drivers/media/video/tda7432.c - kernel/msm-4.9 - Gitiles

 /*
  * For the STS-Thompson TDA7432 audio processor chip
  *
  * Handles audio functions: volume, balance, tone, loudness
  * This driver will not complain if used with any
  * other i2c device with the same address.
  *
  * Muting and tone control by Jonathan Isom <jisom@ematic.com>
  *
  * Copyright (c) 2000 Eric Sandeen <eric_sandeen@bigfoot.com>
  * Copyright (c) 2006 Mauro Carvalho Chehab <mchehab@infradead.org>
  * This code is placed under the terms of the GNU General Public License
  * Based on tda9855.c by Steve VanDeBogart (vandebo@uclink.berkeley.edu)
  * Which was based on tda8425.c by Greg Alexander (c) 1998
  *
  * OPTIONS:
  * debug    - set to 1 if you'd like to see debug messages
  *            set to 2 if you'd like to be inundated with debug messages
  *
  * loudness - set between 0 and 15 for varying degrees of loudness effect
  *
  * maxvol   - set maximium volume to +20db (1), default is 0db(0)
  *
  *
  *  Revision: 0.7 - maxvol module parm to set maximium volume 0db or +20db
  *  				store if muted so we can return it
  *  				change balance only if flaged to
  *  Revision: 0.6 - added tone controls
  *  Revision: 0.5 - Fixed odd balance problem
  *  Revision: 0.4 - added muting
  *  Revision: 0.3 - Fixed silly reversed volume controls.  :)
  *  Revision: 0.2 - Cleaned up #defines
  *			fixed volume control
  *          Added I2C_DRIVERID_TDA7432
  *			added loudness insmod control
  *  Revision: 0.1 - initial version
  */

 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/timer.h>
 #include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
 #include <linux/videodev2.h>
 #include <linux/i2c.h>

 #include <media/v4l2-device.h>
 #include <media/v4l2-ioctl.h>
 #include <media/i2c-addr.h>
 #include <media/v4l2-i2c-drv.h>

 #ifndef VIDEO_AUDIO_BALANCE
 # define VIDEO_AUDIO_BALANCE 32
 #endif

 MODULE_AUTHOR("Eric Sandeen <eric_sandeen@bigfoot.com>");
 MODULE_DESCRIPTION("bttv driver for the tda7432 audio processor chip");
 MODULE_LICENSE("GPL");

 static int maxvol;
 static int loudness; /* disable loudness by default */
 static int debug;	 /* insmod parameter */
 module_param(debug, int, S_IRUGO | S_IWUSR);
 module_param(loudness, int, S_IRUGO);
 MODULE_PARM_DESC(maxvol,"Set maximium volume to +20db (0), default is 0db(1)");
 module_param(maxvol, int, S_IRUGO | S_IWUSR);


 /* Structure of address and subaddresses for the tda7432 */

 struct tda7432 {
 	struct v4l2_subdev sd;
 	int addr;
 	int input;
 	int volume;
 	int muted;
 	int bass, treble;
 	int lf, lr, rf, rr;
 	int loud;
 };

 static inline struct tda7432 *to_state(struct v4l2_subdev *sd)
 {
 	return container_of(sd, struct tda7432, sd);
 }

 /* The TDA7432 is made by STS-Thompson
  * http://www.st.com
  * http://us.st.com/stonline/books/pdf/docs/4056.pdf
  *
  * TDA7432: I2C-bus controlled basic audio processor
  *
  * The TDA7432 controls basic audio functions like volume, balance,
  * and tone control (including loudness).  It also has four channel
  * output (for front and rear).  Since most vidcap cards probably
  * don't have 4 channel output, this driver will set front & rear
  * together (no independent control).
  */

 		/* Subaddresses for TDA7432 */

 #define TDA7432_IN	0x00 /* Input select                 */
 #define TDA7432_VL	0x01 /* Volume                       */
 #define TDA7432_TN	0x02 /* Bass, Treble (Tone)          */
 #define TDA7432_LF	0x03 /* Attenuation LF (Left Front)  */
 #define TDA7432_LR	0x04 /* Attenuation LR (Left Rear)   */
 #define TDA7432_RF	0x05 /* Attenuation RF (Right Front) */
 #define TDA7432_RR	0x06 /* Attenuation RR (Right Rear)  */
 #define TDA7432_LD	0x07 /* Loudness                     */


