sound/i2c/other/tea575x-tuner.c - kernel/msm-5.4 - Gitiles

 /*
  *   ALSA driver for TEA5757/5759 Philips AM/FM radio tuner chips
  *
  *	Copyright (c) 2004 Jaroslav Kysela <perex@perex.cz>
  *
  *
  *   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  *
  */

 #include <asm/io.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
 #include <media/v4l2-device.h>
 #include <media/v4l2-dev.h>
 #include <media/v4l2-fh.h>
 #include <media/v4l2-ioctl.h>
 #include <media/v4l2-event.h>
 #include <sound/tea575x-tuner.h>

 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
 MODULE_DESCRIPTION("Routines for control of TEA5757/5759 Philips AM/FM radio tuner chips");
 MODULE_LICENSE("GPL");

 #define FREQ_LO		 (76U * 16000)
 #define FREQ_HI		(108U * 16000)

 /*
  * definitions
  */

 #define TEA575X_BIT_SEARCH	(1<<24)		/* 1 = search action, 0 = tuned */
 #define TEA575X_BIT_UPDOWN	(1<<23)		/* 0 = search down, 1 = search up */
 #define TEA575X_BIT_MONO	(1<<22)		/* 0 = stereo, 1 = mono */
 #define TEA575X_BIT_BAND_MASK	(3<<20)
 #define TEA575X_BIT_BAND_FM	(0<<20)
 #define TEA575X_BIT_BAND_MW	(1<<20)
 #define TEA575X_BIT_BAND_LW	(1<<21)
 #define TEA575X_BIT_BAND_SW	(1<<22)
 #define TEA575X_BIT_PORT_0	(1<<19)		/* user bit */
 #define TEA575X_BIT_PORT_1	(1<<18)		/* user bit */
 #define TEA575X_BIT_SEARCH_MASK	(3<<16)		/* search level */
 #define TEA575X_BIT_SEARCH_5_28	     (0<<16)	/* FM >5uV, AM >28uV */
 #define TEA575X_BIT_SEARCH_10_40     (1<<16)	/* FM >10uV, AM > 40uV */
 #define TEA575X_BIT_SEARCH_30_63     (2<<16)	/* FM >30uV, AM > 63uV */
 #define TEA575X_BIT_SEARCH_150_1000  (3<<16)	/* FM > 150uV, AM > 1000uV */
 #define TEA575X_BIT_DUMMY	(1<<15)		/* buffer */
 #define TEA575X_BIT_FREQ_MASK	0x7fff

 /*
  * lowlevel part
  */

 static void snd_tea575x_write(struct snd_tea575x *tea, unsigned int val)
 {
 	u16 l;
 	u8 data;

 	tea->ops->set_direction(tea, 1);
 	udelay(16);

 	for (l = 25; l > 0; l--) {
 		data = (val >> 24) & TEA575X_DATA;
 		val <<= 1;			/* shift data */
 		tea->ops->set_pins(tea, data | TEA575X_WREN);
 		udelay(2);
 		tea->ops->set_pins(tea, data | TEA575X_WREN | TEA575X_CLK);
 		udelay(2);
 		tea->ops->set_pins(tea, data | TEA575X_WREN);
 		udelay(2);
 	}

 	if (!tea->mute)
 		tea->ops->set_pins(tea, 0);
 }

 static u32 snd_tea575x_read(struct snd_tea575x *tea)
 {
 	u16 l, rdata;
 	u32 data = 0;

 	tea->ops->set_direction(tea, 0);
 	tea->ops->set_pins(tea, 0);
 	udelay(16);

 	for (l = 24; l--;) {
 		tea->ops->set_pins(tea, TEA575X_CLK);
 		udelay(2);
 		if (!l)
 			tea->tuned = tea->ops->get_pins(tea) & TEA575X_MOST ? 0 : 1;
 		tea->ops->set_pins(tea, 0);
 		udelay(2);
 		data <<= 1;			/* shift data */
 		rdata = tea->ops->get_pins(tea);
 		if (!l)
 			tea->stereo = (rdata & TEA575X_MOST) ?  0 : 1;
 		if (rdata & TEA575X_DATA)
 			data++;
 		udelay(2);
 	}

 	if (tea->mute)
 		tea->ops->set_pins(tea, TEA575X_WREN);

 	return data;
 }

 static u32 snd_tea575x_get_freq(struct snd_tea575x *tea)
 {
 	u32 freq = snd_tea575x_read(tea) & TEA575X_BIT_FREQ_MASK;

 	if (freq == 0)
 		return freq;

