drivers/media/radio/radio-zoltrix.c - maze/linux - Git at Google

 /* zoltrix radio plus driver for Linux radio support
  * (c) 1998 C. van Schaik <carl@leg.uct.ac.za>
  *
  * BUGS
  *  Due to the inconsistency in reading from the signal flags
  *  it is difficult to get an accurate tuned signal.
  *
  *  It seems that the card is not linear to 0 volume. It cuts off
  *  at a low volume, and it is not possible (at least I have not found)
  *  to get fine volume control over the low volume range.
  *
  *  Some code derived from code by Romolo Manfredini
  *				   romolo@bicnet.it
  *
  * 1999-05-06 - (C. van Schaik)
  *	      - Make signal strength and stereo scans
  *		kinder to cpu while in delay
  * 1999-01-05 - (C. van Schaik)
  *	      - Changed tuning to 1/160Mhz accuracy
  *	      - Added stereo support
  *		(card defaults to stereo)
  *		(can explicitly force mono on the card)
  *		(can detect if station is in stereo)
  *	      - Added unmute function
  *	      - Reworked ioctl functions
  * 2002-07-15 - Fix Stereo typo
  *
  * 2006-07-24 - Converted to V4L2 API
  *		by Mauro Carvalho Chehab <mchehab@infradead.org>
  */

 #include <linux/module.h>	/* Modules                        */
 #include <linux/init.h>		/* Initdata                       */
 #include <linux/ioport.h>	/* request_region		  */
 #include <linux/delay.h>	/* udelay, msleep                 */
 #include <linux/videodev2.h>	/* kernel radio structs           */
 #include <linux/mutex.h>
 #include <linux/version.h>      /* for KERNEL_VERSION MACRO     */
 #include <linux/io.h>		/* outb, outb_p                   */
 #include <media/v4l2-device.h>
 #include <media/v4l2-ioctl.h>

 MODULE_AUTHOR("C.van Schaik");
 MODULE_DESCRIPTION("A driver for the Zoltrix Radio Plus.");
 MODULE_LICENSE("GPL");

 #ifndef CONFIG_RADIO_ZOLTRIX_PORT
 #define CONFIG_RADIO_ZOLTRIX_PORT -1
 #endif

 static int io = CONFIG_RADIO_ZOLTRIX_PORT;
 static int radio_nr = -1;

 module_param(io, int, 0);
 MODULE_PARM_DESC(io, "I/O address of the Zoltrix Radio Plus (0x20c or 0x30c)");
 module_param(radio_nr, int, 0);

 #define RADIO_VERSION KERNEL_VERSION(0, 0, 2)

 struct zoltrix {
 	struct v4l2_device v4l2_dev;
 	struct video_device vdev;
 	int io;
 	int curvol;
 	unsigned long curfreq;
 	int muted;
 	unsigned int stereo;
 	struct mutex lock;
 };

 static struct zoltrix zoltrix_card;

 static int zol_setvol(struct zoltrix *zol, int vol)
 {
 	zol->curvol = vol;
 	if (zol->muted)
 		return 0;

 	mutex_lock(&zol->lock);
 	if (vol == 0) {
 		outb(0, zol->io);
 		outb(0, zol->io);
 		inb(zol->io + 3);    /* Zoltrix needs to be read to confirm */
 		mutex_unlock(&zol->lock);
 		return 0;
 	}

 	outb(zol->curvol-1, zol->io);
 	msleep(10);
 	inb(zol->io + 2);
 	mutex_unlock(&zol->lock);
 	return 0;
 }

 static void zol_mute(struct zoltrix *zol)
 {
 	zol->muted = 1;
 	mutex_lock(&zol->lock);
 	outb(0, zol->io);
 	outb(0, zol->io);
 	inb(zol->io + 3);            /* Zoltrix needs to be read to confirm */
 	mutex_unlock(&zol->lock);
 }

 static void zol_unmute(struct zoltrix *zol)
 {
 	zol->muted = 0;
 	zol_setvol(zol, zol->curvol);
 }

 static int zol_setfreq(struct zoltrix *zol, unsigned long freq)
 {
 	/* tunes the radio to the desired frequency */
 	struct v4l2_device *v4l2_dev = &zol->v4l2_dev;
 	unsigned long long bitmask, f, m;
 	unsigned int stereo = zol->stereo;
 	int i;

