Merge remote-tracking branch 'master' into queue

Merge reason: development work has dependency on kvm patches merged
upstream.

Conflicts:
	arch/powerpc/include/asm/Kbuild
	arch/powerpc/include/asm/kvm_para.h

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 857 insertions, 0 deletions

diff --git a/drivers/media/i2c/soc_camera/mt9t031.c b/drivers/media/i2c/soc_camera/mt9t031.c
new file mode 100644
index 000000000000..40800b10a080
--- /dev/null
+++ b/drivers/media/i2c/soc_camera/mt9t031.c
@@ -0,0 +1,857 @@
+/*
+ * Driver for MT9T031 CMOS Image Sensor from Micron
+ *
+ * Copyright (C) 2008, Guennadi Liakhovetski, DENX Software Engineering <lg@denx.de>
+ *
+ * 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.
+ */
+
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/log2.h>
+#include <linux/pm.h>
+#include <linux/slab.h>
+#include <linux/v4l2-mediabus.h>
+#include <linux/videodev2.h>
+#include <linux/module.h>
+
+#include <media/soc_camera.h>
+#include <media/v4l2-chip-ident.h>
+#include <media/v4l2-subdev.h>
+#include <media/v4l2-ctrls.h>
+
+/*
+ * ATTENTION: this driver still cannot be used outside of the soc-camera
+ * framework because of its PM implementation, using the video_device node.
+ * If hardware becomes available for testing, alternative PM approaches shall
+ * be considered and tested.
+ */
+
+/*
+ * mt9t031 i2c address 0x5d
+ * The platform has to define i2c_board_info and link to it from
+ * struct soc_camera_link
+ */
+
+/* mt9t031 selected register addresses */
+#define MT9T031_CHIP_VERSION		0x00
+#define MT9T031_ROW_START		0x01
+#define MT9T031_COLUMN_START		0x02
+#define MT9T031_WINDOW_HEIGHT		0x03
+#define MT9T031_WINDOW_WIDTH		0x04
+#define MT9T031_HORIZONTAL_BLANKING	0x05
+#define MT9T031_VERTICAL_BLANKING	0x06
+#define MT9T031_OUTPUT_CONTROL		0x07
+#define MT9T031_SHUTTER_WIDTH_UPPER	0x08
+#define MT9T031_SHUTTER_WIDTH		0x09
+#define MT9T031_PIXEL_CLOCK_CONTROL	0x0a
+#define MT9T031_FRAME_RESTART		0x0b
+#define MT9T031_SHUTTER_DELAY		0x0c
+#define MT9T031_RESET			0x0d
+#define MT9T031_READ_MODE_1		0x1e
+#define MT9T031_READ_MODE_2		0x20
+#define MT9T031_READ_MODE_3		0x21
+#define MT9T031_ROW_ADDRESS_MODE	0x22
+#define MT9T031_COLUMN_ADDRESS_MODE	0x23
+#define MT9T031_GLOBAL_GAIN		0x35
+#define MT9T031_CHIP_ENABLE		0xF8
+
+#define MT9T031_MAX_HEIGHT		1536
+#define MT9T031_MAX_WIDTH		2048
+#define MT9T031_MIN_HEIGHT		2
+#define MT9T031_MIN_WIDTH		18
+#define MT9T031_HORIZONTAL_BLANK	142
+#define MT9T031_VERTICAL_BLANK		25
+#define MT9T031_COLUMN_SKIP		32
+#define MT9T031_ROW_SKIP		20
+
+struct mt9t031 {
+	struct v4l2_subdev subdev;
+	struct v4l2_ctrl_handler hdl;
+	struct {
+		/* exposure/auto-exposure cluster */
+		struct v4l2_ctrl *autoexposure;
+		struct v4l2_ctrl *exposure;
+	};
+	struct v4l2_rect rect;	/* Sensor window */
+	int model;	/* V4L2_IDENT_MT9T031* codes from v4l2-chip-ident.h */
+	u16 xskip;
+	u16 yskip;
+	unsigned int total_h;
