drivers/media/video/mt9v011.c - kernel/msm-4.9 - Gitiles

 /*
  * mt9v011 -Micron 1/4-Inch VGA Digital Image Sensor
  *
  * Copyright (c) 2009 Mauro Carvalho Chehab (mchehab@redhat.com)
  * This code is placed under the terms of the GNU General Public License v2
  */

 #include <linux/i2c.h>
 #include <linux/slab.h>
 #include <linux/videodev2.h>
 #include <linux/delay.h>
 #include <asm/div64.h>
 #include <media/v4l2-device.h>
 #include "mt9v011.h"
 #include <media/v4l2-i2c-drv.h>
 #include <media/v4l2-chip-ident.h>

 MODULE_DESCRIPTION("Micron mt9v011 sensor driver");
 MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
 MODULE_LICENSE("GPL");


 static int debug;
 module_param(debug, int, 0);
 MODULE_PARM_DESC(debug, "Debug level (0-2)");

 /* supported controls */
 static struct v4l2_queryctrl mt9v011_qctrl[] = {
 	{
 		.id = V4L2_CID_GAIN,
 		.type = V4L2_CTRL_TYPE_INTEGER,
 		.name = "Gain",
 		.minimum = 0,
 		.maximum = (1 << 10) - 1,
 		.step = 1,
 		.default_value = 0x0020,
 		.flags = 0,
 	}, {
 		.id = V4L2_CID_RED_BALANCE,
 		.type = V4L2_CTRL_TYPE_INTEGER,
 		.name = "Red Balance",
 		.minimum = -1 << 9,
 		.maximum = (1 << 9) - 1,
 		.step = 1,
 		.default_value = 0,
 		.flags = 0,
 	}, {
 		.id = V4L2_CID_BLUE_BALANCE,
 		.type = V4L2_CTRL_TYPE_INTEGER,
 		.name = "Blue Balance",
 		.minimum = -1 << 9,
 		.maximum = (1 << 9) - 1,
 		.step = 1,
 		.default_value = 0,
 		.flags = 0,
 	}, {
 		.id      = V4L2_CID_HFLIP,
 		.type    = V4L2_CTRL_TYPE_BOOLEAN,
 		.name    = "Mirror",
 		.minimum = 0,
 		.maximum = 1,
 		.step    = 1,
 		.default_value = 0,
 		.flags = 0,
 	}, {
 		.id      = V4L2_CID_VFLIP,
 		.type    = V4L2_CTRL_TYPE_BOOLEAN,
 		.name    = "Vflip",
 		.minimum = 0,
 		.maximum = 1,
 		.step    = 1,
 		.default_value = 0,
 		.flags = 0,
 	}, {
 	}
 };

 struct mt9v011 {
 	struct v4l2_subdev sd;
 	unsigned width, height;
 	unsigned xtal;
 	unsigned hflip:1;
 	unsigned vflip:1;

 	u16 global_gain, red_bal, blue_bal;
 };

 static inline struct mt9v011 *to_mt9v011(struct v4l2_subdev *sd)
 {
 	return container_of(sd, struct mt9v011, sd);
 }

 static int mt9v011_read(struct v4l2_subdev *sd, unsigned char addr)
 {
 	struct i2c_client *c = v4l2_get_subdevdata(sd);
 	__be16 buffer;
 	int rc, val;

 	rc = i2c_master_send(c, &addr, 1);
 	if (rc != 1)
 		v4l2_dbg(0, debug, sd,
 			 "i2c i/o error: rc == %d (should be 1)\n", rc);

 	msleep(10);

 	rc = i2c_master_recv(c, (char *)&buffer, 2);
 	if (rc != 2)
 		v4l2_dbg(0, debug, sd,
 			 "i2c i/o error: rc == %d (should be 2)\n", rc);

 	val = be16_to_cpu(buffer);

 	v4l2_dbg(2, debug, sd, "mt9v011: read 0x%02x = 0x%04x\n", addr, val);

 	return val;
 }

 static void mt9v011_write(struct v4l2_subdev *sd, unsigned char addr,
 				 u16 value)
 {
 	struct i2c_client *c = v4l2_get_subdevdata(sd);
 	unsigned char buffer[3];
 	int rc;

 	buffer[0] = addr;
 	buffer[1] = value >> 8;
 	buffer[2] = value & 0xff;

 	v4l2_dbg(2, debug, sd,
 		 "mt9v011: writing 0x%02x 0x%04x\n", buffer[0], value);
 	rc = i2c_master_send(c, buffer, 3);
 	if (rc != 3)
 		v4l2_dbg(0, debug, sd,
 			 "i2c i/o error: rc == %d (should be 3)\n", rc);
 }


 struct i2c_reg_value {
 	unsigned char reg;
 	u16           value;
 };

 /*
  * Values used at the original driver
  * Some values are marked as Reserved at the datasheet
  */
 static const struct i2c_reg_value mt9v011_init_default[] = {
 		{ R0D_MT9V011_RESET, 0x0001 },
 		{ R0D_MT9V011_RESET, 0x0000 },