 	if (freq == 0) {
 		v4l2_warn(v4l2_dev, "cannot set a frequency of 0.\n");
 		return -EINVAL;
 	}

 	m = (freq / 160 - 8800) * 2;
 	f = (unsigned long long)m + 0x4d1c;

 	bitmask = 0xc480402c10080000ull;
 	i = 45;

 	mutex_lock(&zol->lock);

 	zol->curfreq = freq;

 	outb(0, zol->io);
 	outb(0, zol->io);
 	inb(zol->io + 3);            /* Zoltrix needs to be read to confirm */

 	outb(0x40, zol->io);
 	outb(0xc0, zol->io);

 	bitmask = (bitmask ^ ((f & 0xff) << 47) ^ ((f & 0xff00) << 30) ^ (stereo << 31));
 	while (i--) {
 		if ((bitmask & 0x8000000000000000ull) != 0) {
 			outb(0x80, zol->io);
 			udelay(50);
 			outb(0x00, zol->io);
 			udelay(50);
 			outb(0x80, zol->io);
 			udelay(50);
 		} else {
 			outb(0xc0, zol->io);
 			udelay(50);
 			outb(0x40, zol->io);
 			udelay(50);
 			outb(0xc0, zol->io);
 			udelay(50);
 		}
 		bitmask *= 2;
 	}
 	/* termination sequence */
 	outb(0x80, zol->io);
 	outb(0xc0, zol->io);
 	outb(0x40, zol->io);
 	udelay(1000);
 	inb(zol->io + 2);

 	udelay(1000);

 	if (zol->muted) {
 		outb(0, zol->io);
 		outb(0, zol->io);
 		inb(zol->io + 3);
 		udelay(1000);
 	}

 	mutex_unlock(&zol->lock);

 	if (!zol->muted)
 		zol_setvol(zol, zol->curvol);
 	return 0;
 }

 /* Get signal strength */
 static int zol_getsigstr(struct zoltrix *zol)
 {
 	int a, b;

 	mutex_lock(&zol->lock);
 	outb(0x00, zol->io);         /* This stuff I found to do nothing */
 	outb(zol->curvol, zol->io);
 	msleep(20);

 	a = inb(zol->io);
 	msleep(10);
 	b = inb(zol->io);

 	mutex_unlock(&zol->lock);

 	if (a != b)
 		return 0;

 	/* I found this out by playing with a binary scanner on the card io */
 	return a == 0xcf || a == 0xdf || a == 0xef;
 }

 static int zol_is_stereo(struct zoltrix *zol)
 {
 	int x1, x2;

 	mutex_lock(&zol->lock);

 	outb(0x00, zol->io);
 	outb(zol->curvol, zol->io);
 	msleep(20);

 	x1 = inb(zol->io);
 	msleep(10);
 	x2 = inb(zol->io);

 	mutex_unlock(&zol->lock);

 	return x1 == x2 && x1 == 0xcf;
 }

 static int vidioc_querycap(struct file *file, void  *priv,
 					struct v4l2_capability *v)
 {
 	strlcpy(v->driver, "radio-zoltrix", sizeof(v->driver));
 	strlcpy(v->card, "Zoltrix Radio", sizeof(v->card));
 	strlcpy(v->bus_info, "ISA", sizeof(v->bus_info));
 	v->version = RADIO_VERSION;
 	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 zoltrix *zol = video_drvdata(file);

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

 	strlcpy(v->name, "FM", sizeof(v->name));
 	v->type = V4L2_TUNER_RADIO;
 	v->rangelow = 88 * 16000;
 	v->rangehigh = 108 * 16000;
 	v->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO;
 	v->capability = V4L2_TUNER_CAP_LOW;
 	if (zol_is_stereo(zol))
 		v->audmode = V4L2_TUNER_MODE_STEREO;
 	else
 		v->audmode = V4L2_TUNER_MODE_MONO;
 	v->signal = 0xFFFF * zol_getsigstr(zol);
 	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 zoltrix *zol = video_drvdata(file);

 	if (zol_setfreq(zol, f->frequency) != 0)
 		return -EINVAL;
 	return 0;
 }

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

 	f->type = V4L2_TUNER_RADIO;
 	f->frequency = zol->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);
 	case V4L2_CID_AUDIO_VOLUME:
 		return v4l2_ctrl_query_fill(qc, 0, 65535, 4096, 65535);
 	}
 	return -EINVAL;
 }