 		/* Masks for bits in TDA7432 subaddresses */

 /* Many of these not used - just for documentation */

 /* Subaddress 0x00 - Input selection and bass control */

 /* Bits 0,1,2 control input:
  * 0x00 - Stereo input
  * 0x02 - Mono input
  * 0x03 - Mute  (Using Attenuators Plays better with modules)
  * Mono probably isn't used - I'm guessing only the stereo
  * input is connected on most cards, so we'll set it to stereo.
  *
  * Bit 3 controls bass cut: 0/1 is non-symmetric/symmetric bass cut
  * Bit 4 controls bass range: 0/1 is extended/standard bass range
  *
  * Highest 3 bits not used
  */

 #define TDA7432_STEREO_IN	0
 #define TDA7432_MONO_IN		2	/* Probably won't be used */
 #define TDA7432_BASS_SYM	1 << 3
 #define TDA7432_BASS_NORM	1 << 4

 /* Subaddress 0x01 - Volume */

 /* Lower 7 bits control volume from -79dB to +32dB in 1dB steps
  * Recommended maximum is +20 dB
  *
  * +32dB: 0x00
  * +20dB: 0x0c
  *   0dB: 0x20
  * -79dB: 0x6f
  *
  * MSB (bit 7) controls loudness: 1/0 is loudness on/off
  */

 #define	TDA7432_VOL_0DB		0x20
 #define TDA7432_LD_ON		1 << 7


 /* Subaddress 0x02 - Tone control */

 /* Bits 0,1,2 control absolute treble gain from 0dB to 14dB
  * 0x0 is 14dB, 0x7 is 0dB
  *
  * Bit 3 controls treble attenuation/gain (sign)
  * 1 = gain (+)
  * 0 = attenuation (-)
  *
  * Bits 4,5,6 control absolute bass gain from 0dB to 14dB
  * (This is only true for normal base range, set in 0x00)
  * 0x0 << 4 is 14dB, 0x7 is 0dB
  *
  * Bit 7 controls bass attenuation/gain (sign)
  * 1 << 7 = gain (+)
  * 0 << 7 = attenuation (-)
  *
  * Example:
  * 1 1 0 1 0 1 0 1 is +4dB bass, -4dB treble
  */

 #define TDA7432_TREBLE_0DB		0xf
 #define TDA7432_TREBLE			7
 #define TDA7432_TREBLE_GAIN		1 << 3
 #define TDA7432_BASS_0DB		0xf
 #define TDA7432_BASS			7 << 4
 #define TDA7432_BASS_GAIN		1 << 7


 /* Subaddress 0x03 - Left  Front attenuation */
 /* Subaddress 0x04 - Left  Rear  attenuation */
 /* Subaddress 0x05 - Right Front attenuation */
 /* Subaddress 0x06 - Right Rear  attenuation */

 /* Bits 0,1,2,3,4 control attenuation from 0dB to -37.5dB
  * in 1.5dB steps.
  *
  * 0x00 is     0dB
  * 0x1f is -37.5dB
  *
  * Bit 5 mutes that channel when set (1 = mute, 0 = unmute)
  * We'll use the mute on the input, though (above)
  * Bits 6,7 unused
  */

 #define TDA7432_ATTEN_0DB	0x00
 #define TDA7432_MUTE        0x1 << 5


 /* Subaddress 0x07 - Loudness Control */

 /* Bits 0,1,2,3 control loudness from 0dB to -15dB in 1dB steps
  * when bit 4 is NOT set
  *
  * 0x0 is   0dB
  * 0xf is -15dB
  *
  * If bit 4 is set, then there is a flat attenuation according to
  * the lower 4 bits, as above.
  *
  * Bits 5,6,7 unused
  */


 /* Begin code */

 static int tda7432_write(struct v4l2_subdev *sd, int subaddr, int val)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(sd);
 	unsigned char buffer[2];

 	v4l2_dbg(2, debug, sd, "In tda7432_write\n");
 	v4l2_dbg(1, debug, sd, "Writing %d 0x%x\n", subaddr, val);
 	buffer[0] = subaddr;
 	buffer[1] = val;
 	if (2 != i2c_master_send(client, buffer, 2)) {
 		v4l2_err(sd, "I/O error, trying (write %d 0x%x)\n",
 		       subaddr, val);
 		return -1;
 	}
 	return 0;
 }

 static int tda7432_set(struct v4l2_subdev *sd)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(sd);
 	struct tda7432 *t = to_state(sd);
 	unsigned char buf[16];