 		{ R0C_MT9V011_SHUTTER_DELAY, 0x0000 },
 		{ R09_MT9V011_SHUTTER_WIDTH, 0x1fc },

 		{ R0A_MT9V011_CLK_SPEED, 0x0000 },
 		{ R1E_MT9V011_DIGITAL_ZOOM,  0x0000 },

 		{ R07_MT9V011_OUT_CTRL, 0x0002 },	/* chip enable */
 };

 static void set_balance(struct v4l2_subdev *sd)
 {
 	struct mt9v011 *core = to_mt9v011(sd);
 	u16 green1_gain, green2_gain, blue_gain, red_gain;

 	green1_gain = core->global_gain;
 	green2_gain = core->global_gain;

 	blue_gain = core->global_gain +
 		    core->global_gain * core->blue_bal / (1 << 9);

 	red_gain = core->global_gain +
 		   core->global_gain * core->blue_bal / (1 << 9);

 	mt9v011_write(sd, R2B_MT9V011_GREEN_1_GAIN, green1_gain);
 	mt9v011_write(sd, R2E_MT9V011_GREEN_2_GAIN,  green1_gain);
 	mt9v011_write(sd, R2C_MT9V011_BLUE_GAIN, blue_gain);
 	mt9v011_write(sd, R2D_MT9V011_RED_GAIN, red_gain);
 }

 static void calc_fps(struct v4l2_subdev *sd, u32 *numerator, u32 *denominator)
 {
 	struct mt9v011 *core = to_mt9v011(sd);
 	unsigned height, width, hblank, vblank, speed;
 	unsigned row_time, t_time;
 	u64 frames_per_ms;
 	unsigned tmp;

 	height = mt9v011_read(sd, R03_MT9V011_HEIGHT);
 	width = mt9v011_read(sd, R04_MT9V011_WIDTH);
 	hblank = mt9v011_read(sd, R05_MT9V011_HBLANK);
 	vblank = mt9v011_read(sd, R06_MT9V011_VBLANK);
 	speed = mt9v011_read(sd, R0A_MT9V011_CLK_SPEED);

 	row_time = (width + 113 + hblank) * (speed + 2);
 	t_time = row_time * (height + vblank + 1);

 	frames_per_ms = core->xtal * 1000l;
 	do_div(frames_per_ms, t_time);
 	tmp = frames_per_ms;

 	v4l2_dbg(1, debug, sd, "Programmed to %u.%03u fps (%d pixel clcks)\n",
 		tmp / 1000, tmp % 1000, t_time);

 	if (numerator && denominator) {
 		*numerator = 1000;
 		*denominator = (u32)frames_per_ms;
 	}
 }

 static u16 calc_speed(struct v4l2_subdev *sd, u32 numerator, u32 denominator)
 {
 	struct mt9v011 *core = to_mt9v011(sd);
 	unsigned height, width, hblank, vblank;
 	unsigned row_time, line_time;
 	u64 t_time, speed;

 	/* Avoid bogus calculus */
 	if (!numerator || !denominator)
 		return 0;

 	height = mt9v011_read(sd, R03_MT9V011_HEIGHT);
 	width = mt9v011_read(sd, R04_MT9V011_WIDTH);
 	hblank = mt9v011_read(sd, R05_MT9V011_HBLANK);
 	vblank = mt9v011_read(sd, R06_MT9V011_VBLANK);

 	row_time = width + 113 + hblank;
 	line_time = height + vblank + 1;

 	t_time = core->xtal * ((u64)numerator);
 	/* round to the closest value */
 	t_time += denominator / 2;
 	do_div(t_time, denominator);

 	speed = t_time;
 	do_div(speed, row_time * line_time);

 	/* Avoid having a negative value for speed */
 	if (speed < 2)
 		speed = 0;
 	else
 		speed -= 2;

 	/* Avoid speed overflow */
 	if (speed > 15)
 		return 15;

 	return (u16)speed;
 }

 static void set_res(struct v4l2_subdev *sd)
 {
 	struct mt9v011 *core = to_mt9v011(sd);
 	unsigned vstart, hstart;

 	/*
 	 * The mt9v011 doesn't have scaling. So, in order to select the desired
 	 * resolution, we're cropping at the middle of the sensor.
 	 * hblank and vblank should be adjusted, in order to warrant that
 	 * we'll preserve the line timings for 30 fps, no matter what resolution
 	 * is selected.
 	 * NOTE: datasheet says that width (and height) should be filled with
 	 * width-1. However, this doesn't work, since one pixel per line will
 	 * be missing.
 	 */

 	hstart = 14 + (640 - core->width) / 2;
 	mt9v011_write(sd, R02_MT9V011_COLSTART, hstart);
 	mt9v011_write(sd, R04_MT9V011_WIDTH, core->width);
 	mt9v011_write(sd, R05_MT9V011_HBLANK, 771 - core->width);

 	vstart = 8 + (480 - core->height) / 2;
 	mt9v011_write(sd, R01_MT9V011_ROWSTART, vstart);
 	mt9v011_write(sd, R03_MT9V011_HEIGHT, core->height);
 	mt9v011_write(sd, R06_MT9V011_VBLANK, 508 - core->height);

 	calc_fps(sd, NULL, NULL);
 };

 static void set_read_mode(struct v4l2_subdev *sd)
 {
 	struct mt9v011 *core = to_mt9v011(sd);
 	unsigned mode = 0x1000;

 	if (core->hflip)
 		mode |= 0x4000;

 	if (core->vflip)
 		mode |= 0x8000;