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

 	switch (ctrl->id) {
 	case V4L2_CID_AUDIO_MUTE:
 		ctrl->value = zol->muted;
 		return 0;
 	case V4L2_CID_AUDIO_VOLUME:
 		ctrl->value = zol->curvol * 4096;
 		return 0;
 	}
 	return -EINVAL;
 }

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

 	switch (ctrl->id) {
 	case V4L2_CID_AUDIO_MUTE:
 		if (ctrl->value)
 			zol_mute(zol);
 		else {
 			zol_unmute(zol);
 			zol_setvol(zol, zol->curvol);
 		}
 		return 0;
 	case V4L2_CID_AUDIO_VOLUME:
 		zol_setvol(zol, ctrl->value / 4096);
 		return 0;
 	}
 	zol->stereo = 1;
 	if (zol_setfreq(zol, zol->curfreq) != 0)
 		return -EINVAL;
 #if 0
 /* FIXME: Implement stereo/mono switch on V4L2 */
 	if (v->mode & VIDEO_SOUND_STEREO) {
 		zol->stereo = 1;
 		zol_setfreq(zol, zol->curfreq);
 	}
 	if (v->mode & VIDEO_SOUND_MONO) {
 		zol->stereo = 0;
 		zol_setfreq(zol, zol->curfreq);
 	}
 #endif
 	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 int zoltrix_open(struct file *file)
 {
 	return 0;
 }

 static int zoltrix_release(struct file *file)
 {
 	return 0;
 }

 static const struct v4l2_file_operations zoltrix_fops =
 {
 	.owner		= THIS_MODULE,
 	.open           = zoltrix_open,
 	.release        = zoltrix_release,
 	.ioctl		= video_ioctl2,
 };

 static const struct v4l2_ioctl_ops zoltrix_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 int __init zoltrix_init(void)
 {
 	struct zoltrix *zol = &zoltrix_card;
 	struct v4l2_device *v4l2_dev = &zol->v4l2_dev;
 	int res;

 	strlcpy(v4l2_dev->name, "zoltrix", sizeof(v4l2_dev->name));
 	zol->io = io;
 	if (zol->io == -1) {
 		v4l2_err(v4l2_dev, "You must set an I/O address with io=0x20c or 0x30c\n");
 		return -EINVAL;
 	}
 	if (zol->io != 0x20c && zol->io != 0x30c) {
 		v4l2_err(v4l2_dev, "invalid port, try 0x20c or 0x30c\n");
 		return -ENXIO;
 	}

 	if (!request_region(zol->io, 2, "zoltrix")) {
 		v4l2_err(v4l2_dev, "port 0x%x already in use\n", zol->io);
 		return -EBUSY;
 	}

 	res = v4l2_device_register(NULL, v4l2_dev);
 	if (res < 0) {
 		release_region(zol->io, 2);
 		v4l2_err(v4l2_dev, "Could not register v4l2_device\n");
 		return res;
 	}

 	strlcpy(zol->vdev.name, v4l2_dev->name, sizeof(zol->vdev.name));
 	zol->vdev.v4l2_dev = v4l2_dev;
 	zol->vdev.fops = &zoltrix_fops;
 	zol->vdev.ioctl_ops = &zoltrix_ioctl_ops;
 	zol->vdev.release = video_device_release_empty;
 	video_set_drvdata(&zol->vdev, zol);

 	if (video_register_device(&zol->vdev, VFL_TYPE_RADIO, radio_nr) < 0) {
 		v4l2_device_unregister(v4l2_dev);
 		release_region(zol->io, 2);
 		return -EINVAL;
 	}
 	v4l2_info(v4l2_dev, "Zoltrix Radio Plus card driver.\n");

 	mutex_init(&zol->lock);

