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/*
 * drivers/media/video/tcm825x.c
 *
 * TCM825X camera sensor driver.
 *
 * Copyright (C) 2007 Nokia Corporation.
 *
 * Contact: Sakari Ailus <sakari.ailus@nokia.com>
 *
 * Based on code from David Cohen <david.cohen@indt.org.br>
 *
 * This driver was based on ov9640 sensor driver from MontaVista
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/i2c.h>
#include <linux/module.h>
#include <media/v4l2-int-device.h>

#include "tcm825x.h"

/*
 * The sensor has two fps modes: the lower one just gives half the fps
 * at the same xclk than the high one.
 */
#define MAX_FPS 30
#define MIN_FPS 8
#define MAX_HALF_FPS (MAX_FPS / 2)
#define HIGH_FPS_MODE_LOWER_LIMIT 14
#define DEFAULT_FPS MAX_HALF_FPS

struct tcm825x_sensor {
	const struct tcm825x_platform_data *platform_data;
	struct v4l2_int_device *v4l2_int_device;
	struct i2c_client *i2c_client;
	struct v4l2_pix_format pix;
	struct v4l2_fract timeperframe;
};

/* list of image formats supported by TCM825X sensor */
static const struct v4l2_fmtdesc tcm825x_formats[] = {
	{
		.description = "YUYV (YUV 4:2:2), packed",
		.pixelformat = V4L2_PIX_FMT_UYVY,
	}, {
		/* Note:  V4L2 defines RGB565 as:
		 *
		 *      Byte 0                    Byte 1
		 *      g2 g1 g0 r4 r3 r2 r1 r0   b4 b3 b2 b1 b0 g5 g4 g3
		 *
		 * We interpret RGB565 as:
		 *
		 *      Byte 0                    Byte 1
		 *      g2 g1 g0 b4 b3 b2 b1 b0   r4 r3 r2 r1 r0 g5 g4 g3
		 */
		.description = "RGB565, le",
		.pixelformat = V4L2_PIX_FMT_RGB565,
	},
};

#define TCM825X_NUM_CAPTURE_FORMATS	ARRAY_SIZE(tcm825x_formats)

/*
 * TCM825X register configuration for all combinations of pixel format and
 * image size
 */
static const struct tcm825x_reg subqcif	=	{ 0x20, TCM825X_PICSIZ };
static const struct tcm825x_reg qcif	=	{ 0x18, TCM825X_PICSIZ };
static const struct tcm825x_reg cif	=	{ 0x14, TCM825X_PICSIZ };
static const struct tcm825x_reg qqvga	=	{ 0x0c, TCM825X_PICSIZ };
static const struct tcm825x_reg qvga	=	{ 0x04, TCM825X_PICSIZ };
static const struct tcm825x_reg vga	=	{ 0x00, TCM825X_PICSIZ };

static const struct tcm825x_reg yuv422	=	{ 0x00, TCM825X_PICFMT };
static const struct tcm825x_reg rgb565	=	{ 0x02, TCM825X_PICFMT };

/* Our own specific controls */
#define V4L2_CID_ALC				V4L2_CID_PRIVATE_BASE
#define V4L2_CID_H_EDGE_EN			V4L2_CID_PRIVATE_BASE + 1
#define V4L2_CID_V_EDGE_EN			V4L2_CID_PRIVATE_BASE + 2
#define V4L2_CID_LENS				V4L2_CID_PRIVATE_BASE + 3
#define V4L2_CID_MAX_EXPOSURE_TIME		V4L2_CID_PRIVATE_BASE + 4
#define V4L2_CID_LAST_PRIV			V4L2_CID_MAX_EXPOSURE_TIME