+	unsigned short y_skip_top;	/* Lines to skip at the top */
+};
+
+static struct mt9t031 *to_mt9t031(const struct i2c_client *client)
+{
+	return container_of(i2c_get_clientdata(client), struct mt9t031, subdev);
+}
+
+static int reg_read(struct i2c_client *client, const u8 reg)
+{
+	return i2c_smbus_read_word_swapped(client, reg);
+}
+
+static int reg_write(struct i2c_client *client, const u8 reg,
+		     const u16 data)
+{
+	return i2c_smbus_write_word_swapped(client, reg, data);
+}
+
+static int reg_set(struct i2c_client *client, const u8 reg,
+		   const u16 data)
+{
+	int ret;
+
+	ret = reg_read(client, reg);
+	if (ret < 0)
+		return ret;
+	return reg_write(client, reg, ret | data);
+}
+
+static int reg_clear(struct i2c_client *client, const u8 reg,
+		     const u16 data)
+{
+	int ret;
+
+	ret = reg_read(client, reg);
+	if (ret < 0)
+		return ret;
+	return reg_write(client, reg, ret & ~data);
+}
+
+static int set_shutter(struct i2c_client *client, const u32 data)
+{
+	int ret;
+
+	ret = reg_write(client, MT9T031_SHUTTER_WIDTH_UPPER, data >> 16);
+
+	if (ret >= 0)
+		ret = reg_write(client, MT9T031_SHUTTER_WIDTH, data & 0xffff);
+
+	return ret;
+}
+
+static int get_shutter(struct i2c_client *client, u32 *data)
+{
+	int ret;
+
+	ret = reg_read(client, MT9T031_SHUTTER_WIDTH_UPPER);
+	*data = ret << 16;
+
+	if (ret >= 0)
+		ret = reg_read(client, MT9T031_SHUTTER_WIDTH);
+	*data |= ret & 0xffff;
+
+	return ret < 0 ? ret : 0;
+}
+
+static int mt9t031_idle(struct i2c_client *client)
+{
+	int ret;
+
+	/* Disable chip output, synchronous option update */
+	ret = reg_write(client, MT9T031_RESET, 1);
+	if (ret >= 0)
+		ret = reg_write(client, MT9T031_RESET, 0);
+	if (ret >= 0)
+		ret = reg_clear(client, MT9T031_OUTPUT_CONTROL, 2);
+
+	return ret >= 0 ? 0 : -EIO;
+}
+
+static int mt9t031_s_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	int ret;
+
+	if (enable)
+		/* Switch to master "normal" mode */
+		ret = reg_set(client, MT9T031_OUTPUT_CONTROL, 2);
+	else
+		/* Stop sensor readout */
+		ret = reg_clear(client, MT9T031_OUTPUT_CONTROL, 2);
+
+	if (ret < 0)
+		return -EIO;
+
+	return 0;
+}
+
+/* target must be _even_ */
+static u16 mt9t031_skip(s32 *source, s32 target, s32 max)
+{
+	unsigned int skip;
+
+	if (*source < target + target / 2) {
+		*source = target;
+		return 1;
+	}
+
+	skip = min(max, *source + target / 2) / target;
+	if (skip > 8)
+		skip = 8;
+	*source = target * skip;
+
+	return skip;
+}
+
+/* rect is the sensor rectangle, the caller guarantees parameter validity */
+static int mt9t031_set_params(struct i2c_client *client,
+			      struct v4l2_rect *rect, u16 xskip, u16 yskip)
+{
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+	int ret;
+	u16 xbin, ybin;
+	const u16 hblank = MT9T031_HORIZONTAL_BLANK,
+		vblank = MT9T031_VERTICAL_BLANK;
+
+	xbin = min(xskip, (u16)3);
+	ybin = min(yskip, (u16)3);
+
+	/*
+	 * Could just do roundup(rect->left, [xy]bin * 2); but this is cheaper.