 	mt9v011_write(sd, R20_MT9V011_READ_MODE, mode);
 }

 static int mt9v011_reset(struct v4l2_subdev *sd, u32 val)
 {
 	int i;

 	for (i = 0; i < ARRAY_SIZE(mt9v011_init_default); i++)
 		mt9v011_write(sd, mt9v011_init_default[i].reg,
 			       mt9v011_init_default[i].value);

 	set_balance(sd);
 	set_res(sd);
 	set_read_mode(sd);

 	return 0;
 };

 static int mt9v011_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 {
 	struct mt9v011 *core = to_mt9v011(sd);

 	v4l2_dbg(1, debug, sd, "g_ctrl called\n");

 	switch (ctrl->id) {
 	case V4L2_CID_GAIN:
 		ctrl->value = core->global_gain;
 		return 0;
 	case V4L2_CID_RED_BALANCE:
 		ctrl->value = core->red_bal;
 		return 0;
 	case V4L2_CID_BLUE_BALANCE:
 		ctrl->value = core->blue_bal;
 		return 0;
 	case V4L2_CID_HFLIP:
 		ctrl->value = core->hflip ? 1 : 0;
 		return 0;
 	case V4L2_CID_VFLIP:
 		ctrl->value = core->vflip ? 1 : 0;
 		return 0;
 	}
 	return -EINVAL;
 }

 static int mt9v011_queryctrl(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc)
 {
 	int i;

 	v4l2_dbg(1, debug, sd, "queryctrl called\n");

 	for (i = 0; i < ARRAY_SIZE(mt9v011_qctrl); i++)
 		if (qc->id && qc->id == mt9v011_qctrl[i].id) {
 			memcpy(qc, &(mt9v011_qctrl[i]),
 			       sizeof(*qc));
 			return 0;
 		}

 	return -EINVAL;
 }


 static int mt9v011_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 {
 	struct mt9v011 *core = to_mt9v011(sd);
 	u8 i, n;
 	n = ARRAY_SIZE(mt9v011_qctrl);

 	for (i = 0; i < n; i++) {
 		if (ctrl->id != mt9v011_qctrl[i].id)
 			continue;
 		if (ctrl->value < mt9v011_qctrl[i].minimum ||
 		    ctrl->value > mt9v011_qctrl[i].maximum)
 			return -ERANGE;
 		v4l2_dbg(1, debug, sd, "s_ctrl: id=%d, value=%d\n",
 					ctrl->id, ctrl->value);
 		break;
 	}

 	switch (ctrl->id) {
 	case V4L2_CID_GAIN:
 		core->global_gain = ctrl->value;
 		break;
 	case V4L2_CID_RED_BALANCE:
 		core->red_bal = ctrl->value;
 		break;
 	case V4L2_CID_BLUE_BALANCE:
 		core->blue_bal = ctrl->value;
 		break;
 	case V4L2_CID_HFLIP:
 		core->hflip = ctrl->value;
 		set_read_mode(sd);
 		return 0;
 	case V4L2_CID_VFLIP:
 		core->vflip = ctrl->value;
 		set_read_mode(sd);
 		return 0;
 	default:
 		return -EINVAL;
 	}

 	set_balance(sd);

 	return 0;
 }

 static int mt9v011_enum_fmt(struct v4l2_subdev *sd, struct v4l2_fmtdesc *fmt)
 {
 	if (fmt->index > 0)
 		return -EINVAL;

 	fmt->flags = 0;
 	strcpy(fmt->description, "8 bpp Bayer GRGR..BGBG");
 	fmt->pixelformat = V4L2_PIX_FMT_SGRBG8;

 	return 0;
 }

 static int mt9v011_try_fmt(struct v4l2_subdev *sd, struct v4l2_format *fmt)
 {
 	struct v4l2_pix_format *pix = &fmt->fmt.pix;

 	if (pix->pixelformat != V4L2_PIX_FMT_SGRBG8)
 		return -EINVAL;

 	v4l_bound_align_image(&pix->width, 48, 639, 1,
 			      &pix->height, 32, 480, 1, 0);

 	return 0;
 }

 static int mt9v011_g_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
 {
 	struct v4l2_captureparm *cp = &parms->parm.capture;

 	if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 		return -EINVAL;

 	memset(cp, 0, sizeof(struct v4l2_captureparm));
 	cp->capability = V4L2_CAP_TIMEPERFRAME;
 	calc_fps(sd,
 		 &cp->timeperframe.numerator,
 		 &cp->timeperframe.denominator);

 	return 0;
 }

 static int mt9v011_s_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
 {
 	struct v4l2_captureparm *cp = &parms->parm.capture;
 	struct v4l2_fract *tpf = &cp->timeperframe;
 	u16 speed;

 	if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 		return -EINVAL;
 	if (cp->extendedmode != 0)
 		return -EINVAL;

 	speed = calc_speed(sd, tpf->numerator, tpf->denominator);

 	mt9v011_write(sd, R0A_MT9V011_CLK_SPEED, speed);
 	v4l2_dbg(1, debug, sd, "Setting speed to %d\n", speed);

