/* SF16-FMI and SF16-FMP radio driver for Linux radio support

   * heavily based on rtrack driver...
   * (c) 1997 M. Kirkwood
   * (c) 1998 Petr Vandrovec, vandrove@vc.cvut.cz
   *

   * Fitted to new interface by Alan Cox <alan@lxorguk.ukuu.org.uk>

   * Made working and cleaned up functions <mikael.hedin@irf.se>
   * Support for ISAPnP by Ladislav Michl <ladis@psi.cz>
   *
   * Notes on the hardware
   *
   *  Frequency control is done digitally -- ie out(port,encodefreq(95.8));
   *  No volume control - only mute/unmute - you have to use line volume

   *  control on SB-part of SF16-FMI/SF16-FMP

   *

   * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@infradead.org>

   */
  
  #include <linux/kernel.h>	/* __setup			*/
  #include <linux/module.h>	/* Modules 			*/
  #include <linux/init.h>		/* Initdata			*/

  #include <linux/ioport.h>	/* request_region		*/

  #include <linux/delay.h>	/* udelay			*/

  #include <linux/isapnp.h>

  #include <linux/mutex.h>

  #include <linux/videodev2.h>	/* kernel radio structs		*/
  #include <linux/io.h>		/* outb, outb_p			*/

  #include <media/v4l2-device.h>
  #include <media/v4l2-ioctl.h>

  MODULE_AUTHOR("Petr Vandrovec, vandrove@vc.cvut.cz and M. Kirkwood");

  MODULE_DESCRIPTION("A driver for the SF16-FMI and SF16-FMP radio.");

  MODULE_LICENSE("GPL");

  MODULE_VERSION("0.0.3");

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

  MODULE_PARM_DESC(io, "I/O address of the SF16-FMI or SF16-FMP card (0x284 or 0x384)");

  module_param(radio_nr, int, 0);

  struct fmi

  {

  	struct v4l2_device v4l2_dev;
  	struct video_device vdev;
  	int io;

  	bool mute;

  	unsigned long curfreq; /* freq in kHz */

  	struct mutex lock;

  };

  static struct fmi fmi_card;
  static struct pnp_dev *dev;

  bool pnp_attached;

  
  /* freq is in 1/16 kHz to internal number, hw precision is 50 kHz */

  /* It is only useful to give freq in interval of 800 (=0.05Mhz),

   * other bits will be truncated, e.g 92.7400016 -> 92.7, but

   * 92.7400017 -> 92.75
   */

  #define RSF16_ENCODE(x)	((x) / 800 + 214)
  #define RSF16_MINFREQ (87 * 16000)
  #define RSF16_MAXFREQ (108 * 16000)

  static void outbits(int bits, unsigned int data, int io)

  {

  	while (bits--) {
  		if (data & 1) {
  			outb(5, io);

  			udelay(6);

  			outb(7, io);

  			udelay(6);
  		} else {

  			outb(1, io);

  			udelay(6);

  			outb(3, io);

  			udelay(6);
  		}

  		data >>= 1;

  	}
  }

  static inline void fmi_mute(struct fmi *fmi)

  {

  	mutex_lock(&fmi->lock);
  	outb(0x00, fmi->io);
  	mutex_unlock(&fmi->lock);

  }

  static inline void fmi_unmute(struct fmi *fmi)

  {

  	mutex_lock(&fmi->lock);
  	outb(0x08, fmi->io);
  	mutex_unlock(&fmi->lock);

  }

  static inline int fmi_setfreq(struct fmi *fmi, unsigned long freq)

  {

  	mutex_lock(&fmi->lock);
  	fmi->curfreq = freq;

  	outbits(16, RSF16_ENCODE(freq), fmi->io);
  	outbits(8, 0xC0, fmi->io);

  	msleep(143);		/* was schedule_timeout(HZ/7) */

  	mutex_unlock(&fmi->lock);

  	if (!fmi->mute)

  		fmi_unmute(fmi);

  	return 0;
  }

  static inline int fmi_getsigstr(struct fmi *fmi)

  {
  	int val;
  	int res;

  	mutex_lock(&fmi->lock);

  	val = fmi->mute ? 0x00 : 0x08;	/* mute/unmute */

  	outb(val, fmi->io);
  	outb(val | 0x10, fmi->io);

  	msleep(143); 		/* was schedule_timeout(HZ/7) */

  	res = (int)inb(fmi->io + 1);
  	outb(val, fmi->io);

  	mutex_unlock(&fmi->lock);

  	return (res & 2) ? 0 : 0xFFFF;
  }

  static int vidioc_querycap(struct file *file, void  *priv,
  					struct v4l2_capability *v)