+	 * There is always a valid suitably aligned value. The worst case is
+	 * xbin = 3, width = 2048. Then we will start at 36, the last read out
+	 * pixel will be 2083, which is < 2085 - first black pixel.
+	 *
+	 * MT9T031 datasheet imposes window left border alignment, depending on
+	 * the selected xskip. Failing to conform to this requirement produces
+	 * dark horizontal stripes in the image. However, even obeying to this
+	 * requirement doesn't eliminate the stripes in all configurations. They
+	 * appear "locally reproducibly," but can differ between tests under
+	 * different lighting conditions.
+	 */
+	switch (xbin) {
+	case 1:
+		rect->left &= ~1;
+		break;
+	case 2:
+		rect->left &= ~3;
+		break;
+	case 3:
+		rect->left = rect->left > roundup(MT9T031_COLUMN_SKIP, 6) ?
+			(rect->left / 6) * 6 : roundup(MT9T031_COLUMN_SKIP, 6);
+	}
+
+	rect->top &= ~1;
+
+	dev_dbg(&client->dev, "skip %u:%u, rect %ux%u@%u:%u\n",
+		xskip, yskip, rect->width, rect->height, rect->left, rect->top);
+
+	/* Disable register update, reconfigure atomically */
+	ret = reg_set(client, MT9T031_OUTPUT_CONTROL, 1);
+	if (ret < 0)
+		return ret;
+
+	/* Blanking and start values - default... */
+	ret = reg_write(client, MT9T031_HORIZONTAL_BLANKING, hblank);
+	if (ret >= 0)
+		ret = reg_write(client, MT9T031_VERTICAL_BLANKING, vblank);
+
+	if (yskip != mt9t031->yskip || xskip != mt9t031->xskip) {
+		/* Binning, skipping */
+		if (ret >= 0)
+			ret = reg_write(client, MT9T031_COLUMN_ADDRESS_MODE,
+					((xbin - 1) << 4) | (xskip - 1));
+		if (ret >= 0)
+			ret = reg_write(client, MT9T031_ROW_ADDRESS_MODE,
+					((ybin - 1) << 4) | (yskip - 1));
+	}
+	dev_dbg(&client->dev, "new physical left %u, top %u\n",
+		rect->left, rect->top);
+
+	/*
+	 * The caller provides a supported format, as guaranteed by
+	 * .try_mbus_fmt(), soc_camera_s_crop() and soc_camera_cropcap()
+	 */
+	if (ret >= 0)
+		ret = reg_write(client, MT9T031_COLUMN_START, rect->left);
+	if (ret >= 0)
+		ret = reg_write(client, MT9T031_ROW_START, rect->top);
+	if (ret >= 0)
+		ret = reg_write(client, MT9T031_WINDOW_WIDTH, rect->width - 1);
+	if (ret >= 0)
+		ret = reg_write(client, MT9T031_WINDOW_HEIGHT,
+				rect->height + mt9t031->y_skip_top - 1);
+	if (ret >= 0 && v4l2_ctrl_g_ctrl(mt9t031->autoexposure) == V4L2_EXPOSURE_AUTO) {
+		mt9t031->total_h = rect->height + mt9t031->y_skip_top + vblank;
+
+		ret = set_shutter(client, mt9t031->total_h);
+	}
+
+	/* Re-enable register update, commit all changes */
+	if (ret >= 0)
+		ret = reg_clear(client, MT9T031_OUTPUT_CONTROL, 1);
+
+	if (ret >= 0) {
+		mt9t031->rect = *rect;
+		mt9t031->xskip = xskip;
+		mt9t031->yskip = yskip;
+	}
+
+	return ret < 0 ? ret : 0;
+}
+
+static int mt9t031_s_crop(struct v4l2_subdev *sd, const struct v4l2_crop *a)
+{
+	struct v4l2_rect rect = a->c;
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+
+	rect.width = ALIGN(rect.width, 2);
+	rect.height = ALIGN(rect.height, 2);