 	/* Recalculate and update fps info */
 	calc_fps(sd, &tpf->numerator, &tpf->denominator);

 	return 0;
 }

 static int mt9v011_s_fmt(struct v4l2_subdev *sd, struct v4l2_format *fmt)
 {
 	struct v4l2_pix_format *pix = &fmt->fmt.pix;
 	struct mt9v011 *core = to_mt9v011(sd);
 	int rc;

 	rc = mt9v011_try_fmt(sd, fmt);
 	if (rc < 0)
 		return -EINVAL;

 	core->width = pix->width;
 	core->height = pix->height;

 	set_res(sd);

 	return 0;
 }

 static int mt9v011_s_config(struct v4l2_subdev *sd, int dumb, void *data)
 {
 	struct mt9v011 *core = to_mt9v011(sd);
 	unsigned *xtal = data;

 	v4l2_dbg(1, debug, sd, "s_config called\n");

 	if (xtal) {
 		core->xtal = *xtal;
 		v4l2_dbg(1, debug, sd, "xtal set to %d.%03d MHz\n",
 			 *xtal / 1000000, (*xtal / 1000) % 1000);
 	}

 	return 0;
 }


 #ifdef CONFIG_VIDEO_ADV_DEBUG
 static int mt9v011_g_register(struct v4l2_subdev *sd,
 			      struct v4l2_dbg_register *reg)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(sd);

 	if (!v4l2_chip_match_i2c_client(client, &reg->match))
 		return -EINVAL;
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;

 	reg->val = mt9v011_read(sd, reg->reg & 0xff);
 	reg->size = 2;

 	return 0;
 }

 static int mt9v011_s_register(struct v4l2_subdev *sd,
 			      struct v4l2_dbg_register *reg)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(sd);

 	if (!v4l2_chip_match_i2c_client(client, &reg->match))
 		return -EINVAL;
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;

 	mt9v011_write(sd, reg->reg & 0xff, reg->val & 0xffff);

 	return 0;
 }
 #endif

 static int mt9v011_g_chip_ident(struct v4l2_subdev *sd,
 				struct v4l2_dbg_chip_ident *chip)
 {
 	u16 version;
 	struct i2c_client *client = v4l2_get_subdevdata(sd);

 	version = mt9v011_read(sd, R00_MT9V011_CHIP_VERSION);

 	return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_MT9V011,
 					  version);
 }

 static const struct v4l2_subdev_core_ops mt9v011_core_ops = {
 	.queryctrl = mt9v011_queryctrl,
 	.g_ctrl = mt9v011_g_ctrl,
 	.s_ctrl = mt9v011_s_ctrl,
 	.reset = mt9v011_reset,
 	.s_config = mt9v011_s_config,
 	.g_chip_ident = mt9v011_g_chip_ident,
 #ifdef CONFIG_VIDEO_ADV_DEBUG
 	.g_register = mt9v011_g_register,
 	.s_register = mt9v011_s_register,
 #endif
 };

 static const struct v4l2_subdev_video_ops mt9v011_video_ops = {
 	.enum_fmt = mt9v011_enum_fmt,
 	.try_fmt = mt9v011_try_fmt,
 	.s_fmt = mt9v011_s_fmt,
 	.g_parm = mt9v011_g_parm,
 	.s_parm = mt9v011_s_parm,
 };

 static const struct v4l2_subdev_ops mt9v011_ops = {
 	.core  = &mt9v011_core_ops,
 	.video = &mt9v011_video_ops,
 };


 /****************************************************************************
 			I2C Client & Driver
  ****************************************************************************/

 static int mt9v011_probe(struct i2c_client *c,
 			 const struct i2c_device_id *id)
 {
 	u16 version;
 	struct mt9v011 *core;
 	struct v4l2_subdev *sd;

 	/* Check if the adapter supports the needed features */
 	if (!i2c_check_functionality(c->adapter,
 	     I2C_FUNC_SMBUS_READ_BYTE | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
 		return -EIO;

 	core = kzalloc(sizeof(struct mt9v011), GFP_KERNEL);
 	if (!core)
 		return -ENOMEM;

 	sd = &core->sd;
 	v4l2_i2c_subdev_init(sd, c, &mt9v011_ops);

 	/* Check if the sensor is really a MT9V011 */
 	version = mt9v011_read(sd, R00_MT9V011_CHIP_VERSION);
 	if ((version != MT9V011_VERSION) &&
 	    (version != MT9V011_REV_B_VERSION)) {
 		v4l2_info(sd, "*** unknown micron chip detected (0x%04x).\n",
 			  version);
 		kfree(core);
 		return -EINVAL;
 	}

 	core->global_gain = 0x0024;
 	core->width  = 640;
 	core->height = 480;
 	core->xtal = 27000000;	/* Hz */

 	v4l_info(c, "chip found @ 0x%02x (%s - chip version 0x%04x)\n",
 		 c->addr << 1, c->adapter->name, version);

 	return 0;
 }

 static int mt9v011_remove(struct i2c_client *c)
 {
 	struct v4l2_subdev *sd = i2c_get_clientdata(c);

 	v4l2_dbg(1, debug, sd,
 		"mt9v011.c: removing mt9v011 adapter on address 0x%x\n",
 		c->addr << 1);

 	v4l2_device_unregister_subdev(sd);
 	kfree(to_mt9v011(sd));
 	return 0;
 }

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

 static const struct i2c_device_id mt9v011_id[] = {
 	{ "mt9v011", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, mt9v011_id);

 static struct v4l2_i2c_driver_data v4l2_i2c_data = {
 	.name = "mt9v011",
 	.probe = mt9v011_probe,
 	.remove = mt9v011_remove,
 	.id_table = mt9v011_id,
 };
	/*
	* mt9v011 -Micron 1/4-Inch VGA Digital Image Sensor
	*
	* Copyright (c) 2009 Mauro Carvalho Chehab (mchehab@redhat.com)
	* This code is placed under the terms of the GNU General Public License v2
	*/