 	/* freq *= 12.5 */
 	freq *= 125;
 	freq /= 10;
 	/* crystal fixup */
 	if (tea->tea5759)
 		freq += TEA575X_FMIF;
 	else
 		freq -= TEA575X_FMIF;

 	return clamp(freq * 16, FREQ_LO, FREQ_HI); /* from kHz */
 }

 static void snd_tea575x_set_freq(struct snd_tea575x *tea)
 {
 	u32 freq = tea->freq;

 	freq /= 16;		/* to kHz */
 	/* crystal fixup */
 	if (tea->tea5759)
 		freq -= TEA575X_FMIF;
 	else
 		freq += TEA575X_FMIF;
 	/* freq /= 12.5 */
 	freq *= 10;
 	freq /= 125;

 	tea->val &= ~TEA575X_BIT_FREQ_MASK;
 	tea->val |= freq & TEA575X_BIT_FREQ_MASK;
 	snd_tea575x_write(tea, tea->val);
 }

 /*
  * Linux Video interface
  */

 static int vidioc_querycap(struct file *file, void  *priv,
 					struct v4l2_capability *v)
 {
 	struct snd_tea575x *tea = video_drvdata(file);

 	strlcpy(v->driver, tea->v4l2_dev->name, sizeof(v->driver));
 	strlcpy(v->card, tea->card, sizeof(v->card));
 	strlcat(v->card, tea->tea5759 ? " TEA5759" : " TEA5757", sizeof(v->card));
 	strlcpy(v->bus_info, tea->bus_info, sizeof(v->bus_info));
 	v->device_caps = V4L2_CAP_TUNER | V4L2_CAP_RADIO;
 	if (!tea->cannot_read_data)
 		v->device_caps |= V4L2_CAP_HW_FREQ_SEEK;
 	v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
 	return 0;
 }

 static int vidioc_g_tuner(struct file *file, void *priv,
 					struct v4l2_tuner *v)
 {
 	struct snd_tea575x *tea = video_drvdata(file);

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

 	snd_tea575x_read(tea);

 	strcpy(v->name, "FM");
 	v->type = V4L2_TUNER_RADIO;
 	v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
 	v->rangelow = FREQ_LO;
 	v->rangehigh = FREQ_HI;
 	v->rxsubchans = tea->stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
 	v->audmode = (tea->val & TEA575X_BIT_MONO) ?
 		V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO;
 	v->signal = tea->tuned ? 0xffff : 0;
 	return 0;
 }

 static int vidioc_s_tuner(struct file *file, void *priv,
 					struct v4l2_tuner *v)
 {
 	struct snd_tea575x *tea = video_drvdata(file);

 	if (v->index)
 		return -EINVAL;
 	tea->val &= ~TEA575X_BIT_MONO;
 	if (v->audmode == V4L2_TUNER_MODE_MONO)
 		tea->val |= TEA575X_BIT_MONO;
 	snd_tea575x_write(tea, tea->val);
 	return 0;
 }

 static int vidioc_g_frequency(struct file *file, void *priv,
 					struct v4l2_frequency *f)
 {
 	struct snd_tea575x *tea = video_drvdata(file);

 	if (f->tuner != 0)
 		return -EINVAL;
 	f->type = V4L2_TUNER_RADIO;
 	f->frequency = tea->freq;
 	return 0;
 }

 static int vidioc_s_frequency(struct file *file, void *priv,
 					struct v4l2_frequency *f)
 {
 	struct snd_tea575x *tea = video_drvdata(file);

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

 	tea->val &= ~TEA575X_BIT_SEARCH;
 	tea->freq = clamp(f->frequency, FREQ_LO, FREQ_HI);
 	snd_tea575x_set_freq(tea);
 	return 0;
 }

 static int vidioc_s_hw_freq_seek(struct file *file, void *fh,
 					struct v4l2_hw_freq_seek *a)
 {
 	struct snd_tea575x *tea = video_drvdata(file);
 	unsigned long timeout;
 	int i;

 	if (tea->cannot_read_data)
 		return -ENOTTY;
 	if (a->tuner || a->wrap_around)
 		return -EINVAL;