+
+	soc_camera_limit_side(&rect.left, &rect.width,
+		     MT9T031_COLUMN_SKIP, MT9T031_MIN_WIDTH, MT9T031_MAX_WIDTH);
+
+	soc_camera_limit_side(&rect.top, &rect.height,
+		     MT9T031_ROW_SKIP, MT9T031_MIN_HEIGHT, MT9T031_MAX_HEIGHT);
+
+	return mt9t031_set_params(client, &rect, mt9t031->xskip, mt9t031->yskip);
+}
+
+static int mt9t031_g_crop(struct v4l2_subdev *sd, struct v4l2_crop *a)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+
+	a->c	= mt9t031->rect;
+	a->type	= V4L2_BUF_TYPE_VIDEO_CAPTURE;
+
+	return 0;
+}
+
+static int mt9t031_cropcap(struct v4l2_subdev *sd, struct v4l2_cropcap *a)
+{
+	a->bounds.left			= MT9T031_COLUMN_SKIP;
+	a->bounds.top			= MT9T031_ROW_SKIP;
+	a->bounds.width			= MT9T031_MAX_WIDTH;
+	a->bounds.height		= MT9T031_MAX_HEIGHT;
+	a->defrect			= a->bounds;
+	a->type				= V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	a->pixelaspect.numerator	= 1;
+	a->pixelaspect.denominator	= 1;
+
+	return 0;
+}
+
+static int mt9t031_g_fmt(struct v4l2_subdev *sd,
+			 struct v4l2_mbus_framefmt *mf)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+
+	mf->width	= mt9t031->rect.width / mt9t031->xskip;
+	mf->height	= mt9t031->rect.height / mt9t031->yskip;
+	mf->code	= V4L2_MBUS_FMT_SBGGR10_1X10;
+	mf->colorspace	= V4L2_COLORSPACE_SRGB;
+	mf->field	= V4L2_FIELD_NONE;
+
+	return 0;
+}
+
+static int mt9t031_s_fmt(struct v4l2_subdev *sd,
+			 struct v4l2_mbus_framefmt *mf)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+	u16 xskip, yskip;
+	struct v4l2_rect rect = mt9t031->rect;
+
+	/*
+	 * try_fmt has put width and height within limits.
+	 * S_FMT: use binning and skipping for scaling
+	 */
+	xskip = mt9t031_skip(&rect.width, mf->width, MT9T031_MAX_WIDTH);
+	yskip = mt9t031_skip(&rect.height, mf->height, MT9T031_MAX_HEIGHT);
+
+	mf->code	= V4L2_MBUS_FMT_SBGGR10_1X10;
+	mf->colorspace	= V4L2_COLORSPACE_SRGB;
+
+	/* mt9t031_set_params() doesn't change width and height */
+	return mt9t031_set_params(client, &rect, xskip, yskip);
+}
+
+/*
+ * If a user window larger than sensor window is requested, we'll increase the
+ * sensor window.
+ */
+static int mt9t031_try_fmt(struct v4l2_subdev *sd,
+			   struct v4l2_mbus_framefmt *mf)
+{
+	v4l_bound_align_image(
+		&mf->width, MT9T031_MIN_WIDTH, MT9T031_MAX_WIDTH, 1,
+		&mf->height, MT9T031_MIN_HEIGHT, MT9T031_MAX_HEIGHT, 1, 0);
+
+	mf->code	= V4L2_MBUS_FMT_SBGGR10_1X10;
+	mf->colorspace	= V4L2_COLORSPACE_SRGB;
+
+	return 0;
+}
+
+static int mt9t031_g_chip_ident(struct v4l2_subdev *sd,
+				struct v4l2_dbg_chip_ident *id)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+
+	if (id->match.type != V4L2_CHIP_MATCH_I2C_ADDR)
+		return -EINVAL;
+
+	if (id->match.addr != client->addr)
+		return -ENODEV;
+
+	id->ident	= mt9t031->model;
+	id->revision	= 0;
+
+	return 0;
+}
+
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+static int mt9t031_g_register(struct v4l2_subdev *sd,