	#include <linux/i2c.h>
	#include <linux/slab.h>
	#include <linux/videodev2.h>
	#include <linux/delay.h>
	#include <asm/div64.h>
	#include <media/v4l2-device.h>
	#include "mt9v011.h"
	#include <media/v4l2-i2c-drv.h>
	#include <media/v4l2-chip-ident.h>

	MODULE_DESCRIPTION("Micron mt9v011 sensor driver");
	MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
	MODULE_LICENSE("GPL");


	static int debug;
	module_param(debug, int, 0);
	MODULE_PARM_DESC(debug, "Debug level (0-2)");

	/* supported controls */
	static struct v4l2_queryctrl mt9v011_qctrl[] = {
	{
	.id = V4L2_CID_GAIN,
	.type = V4L2_CTRL_TYPE_INTEGER,
	.name = "Gain",
	.minimum = 0,
	.maximum = (1 << 10) - 1,
	.step = 1,
	.default_value = 0x0020,
	.flags = 0,
	}, {
	.id = V4L2_CID_RED_BALANCE,
	.type = V4L2_CTRL_TYPE_INTEGER,
	.name = "Red Balance",
	.minimum = -1 << 9,
	.maximum = (1 << 9) - 1,
	.step = 1,
	.default_value = 0,
	.flags = 0,
	}, {
	.id = V4L2_CID_BLUE_BALANCE,
	.type = V4L2_CTRL_TYPE_INTEGER,
	.name = "Blue Balance",
	.minimum = -1 << 9,
	.maximum = (1 << 9) - 1,
	.step = 1,
	.default_value = 0,
	.flags = 0,
	}, {
	.id = V4L2_CID_HFLIP,
	.type = V4L2_CTRL_TYPE_BOOLEAN,
	.name = "Mirror",
	.minimum = 0,
	.maximum = 1,
	.step = 1,
	.default_value = 0,
	.flags = 0,
	}, {
	.id = V4L2_CID_VFLIP,
	.type = V4L2_CTRL_TYPE_BOOLEAN,
	.name = "Vflip",
	.minimum = 0,
	.maximum = 1,
	.step = 1,
	.default_value = 0,
	.flags = 0,
	}, {
	}
	};

	struct mt9v011 {
	struct v4l2_subdev sd;
	unsigned width, height;
	unsigned xtal;
	unsigned hflip:1;
	unsigned vflip:1;

	u16 global_gain, red_bal, blue_bal;
	};

	static inline struct mt9v011 to_mt9v011(struct v4l2_subdev sd)
	{
	return container_of(sd, struct mt9v011, sd);
	}

	static int mt9v011_read(struct v4l2_subdev *sd, unsigned char addr)
	{
	struct i2c_client *c = v4l2_get_subdevdata(sd);
	__be16 buffer;
	int rc, val;

	rc = i2c_master_send(c, &addr, 1);
	if (rc != 1)
	v4l2_dbg(0, debug, sd,
	"i2c i/o error: rc == %d (should be 1)\n", rc);

	msleep(10);

	rc = i2c_master_recv(c, (char *)&buffer, 2);
	if (rc != 2)
	v4l2_dbg(0, debug, sd,
	"i2c i/o error: rc == %d (should be 2)\n", rc);

	val = be16_to_cpu(buffer);

	v4l2_dbg(2, debug, sd, "mt9v011: read 0x%02x = 0x%04x\n", addr, val);

	return val;
	}

	static void mt9v011_write(struct v4l2_subdev *sd, unsigned char addr,
	u16 value)
	{
	struct i2c_client *c = v4l2_get_subdevdata(sd);
	unsigned char buffer[3];
	int rc;

	buffer[0] = addr;
	buffer[1] = value >> 8;
	buffer[2] = value & 0xff;

	v4l2_dbg(2, debug, sd,
	"mt9v011: writing 0x%02x 0x%04x\n", buffer[0], value);
	rc = i2c_master_send(c, buffer, 3);
	if (rc != 3)
	v4l2_dbg(0, debug, sd,
	"i2c i/o error: rc == %d (should be 3)\n", rc);
	}


	struct i2c_reg_value {
	unsigned char reg;
	u16 value;
	};

	/*
	* Values used at the original driver
	* Some values are marked as Reserved at the datasheet
	*/
	static const struct i2c_reg_value mt9v011_init_default[] = {
	{ R0D_MT9V011_RESET, 0x0001 },
	{ R0D_MT9V011_RESET, 0x0000 },