 	/* clear the frequency, HW will fill it in */
 	tea->val &= ~TEA575X_BIT_FREQ_MASK;
 	tea->val |= TEA575X_BIT_SEARCH;
 	if (a->seek_upward)
 		tea->val |= TEA575X_BIT_UPDOWN;
 	else
 		tea->val &= ~TEA575X_BIT_UPDOWN;
 	snd_tea575x_write(tea, tea->val);
 	timeout = jiffies + msecs_to_jiffies(10000);
 	for (;;) {
 		if (time_after(jiffies, timeout))
 			break;
 		if (schedule_timeout_interruptible(msecs_to_jiffies(10))) {
 			/* some signal arrived, stop search */
 			tea->val &= ~TEA575X_BIT_SEARCH;
 			snd_tea575x_set_freq(tea);
 			return -ERESTARTSYS;
 		}
 		if (!(snd_tea575x_read(tea) & TEA575X_BIT_SEARCH)) {
 			u32 freq;

 			/* Found a frequency, wait until it can be read */
 			for (i = 0; i < 100; i++) {
 				msleep(10);
 				freq = snd_tea575x_get_freq(tea);
 				if (freq) /* available */
 					break;
 			}
 			if (freq == 0) /* shouldn't happen */
 				break;
 			/*
 			 * if we moved by less than 50 kHz, or in the wrong
 			 * direction, continue seeking
 			 */
 			if (abs(tea->freq - freq) < 16 * 50 ||
 					(a->seek_upward && freq < tea->freq) ||
 					(!a->seek_upward && freq > tea->freq)) {
 				snd_tea575x_write(tea, tea->val);
 				continue;
 			}
 			tea->freq = freq;
 			tea->val &= ~TEA575X_BIT_SEARCH;
 			return 0;
 		}
 	}
 	tea->val &= ~TEA575X_BIT_SEARCH;
 	snd_tea575x_set_freq(tea);
 	return -EAGAIN;
 }

 static int tea575x_s_ctrl(struct v4l2_ctrl *ctrl)
 {
 	struct snd_tea575x *tea = container_of(ctrl->handler, struct snd_tea575x, ctrl_handler);

 	switch (ctrl->id) {
 	case V4L2_CID_AUDIO_MUTE:
 		tea->mute = ctrl->val;
 		snd_tea575x_set_freq(tea);
 		return 0;
 	}

 	return -EINVAL;
 }

 static const struct v4l2_file_operations tea575x_fops = {
 	.owner		= THIS_MODULE,
 	.unlocked_ioctl	= video_ioctl2,
 	.open           = v4l2_fh_open,
 	.release        = v4l2_fh_release,
 	.poll           = v4l2_ctrl_poll,
 };

 static const struct v4l2_ioctl_ops tea575x_ioctl_ops = {
 	.vidioc_querycap    = vidioc_querycap,
 	.vidioc_g_tuner     = vidioc_g_tuner,
 	.vidioc_s_tuner     = vidioc_s_tuner,
 	.vidioc_g_frequency = vidioc_g_frequency,
 	.vidioc_s_frequency = vidioc_s_frequency,
 	.vidioc_s_hw_freq_seek = vidioc_s_hw_freq_seek,
 	.vidioc_log_status  = v4l2_ctrl_log_status,
 	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 };

 static const struct video_device tea575x_radio = {
 	.fops           = &tea575x_fops,
 	.ioctl_ops 	= &tea575x_ioctl_ops,
 	.release        = video_device_release_empty,
 };

 static const struct v4l2_ctrl_ops tea575x_ctrl_ops = {
 	.s_ctrl = tea575x_s_ctrl,
 };

 /*
  * initialize all the tea575x chips
  */
 int snd_tea575x_init(struct snd_tea575x *tea)
 {
 	int retval;

 	tea->mute = true;