/*  Video controls  */
static struct vcontrol {
	struct v4l2_queryctrl qc;
	u16 reg;
	u16 start_bit;
} video_control[] = {
	{
		{
			.id = V4L2_CID_GAIN,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "Gain",
			.minimum = 0,
			.maximum = 63,
			.step = 1,
		},
		.reg = TCM825X_AG,
		.start_bit = 0,
	},
	{
		{
			.id = V4L2_CID_RED_BALANCE,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "Red Balance",
			.minimum = 0,
			.maximum = 255,
			.step = 1,
		},
		.reg = TCM825X_MRG,
		.start_bit = 0,
	},
	{
		{
			.id = V4L2_CID_BLUE_BALANCE,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "Blue Balance",
			.minimum = 0,
			.maximum = 255,
			.step = 1,
		},
		.reg = TCM825X_MBG,
		.start_bit = 0,
	},
	{
		{
			.id = V4L2_CID_AUTO_WHITE_BALANCE,
			.type = V4L2_CTRL_TYPE_BOOLEAN,
			.name = "Auto White Balance",
			.minimum = 0,
			.maximum = 1,
			.step = 0,
		},
		.reg = TCM825X_AWBSW,
		.start_bit = 7,
	},
	{
		{
			.id = V4L2_CID_EXPOSURE,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "Exposure Time",
			.minimum = 0,
			.maximum = 0x1fff,
			.step = 1,
		},
		.reg = TCM825X_ESRSPD_U,
		.start_bit = 0,
	},
	{
		{
			.id = V4L2_CID_HFLIP,
			.type = V4L2_CTRL_TYPE_BOOLEAN,
			.name = "Mirror Image",
			.minimum = 0,
			.maximum = 1,
			.step = 0,
		},
		.reg = TCM825X_H_INV,
		.start_bit = 6,
	},
	{
		{
			.id = V4L2_CID_VFLIP,
			.type = V4L2_CTRL_TYPE_BOOLEAN,
			.name = "Vertical Flip",
			.minimum = 0,
			.maximum = 1,
			.step = 0,
		},
		.reg = TCM825X_V_INV,
		.start_bit = 7,
	},
	/* Private controls */
	{
		{
			.id = V4L2_CID_ALC,
			.type = V4L2_CTRL_TYPE_BOOLEAN,
			.name = "Auto Luminance Control",
			.minimum = 0,
			.maximum = 1,
			.step = 0,
		},
		.reg = TCM825X_ALCSW,
		.start_bit = 7,
	},
	{
		{
			.id = V4L2_CID_H_EDGE_EN,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "Horizontal Edge Enhancement",
			.minimum = 0,
			.maximum = 0xff,
			.step = 1,
		},
		.reg = TCM825X_HDTG,
		.start_bit = 0,
	},
	{
		{
			.id = V4L2_CID_V_EDGE_EN,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "Vertical Edge Enhancement",
			.minimum = 0,
			.maximum = 0xff,
			.step = 1,
		},
		.reg = TCM825X_VDTG,
		.start_bit = 0,
	},
	{
		{
			.id = V4L2_CID_LENS,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "Lens Shading Compensation",
			.minimum = 0,
			.maximum = 0x3f,
			.step = 1,
		},
		.reg = TCM825X_LENS,
		.start_bit = 0,
	},
	{
		{
			.id = V4L2_CID_MAX_EXPOSURE_TIME,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "Maximum Exposure Time",
			.minimum = 0,
			.maximum = 0x3,
			.step = 1,
		},
		.reg = TCM825X_ESRLIM,
		.start_bit = 5,
	},
};


static const struct tcm825x_reg *tcm825x_siz_reg[NUM_IMAGE_SIZES] =
{ &subqcif, &qqvga, &qcif, &qvga, &cif, &vga };

static const struct tcm825x_reg *tcm825x_fmt_reg[NUM_PIXEL_FORMATS] =
{ &yuv422, &rgb565 };

/*
 * Read a value from a register in an TCM825X sensor device.  The value is
 * returned in 'val'.
 * Returns zero if successful, or non-zero otherwise.
 */
static int tcm825x_read_reg(struct i2c_client *client, int reg)
{
	int err;
	struct i2c_msg msg[2];
	u8 reg_buf, data_buf = 0;

	if (!client->adapter)
		return -ENODEV;

	msg[0].addr = client->addr;
	msg[0].flags = 0;
	msg[0].len = 1;
	msg[0].buf = &reg_buf;
	msg[1].addr = client->addr;
	msg[1].flags = I2C_M_RD;
	msg[1].len = 1;
	msg[1].buf = &data_buf;

	reg_buf = reg;

	err = i2c_transfer(client->adapter, msg, 2);
	if (err < 0)
		return err;
	return data_buf;
}