+			      struct v4l2_dbg_register *reg)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+
+	if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
+		return -EINVAL;
+
+	if (reg->match.addr != client->addr)
+		return -ENODEV;
+
+	reg->val = reg_read(client, reg->reg);
+
+	if (reg->val > 0xffff)
+		return -EIO;
+
+	return 0;
+}
+
+static int mt9t031_s_register(struct v4l2_subdev *sd,
+			      struct v4l2_dbg_register *reg)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+
+	if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
+		return -EINVAL;
+
+	if (reg->match.addr != client->addr)
+		return -ENODEV;
+
+	if (reg_write(client, reg->reg, reg->val) < 0)
+		return -EIO;
+
+	return 0;
+}
+#endif
+
+static int mt9t031_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct mt9t031 *mt9t031 = container_of(ctrl->handler,
+					       struct mt9t031, hdl);
+	const u32 shutter_max = MT9T031_MAX_HEIGHT + MT9T031_VERTICAL_BLANK;
+	s32 min, max;
+
+	switch (ctrl->id) {
+	case V4L2_CID_EXPOSURE_AUTO:
+		min = mt9t031->exposure->minimum;
+		max = mt9t031->exposure->maximum;
+		mt9t031->exposure->val =
+			(shutter_max / 2 + (mt9t031->total_h - 1) * (max - min))
+				/ shutter_max + min;
+		break;
+	}
+	return 0;
+}
+
+static int mt9t031_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct mt9t031 *mt9t031 = container_of(ctrl->handler,
+					       struct mt9t031, hdl);
+	struct v4l2_subdev *sd = &mt9t031->subdev;
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct v4l2_ctrl *exp = mt9t031->exposure;
+	int data;
+
+	switch (ctrl->id) {
+	case V4L2_CID_VFLIP:
+		if (ctrl->val)
+			data = reg_set(client, MT9T031_READ_MODE_2, 0x8000);
+		else
+			data = reg_clear(client, MT9T031_READ_MODE_2, 0x8000);
+		if (data < 0)
+			return -EIO;
+		return 0;
+	case V4L2_CID_HFLIP:
+		if (ctrl->val)
+			data = reg_set(client, MT9T031_READ_MODE_2, 0x4000);
+		else
+			data = reg_clear(client, MT9T031_READ_MODE_2, 0x4000);
+		if (data < 0)
+			return -EIO;
+		return 0;
+	case V4L2_CID_GAIN:
+		/* See Datasheet Table 7, Gain settings. */
+		if (ctrl->val <= ctrl->default_value) {
+			/* Pack it into 0..1 step 0.125, register values 0..8 */
+			unsigned long range = ctrl->default_value - ctrl->minimum;
+			data = ((ctrl->val - ctrl->minimum) * 8 + range / 2) / range;
+
+			dev_dbg(&client->dev, "Setting gain %d\n", data);
+			data = reg_write(client, MT9T031_GLOBAL_GAIN, data);
+			if (data < 0)
+				return -EIO;
+		} else {
+			/* Pack it into 1.125..128 variable step, register values 9..0x7860 */
+			/* We assume qctrl->maximum - qctrl->default_value - 1 > 0 */
+			unsigned long range = ctrl->maximum - ctrl->default_value - 1;
+			/* calculated gain: map 65..127 to 9..1024 step 0.125 */
+			unsigned long gain = ((ctrl->val - ctrl->default_value - 1) *
+					       1015 + range / 2) / range + 9;
+
+			if (gain <= 32)		/* calculated gain 9..32 -> 9..32 */
+				data = gain;
+			else if (gain <= 64)	/* calculated gain 33..64 -> 0x51..0x60 */
