maxiradio_init_one,
	.remove		= __devexit_p(maxiradio_remove_one),
};

static int __init maxiradio_radio_init(void)
{
	return pci_register_driver(&maxiradio_driver);
}

static void __exit maxiradio_radio_exit(void)
{
	pci_unregister_driver(&maxiradio_driver);
}

module_init(maxiradio_radio_init);
module_exit(maxiradio_radio_exit);

MODULE_AUTHOR("Dimitromanolakis Apostolos, apdim@grecian.net");
MODULE_DESCRIPTION("Radio driver for the Guillemot Maxi Radio FM2000 radio.");
MODULE_LICENSE("GPL");

module_param_named(debug,maxiradio_radio.debug, int, 0644);
MODULE_PARM_DESC(debug,"activates debug info");