 	/* Not all devices can or know how to read the data back.
 	   Such devices can set cannot_read_data to true. */
 	if (!tea->cannot_read_data) {
 		snd_tea575x_write(tea, 0x55AA);
 		if (snd_tea575x_read(tea) != 0x55AA)
 			return -ENODEV;
 	}

 	tea->val = TEA575X_BIT_BAND_FM | TEA575X_BIT_SEARCH_5_28;
 	tea->freq = 90500 * 16;		/* 90.5Mhz default */
 	snd_tea575x_set_freq(tea);

 	tea->vd = tea575x_radio;
 	video_set_drvdata(&tea->vd, tea);
 	mutex_init(&tea->mutex);
 	strlcpy(tea->vd.name, tea->v4l2_dev->name, sizeof(tea->vd.name));
 	tea->vd.lock = &tea->mutex;
 	tea->vd.v4l2_dev = tea->v4l2_dev;
 	tea->vd.ctrl_handler = &tea->ctrl_handler;
 	set_bit(V4L2_FL_USE_FH_PRIO, &tea->vd.flags);
 	/* disable hw_freq_seek if we can't use it */
 	if (tea->cannot_read_data)
 		v4l2_dont_use_cmd(&tea->vd, VIDIOC_S_HW_FREQ_SEEK);

 	v4l2_ctrl_handler_init(&tea->ctrl_handler, 1);
 	v4l2_ctrl_new_std(&tea->ctrl_handler, &tea575x_ctrl_ops, V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
 	retval = tea->ctrl_handler.error;
 	if (retval) {
 		v4l2_err(tea->v4l2_dev, "can't initialize controls\n");
 		v4l2_ctrl_handler_free(&tea->ctrl_handler);
 		return retval;
 	}

 	if (tea->ext_init) {
 		retval = tea->ext_init(tea);
 		if (retval) {
 			v4l2_ctrl_handler_free(&tea->ctrl_handler);
 			return retval;
 		}
 	}

 	v4l2_ctrl_handler_setup(&tea->ctrl_handler);

 	retval = video_register_device(&tea->vd, VFL_TYPE_RADIO, tea->radio_nr);
 	if (retval) {
 		v4l2_err(tea->v4l2_dev, "can't register video device!\n");
 		v4l2_ctrl_handler_free(&tea->ctrl_handler);
 		return retval;
 	}

 	return 0;
 }

 void snd_tea575x_exit(struct snd_tea575x *tea)
 {
 	video_unregister_device(&tea->vd);
 	v4l2_ctrl_handler_free(&tea->ctrl_handler);
 }

 static int __init alsa_tea575x_module_init(void)
 {
 	return 0;
 }

 static void __exit alsa_tea575x_module_exit(void)
 {
 }

 module_init(alsa_tea575x_module_init)
 module_exit(alsa_tea575x_module_exit)

 EXPORT_SYMBOL(snd_tea575x_init);
 EXPORT_SYMBOL(snd_tea575x_exit);
	/*
	* ALSA driver for TEA5757/5759 Philips AM/FM radio tuner chips
	*
	* Copyright (c) 2004 Jaroslav Kysela <perex@perex.cz>
	*
	*
	* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*
	*/

	#include <asm/io.h>
	#include <linux/delay.h>
	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/slab.h>
	#include <linux/sched.h>
	#include <media/v4l2-device.h>
	#include <media/v4l2-dev.h>
	#include <media/v4l2-fh.h>
	#include <media/v4l2-ioctl.h>
	#include <media/v4l2-event.h>
	#include <sound/tea575x-tuner.h>

	MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
	MODULE_DESCRIPTION("Routines for control of TEA5757/5759 Philips AM/FM radio tuner chips");
	MODULE_LICENSE("GPL");

	#define FREQ_LO (76U * 16000)
	#define FREQ_HI (108U * 16000)

	/*
	* definitions
	*/

	#define TEA575X_BIT_SEARCH (1<<24) /* 1 = search action, 0 = tuned */
	#define TEA575X_BIT_UPDOWN (1<<23) /* 0 = search down, 1 = search up */
	#define TEA575X_BIT_MONO (1<<22) /* 0 = stereo, 1 = mono */
	#define TEA575X_BIT_BAND_MASK (3<<20)
	#define TEA575X_BIT_BAND_FM (0<<20)
	#define TEA575X_BIT_BAND_MW (1<<20)
	#define TEA575X_BIT_BAND_LW (1<<21)
	#define TEA575X_BIT_BAND_SW (1<<22)
	#define TEA575X_BIT_PORT_0 (1<<19) /* user bit */
	#define TEA575X_BIT_PORT_1 (1<<18) /* user bit */
	#define TEA575X_BIT_SEARCH_MASK (3<<16) /* search level */
	#define TEA575X_BIT_SEARCH_5_28 (0<<16) /* FM >5uV, AM >28uV */
	#define TEA575X_BIT_SEARCH_10_40 (1<<16) /* FM >10uV, AM > 40uV */
	#define TEA575X_BIT_SEARCH_30_63 (2<<16) /* FM >30uV, AM > 63uV */
	#define TEA575X_BIT_SEARCH_150_1000 (3<<16) /* FM > 150uV, AM > 1000uV */
	#define TEA575X_BIT_DUMMY (1<<15) /* buffer */
	#define TEA575X_BIT_FREQ_MASK 0x7fff