  {

  	strlcpy(v->driver, "radio-sf16fmi", sizeof(v->driver));
  	strlcpy(v->card, "SF16-FMx radio", sizeof(v->card));

  	strlcpy(v->bus_info, "ISA", sizeof(v->bus_info));

  	v->capabilities = V4L2_CAP_TUNER | V4L2_CAP_RADIO;

  	return 0;
  }
  
  static int vidioc_g_tuner(struct file *file, void *priv,
  					struct v4l2_tuner *v)
  {

  	struct fmi *fmi = video_drvdata(file);

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

  	strlcpy(v->name, "FM", sizeof(v->name));

  	v->type = V4L2_TUNER_RADIO;

  	v->rangelow = RSF16_MINFREQ;
  	v->rangehigh = RSF16_MAXFREQ;

  	v->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO;

  	v->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_LOW;

  	v->audmode = V4L2_TUNER_MODE_STEREO;
  	v->signal = fmi_getsigstr(fmi);
  	return 0;
  }

  static int vidioc_s_tuner(struct file *file, void *priv,
  					struct v4l2_tuner *v)
  {

  	return v->index ? -EINVAL : 0;

  }

  static int vidioc_s_frequency(struct file *file, void *priv,
  					struct v4l2_frequency *f)
  {

  	struct fmi *fmi = video_drvdata(file);

  	if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
  		return -EINVAL;

  	if (f->frequency < RSF16_MINFREQ ||

  			f->frequency > RSF16_MAXFREQ)

  		return -EINVAL;

  	/* rounding in steps of 800 to match the freq
  	   that will be used */
  	fmi_setfreq(fmi, (f->frequency / 800) * 800);

  	return 0;
  }

  static int vidioc_g_frequency(struct file *file, void *priv,
  					struct v4l2_frequency *f)
  {

  	struct fmi *fmi = video_drvdata(file);

  	if (f->tuner != 0)
  		return -EINVAL;

  	f->type = V4L2_TUNER_RADIO;
  	f->frequency = fmi->curfreq;

  	return 0;
  }

  static int vidioc_queryctrl(struct file *file, void *priv,
  					struct v4l2_queryctrl *qc)
  {

  	switch (qc->id) {
  	case V4L2_CID_AUDIO_MUTE:
  		return v4l2_ctrl_query_fill(qc, 0, 1, 1, 1);

  	}
  	return -EINVAL;
  }

  static int vidioc_g_ctrl(struct file *file, void *priv,
  					struct v4l2_control *ctrl)
  {

  	struct fmi *fmi = video_drvdata(file);

  	switch (ctrl->id) {
  	case V4L2_CID_AUDIO_MUTE:

  		ctrl->value = fmi->mute;

  		return 0;

  	}

  	return -EINVAL;
  }
  
  static int vidioc_s_ctrl(struct file *file, void *priv,
  					struct v4l2_control *ctrl)
  {

  	struct fmi *fmi = video_drvdata(file);

  
  	switch (ctrl->id) {
  	case V4L2_CID_AUDIO_MUTE:
  		if (ctrl->value)

  			fmi_mute(fmi);

  		else

  			fmi_unmute(fmi);

  		fmi->mute = ctrl->value;

  		return 0;
  	}
  	return -EINVAL;
  }

  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)
  {

  	return i ? -EINVAL : 0;

  }

  static int vidioc_g_audio(struct file *file, void *priv,

  					struct v4l2_audio *a)
  {

  	a->index = 0;
  	strlcpy(a->name, "Radio", sizeof(a->name));
  	a->capability = V4L2_AUDCAP_STEREO;

  	return 0;

  }

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

  static const struct v4l2_file_operations fmi_fops = {

  	.owner		= THIS_MODULE,

  	.unlocked_ioctl	= video_ioctl2,

  };

  static const struct v4l2_ioctl_ops fmi_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,

  };
  
  /* ladis: this is my card. does any other types exist? */
  static struct isapnp_device_id id_table[] __devinitdata = {
  	{	ISAPNP_ANY_ID, ISAPNP_ANY_ID,
  		ISAPNP_VENDOR('M','F','R'), ISAPNP_FUNCTION(0xad10), 0},
  	{	ISAPNP_CARD_END, },
  };
  