/*
 * Write a value to a register in an TCM825X sensor device.
 * Returns zero if successful, or non-zero otherwise.
 */
static int tcm825x_write_reg(struct i2c_client *client, u8 reg, u8 val)
{
	int err;
	struct i2c_msg msg[1];
	unsigned char data[2];

	if (!client->adapter)
		return -ENODEV;

	msg->addr = client->addr;
	msg->flags = 0;
	msg->len = 2;
	msg->buf = data;
	data[0] = reg;
	data[1] = val;
	err = i2c_transfer(client->adapter, msg, 1);
	if (err >= 0)
		return 0;
	return err;
}

static int __tcm825x_write_reg_mask(struct i2c_client *client,
				    u8 reg, u8 val, u8 mask)
{
	int rc;

	/* need to do read - modify - write */
	rc = tcm825x_read_reg(client, reg);
	if (rc < 0)
		return rc;

	rc &= (~mask);	/* Clear the masked bits */
	val &= mask;	/* Enforce mask on value */
	val |= rc;

	/* write the new value to the register */
	rc = tcm825x_write_reg(client, reg, val);
	if (rc)
		return rc;

	return 0;
}

#define tcm825x_write_reg_mask(client, regmask, val)			\
	__tcm825x_write_reg_mask(client, TCM825X_ADDR((regmask)), val,	\
				 TCM825X_MASK((regmask)))


/*
 * Initialize a list of TCM825X registers.
 * The list of registers is terminated by the pair of values
 * { TCM825X_REG_TERM, TCM825X_VAL_TERM }.
 * Returns zero if successful, or non-zero otherwise.
 */
static int tcm825x_write_default_regs(struct i2c_client *client,
				      const struct tcm825x_reg *reglist)
{
	int err;
	const struct tcm825x_reg *next = reglist;

	while (!((next->reg == TCM825X_REG_TERM)
		 && (next->val == TCM825X_VAL_TERM))) {
		err = tcm825x_write_reg(client, next->reg, next->val);
		if (err) {
			dev_err(&client->dev, "register writing failed\n");
			return err;
		}
		next++;
	}

	return 0;
}

static struct vcontrol *find_vctrl(int id)
{
	int i;

	if (id < V4L2_CID_BASE)
		return NULL;

	for (i = 0; i < ARRAY_SIZE(video_control); i++)
		if (video_control[i].qc.id == id)
			return &video_control[i];

	return NULL;
}

/*
 * Find the best match for a requested image capture size.  The best match
 * is chosen as the nearest match that has the same number or fewer pixels
 * as the requested size, or the smallest image size if the requested size
 * has fewer pixels than the smallest image.
 */
static enum image_size tcm825x_find_size(struct v4l2_int_device *s,
					 unsigned int width,
					 unsigned int height)
{
	enum image_size isize;
	unsigned long pixels = width * height;
	struct tcm825x_sensor *sensor = s->priv;

	for (isize = subQCIF; isize < VGA; isize++) {
		if (tcm825x_sizes[isize + 1].height
		    * tcm825x_sizes[isize + 1].width > pixels) {
			dev_dbg(&sensor->i2c_client->dev, "size %d\n", isize);

			return isize;
		}
	}

	dev_dbg(&sensor->i2c_client->dev, "format default VGA\n");

	return VGA;
}

/*
 * Configure the TCM825X for current image size, pixel format, and
 * frame period. fper is the frame period (in seconds) expressed as a
 * fraction. Returns zero if successful, or non-zero otherwise. The
 * actual frame period is returned in fper.
 */
static int tcm825x_configure(struct v4l2_int_device *s)
{
	struct tcm825x_sensor *sensor = s->priv;
	struct v4l2_pix_format *pix = &sensor->pix;
	enum image_size isize = tcm825x_find_size(s, pix->width, pix->height);
	struct v4l2_fract *fper = &sensor->timeperframe;
	enum pixel_format pfmt;
	int err;
	u32 tgt_fps;
	u8 val;

	/* common register initialization */
	err = tcm825x_write_default_regs(
		sensor->i2c_client, sensor->platform_data->default_regs());
	if (err)
		return err;