 	v4l2_dbg(1, debug, sd,
 		"tda7432: 7432_set(0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x)\n",
 		t->input, t->volume, t->bass, t->treble, t->lf, t->lr,
 		t->rf, t->rr, t->loud);
 	buf[0]  = TDA7432_IN;
 	buf[1]  = t->input;
 	buf[2]  = t->volume;
 	buf[3]  = t->bass;
 	buf[4]	= t->treble;
 	buf[5]  = t->lf;
 	buf[6]  = t->lr;
 	buf[7]  = t->rf;
 	buf[8]  = t->rr;
 	buf[9]  = t->loud;
 	if (10 != i2c_master_send(client, buf, 10)) {
 		v4l2_err(sd, "I/O error, trying tda7432_set\n");
 		return -1;
 	}

 	return 0;
 }

 static void do_tda7432_init(struct v4l2_subdev *sd)
 {
 	struct tda7432 *t = to_state(sd);

 	v4l2_dbg(2, debug, sd, "In tda7432_init\n");

 	t->input  = TDA7432_STEREO_IN |  /* Main (stereo) input   */
 		    TDA7432_BASS_SYM  |  /* Symmetric bass cut    */
 		    TDA7432_BASS_NORM;   /* Normal bass range     */
 	t->volume =  0x3b ;				 /* -27dB Volume            */
 	if (loudness)			 /* Turn loudness on?     */
 		t->volume |= TDA7432_LD_ON;
 	t->muted    = 1;
 	t->treble   = TDA7432_TREBLE_0DB; /* 0dB Treble            */
 	t->bass		= TDA7432_BASS_0DB; 	 /* 0dB Bass              */
 	t->lf     = TDA7432_ATTEN_0DB;	 /* 0dB attenuation       */
 	t->lr     = TDA7432_ATTEN_0DB;	 /* 0dB attenuation       */
 	t->rf     = TDA7432_ATTEN_0DB;	 /* 0dB attenuation       */
 	t->rr     = TDA7432_ATTEN_0DB;	 /* 0dB attenuation       */
 	t->loud   = loudness;		 /* insmod parameter      */

 	tda7432_set(sd);
 }

 static int tda7432_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 {
 	struct tda7432 *t = to_state(sd);

 	switch (ctrl->id) {
 	case V4L2_CID_AUDIO_MUTE:
 		ctrl->value=t->muted;
 		return 0;
 	case V4L2_CID_AUDIO_VOLUME:
 		if (!maxvol){  /* max +20db */
 			ctrl->value = ( 0x6f - (t->volume & 0x7F) ) * 630;
 		} else {       /* max 0db   */
 			ctrl->value = ( 0x6f - (t->volume & 0x7F) ) * 829;
 		}
 		return 0;
 	case V4L2_CID_AUDIO_BALANCE:
 	{
 		if ( (t->lf) < (t->rf) )
 			/* right is attenuated, balance shifted left */
 			ctrl->value = (32768 - 1057*(t->rf));
 		else
 			/* left is attenuated, balance shifted right */
 			ctrl->value = (32768 + 1057*(t->lf));
 		return 0;
 	}
 	case V4L2_CID_AUDIO_BASS:
 	{
 		/* Bass/treble 4 bits each */
 		int bass=t->bass;
 		if(bass >= 0x8)
 			bass = ~(bass - 0x8) & 0xf;
 		ctrl->value = (bass << 12)+(bass << 8)+(bass << 4)+(bass);
 		return 0;
 	}
 	case V4L2_CID_AUDIO_TREBLE:
 	{
 		int treble=t->treble;
 		if(treble >= 0x8)
 			treble = ~(treble - 0x8) & 0xf;
 		ctrl->value = (treble << 12)+(treble << 8)+(treble << 4)+(treble);
 		return 0;
 	}
 	}
 	return -EINVAL;
 }

 static int tda7432_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 {
 	struct tda7432 *t = to_state(sd);

 	switch (ctrl->id) {
 	case V4L2_CID_AUDIO_MUTE:
 		t->muted=ctrl->value;
 		break;
 	case V4L2_CID_AUDIO_VOLUME:
 		if(!maxvol){ /* max +20db */
 			t->volume = 0x6f - ((ctrl->value)/630);
 		} else {    /* max 0db   */
 			t->volume = 0x6f - ((ctrl->value)/829);
 		}
 		if (loudness)		/* Turn on the loudness bit */
 			t->volume |= TDA7432_LD_ON;