	/*
	* lowlevel part
	*/

	static void snd_tea575x_write(struct snd_tea575x *tea, unsigned int val)
	{
	u16 l;
	u8 data;

	tea->ops->set_direction(tea, 1);
	udelay(16);

	for (l = 25; l > 0; l--) {
	data = (val >> 24) & TEA575X_DATA;
	val <<= 1; /* shift data */
	tea->ops->set_pins(tea, data \| TEA575X_WREN);
	udelay(2);
	tea->ops->set_pins(tea, data \| TEA575X_WREN \| TEA575X_CLK);
	udelay(2);
	tea->ops->set_pins(tea, data \| TEA575X_WREN);
	udelay(2);
	}

	if (!tea->mute)
	tea->ops->set_pins(tea, 0);
	}

	static u32 snd_tea575x_read(struct snd_tea575x *tea)
	{
	u16 l, rdata;
	u32 data = 0;

	tea->ops->set_direction(tea, 0);
	tea->ops->set_pins(tea, 0);
	udelay(16);

	for (l = 24; l--;) {
	tea->ops->set_pins(tea, TEA575X_CLK);
	udelay(2);
	if (!l)
	tea->tuned = tea->ops->get_pins(tea) & TEA575X_MOST ? 0 : 1;
	tea->ops->set_pins(tea, 0);
	udelay(2);
	data <<= 1; /* shift data */
	rdata = tea->ops->get_pins(tea);
	if (!l)
	tea->stereo = (rdata & TEA575X_MOST) ? 0 : 1;
	if (rdata & TEA575X_DATA)
	data++;
	udelay(2);
	}

	if (tea->mute)
	tea->ops->set_pins(tea, TEA575X_WREN);

	return data;
	}

	static u32 snd_tea575x_get_freq(struct snd_tea575x *tea)
	{
	u32 freq = snd_tea575x_read(tea) & TEA575X_BIT_FREQ_MASK;

	if (freq == 0)
	return freq;

	/* freq = 12.5 /
	freq *= 125;
	freq /= 10;
	/* crystal fixup */
	if (tea->tea5759)
	freq += TEA575X_FMIF;
	else
	freq -= TEA575X_FMIF;

	return clamp(freq * 16, FREQ_LO, FREQ_HI); /* from kHz */
	}

	static void snd_tea575x_set_freq(struct snd_tea575x *tea)
	{
	u32 freq = tea->freq;

	freq /= 16; /* to kHz */
	/* crystal fixup */
	if (tea->tea5759)
	freq -= TEA575X_FMIF;
	else
	freq += TEA575X_FMIF;
	/* freq /= 12.5 */
	freq *= 10;
	freq /= 125;

	tea->val &= ~TEA575X_BIT_FREQ_MASK;
	tea->val \|= freq & TEA575X_BIT_FREQ_MASK;
	snd_tea575x_write(tea, tea->val);
	}

	/*
	* Linux Video interface
	*/

	static int vidioc_querycap(struct file file, void priv,
	struct v4l2_capability *v)
	{
	struct snd_tea575x *tea = video_drvdata(file);

	strlcpy(v->driver, tea->v4l2_dev->name, sizeof(v->driver));
	strlcpy(v->card, tea->card, sizeof(v->card));
	strlcat(v->card, tea->tea5759 ? " TEA5759" : " TEA5757", sizeof(v->card));
	strlcpy(v->bus_info, tea->bus_info, sizeof(v->bus_info));
	v->device_caps = V4L2_CAP_TUNER \| V4L2_CAP_RADIO;
	if (!tea->cannot_read_data)
	v->device_caps \|= V4L2_CAP_HW_FREQ_SEEK;
	v->capabilities = v->device_caps \| V4L2_CAP_DEVICE_CAPS;
	return 0;
	}

	static int vidioc_g_tuner(struct file file, void priv,
	struct v4l2_tuner *v)
	{
	struct snd_tea575x *tea = video_drvdata(file);