	/* configure image size */
	val = tcm825x_siz_reg[isize]->val;
	dev_dbg(&sensor->i2c_client->dev,
		"configuring image size %d\n", isize);
	err = tcm825x_write_reg_mask(sensor->i2c_client,
				     tcm825x_siz_reg[isize]->reg, val);
	if (err)
		return err;

	/* configure pixel format */
	switch (pix->pixelformat) {
	default:
	case V4L2_PIX_FMT_RGB565:
		pfmt = RGB565;
		break;
	case V4L2_PIX_FMT_UYVY:
		pfmt = YUV422;
		break;
	}

	dev_dbg(&sensor->i2c_client->dev,
		"configuring pixel format %d\n", pfmt);
	val = tcm825x_fmt_reg[pfmt]->val;

	err = tcm825x_write_reg_mask(sensor->i2c_client,
				     tcm825x_fmt_reg[pfmt]->reg, val);
	if (err)
		return err;

	/*
	 * For frame rate < 15, the FPS reg (addr 0x02, bit 7) must be
	 * set. Frame rate will be halved from the normal.
	 */
	tgt_fps = fper->denominator / fper->numerator;
	if (tgt_fps <= HIGH_FPS_MODE_LOWER_LIMIT) {
		val = tcm825x_read_reg(sensor->i2c_client, 0x02);
		val |= 0x80;
		tcm825x_write_reg(sensor->i2c_client, 0x02, val);
	}

	return 0;
}

static int ioctl_queryctrl(struct v4l2_int_device *s,
				struct v4l2_queryctrl *qc)
{
	struct vcontrol *control;

	control = find_vctrl(qc->id);

	if (control == NULL)
		return -EINVAL;

	*qc = control->qc;

	return 0;
}

static int ioctl_g_ctrl(struct v4l2_int_device *s,
			     struct v4l2_control *vc)
{
	struct tcm825x_sensor *sensor = s->priv;
	struct i2c_client *client = sensor->i2c_client;
	int val, r;
	struct vcontrol *lvc;

	/* exposure time is special, spread across 2 registers */
	if (vc->id == V4L2_CID_EXPOSURE) {
		int val_lower, val_upper;

		val_upper = tcm825x_read_reg(client,
					     TCM825X_ADDR(TCM825X_ESRSPD_U));
		if (val_upper < 0)
			return val_upper;
		val_lower = tcm825x_read_reg(client,
					     TCM825X_ADDR(TCM825X_ESRSPD_L));
		if (val_lower < 0)
			return val_lower;

		vc->value = ((val_upper & 0x1f) << 8) | (val_lower);
		return 0;
	}

	lvc = find_vctrl(vc->id);
	if (lvc == NULL)
		return -EINVAL;

	r = tcm825x_read_reg(client, TCM825X_ADDR(lvc->reg));
	if (r < 0)
		return r;
	val = r & TCM825X_MASK(lvc->reg);
	val >>= lvc->start_bit;

	if (val < 0)
		return val;

	if (vc->id == V4L2_CID_HFLIP || vc->id == V4L2_CID_VFLIP)
		val ^= sensor->platform_data->is_upside_down();

	vc->value = val;
	return 0;
}

static int ioctl_s_ctrl(struct v4l2_int_device *s,
			     struct v4l2_control *vc)
{
	struct tcm825x_sensor *sensor = s->priv;
	struct i2c_client *client = sensor->i2c_client;
	struct vcontrol *lvc;
	int val = vc->value;

	/* exposure time is special, spread across 2 registers */
	if (vc->id == V4L2_CID_EXPOSURE) {
		int val_lower, val_upper;
		val_lower = val & TCM825X_MASK(TCM825X_ESRSPD_L);
		val_upper = (val >> 8) & TCM825X_MASK(TCM825X_ESRSPD_U);

		if (tcm825x_write_reg_mask(client,
					   TCM825X_ESRSPD_U, val_upper))
			return -EIO;

		if (tcm825x_write_reg_mask(client,
					   TCM825X_ESRSPD_L, val_lower))
			return -EIO;