	{ R0C_MT9V011_SHUTTER_DELAY, 0x0000 },
	{ R09_MT9V011_SHUTTER_WIDTH, 0x1fc },

	{ R0A_MT9V011_CLK_SPEED, 0x0000 },
	{ R1E_MT9V011_DIGITAL_ZOOM, 0x0000 },

	{ R07_MT9V011_OUT_CTRL, 0x0002 }, /* chip enable */
	};

	static void set_balance(struct v4l2_subdev *sd)
	{
	struct mt9v011 *core = to_mt9v011(sd);
	u16 green1_gain, green2_gain, blue_gain, red_gain;

	green1_gain = core->global_gain;
	green2_gain = core->global_gain;

	blue_gain = core->global_gain +
	core->global_gain * core->blue_bal / (1 << 9);

	red_gain = core->global_gain +
	core->global_gain * core->blue_bal / (1 << 9);

	mt9v011_write(sd, R2B_MT9V011_GREEN_1_GAIN, green1_gain);
	mt9v011_write(sd, R2E_MT9V011_GREEN_2_GAIN, green1_gain);
	mt9v011_write(sd, R2C_MT9V011_BLUE_GAIN, blue_gain);
	mt9v011_write(sd, R2D_MT9V011_RED_GAIN, red_gain);
	}

	static void calc_fps(struct v4l2_subdev sd, u32 numerator, u32 *denominator)
	{
	struct mt9v011 *core = to_mt9v011(sd);
	unsigned height, width, hblank, vblank, speed;
	unsigned row_time, t_time;
	u64 frames_per_ms;
	unsigned tmp;

	height = mt9v011_read(sd, R03_MT9V011_HEIGHT);
	width = mt9v011_read(sd, R04_MT9V011_WIDTH);
	hblank = mt9v011_read(sd, R05_MT9V011_HBLANK);
	vblank = mt9v011_read(sd, R06_MT9V011_VBLANK);
	speed = mt9v011_read(sd, R0A_MT9V011_CLK_SPEED);

	row_time = (width + 113 + hblank) * (speed + 2);
	t_time = row_time * (height + vblank + 1);

	frames_per_ms = core->xtal * 1000l;
	do_div(frames_per_ms, t_time);
	tmp = frames_per_ms;

	v4l2_dbg(1, debug, sd, "Programmed to %u.%03u fps (%d pixel clcks)\n",
	tmp / 1000, tmp % 1000, t_time);

	if (numerator && denominator) {
	*numerator = 1000;
	*denominator = (u32)frames_per_ms;
	}
	}

	static u16 calc_speed(struct v4l2_subdev *sd, u32 numerator, u32 denominator)
	{
	struct mt9v011 *core = to_mt9v011(sd);
	unsigned height, width, hblank, vblank;
	unsigned row_time, line_time;
	u64 t_time, speed;

	/* Avoid bogus calculus */
	if (!numerator \|\| !denominator)
	return 0;

	height = mt9v011_read(sd, R03_MT9V011_HEIGHT);
	width = mt9v011_read(sd, R04_MT9V011_WIDTH);
	hblank = mt9v011_read(sd, R05_MT9V011_HBLANK);
	vblank = mt9v011_read(sd, R06_MT9V011_VBLANK);

	row_time = width + 113 + hblank;
	line_time = height + vblank + 1;

	t_time = core->xtal * ((u64)numerator);
	/* round to the closest value */
	t_time += denominator / 2;
	do_div(t_time, denominator);

	speed = t_time;
	do_div(speed, row_time * line_time);

	/* Avoid having a negative value for speed */
	if (speed < 2)
	speed = 0;
	else
	speed -= 2;

	/* Avoid speed overflow */
	if (speed > 15)
	return 15;

	return (u16)speed;
	}

	static void set_res(struct v4l2_subdev *sd)
	{
	struct mt9v011 *core = to_mt9v011(sd);
	unsigned vstart, hstart;

	/*
	* The mt9v011 doesn't have scaling. So, in order to select the desired
	* resolution, we're cropping at the middle of the sensor.
	* hblank and vblank should be adjusted, in order to warrant that
	* we'll preserve the line timings for 30 fps, no matter what resolution
	* is selected.
	* NOTE: datasheet says that width (and height) should be filled with
	* width-1. However, this doesn't work, since one pixel per line will
	* be missing.
	*/

	hstart = 14 + (640 - core->width) / 2;
	mt9v011_write(sd, R02_MT9V011_COLSTART, hstart);
	mt9v011_write(sd, R04_MT9V011_WIDTH, core->width);
	mt9v011_write(sd, R05_MT9V011_HBLANK, 771 - core->width);

	vstart = 8 + (480 - core->height) / 2;
	mt9v011_write(sd, R01_MT9V011_ROWSTART, vstart);
	mt9v011_write(sd, R03_MT9V011_HEIGHT, core->height);
	mt9v011_write(sd, R06_MT9V011_VBLANK, 508 - core->height);

	calc_fps(sd, NULL, NULL);
	};

	static void set_read_mode(struct v4l2_subdev *sd)
	{
	struct mt9v011 *core = to_mt9v011(sd);
	unsigned mode = 0x1000;

	if (core->hflip)
	mode \|= 0x4000;

	if (core->vflip)
	mode \|= 0x8000;

	mt9v011_write(sd, R20_MT9V011_READ_MODE, mode);
	}

	static int mt9v011_reset(struct v4l2_subdev *sd, u32 val)
	{
	int i;

	for (i = 0; i < ARRAY_SIZE(mt9v011_init_default); i++)
	mt9v011_write(sd, mt9v011_init_default[i].reg,
	mt9v011_init_default[i].value);