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

	snd_tea575x_read(tea);

	strcpy(v->name, "FM");
	v->type = V4L2_TUNER_RADIO;
	v->capability = V4L2_TUNER_CAP_LOW \| V4L2_TUNER_CAP_STEREO;
	v->rangelow = FREQ_LO;
	v->rangehigh = FREQ_HI;
	v->rxsubchans = tea->stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
	v->audmode = (tea->val & TEA575X_BIT_MONO) ?
	V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO;
	v->signal = tea->tuned ? 0xffff : 0;
	return 0;
	}

	static int vidioc_s_tuner(struct file file, void priv,
	struct v4l2_tuner *v)
	{
	struct snd_tea575x *tea = video_drvdata(file);

	if (v->index)
	return -EINVAL;
	tea->val &= ~TEA575X_BIT_MONO;
	if (v->audmode == V4L2_TUNER_MODE_MONO)
	tea->val \|= TEA575X_BIT_MONO;
	snd_tea575x_write(tea, tea->val);
	return 0;
	}

	static int vidioc_g_frequency(struct file file, void priv,
	struct v4l2_frequency *f)
	{
	struct snd_tea575x *tea = video_drvdata(file);

	if (f->tuner != 0)
	return -EINVAL;
	f->type = V4L2_TUNER_RADIO;
	f->frequency = tea->freq;
	return 0;
	}

	static int vidioc_s_frequency(struct file file, void priv,
	struct v4l2_frequency *f)
	{
	struct snd_tea575x *tea = video_drvdata(file);

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

	tea->val &= ~TEA575X_BIT_SEARCH;
	tea->freq = clamp(f->frequency, FREQ_LO, FREQ_HI);
	snd_tea575x_set_freq(tea);
	return 0;
	}

	static int vidioc_s_hw_freq_seek(struct file file, void fh,
	struct v4l2_hw_freq_seek *a)
	{
	struct snd_tea575x *tea = video_drvdata(file);
	unsigned long timeout;
	int i;

	if (tea->cannot_read_data)
	return -ENOTTY;
	if (a->tuner \|\| a->wrap_around)
	return -EINVAL;

	/* clear the frequency, HW will fill it in */
	tea->val &= ~TEA575X_BIT_FREQ_MASK;
	tea->val \|= TEA575X_BIT_SEARCH;
	if (a->seek_upward)
	tea->val \|= TEA575X_BIT_UPDOWN;
	else
	tea->val &= ~TEA575X_BIT_UPDOWN;
	snd_tea575x_write(tea, tea->val);
	timeout = jiffies + msecs_to_jiffies(10000);
	for (;;) {
	if (time_after(jiffies, timeout))
	break;
	if (schedule_timeout_interruptible(msecs_to_jiffies(10))) {
	/* some signal arrived, stop search */
	tea->val &= ~TEA575X_BIT_SEARCH;
	snd_tea575x_set_freq(tea);
	return -ERESTARTSYS;
	}
	if (!(snd_tea575x_read(tea) & TEA575X_BIT_SEARCH)) {
	u32 freq;

	/* Found a frequency, wait until it can be read */
	for (i = 0; i < 100; i++) {
	msleep(10);
	freq = snd_tea575x_get_freq(tea);
	if (freq) /* available */
	break;
	}
	if (freq == 0) /* shouldn't happen */
	break;
	/*
	* if we moved by less than 50 kHz, or in the wrong
	* direction, continue seeking
	*/
	if (abs(tea->freq - freq) < 16 * 50 \|\|
	(a->seek_upward && freq < tea->freq) \|\|
	(!a->seek_upward && freq > tea->freq)) {
	snd_tea575x_write(tea, tea->val);
	continue;
	}
	tea->freq = freq;
	tea->val &= ~TEA575X_BIT_SEARCH;
	return 0;
	}
	}
	tea->val &= ~TEA575X_BIT_SEARCH;
	snd_tea575x_set_freq(tea);
	return -EAGAIN;
	}

	static int tea575x_s_ctrl(struct v4l2_ctrl *ctrl)
	{
	struct snd_tea575x *tea = container_of(ctrl->handler, struct snd_tea575x, ctrl_handler);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
	tea->mute = ctrl->val;
	snd_tea575x_set_freq(tea);
	return 0;
	}