+				data = ((gain - 32) * 16 + 16) / 32 + 80;
+			else
+				/* calculated gain 65..1024 -> (1..120) << 8 + 0x60 */
+				data = (((gain - 64 + 7) * 32) & 0xff00) | 0x60;
+
+			dev_dbg(&client->dev, "Set gain from 0x%x to 0x%x\n",
+				reg_read(client, MT9T031_GLOBAL_GAIN), data);
+			data = reg_write(client, MT9T031_GLOBAL_GAIN, data);
+			if (data < 0)
+				return -EIO;
+		}
+		return 0;
+
+	case V4L2_CID_EXPOSURE_AUTO:
+		if (ctrl->val == V4L2_EXPOSURE_MANUAL) {
+			unsigned int range = exp->maximum - exp->minimum;
+			unsigned int shutter = ((exp->val - exp->minimum) * 1048 +
+						 range / 2) / range + 1;
+			u32 old;
+
+			get_shutter(client, &old);
+			dev_dbg(&client->dev, "Set shutter from %u to %u\n",
+				old, shutter);
+			if (set_shutter(client, shutter) < 0)
+				return -EIO;
+		} else {
+			const u16 vblank = MT9T031_VERTICAL_BLANK;
+			mt9t031->total_h = mt9t031->rect.height +
+				mt9t031->y_skip_top + vblank;
+
+			if (set_shutter(client, mt9t031->total_h) < 0)
+				return -EIO;
+		}
+		return 0;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/*
+ * Power Management:
+ * This function does nothing for now but must be present for pm to work
+ */
+static int mt9t031_runtime_suspend(struct device *dev)
+{
+	return 0;
+}
+
+/*
+ * Power Management:
+ * COLUMN_ADDRESS_MODE and ROW_ADDRESS_MODE are not rewritten if unchanged
+ * they are however changed at reset if the platform hook is present
+ * thus we rewrite them with the values stored by the driver
+ */
+static int mt9t031_runtime_resume(struct device *dev)
+{
+	struct video_device *vdev = to_video_device(dev);
+	struct v4l2_subdev *sd = soc_camera_vdev_to_subdev(vdev);
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+
+	int ret;
+	u16 xbin, ybin;
+
+	xbin = min(mt9t031->xskip, (u16)3);
+	ybin = min(mt9t031->yskip, (u16)3);
+
+	ret = reg_write(client, MT9T031_COLUMN_ADDRESS_MODE,
+		((xbin - 1) << 4) | (mt9t031->xskip - 1));
+	if (ret < 0)
+		return ret;
+
+	ret = reg_write(client, MT9T031_ROW_ADDRESS_MODE,
+		((ybin - 1) << 4) | (mt9t031->yskip - 1));
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static struct dev_pm_ops mt9t031_dev_pm_ops = {
+	.runtime_suspend	= mt9t031_runtime_suspend,
+	.runtime_resume		= mt9t031_runtime_resume,
+};
+
+static struct device_type mt9t031_dev_type = {
+	.name	= "MT9T031",
+	.pm	= &mt9t031_dev_pm_ops,
+};
+
+static int mt9t031_s_power(struct v4l2_subdev *sd, int on)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct soc_camera_link *icl = soc_camera_i2c_to_link(client);
+	struct video_device *vdev = soc_camera_i2c_to_vdev(client);
+	int ret;
+
+	if (on) {
+		ret = soc_camera_power_on(&client->dev, icl);
+		if (ret < 0)
+			return ret;
+		vdev->dev.type = &mt9t031_dev_type;
+	} else {
+		vdev->dev.type = NULL;
+		soc_camera_power_off(&client->dev, icl);
+	}
+
+	return 0;
+}
+
+/*
+ * Interface active, can use i2c. If it fails, it can indeed mean, that