		return 0;
	}

	lvc = find_vctrl(vc->id);
	if (lvc == NULL)
		return -EINVAL;

	if (vc->id == V4L2_CID_HFLIP || vc->id == V4L2_CID_VFLIP)
		val ^= sensor->platform_data->is_upside_down();

	val = val << lvc->start_bit;
	if (tcm825x_write_reg_mask(client, lvc->reg, val))
		return -EIO;

	return 0;
}

static int ioctl_enum_fmt_cap(struct v4l2_int_device *s,
				   struct v4l2_fmtdesc *fmt)
{
	int index = fmt->index;

	switch (fmt->type) {
	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
		if (index >= TCM825X_NUM_CAPTURE_FORMATS)
			return -EINVAL;
		break;

	default:
		return -EINVAL;
	}

	fmt->flags = tcm825x_formats[index].flags;
	strlcpy(fmt->description, tcm825x_formats[index].description,
		sizeof(fmt->description));
	fmt->pixelformat = tcm825x_formats[index].pixelformat;

	return 0;
}

static int ioctl_try_fmt_cap(struct v4l2_int_device *s,
			     struct v4l2_format *f)
{
	struct tcm825x_sensor *sensor = s->priv;
	enum image_size isize;
	int ifmt;
	struct v4l2_pix_format *pix = &f->fmt.pix;

	isize = tcm825x_find_size(s, pix->width, pix->height);
	dev_dbg(&sensor->i2c_client->dev, "isize = %d num_capture = %lu\n",
		isize, (unsigned long)TCM825X_NUM_CAPTURE_FORMATS);

	pix->width = tcm825x_sizes[isize].width;
	pix->height = tcm825x_sizes[isize].height;

	for (ifmt = 0; ifmt < TCM825X_NUM_CAPTURE_FORMATS; ifmt++)
		if (pix->pixelformat == tcm825x_formats[ifmt].pixelformat)
			break;

	if (ifmt == TCM825X_NUM_CAPTURE_FORMATS)
		ifmt = 0;	/* Default = YUV 4:2:2 */

	pix->pixelformat = tcm825x_formats[ifmt].pixelformat;
	pix->field = V4L2_FIELD_NONE;
	pix->bytesperline = pix->width * TCM825X_BYTES_PER_PIXEL;
	pix->sizeimage = pix->bytesperline * pix->height;
	pix->priv = 0;
	dev_dbg(&sensor->i2c_client->dev, "format = 0x%08x\n",
		pix->pixelformat);

	switch (pix->pixelformat) {
	case V4L2_PIX_FMT_UYVY:
	default:
		pix->colorspace = V4L2_COLORSPACE_JPEG;
		break;
	case V4L2_PIX_FMT_RGB565:
		pix->colorspace = V4L2_COLORSPACE_SRGB;
		break;
	}

	return 0;
}

static int ioctl_s_fmt_cap(struct v4l2_int_device *s,
				struct v4l2_format *f)
{
	struct tcm825x_sensor *sensor = s->priv;
	struct v4l2_pix_format *pix = &f->fmt.pix;
	int rval;

	rval = ioctl_try_fmt_cap(s, f);
	if (rval)
		return rval;

	rval = tcm825x_configure(s);

	sensor->pix = *pix;

	return rval;
}

static int ioctl_g_fmt_cap(struct v4l2_int_device *s,
				struct v4l2_format *f)
{
	struct tcm825x_sensor *sensor = s->priv;

	f->fmt.pix = sensor->pix;

	return 0;
}

static int ioctl_g_parm(struct v4l2_int_device *s,
			     struct v4l2_streamparm *a)
{
	struct tcm825x_sensor *sensor = s->priv;
	struct v4l2_captureparm *cparm = &a->parm.capture;

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

	memset(a, 0, sizeof(*a));
	a->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

	cparm->capability = V4L2_CAP_TIMEPERFRAME;
	cparm->timeperframe = sensor->timeperframe;

	return 0;
}

static int ioctl_s_parm(struct v4l2_int_device *s,
			     struct v4l2_streamparm *a)
{
	struct tcm825x_sensor *sensor = s->priv;
	struct v4l2_fract *timeperframe = &a->parm.capture.timeperframe;
	u32 tgt_fps;	/* target frames per secound */
	int rval;