	set_balance(sd);
	set_res(sd);
	set_read_mode(sd);

	return 0;
	};

	static int mt9v011_g_ctrl(struct v4l2_subdev sd, struct v4l2_control ctrl)
	{
	struct mt9v011 *core = to_mt9v011(sd);

	v4l2_dbg(1, debug, sd, "g_ctrl called\n");

	switch (ctrl->id) {
	case V4L2_CID_GAIN:
	ctrl->value = core->global_gain;
	return 0;
	case V4L2_CID_RED_BALANCE:
	ctrl->value = core->red_bal;
	return 0;
	case V4L2_CID_BLUE_BALANCE:
	ctrl->value = core->blue_bal;
	return 0;
	case V4L2_CID_HFLIP:
	ctrl->value = core->hflip ? 1 : 0;
	return 0;
	case V4L2_CID_VFLIP:
	ctrl->value = core->vflip ? 1 : 0;
	return 0;
	}
	return -EINVAL;
	}

	static int mt9v011_queryctrl(struct v4l2_subdev sd, struct v4l2_queryctrl qc)
	{
	int i;

	v4l2_dbg(1, debug, sd, "queryctrl called\n");

	for (i = 0; i < ARRAY_SIZE(mt9v011_qctrl); i++)
	if (qc->id && qc->id == mt9v011_qctrl[i].id) {
	memcpy(qc, &(mt9v011_qctrl[i]),
	sizeof(*qc));
	return 0;
	}

	return -EINVAL;
	}


	static int mt9v011_s_ctrl(struct v4l2_subdev sd, struct v4l2_control ctrl)
	{
	struct mt9v011 *core = to_mt9v011(sd);
	u8 i, n;
	n = ARRAY_SIZE(mt9v011_qctrl);

	for (i = 0; i < n; i++) {
	if (ctrl->id != mt9v011_qctrl[i].id)
	continue;
	if (ctrl->value < mt9v011_qctrl[i].minimum \|\|
	ctrl->value > mt9v011_qctrl[i].maximum)
	return -ERANGE;
	v4l2_dbg(1, debug, sd, "s_ctrl: id=%d, value=%d\n",
	ctrl->id, ctrl->value);
	break;
	}

	switch (ctrl->id) {
	case V4L2_CID_GAIN:
	core->global_gain = ctrl->value;
	break;
	case V4L2_CID_RED_BALANCE:
	core->red_bal = ctrl->value;
	break;
	case V4L2_CID_BLUE_BALANCE:
	core->blue_bal = ctrl->value;
	break;
	case V4L2_CID_HFLIP:
	core->hflip = ctrl->value;
	set_read_mode(sd);
	return 0;
	case V4L2_CID_VFLIP:
	core->vflip = ctrl->value;
	set_read_mode(sd);
	return 0;
	default:
	return -EINVAL;
	}

	set_balance(sd);

	return 0;
	}

	static int mt9v011_enum_fmt(struct v4l2_subdev sd, struct v4l2_fmtdesc fmt)
	{
	if (fmt->index > 0)
	return -EINVAL;

	fmt->flags = 0;
	strcpy(fmt->description, "8 bpp Bayer GRGR..BGBG");
	fmt->pixelformat = V4L2_PIX_FMT_SGRBG8;

	return 0;
	}

	static int mt9v011_try_fmt(struct v4l2_subdev sd, struct v4l2_format fmt)
	{
	struct v4l2_pix_format *pix = &fmt->fmt.pix;

	if (pix->pixelformat != V4L2_PIX_FMT_SGRBG8)
	return -EINVAL;

	v4l_bound_align_image(&pix->width, 48, 639, 1,
	&pix->height, 32, 480, 1, 0);

	return 0;
	}

	static int mt9v011_g_parm(struct v4l2_subdev sd, struct v4l2_streamparm parms)
	{
	struct v4l2_captureparm *cp = &parms->parm.capture;

	if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
	return -EINVAL;

	memset(cp, 0, sizeof(struct v4l2_captureparm));
	cp->capability = V4L2_CAP_TIMEPERFRAME;
	calc_fps(sd,
	&cp->timeperframe.numerator,
	&cp->timeperframe.denominator);

	return 0;
	}

	static int mt9v011_s_parm(struct v4l2_subdev sd, struct v4l2_streamparm parms)
	{
	struct v4l2_captureparm *cp = &parms->parm.capture;
	struct v4l2_fract *tpf = &cp->timeperframe;
	u16 speed;

	if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
	return -EINVAL;
	if (cp->extendedmode != 0)
	return -EINVAL;

	speed = calc_speed(sd, tpf->numerator, tpf->denominator);

	mt9v011_write(sd, R0A_MT9V011_CLK_SPEED, speed);
	v4l2_dbg(1, debug, sd, "Setting speed to %d\n", speed);