 		tda7432_write(sd, TDA7432_VL, t->volume);
 		return 0;
 	case V4L2_CID_AUDIO_BALANCE:
 		if (ctrl->value < 32768) {
 			/* shifted to left, attenuate right */
 			t->rr = (32768 - ctrl->value)/1057;
 			t->rf = t->rr;
 			t->lr = TDA7432_ATTEN_0DB;
 			t->lf = TDA7432_ATTEN_0DB;
 		} else if(ctrl->value > 32769) {
 			/* shifted to right, attenuate left */
 			t->lf = (ctrl->value - 32768)/1057;
 			t->lr = t->lf;
 			t->rr = TDA7432_ATTEN_0DB;
 			t->rf = TDA7432_ATTEN_0DB;
 		} else {
 			/* centered */
 			t->rr = TDA7432_ATTEN_0DB;
 			t->rf = TDA7432_ATTEN_0DB;
 			t->lf = TDA7432_ATTEN_0DB;
 			t->lr = TDA7432_ATTEN_0DB;
 		}
 		break;
 	case V4L2_CID_AUDIO_BASS:
 		t->bass = ctrl->value >> 12;
 		if(t->bass>= 0x8)
 				t->bass = (~t->bass & 0xf) + 0x8 ;

 		tda7432_write(sd, TDA7432_TN, 0x10 | (t->bass << 4) | t->treble);
 		return 0;
 	case V4L2_CID_AUDIO_TREBLE:
 		t->treble= ctrl->value >> 12;
 		if(t->treble>= 0x8)
 				t->treble = (~t->treble & 0xf) + 0x8 ;

 		tda7432_write(sd, TDA7432_TN, 0x10 | (t->bass << 4) | t->treble);
 		return 0;
 	default:
 		return -EINVAL;
 	}

 	/* Used for both mute and balance changes */
 	if (t->muted)
 	{
 		/* Mute & update balance*/
 		tda7432_write(sd, TDA7432_LF, t->lf | TDA7432_MUTE);
 		tda7432_write(sd, TDA7432_LR, t->lr | TDA7432_MUTE);
 		tda7432_write(sd, TDA7432_RF, t->rf | TDA7432_MUTE);
 		tda7432_write(sd, TDA7432_RR, t->rr | TDA7432_MUTE);
 	} else {
 		tda7432_write(sd, TDA7432_LF, t->lf);
 		tda7432_write(sd, TDA7432_LR, t->lr);
 		tda7432_write(sd, TDA7432_RF, t->rf);
 		tda7432_write(sd, TDA7432_RR, t->rr);
 	}
 	return 0;
 }

 static int tda7432_queryctrl(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc)
 {
 	switch (qc->id) {
 	case V4L2_CID_AUDIO_VOLUME:
 		return v4l2_ctrl_query_fill(qc, 0, 65535, 65535 / 100, 58880);
 	case V4L2_CID_AUDIO_MUTE:
 		return v4l2_ctrl_query_fill(qc, 0, 1, 1, 0);
 	case V4L2_CID_AUDIO_BALANCE:
 	case V4L2_CID_AUDIO_BASS:
 	case V4L2_CID_AUDIO_TREBLE:
 		return v4l2_ctrl_query_fill(qc, 0, 65535, 65535 / 100, 32768);
 	}
 	return -EINVAL;
 }

 /* ----------------------------------------------------------------------- */

 static const struct v4l2_subdev_core_ops tda7432_core_ops = {
 	.queryctrl = tda7432_queryctrl,
 	.g_ctrl = tda7432_g_ctrl,
 	.s_ctrl = tda7432_s_ctrl,
 };

 static const struct v4l2_subdev_ops tda7432_ops = {
 	.core = &tda7432_core_ops,
 };

 /* ----------------------------------------------------------------------- */

 /* *********************** *
  * i2c interface functions *
  * *********************** */

 static int tda7432_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
 	struct tda7432 *t;
 	struct v4l2_subdev *sd;

 	v4l_info(client, "chip found @ 0x%02x (%s)\n",
 			client->addr << 1, client->adapter->name);

 	t = kzalloc(sizeof(*t), GFP_KERNEL);
 	if (!t)
 		return -ENOMEM;
 	sd = &t->sd;
 	v4l2_i2c_subdev_init(sd, client, &tda7432_ops);
 	if (loudness < 0 || loudness > 15) {
 		v4l2_warn(sd, "loudness parameter must be between 0 and 15\n");
 		if (loudness < 0)
 			loudness = 0;
 		if (loudness > 15)
 			loudness = 15;
 	}

 	do_tda7432_init(sd);
 	return 0;
 }

 static int tda7432_remove(struct i2c_client *client)
 {
 	struct v4l2_subdev *sd = i2c_get_clientdata(client);

 	do_tda7432_init(sd);
 	v4l2_device_unregister_subdev(sd);
 	kfree(to_state(sd));
 	return 0;
 }