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

	if ((timeperframe->numerator == 0)
	    || (timeperframe->denominator == 0)) {
		timeperframe->denominator = DEFAULT_FPS;
		timeperframe->numerator = 1;
	}

	tgt_fps = timeperframe->denominator / timeperframe->numerator;

	if (tgt_fps > MAX_FPS) {
		timeperframe->denominator = MAX_FPS;
		timeperframe->numerator = 1;
	} else if (tgt_fps < MIN_FPS) {
		timeperframe->denominator = MIN_FPS;
		timeperframe->numerator = 1;
	}

	sensor->timeperframe = *timeperframe;

	rval = tcm825x_configure(s);

	return rval;
}

static int ioctl_s_power(struct v4l2_int_device *s, int on)
{
	struct tcm825x_sensor *sensor = s->priv;

	return sensor->platform_data->power_set(on);
}

/*
 * Given the image capture format in pix, the nominal frame period in
 * timeperframe, calculate the required xclk frequency.
 *
 * TCM825X input frequency characteristics are:
 *     Minimum 11.9 MHz, Typical 24.57 MHz and maximum 25/27 MHz
 */

static int ioctl_g_ifparm(struct v4l2_int_device *s, struct v4l2_ifparm *p)
{
	struct tcm825x_sensor *sensor = s->priv;
	struct v4l2_fract *timeperframe = &sensor->timeperframe;
	u32 tgt_xclk;	/* target xclk */
	u32 tgt_fps;	/* target frames per secound */
	int rval;

	rval = sensor->platform_data->ifparm(p);
	if (rval)
		return rval;

	tgt_fps = timeperframe->denominator / timeperframe->numerator;

	tgt_xclk = (tgt_fps <= HIGH_FPS_MODE_LOWER_LIMIT) ?
		(2457 * tgt_fps) / MAX_HALF_FPS :
		(2457 * tgt_fps) / MAX_FPS;
	tgt_xclk *= 10000;

	tgt_xclk = min(tgt_xclk, (u32)TCM825X_XCLK_MAX);
	tgt_xclk = max(tgt_xclk, (u32)TCM825X_XCLK_MIN);

	p->u.bt656.clock_curr = tgt_xclk;

	return 0;
}

static int ioctl_g_needs_reset(struct v4l2_int_device *s, void *buf)
{
	struct tcm825x_sensor *sensor = s->priv;

	return sensor->platform_data->needs_reset(s, buf, &sensor->pix);
}

static int ioctl_reset(struct v4l2_int_device *s)
{
	return -EBUSY;
}

static int ioctl_init(struct v4l2_int_device *s)
{
	return tcm825x_configure(s);
}

static int ioctl_dev_exit(struct v4l2_int_device *s)
{
	return 0;
}

static int ioctl_dev_init(struct v4l2_int_device *s)
{
	struct tcm825x_sensor *sensor = s->priv;
	int r;

	r = tcm825x_read_reg(sensor->i2c_client, 0x01);
	if (r < 0)
		return r;
	if (r == 0) {
		dev_err(&sensor->i2c_client->dev, "device not detected\n");
		return -EIO;
	}
	return 0;
}