 	/* mute card - prevents noisy bootups */

 	/* this ensures that the volume is all the way down  */

 	outb(0, zol->io);
 	outb(0, zol->io);
 	msleep(20);
 	inb(zol->io + 3);

 	zol->curvol = 0;
 	zol->stereo = 1;

 	return 0;
 }

 static void __exit zoltrix_exit(void)
 {
 	struct zoltrix *zol = &zoltrix_card;

 	video_unregister_device(&zol->vdev);
 	v4l2_device_unregister(&zol->v4l2_dev);
 	release_region(zol->io, 2);
 }

 module_init(zoltrix_init);
 module_exit(zoltrix_exit);
	/* zoltrix radio plus driver for Linux radio support
	* (c) 1998 C. van Schaik <carl@leg.uct.ac.za>
	*
	* BUGS
	* Due to the inconsistency in reading from the signal flags
	* it is difficult to get an accurate tuned signal.
	*
	* It seems that the card is not linear to 0 volume. It cuts off
	* at a low volume, and it is not possible (at least I have not found)
	* to get fine volume control over the low volume range.
	*
	* Some code derived from code by Romolo Manfredini
	* romolo@bicnet.it
	*
	* 1999-05-06 - (C. van Schaik)
	* - Make signal strength and stereo scans
	* kinder to cpu while in delay
	* 1999-01-05 - (C. van Schaik)
	* - Changed tuning to 1/160Mhz accuracy
	* - Added stereo support
	* (card defaults to stereo)
	* (can explicitly force mono on the card)
	* (can detect if station is in stereo)
	* - Added unmute function
	* - Reworked ioctl functions
	* 2002-07-15 - Fix Stereo typo
	*
	* 2006-07-24 - Converted to V4L2 API
	* by Mauro Carvalho Chehab <mchehab@infradead.org>
	*/

	#include <linux/module.h> /* Modules */
	#include <linux/init.h> /* Initdata */
	#include <linux/ioport.h> /* request_region */
	#include <linux/delay.h> /* udelay, msleep */
	#include <linux/videodev2.h> /* kernel radio structs */
	#include <linux/mutex.h>
	#include <linux/version.h> /* for KERNEL_VERSION MACRO */
	#include <linux/io.h> /* outb, outb_p */
	#include <media/v4l2-device.h>
	#include <media/v4l2-ioctl.h>

	MODULE_AUTHOR("C.van Schaik");
	MODULE_DESCRIPTION("A driver for the Zoltrix Radio Plus.");
	MODULE_LICENSE("GPL");

	#ifndef CONFIG_RADIO_ZOLTRIX_PORT
	#define CONFIG_RADIO_ZOLTRIX_PORT -1
	#endif

	static int io = CONFIG_RADIO_ZOLTRIX_PORT;
	static int radio_nr = -1;

	module_param(io, int, 0);
	MODULE_PARM_DESC(io, "I/O address of the Zoltrix Radio Plus (0x20c or 0x30c)");
	module_param(radio_nr, int, 0);

	#define RADIO_VERSION KERNEL_VERSION(0, 0, 2)

	struct zoltrix {
	struct v4l2_device v4l2_dev;
	struct video_device vdev;
	int io;
	int curvol;
	unsigned long curfreq;
	int muted;
	unsigned int stereo;
	struct mutex lock;
	};

	static struct zoltrix zoltrix_card;

	static int zol_setvol(struct zoltrix *zol, int vol)
	{
	zol->curvol = vol;
	if (zol->muted)
	return 0;

	mutex_lock(&zol->lock);
	if (vol == 0) {
	outb(0, zol->io);
	outb(0, zol->io);
	inb(zol->io + 3); /* Zoltrix needs to be read to confirm */
	mutex_unlock(&zol->lock);
	return 0;
	}

	outb(zol->curvol-1, zol->io);
	msleep(10);
	inb(zol->io + 2);
	mutex_unlock(&zol->lock);
	return 0;
	}

	static void zol_mute(struct zoltrix *zol)
	{
	zol->muted = 1;
	mutex_lock(&zol->lock);
	outb(0, zol->io);
	outb(0, zol->io);
	inb(zol->io + 3); /* Zoltrix needs to be read to confirm */
	mutex_unlock(&zol->lock);
	}

	static void zol_unmute(struct zoltrix *zol)
	{
	zol->muted = 0;
	zol_setvol(zol, zol->curvol);
	}