 static const struct i2c_device_id tda7432_id[] = {
 	{ "tda7432", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, tda7432_id);

 static struct v4l2_i2c_driver_data v4l2_i2c_data = {
 	.name = "tda7432",
 	.probe = tda7432_probe,
 	.remove = tda7432_remove,
 	.id_table = tda7432_id,
 };
	/*
	* For the STS-Thompson TDA7432 audio processor chip
	*
	* Handles audio functions: volume, balance, tone, loudness
	* This driver will not complain if used with any
	* other i2c device with the same address.
	*
	* Muting and tone control by Jonathan Isom <jisom@ematic.com>
	*
	* Copyright (c) 2000 Eric Sandeen <eric_sandeen@bigfoot.com>
	* Copyright (c) 2006 Mauro Carvalho Chehab <mchehab@infradead.org>
	* This code is placed under the terms of the GNU General Public License
	* Based on tda9855.c by Steve VanDeBogart (vandebo@uclink.berkeley.edu)
	* Which was based on tda8425.c by Greg Alexander (c) 1998
	*
	* OPTIONS:
	* debug - set to 1 if you'd like to see debug messages
	* set to 2 if you'd like to be inundated with debug messages
	*
	* loudness - set between 0 and 15 for varying degrees of loudness effect
	*
	* maxvol - set maximium volume to +20db (1), default is 0db(0)
	*
	*
	* Revision: 0.7 - maxvol module parm to set maximium volume 0db or +20db
	* store if muted so we can return it
	* change balance only if flaged to
	* Revision: 0.6 - added tone controls
	* Revision: 0.5 - Fixed odd balance problem
	* Revision: 0.4 - added muting
	* Revision: 0.3 - Fixed silly reversed volume controls. :)
	* Revision: 0.2 - Cleaned up #defines
	* fixed volume control
	* Added I2C_DRIVERID_TDA7432
	* added loudness insmod control
	* Revision: 0.1 - initial version
	*/

	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/string.h>
	#include <linux/timer.h>
	#include <linux/delay.h>
	#include <linux/errno.h>
	#include <linux/slab.h>
	#include <linux/videodev2.h>
	#include <linux/i2c.h>

	#include <media/v4l2-device.h>
	#include <media/v4l2-ioctl.h>
	#include <media/i2c-addr.h>
	#include <media/v4l2-i2c-drv.h>

	#ifndef VIDEO_AUDIO_BALANCE
	# define VIDEO_AUDIO_BALANCE 32
	#endif

	MODULE_AUTHOR("Eric Sandeen <eric_sandeen@bigfoot.com>");
	MODULE_DESCRIPTION("bttv driver for the tda7432 audio processor chip");
	MODULE_LICENSE("GPL");

	static int maxvol;
	static int loudness; /* disable loudness by default */
	static int debug; /* insmod parameter */
	module_param(debug, int, S_IRUGO \| S_IWUSR);
	module_param(loudness, int, S_IRUGO);
	MODULE_PARM_DESC(maxvol,"Set maximium volume to +20db (0), default is 0db(1)");
	module_param(maxvol, int, S_IRUGO \| S_IWUSR);



	/* Structure of address and subaddresses for the tda7432 */

	struct tda7432 {
	struct v4l2_subdev sd;
	int addr;
	int input;
	int volume;
	int muted;
	int bass, treble;
	int lf, lr, rf, rr;
	int loud;
	};

	static inline struct tda7432 to_state(struct v4l2_subdev sd)
	{
	return container_of(sd, struct tda7432, sd);
	}

	/* The TDA7432 is made by STS-Thompson
	* http://www.st.com
	* http://us.st.com/stonline/books/pdf/docs/4056.pdf
	*
	* TDA7432: I2C-bus controlled basic audio processor
	*
	* The TDA7432 controls basic audio functions like volume, balance,
	* and tone control (including loudness). It also has four channel
	* output (for front and rear). Since most vidcap cards probably
	* don't have 4 channel output, this driver will set front & rear
	* together (no independent control).
	*/

	/* Subaddresses for TDA7432 */

	#define TDA7432_IN 0x00 /* Input select */
	#define TDA7432_VL 0x01 /* Volume */
	#define TDA7432_TN 0x02 /* Bass, Treble (Tone) */
	#define TDA7432_LF 0x03 /* Attenuation LF (Left Front) */
	#define TDA7432_LR 0x04 /* Attenuation LR (Left Rear) */
	#define TDA7432_RF 0x05 /* Attenuation RF (Right Front) */
	#define TDA7432_RR 0x06 /* Attenuation RR (Right Rear) */
	#define TDA7432_LD 0x07 /* Loudness */