static struct v4l2_int_ioctl_desc tcm825x_ioctl_desc[] = {
	{ vidioc_int_dev_init_num,
	  (v4l2_int_ioctl_func *)ioctl_dev_init },
	{ vidioc_int_dev_exit_num,
	  (v4l2_int_ioctl_func *)ioctl_dev_exit },
	{ vidioc_int_s_power_num,
	  (v4l2_int_ioctl_func *)ioctl_s_power },
	{ vidioc_int_g_ifparm_num,
	  (v4l2_int_ioctl_func *)ioctl_g_ifparm },
	{ vidioc_int_g_needs_reset_num,
	  (v4l2_int_ioctl_func *)ioctl_g_needs_reset },
	{ vidioc_int_reset_num,
	  (v4l2_int_ioctl_func *)ioctl_reset },
	{ vidioc_int_init_num,
	  (v4l2_int_ioctl_func *)ioctl_init },
	{ vidioc_int_enum_fmt_cap_num,
	  (v4l2_int_ioctl_func *)ioctl_enum_fmt_cap },
	{ vidioc_int_try_fmt_cap_num,
	  (v4l2_int_ioctl_func *)ioctl_try_fmt_cap },
	{ vidioc_int_g_fmt_cap_num,
	  (v4l2_int_ioctl_func *)ioctl_g_fmt_cap },
	{ vidioc_int_s_fmt_cap_num,
	  (v4l2_int_ioctl_func *)ioctl_s_fmt_cap },
	{ vidioc_int_g_parm_num,
	  (v4l2_int_ioctl_func *)ioctl_g_parm },
	{ vidioc_int_s_parm_num,
	  (v4l2_int_ioctl_func *)ioctl_s_parm },
	{ vidioc_int_queryctrl_num,
	  (v4l2_int_ioctl_func *)ioctl_queryctrl },
	{ vidioc_int_g_ctrl_num,
	  (v4l2_int_ioctl_func *)ioctl_g_ctrl },
	{ vidioc_int_s_ctrl_num,
	  (v4l2_int_ioctl_func *)ioctl_s_ctrl },
};

static struct v4l2_int_slave tcm825x_slave = {
	.ioctls = tcm825x_ioctl_desc,
	.num_ioctls = ARRAY_SIZE(tcm825x_ioctl_desc),
};

static struct tcm825x_sensor tcm825x;

static struct v4l2_int_device tcm825x_int_device = {
	.module = THIS_MODULE,
	.name = TCM825X_NAME,
	.priv = &tcm825x,
	.type = v4l2_int_type_slave,
	.u = {
		.slave = &tcm825x_slave,
	},
};

static int tcm825x_probe(struct i2c_client *client,
			 const struct i2c_device_id *did)
{
	struct tcm825x_sensor *sensor = &tcm825x;

	if (i2c_get_clientdata(client))
		return -EBUSY;

	sensor->platform_data = client->dev.platform_data;

	if (sensor->platform_data == NULL
	    || !sensor->platform_data->is_okay())
		return -ENODEV;

	sensor->v4l2_int_device = &tcm825x_int_device;

	sensor->i2c_client = client;
	i2c_set_clientdata(client, sensor);

	/* Make the default capture format QVGA RGB565 */
	sensor->pix.width = tcm825x_sizes[QVGA].width;
	sensor->pix.height = tcm825x_sizes[QVGA].height;
	sensor->pix.pixelformat = V4L2_PIX_FMT_RGB565;

	return v4l2_int_device_register(sensor->v4l2_int_device);
}

static int tcm825x_remove(struct i2c_client *client)
{
	struct tcm825x_sensor *sensor = i2c_get_clientdata(client);

	if (!client->adapter)
		return -ENODEV;	/* our client isn't attached */

	v4l2_int_device_unregister(sensor->v4l2_int_device);

	return 0;
}

static const struct i2c_device_id tcm825x_id[] = {
	{ "tcm825x", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tcm825x_id);

static struct i2c_driver tcm825x_i2c_driver = {
	.driver	= {
		.name = TCM825X_NAME,
	},
	.probe	= tcm825x_probe,
	.remove	= tcm825x_remove,
	.id_table = tcm825x_id,
};

static struct tcm825x_sensor tcm825x = {
	.timeperframe = {
		.numerator   = 1,
		.denominator = DEFAULT_FPS,
	},
};

static int __init tcm825x_init(void)
{
	int rval;

	rval = i2c_add_driver(&tcm825x_i2c_driver);
	if (rval)
		printk(KERN_INFO "%s: failed registering " TCM825X_NAME "\n",
		       __func__);

	return rval;
}

static void __exit tcm825x_exit(void)
{
	i2c_del_driver(&tcm825x_i2c_driver);
}

/*
 * FIXME: Menelaus isn't ready (?) at module_init stage, so use
 * late_initcall for now.
 */
late_initcall(tcm825x_init);
module_exit(tcm825x_exit);

MODULE_AUTHOR("Sakari Ailus <sakari.ailus@nokia.com>");
MODULE_DESCRIPTION("TCM825x camera sensor driver");
MODULE_LICENSE("GPL");