	static int zol_setfreq(struct zoltrix *zol, unsigned long freq)
	{
	/* tunes the radio to the desired frequency */
	struct v4l2_device *v4l2_dev = &zol->v4l2_dev;
	unsigned long long bitmask, f, m;
	unsigned int stereo = zol->stereo;
	int i;

	if (freq == 0) {
	v4l2_warn(v4l2_dev, "cannot set a frequency of 0.\n");
	return -EINVAL;
	}

	m = (freq / 160 - 8800) * 2;
	f = (unsigned long long)m + 0x4d1c;

	bitmask = 0xc480402c10080000ull;
	i = 45;

	mutex_lock(&zol->lock);

	zol->curfreq = freq;

	outb(0, zol->io);
	outb(0, zol->io);
	inb(zol->io + 3); /* Zoltrix needs to be read to confirm */

	outb(0x40, zol->io);
	outb(0xc0, zol->io);

	bitmask = (bitmask ^ ((f & 0xff) << 47) ^ ((f & 0xff00) << 30) ^ (stereo << 31));
	while (i--) {
	if ((bitmask & 0x8000000000000000ull) != 0) {
	outb(0x80, zol->io);
	udelay(50);
	outb(0x00, zol->io);
	udelay(50);
	outb(0x80, zol->io);
	udelay(50);
	} else {
	outb(0xc0, zol->io);
	udelay(50);
	outb(0x40, zol->io);
	udelay(50);
	outb(0xc0, zol->io);
	udelay(50);
	}
	bitmask *= 2;
	}
	/* termination sequence */
	outb(0x80, zol->io);
	outb(0xc0, zol->io);
	outb(0x40, zol->io);
	udelay(1000);
	inb(zol->io + 2);

	udelay(1000);

	if (zol->muted) {
	outb(0, zol->io);
	outb(0, zol->io);
	inb(zol->io + 3);
	udelay(1000);
	}

	mutex_unlock(&zol->lock);

	if (!zol->muted)
	zol_setvol(zol, zol->curvol);
	return 0;
	}

	/* Get signal strength */
	static int zol_getsigstr(struct zoltrix *zol)
	{
	int a, b;

	mutex_lock(&zol->lock);
	outb(0x00, zol->io); /* This stuff I found to do nothing */
	outb(zol->curvol, zol->io);
	msleep(20);

	a = inb(zol->io);
	msleep(10);
	b = inb(zol->io);

	mutex_unlock(&zol->lock);

	if (a != b)
	return 0;

	/* I found this out by playing with a binary scanner on the card io */
	return a == 0xcf \|\| a == 0xdf \|\| a == 0xef;
	}

	static int zol_is_stereo(struct zoltrix *zol)
	{
	int x1, x2;

	mutex_lock(&zol->lock);

	outb(0x00, zol->io);
	outb(zol->curvol, zol->io);
	msleep(20);

	x1 = inb(zol->io);
	msleep(10);
	x2 = inb(zol->io);

	mutex_unlock(&zol->lock);

	return x1 == x2 && x1 == 0xcf;
	}

	static int vidioc_querycap(struct file file, void priv,
	struct v4l2_capability *v)
	{
	strlcpy(v->driver, "radio-zoltrix", sizeof(v->driver));
	strlcpy(v->card, "Zoltrix Radio", sizeof(v->card));
	strlcpy(v->bus_info, "ISA", sizeof(v->bus_info));
	v->version = RADIO_VERSION;
	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 zoltrix *zol = video_drvdata(file);

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

	strlcpy(v->name, "FM", sizeof(v->name));
	v->type = V4L2_TUNER_RADIO;
	v->rangelow = 88 * 16000;
	v->rangehigh = 108 * 16000;
	v->rxsubchans = V4L2_TUNER_SUB_MONO \| V4L2_TUNER_SUB_STEREO;
	v->capability = V4L2_TUNER_CAP_LOW;
	if (zol_is_stereo(zol))
	v->audmode = V4L2_TUNER_MODE_STEREO;
	else
	v->audmode = V4L2_TUNER_MODE_MONO;
	v->signal = 0xFFFF * zol_getsigstr(zol);
	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 zoltrix *zol = video_drvdata(file);

	if (zol_setfreq(zol, f->frequency) != 0)
	return -EINVAL;
	return 0;
	}

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

	f->type = V4L2_TUNER_RADIO;
	f->frequency = zol->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);
	case V4L2_CID_AUDIO_VOLUME:
	return v4l2_ctrl_query_fill(qc, 0, 65535, 4096, 65535);
	}
	return -EINVAL;
	}