	/* Recalculate and update fps info */
	calc_fps(sd, &tpf->numerator, &tpf->denominator);

	return 0;
	}

	static int mt9v011_s_fmt(struct v4l2_subdev sd, struct v4l2_format fmt)
	{
	struct v4l2_pix_format *pix = &fmt->fmt.pix;
	struct mt9v011 *core = to_mt9v011(sd);
	int rc;

	rc = mt9v011_try_fmt(sd, fmt);
	if (rc < 0)
	return -EINVAL;

	core->width = pix->width;
	core->height = pix->height;

	set_res(sd);

	return 0;
	}

	static int mt9v011_s_config(struct v4l2_subdev sd, int dumb, void data)
	{
	struct mt9v011 *core = to_mt9v011(sd);
	unsigned *xtal = data;

	v4l2_dbg(1, debug, sd, "s_config called\n");

	if (xtal) {
	core->xtal = *xtal;
	v4l2_dbg(1, debug, sd, "xtal set to %d.%03d MHz\n",
	xtal / 1000000, (xtal / 1000) % 1000);
	}

	return 0;
	}


	#ifdef CONFIG_VIDEO_ADV_DEBUG
	static int mt9v011_g_register(struct v4l2_subdev *sd,
	struct v4l2_dbg_register *reg)
	{
	struct i2c_client *client = v4l2_get_subdevdata(sd);

	if (!v4l2_chip_match_i2c_client(client, &reg->match))
	return -EINVAL;
	if (!capable(CAP_SYS_ADMIN))
	return -EPERM;

	reg->val = mt9v011_read(sd, reg->reg & 0xff);
	reg->size = 2;

	return 0;
	}

	static int mt9v011_s_register(struct v4l2_subdev *sd,
	struct v4l2_dbg_register *reg)
	{
	struct i2c_client *client = v4l2_get_subdevdata(sd);

	if (!v4l2_chip_match_i2c_client(client, &reg->match))
	return -EINVAL;
	if (!capable(CAP_SYS_ADMIN))
	return -EPERM;

	mt9v011_write(sd, reg->reg & 0xff, reg->val & 0xffff);

	return 0;
	}
	#endif

	static int mt9v011_g_chip_ident(struct v4l2_subdev *sd,
	struct v4l2_dbg_chip_ident *chip)
	{
	u16 version;
	struct i2c_client *client = v4l2_get_subdevdata(sd);

	version = mt9v011_read(sd, R00_MT9V011_CHIP_VERSION);

	return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_MT9V011,
	version);
	}

	static const struct v4l2_subdev_core_ops mt9v011_core_ops = {
	.queryctrl = mt9v011_queryctrl,
	.g_ctrl = mt9v011_g_ctrl,
	.s_ctrl = mt9v011_s_ctrl,
	.reset = mt9v011_reset,
	.s_config = mt9v011_s_config,
	.g_chip_ident = mt9v011_g_chip_ident,
	#ifdef CONFIG_VIDEO_ADV_DEBUG
	.g_register = mt9v011_g_register,
	.s_register = mt9v011_s_register,
	#endif
	};

	static const struct v4l2_subdev_video_ops mt9v011_video_ops = {
	.enum_fmt = mt9v011_enum_fmt,
	.try_fmt = mt9v011_try_fmt,
	.s_fmt = mt9v011_s_fmt,
	.g_parm = mt9v011_g_parm,
	.s_parm = mt9v011_s_parm,
	};

	static const struct v4l2_subdev_ops mt9v011_ops = {
	.core = &mt9v011_core_ops,
	.video = &mt9v011_video_ops,
	};


	/****************************************************************************
	I2C Client & Driver
	****************************************************************************/

	static int mt9v011_probe(struct i2c_client *c,
	const struct i2c_device_id *id)
	{
	u16 version;
	struct mt9v011 *core;
	struct v4l2_subdev *sd;

	/* Check if the adapter supports the needed features */
	if (!i2c_check_functionality(c->adapter,
	I2C_FUNC_SMBUS_READ_BYTE \| I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
	return -EIO;

	core = kzalloc(sizeof(struct mt9v011), GFP_KERNEL);
	if (!core)
	return -ENOMEM;

	sd = &core->sd;
	v4l2_i2c_subdev_init(sd, c, &mt9v011_ops);

	/* Check if the sensor is really a MT9V011 */
	version = mt9v011_read(sd, R00_MT9V011_CHIP_VERSION);
	if ((version != MT9V011_VERSION) &&
	(version != MT9V011_REV_B_VERSION)) {
	v4l2_info(sd, "*** unknown micron chip detected (0x%04x).\n",
	version);
	kfree(core);
	return -EINVAL;
	}

	core->global_gain = 0x0024;
	core->width = 640;
	core->height = 480;
	core->xtal = 27000000; /* Hz */

	v4l_info(c, "chip found @ 0x%02x (%s - chip version 0x%04x)\n",
	c->addr << 1, c->adapter->name, version);

	return 0;
	}

	static int mt9v011_remove(struct i2c_client *c)
	{
	struct v4l2_subdev *sd = i2c_get_clientdata(c);

	v4l2_dbg(1, debug, sd,
	"mt9v011.c: removing mt9v011 adapter on address 0x%x\n",
	c->addr << 1);

	v4l2_device_unregister_subdev(sd);
	kfree(to_mt9v011(sd));
	return 0;
	}

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

	static const struct i2c_device_id mt9v011_id[] = {
	{ "mt9v011", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, mt9v011_id);

	static struct v4l2_i2c_driver_data v4l2_i2c_data = {
	.name = "mt9v011",
	.probe = mt9v011_probe,
	.remove = mt9v011_remove,
	.id_table = mt9v011_id,
	};