	return -EINVAL;
	}

	static const struct v4l2_file_operations tea575x_fops = {
	.owner = THIS_MODULE,
	.unlocked_ioctl = video_ioctl2,
	.open = v4l2_fh_open,
	.release = v4l2_fh_release,
	.poll = v4l2_ctrl_poll,
	};

	static const struct v4l2_ioctl_ops tea575x_ioctl_ops = {
	.vidioc_querycap = vidioc_querycap,
	.vidioc_g_tuner = vidioc_g_tuner,
	.vidioc_s_tuner = vidioc_s_tuner,
	.vidioc_g_frequency = vidioc_g_frequency,
	.vidioc_s_frequency = vidioc_s_frequency,
	.vidioc_s_hw_freq_seek = vidioc_s_hw_freq_seek,
	.vidioc_log_status = v4l2_ctrl_log_status,
	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
	};

	static const struct video_device tea575x_radio = {
	.fops = &tea575x_fops,
	.ioctl_ops = &tea575x_ioctl_ops,
	.release = video_device_release_empty,
	};

	static const struct v4l2_ctrl_ops tea575x_ctrl_ops = {
	.s_ctrl = tea575x_s_ctrl,
	};

	/*
	* initialize all the tea575x chips
	*/
	int snd_tea575x_init(struct snd_tea575x *tea)
	{
	int retval;

	tea->mute = true;

	/* Not all devices can or know how to read the data back.
	Such devices can set cannot_read_data to true. */
	if (!tea->cannot_read_data) {
	snd_tea575x_write(tea, 0x55AA);
	if (snd_tea575x_read(tea) != 0x55AA)
	return -ENODEV;
	}

	tea->val = TEA575X_BIT_BAND_FM \| TEA575X_BIT_SEARCH_5_28;
	tea->freq = 90500 * 16; /* 90.5Mhz default */
	snd_tea575x_set_freq(tea);

	tea->vd = tea575x_radio;
	video_set_drvdata(&tea->vd, tea);
	mutex_init(&tea->mutex);
	strlcpy(tea->vd.name, tea->v4l2_dev->name, sizeof(tea->vd.name));
	tea->vd.lock = &tea->mutex;
	tea->vd.v4l2_dev = tea->v4l2_dev;
	tea->vd.ctrl_handler = &tea->ctrl_handler;
	set_bit(V4L2_FL_USE_FH_PRIO, &tea->vd.flags);
	/* disable hw_freq_seek if we can't use it */
	if (tea->cannot_read_data)
	v4l2_dont_use_cmd(&tea->vd, VIDIOC_S_HW_FREQ_SEEK);

	v4l2_ctrl_handler_init(&tea->ctrl_handler, 1);
	v4l2_ctrl_new_std(&tea->ctrl_handler, &tea575x_ctrl_ops, V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
	retval = tea->ctrl_handler.error;
	if (retval) {
	v4l2_err(tea->v4l2_dev, "can't initialize controls\n");
	v4l2_ctrl_handler_free(&tea->ctrl_handler);
	return retval;
	}

	if (tea->ext_init) {
	retval = tea->ext_init(tea);
	if (retval) {
	v4l2_ctrl_handler_free(&tea->ctrl_handler);
	return retval;
	}
	}

	v4l2_ctrl_handler_setup(&tea->ctrl_handler);

	retval = video_register_device(&tea->vd, VFL_TYPE_RADIO, tea->radio_nr);
	if (retval) {
	v4l2_err(tea->v4l2_dev, "can't register video device!\n");
	v4l2_ctrl_handler_free(&tea->ctrl_handler);
	return retval;
	}

	return 0;
	}

	void snd_tea575x_exit(struct snd_tea575x *tea)
	{
	video_unregister_device(&tea->vd);
	v4l2_ctrl_handler_free(&tea->ctrl_handler);
	}

	static int __init alsa_tea575x_module_init(void)
	{
	return 0;
	}

	static void __exit alsa_tea575x_module_exit(void)
	{
	}

	module_init(alsa_tea575x_module_init)
	module_exit(alsa_tea575x_module_exit)

	EXPORT_SYMBOL(snd_tea575x_init);
	EXPORT_SYMBOL(snd_tea575x_exit);