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

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
	ctrl->value = zol->muted;
	return 0;
	case V4L2_CID_AUDIO_VOLUME:
	ctrl->value = zol->curvol * 4096;
	return 0;
	}
	return -EINVAL;
	}

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

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
	if (ctrl->value)
	zol_mute(zol);
	else {
	zol_unmute(zol);
	zol_setvol(zol, zol->curvol);
	}
	return 0;
	case V4L2_CID_AUDIO_VOLUME:
	zol_setvol(zol, ctrl->value / 4096);
	return 0;
	}
	zol->stereo = 1;
	if (zol_setfreq(zol, zol->curfreq) != 0)
	return -EINVAL;
	#if 0
	/* FIXME: Implement stereo/mono switch on V4L2 */
	if (v->mode & VIDEO_SOUND_STEREO) {
	zol->stereo = 1;
	zol_setfreq(zol, zol->curfreq);
	}
	if (v->mode & VIDEO_SOUND_MONO) {
	zol->stereo = 0;
	zol_setfreq(zol, zol->curfreq);
	}
	#endif
	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 int zoltrix_open(struct file *file)
	{
	return 0;
	}

	static int zoltrix_release(struct file *file)
	{
	return 0;
	}

	static const struct v4l2_file_operations zoltrix_fops =
	{
	.owner = THIS_MODULE,
	.open = zoltrix_open,
	.release = zoltrix_release,
	.ioctl = video_ioctl2,
	};

	static const struct v4l2_ioctl_ops zoltrix_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 int __init zoltrix_init(void)
	{
	struct zoltrix *zol = &zoltrix_card;
	struct v4l2_device *v4l2_dev = &zol->v4l2_dev;
	int res;

	strlcpy(v4l2_dev->name, "zoltrix", sizeof(v4l2_dev->name));
	zol->io = io;
	if (zol->io == -1) {
	v4l2_err(v4l2_dev, "You must set an I/O address with io=0x20c or 0x30c\n");
	return -EINVAL;
	}
	if (zol->io != 0x20c && zol->io != 0x30c) {
	v4l2_err(v4l2_dev, "invalid port, try 0x20c or 0x30c\n");
	return -ENXIO;
	}

	if (!request_region(zol->io, 2, "zoltrix")) {
	v4l2_err(v4l2_dev, "port 0x%x already in use\n", zol->io);
	return -EBUSY;
	}

	res = v4l2_device_register(NULL, v4l2_dev);
	if (res < 0) {
	release_region(zol->io, 2);
	v4l2_err(v4l2_dev, "Could not register v4l2_device\n");
	return res;
	}

	strlcpy(zol->vdev.name, v4l2_dev->name, sizeof(zol->vdev.name));
	zol->vdev.v4l2_dev = v4l2_dev;
	zol->vdev.fops = &zoltrix_fops;
	zol->vdev.ioctl_ops = &zoltrix_ioctl_ops;
	zol->vdev.release = video_device_release_empty;
	video_set_drvdata(&zol->vdev, zol);

	if (video_register_device(&zol->vdev, VFL_TYPE_RADIO, radio_nr) < 0) {
	v4l2_device_unregister(v4l2_dev);
	release_region(zol->io, 2);
	return -EINVAL;
	}
	v4l2_info(v4l2_dev, "Zoltrix Radio Plus card driver.\n");

	mutex_init(&zol->lock);

	/* mute card - prevents noisy bootups */

	/* this ensures that the volume is all the way down */

	outb(0, zol->io);
	outb(0, zol->io);
	msleep(20);
	inb(zol->io + 3);

	zol->curvol = 0;
	zol->stereo = 1;

	return 0;
	}

	static void __exit zoltrix_exit(void)
	{
	struct zoltrix *zol = &zoltrix_card;

	video_unregister_device(&zol->vdev);
	v4l2_device_unregister(&zol->v4l2_dev);
	release_region(zol->io, 2);
	}

	module_init(zoltrix_init);
	module_exit(zoltrix_exit);