	/* Masks for bits in TDA7432 subaddresses */

	/* Many of these not used - just for documentation */

	/* Subaddress 0x00 - Input selection and bass control */

	/* Bits 0,1,2 control input:
	* 0x00 - Stereo input
	* 0x02 - Mono input
	* 0x03 - Mute (Using Attenuators Plays better with modules)
	* Mono probably isn't used - I'm guessing only the stereo
	* input is connected on most cards, so we'll set it to stereo.
	*
	* Bit 3 controls bass cut: 0/1 is non-symmetric/symmetric bass cut
	* Bit 4 controls bass range: 0/1 is extended/standard bass range
	*
	* Highest 3 bits not used
	*/

	#define TDA7432_STEREO_IN 0
	#define TDA7432_MONO_IN 2 /* Probably won't be used */
	#define TDA7432_BASS_SYM 1 << 3
	#define TDA7432_BASS_NORM 1 << 4

	/* Subaddress 0x01 - Volume */

	/* Lower 7 bits control volume from -79dB to +32dB in 1dB steps
	* Recommended maximum is +20 dB
	*
	* +32dB: 0x00
	* +20dB: 0x0c
	* 0dB: 0x20
	* -79dB: 0x6f
	*
	* MSB (bit 7) controls loudness: 1/0 is loudness on/off
	*/

	#define TDA7432_VOL_0DB 0x20
	#define TDA7432_LD_ON 1 << 7


	/* Subaddress 0x02 - Tone control */

	/* Bits 0,1,2 control absolute treble gain from 0dB to 14dB
	* 0x0 is 14dB, 0x7 is 0dB
	*
	* Bit 3 controls treble attenuation/gain (sign)
	* 1 = gain (+)
	* 0 = attenuation (-)
	*
	* Bits 4,5,6 control absolute bass gain from 0dB to 14dB
	* (This is only true for normal base range, set in 0x00)
	* 0x0 << 4 is 14dB, 0x7 is 0dB
	*
	* Bit 7 controls bass attenuation/gain (sign)
	* 1 << 7 = gain (+)
	* 0 << 7 = attenuation (-)
	*
	* Example:
	* 1 1 0 1 0 1 0 1 is +4dB bass, -4dB treble
	*/

	#define TDA7432_TREBLE_0DB 0xf
	#define TDA7432_TREBLE 7
	#define TDA7432_TREBLE_GAIN 1 << 3
	#define TDA7432_BASS_0DB 0xf
	#define TDA7432_BASS 7 << 4
	#define TDA7432_BASS_GAIN 1 << 7


	/* Subaddress 0x03 - Left Front attenuation */
	/* Subaddress 0x04 - Left Rear attenuation */
	/* Subaddress 0x05 - Right Front attenuation */
	/* Subaddress 0x06 - Right Rear attenuation */

	/* Bits 0,1,2,3,4 control attenuation from 0dB to -37.5dB
	* in 1.5dB steps.
	*
	* 0x00 is 0dB
	* 0x1f is -37.5dB
	*
	* Bit 5 mutes that channel when set (1 = mute, 0 = unmute)
	* We'll use the mute on the input, though (above)
	* Bits 6,7 unused
	*/

	#define TDA7432_ATTEN_0DB 0x00
	#define TDA7432_MUTE 0x1 << 5


	/* Subaddress 0x07 - Loudness Control */

	/* Bits 0,1,2,3 control loudness from 0dB to -15dB in 1dB steps
	* when bit 4 is NOT set
	*
	* 0x0 is 0dB
	* 0xf is -15dB
	*
	* If bit 4 is set, then there is a flat attenuation according to
	* the lower 4 bits, as above.
	*
	* Bits 5,6,7 unused
	*/



	/* Begin code */

	static int tda7432_write(struct v4l2_subdev *sd, int subaddr, int val)
	{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	unsigned char buffer[2];

	v4l2_dbg(2, debug, sd, "In tda7432_write\n");
	v4l2_dbg(1, debug, sd, "Writing %d 0x%x\n", subaddr, val);
	buffer[0] = subaddr;
	buffer[1] = val;
	if (2 != i2c_master_send(client, buffer, 2)) {
	v4l2_err(sd, "I/O error, trying (write %d 0x%x)\n",
	subaddr, val);
	return -1;
	}
	return 0;
	}

	static int tda7432_set(struct v4l2_subdev *sd)
	{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct tda7432 *t = to_state(sd);
	unsigned char buf[16];