+ * this wasn't our capture interface, so, we wait for the right one
+ */
+static int mt9t031_video_probe(struct i2c_client *client)
+{
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+	s32 data;
+	int ret;
+
+	ret = mt9t031_s_power(&mt9t031->subdev, 1);
+	if (ret < 0)
+		return ret;
+
+	ret = mt9t031_idle(client);
+	if (ret < 0) {
+		dev_err(&client->dev, "Failed to initialise the camera\n");
+		goto done;
+	}
+
+	/* Read out the chip version register */
+	data = reg_read(client, MT9T031_CHIP_VERSION);
+
+	switch (data) {
+	case 0x1621:
+		mt9t031->model = V4L2_IDENT_MT9T031;
+		break;
+	default:
+		dev_err(&client->dev,
+			"No MT9T031 chip detected, register read %x\n", data);
+		ret = -ENODEV;
+		goto done;
+	}
+
+	dev_info(&client->dev, "Detected a MT9T031 chip ID %x\n", data);
+
+	ret = v4l2_ctrl_handler_setup(&mt9t031->hdl);
+
+done:
+	mt9t031_s_power(&mt9t031->subdev, 0);
+
+	return ret;
+}
+
+static int mt9t031_g_skip_top_lines(struct v4l2_subdev *sd, u32 *lines)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+
+	*lines = mt9t031->y_skip_top;
+
+	return 0;
+}
+
+static const struct v4l2_ctrl_ops mt9t031_ctrl_ops = {
+	.g_volatile_ctrl = mt9t031_g_volatile_ctrl,
+	.s_ctrl = mt9t031_s_ctrl,
+};
+
+static struct v4l2_subdev_core_ops mt9t031_subdev_core_ops = {
+	.g_chip_ident	= mt9t031_g_chip_ident,
+	.s_power	= mt9t031_s_power,
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+	.g_register	= mt9t031_g_register,
+	.s_register	= mt9t031_s_register,
+#endif
+};
+
+static int mt9t031_enum_fmt(struct v4l2_subdev *sd, unsigned int index,
+			    enum v4l2_mbus_pixelcode *code)
+{
+	if (index)
+		return -EINVAL;
+
+	*code = V4L2_MBUS_FMT_SBGGR10_1X10;
+	return 0;
+}
+
+static int mt9t031_g_mbus_config(struct v4l2_subdev *sd,
+				struct v4l2_mbus_config *cfg)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct soc_camera_link *icl = soc_camera_i2c_to_link(client);
+
+	cfg->flags = V4L2_MBUS_MASTER | V4L2_MBUS_PCLK_SAMPLE_RISING |
+		V4L2_MBUS_PCLK_SAMPLE_FALLING | V4L2_MBUS_HSYNC_ACTIVE_HIGH |
+		V4L2_MBUS_VSYNC_ACTIVE_HIGH | V4L2_MBUS_DATA_ACTIVE_HIGH;
+	cfg->type = V4L2_MBUS_PARALLEL;
+	cfg->flags = soc_camera_apply_board_flags(icl, cfg);
+
+	return 0;
+}
+
+static int mt9t031_s_mbus_config(struct v4l2_subdev *sd,
+				const struct v4l2_mbus_config *cfg)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct soc_camera_link *icl = soc_camera_i2c_to_link(client);
+
+	if (soc_camera_apply_board_flags(icl, cfg) &
+	    V4L2_MBUS_PCLK_SAMPLE_FALLING)
+		return reg_clear(client, MT9T031_PIXEL_CLOCK_CONTROL, 0x8000);
+	else
+		return reg_set(client, MT9T031_PIXEL_CLOCK_CONTROL, 0x8000);
+}
+
+static struct v4l2_subdev_video_ops mt9t031_subdev_video_ops = {
+	.s_stream	= mt9t031_s_stream,
+	.s_mbus_fmt	= mt9t031_s_fmt,
+	.g_mbus_fmt	= mt9t031_g_fmt,
+	.try_mbus_fmt	= mt9t031_try_fmt,
+	.s_crop		= mt9t031_s_crop,
+	.g_crop		= mt9t031_g_crop,