  MODULE_DEVICE_TABLE(isapnp, id_table);

  static int __init isapnp_fmi_probe(void)

  {
  	int i = 0;
  
  	while (id_table[i].card_vendor != 0 && dev == NULL) {
  		dev = pnp_find_dev(NULL, id_table[i].vendor,
  				   id_table[i].function, NULL);
  		i++;
  	}
  
  	if (!dev)
  		return -ENODEV;
  	if (pnp_device_attach(dev) < 0)
  		return -EAGAIN;
  	if (pnp_activate_dev(dev) < 0) {

  		printk(KERN_ERR "radio-sf16fmi: PnP configure failed (out of resources?)
  ");

  		pnp_device_detach(dev);
  		return -ENOMEM;
  	}
  	if (!pnp_port_valid(dev, 0)) {
  		pnp_device_detach(dev);
  		return -ENODEV;
  	}
  
  	i = pnp_port_start(dev, 0);

  	printk(KERN_INFO "radio-sf16fmi: PnP reports card at %#x
  ", i);

  
  	return i;
  }
  
  static int __init fmi_init(void)
  {

  	struct fmi *fmi = &fmi_card;
  	struct v4l2_device *v4l2_dev = &fmi->v4l2_dev;

  	int res, i;
  	int probe_ports[] = { 0, 0x284, 0x384 };
  
  	if (io < 0) {
  		for (i = 0; i < ARRAY_SIZE(probe_ports); i++) {
  			io = probe_ports[i];
  			if (io == 0) {
  				io = isapnp_fmi_probe();
  				if (io < 0)
  					continue;
  				pnp_attached = 1;
  			}
  			if (!request_region(io, 2, "radio-sf16fmi")) {
  				if (pnp_attached)
  					pnp_device_detach(dev);
  				io = -1;
  				continue;
  			}
  			if (pnp_attached ||
  			    ((inb(io) & 0xf9) == 0xf9 && (inb(io) & 0x4) == 0))
  				break;
  			release_region(io, 2);
  			io = -1;
  		}
  	} else {
  		if (!request_region(io, 2, "radio-sf16fmi")) {
  			printk(KERN_ERR "radio-sf16fmi: port %#x already in use
  ", io);
  			return -EBUSY;
  		}
  		if (inb(io) == 0xff) {
  			printk(KERN_ERR "radio-sf16fmi: card not present at %#x
  ", io);
  			release_region(io, 2);
  			return -ENODEV;
  		}
  	}
  	if (io < 0) {
  		printk(KERN_ERR "radio-sf16fmi: no cards found
  ");
  		return -ENODEV;
  	}

  	strlcpy(v4l2_dev->name, "sf16fmi", sizeof(v4l2_dev->name));
  	fmi->io = io;

  	res = v4l2_device_register(NULL, v4l2_dev);
  	if (res < 0) {
  		release_region(fmi->io, 2);

  		if (pnp_attached)
  			pnp_device_detach(dev);

  		v4l2_err(v4l2_dev, "Could not register v4l2_device
  ");
  		return res;
  	}

  	strlcpy(fmi->vdev.name, v4l2_dev->name, sizeof(fmi->vdev.name));
  	fmi->vdev.v4l2_dev = v4l2_dev;
  	fmi->vdev.fops = &fmi_fops;
  	fmi->vdev.ioctl_ops = &fmi_ioctl_ops;
  	fmi->vdev.release = video_device_release_empty;
  	video_set_drvdata(&fmi->vdev, fmi);

  	mutex_init(&fmi->lock);

  	/* mute card - prevents noisy bootups */
  	fmi_mute(fmi);

  	if (video_register_device(&fmi->vdev, VFL_TYPE_RADIO, radio_nr) < 0) {
  		v4l2_device_unregister(v4l2_dev);
  		release_region(fmi->io, 2);

  		if (pnp_attached)
  			pnp_device_detach(dev);

  		return -EINVAL;
  	}

  	v4l2_info(v4l2_dev, "card driver at 0x%x
  ", fmi->io);

  	return 0;
  }

  static void __exit fmi_exit(void)

  {

  	struct fmi *fmi = &fmi_card;
  
  	video_unregister_device(&fmi->vdev);
  	v4l2_device_unregister(&fmi->v4l2_dev);
  	release_region(fmi->io, 2);

  	if (dev && pnp_attached)

  		pnp_device_detach(dev);
  }
  
  module_init(fmi_init);

  module_exit(fmi_exit);