	v4l2_dbg(1, debug, sd,
	"tda7432: 7432_set(0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x)\n",
	t->input, t->volume, t->bass, t->treble, t->lf, t->lr,
	t->rf, t->rr, t->loud);
	buf[0] = TDA7432_IN;
	buf[1] = t->input;
	buf[2] = t->volume;
	buf[3] = t->bass;
	buf[4] = t->treble;
	buf[5] = t->lf;
	buf[6] = t->lr;
	buf[7] = t->rf;
	buf[8] = t->rr;
	buf[9] = t->loud;
	if (10 != i2c_master_send(client, buf, 10)) {
	v4l2_err(sd, "I/O error, trying tda7432_set\n");
	return -1;
	}

	return 0;
	}

	static void do_tda7432_init(struct v4l2_subdev *sd)
	{
	struct tda7432 *t = to_state(sd);

	v4l2_dbg(2, debug, sd, "In tda7432_init\n");

	t->input = TDA7432_STEREO_IN \| /* Main (stereo) input */
	TDA7432_BASS_SYM \| /* Symmetric bass cut */
	TDA7432_BASS_NORM; /* Normal bass range */
	t->volume = 0x3b ; /* -27dB Volume */
	if (loudness) /* Turn loudness on? */
	t->volume \|= TDA7432_LD_ON;
	t->muted = 1;
	t->treble = TDA7432_TREBLE_0DB; /* 0dB Treble */
	t->bass = TDA7432_BASS_0DB; /* 0dB Bass */
	t->lf = TDA7432_ATTEN_0DB; /* 0dB attenuation */
	t->lr = TDA7432_ATTEN_0DB; /* 0dB attenuation */
	t->rf = TDA7432_ATTEN_0DB; /* 0dB attenuation */
	t->rr = TDA7432_ATTEN_0DB; /* 0dB attenuation */
	t->loud = loudness; /* insmod parameter */

	tda7432_set(sd);
	}

	static int tda7432_g_ctrl(struct v4l2_subdev sd, struct v4l2_control ctrl)
	{
	struct tda7432 *t = to_state(sd);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
	ctrl->value=t->muted;
	return 0;
	case V4L2_CID_AUDIO_VOLUME:
	if (!maxvol){ /* max +20db */
	ctrl->value = ( 0x6f - (t->volume & 0x7F) ) * 630;
	} else { /* max 0db */
	ctrl->value = ( 0x6f - (t->volume & 0x7F) ) * 829;
	}
	return 0;
	case V4L2_CID_AUDIO_BALANCE:
	{
	if ( (t->lf) < (t->rf) )
	/* right is attenuated, balance shifted left */
	ctrl->value = (32768 - 1057*(t->rf));
	else
	/* left is attenuated, balance shifted right */
	ctrl->value = (32768 + 1057*(t->lf));
	return 0;
	}
	case V4L2_CID_AUDIO_BASS:
	{
	/* Bass/treble 4 bits each */
	int bass=t->bass;
	if(bass >= 0x8)
	bass = ~(bass - 0x8) & 0xf;
	ctrl->value = (bass << 12)+(bass << 8)+(bass << 4)+(bass);
	return 0;
	}
	case V4L2_CID_AUDIO_TREBLE:
	{
	int treble=t->treble;
	if(treble >= 0x8)
	treble = ~(treble - 0x8) & 0xf;
	ctrl->value = (treble << 12)+(treble << 8)+(treble << 4)+(treble);
	return 0;
	}
	}
	return -EINVAL;
	}

	static int tda7432_s_ctrl(struct v4l2_subdev sd, struct v4l2_control ctrl)
	{
	struct tda7432 *t = to_state(sd);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
	t->muted=ctrl->value;
	break;
	case V4L2_CID_AUDIO_VOLUME:
	if(!maxvol){ /* max +20db */
	t->volume = 0x6f - ((ctrl->value)/630);
	} else { /* max 0db */
	t->volume = 0x6f - ((ctrl->value)/829);
	}
	if (loudness) /* Turn on the loudness bit */
	t->volume \|= TDA7432_LD_ON;

	tda7432_write(sd, TDA7432_VL, t->volume);
	return 0;
	case V4L2_CID_AUDIO_BALANCE:
	if (ctrl->value < 32768) {
	/* shifted to left, attenuate right */
	t->rr = (32768 - ctrl->value)/1057;
	t->rf = t->rr;
	t->lr = TDA7432_ATTEN_0DB;
	t->lf = TDA7432_ATTEN_0DB;
	} else if(ctrl->value > 32769) {
	/* shifted to right, attenuate left */
	t->lf = (ctrl->value - 32768)/1057;
	t->lr = t->lf;
	t->rr = TDA7432_ATTEN_0DB;
	t->rf = TDA7432_ATTEN_0DB;
	} else {
	/* centered */
	t->rr = TDA7432_ATTEN_0DB;
	t->rf = TDA7432_ATTEN_0DB;
	t->lf = TDA7432_ATTEN_0DB;
	t->lr = TDA7432_ATTEN_0DB;
	}
	break;
	case V4L2_CID_AUDIO_BASS:
	t->bass = ctrl->value >> 12;
	if(t->bass>= 0x8)
	t->bass = (~t->bass & 0xf) + 0x8 ;

	tda7432_write(sd, TDA7432_TN, 0x10 \| (t->bass << 4) \| t->treble);
	return 0;
	case V4L2_CID_AUDIO_TREBLE:
	t->treble= ctrl->value >> 12;
	if(t->treble>= 0x8)
	t->treble = (~t->treble & 0xf) + 0x8 ;

	tda7432_write(sd, TDA7432_TN, 0x10 \| (t->bass << 4) \| t->treble);
	return 0;
	default:
	return -EINVAL;
	}

	/* Used for both mute and balance changes */
	if (t->muted)
	{
	/* Mute & update balance*/
	tda7432_write(sd, TDA7432_LF, t->lf \| TDA7432_MUTE);
	tda7432_write(sd, TDA7432_LR, t->lr \| TDA7432_MUTE);
	tda7432_write(sd, TDA7432_RF, t->rf \| TDA7432_MUTE);
	tda7432_write(sd, TDA7432_RR, t->rr \| TDA7432_MUTE);
	} else {
	tda7432_write(sd, TDA7432_LF, t->lf);
	tda7432_write(sd, TDA7432_LR, t->lr);
	tda7432_write(sd, TDA7432_RF, t->rf);
	tda7432_write(sd, TDA7432_RR, t->rr);
	}
	return 0;
	}

	static int tda7432_queryctrl(struct v4l2_subdev sd, struct v4l2_queryctrl qc)
	{
	switch (qc->id) {
	case V4L2_CID_AUDIO_VOLUME:
	return v4l2_ctrl_query_fill(qc, 0, 65535, 65535 / 100, 58880);
	case V4L2_CID_AUDIO_MUTE:
	return v4l2_ctrl_query_fill(qc, 0, 1, 1, 0);
	case V4L2_CID_AUDIO_BALANCE:
	case V4L2_CID_AUDIO_BASS:
	case V4L2_CID_AUDIO_TREBLE:
	return v4l2_ctrl_query_fill(qc, 0, 65535, 65535 / 100, 32768);
	}
	return -EINVAL;
	}

	/* ----------------------------------------------------------------------- */

	static const struct v4l2_subdev_core_ops tda7432_core_ops = {
	.queryctrl = tda7432_queryctrl,
	.g_ctrl = tda7432_g_ctrl,
	.s_ctrl = tda7432_s_ctrl,
	};

	static const struct v4l2_subdev_ops tda7432_ops = {
	.core = &tda7432_core_ops,
	};

	/* ----------------------------------------------------------------------- */

	/* *********************** *
	* i2c interface functions *
	* *********************** */

	static int tda7432_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct tda7432 *t;
	struct v4l2_subdev *sd;

	v4l_info(client, "chip found @ 0x%02x (%s)\n",
	client->addr << 1, client->adapter->name);

	t = kzalloc(sizeof(*t), GFP_KERNEL);
	if (!t)
	return -ENOMEM;
	sd = &t->sd;
	v4l2_i2c_subdev_init(sd, client, &tda7432_ops);
	if (loudness < 0 \|\| loudness > 15) {
	v4l2_warn(sd, "loudness parameter must be between 0 and 15\n");
	if (loudness < 0)
	loudness = 0;
	if (loudness > 15)
	loudness = 15;
	}

	do_tda7432_init(sd);
	return 0;
	}

	static int tda7432_remove(struct i2c_client *client)
	{
	struct v4l2_subdev *sd = i2c_get_clientdata(client);

	do_tda7432_init(sd);
	v4l2_device_unregister_subdev(sd);
	kfree(to_state(sd));
	return 0;
	}

	static const struct i2c_device_id tda7432_id[] = {
	{ "tda7432", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, tda7432_id);

	static struct v4l2_i2c_driver_data v4l2_i2c_data = {
	.name = "tda7432",
	.probe = tda7432_probe,
	.remove = tda7432_remove,
	.id_table = tda7432_id,
	};