+	.cropcap	= mt9t031_cropcap,
+	.enum_mbus_fmt	= mt9t031_enum_fmt,
+	.g_mbus_config	= mt9t031_g_mbus_config,
+	.s_mbus_config	= mt9t031_s_mbus_config,
+};
+
+static struct v4l2_subdev_sensor_ops mt9t031_subdev_sensor_ops = {
+	.g_skip_top_lines	= mt9t031_g_skip_top_lines,
+};
+
+static struct v4l2_subdev_ops mt9t031_subdev_ops = {
+	.core	= &mt9t031_subdev_core_ops,
+	.video	= &mt9t031_subdev_video_ops,
+	.sensor	= &mt9t031_subdev_sensor_ops,
+};
+
+static int mt9t031_probe(struct i2c_client *client,
+			 const struct i2c_device_id *did)
+{
+	struct mt9t031 *mt9t031;
+	struct soc_camera_link *icl = soc_camera_i2c_to_link(client);
+	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+	int ret;
+
+	if (!icl) {
+		dev_err(&client->dev, "MT9T031 driver needs platform data\n");
+		return -EINVAL;
+	}
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) {
+		dev_warn(&adapter->dev,
+			 "I2C-Adapter doesn't support I2C_FUNC_SMBUS_WORD\n");
+		return -EIO;
+	}
+
+	mt9t031 = kzalloc(sizeof(struct mt9t031), GFP_KERNEL);
+	if (!mt9t031)
+		return -ENOMEM;
+
+	v4l2_i2c_subdev_init(&mt9t031->subdev, client, &mt9t031_subdev_ops);
+	v4l2_ctrl_handler_init(&mt9t031->hdl, 5);
+	v4l2_ctrl_new_std(&mt9t031->hdl, &mt9t031_ctrl_ops,
+			V4L2_CID_VFLIP, 0, 1, 1, 0);
+	v4l2_ctrl_new_std(&mt9t031->hdl, &mt9t031_ctrl_ops,
+			V4L2_CID_HFLIP, 0, 1, 1, 0);
+	v4l2_ctrl_new_std(&mt9t031->hdl, &mt9t031_ctrl_ops,
+			V4L2_CID_GAIN, 0, 127, 1, 64);
+
+	/*
+	 * Simulated autoexposure. If enabled, we calculate shutter width
+	 * ourselves in the driver based on vertical blanking and frame width
+	 */
+	mt9t031->autoexposure = v4l2_ctrl_new_std_menu(&mt9t031->hdl,
+			&mt9t031_ctrl_ops, V4L2_CID_EXPOSURE_AUTO, 1, 0,
+			V4L2_EXPOSURE_AUTO);
+	mt9t031->exposure = v4l2_ctrl_new_std(&mt9t031->hdl, &mt9t031_ctrl_ops,
+			V4L2_CID_EXPOSURE, 1, 255, 1, 255);
+
+	mt9t031->subdev.ctrl_handler = &mt9t031->hdl;
+	if (mt9t031->hdl.error) {
+		int err = mt9t031->hdl.error;
+
+		kfree(mt9t031);
+		return err;
+	}
+	v4l2_ctrl_auto_cluster(2, &mt9t031->autoexposure,
+				V4L2_EXPOSURE_MANUAL, true);
+
+	mt9t031->y_skip_top	= 0;
+	mt9t031->rect.left	= MT9T031_COLUMN_SKIP;
+	mt9t031->rect.top	= MT9T031_ROW_SKIP;
+	mt9t031->rect.width	= MT9T031_MAX_WIDTH;
+	mt9t031->rect.height	= MT9T031_MAX_HEIGHT;
+
+	mt9t031->xskip = 1;
+	mt9t031->yskip = 1;
+
+	ret = mt9t031_video_probe(client);
+	if (ret) {
+		v4l2_ctrl_handler_free(&mt9t031->hdl);
+		kfree(mt9t031);
+	}
+
+	return ret;
+}
+
+static int mt9t031_remove(struct i2c_client *client)
+{
+	struct mt9t031 *mt9t031 = to_mt9t031(client);
+
+	v4l2_device_unregister_subdev(&mt9t031->subdev);
+	v4l2_ctrl_handler_free(&mt9t031->hdl);
+	kfree(mt9t031);
+
+	return 0;
+}
+
+static const struct i2c_device_id mt9t031_id[] = {
+	{ "mt9t031", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mt9t031_id);
+
+static struct i2c_driver mt9t031_i2c_driver = {
+	.driver = {
+		.name = "mt9t031",
+	},
+	.probe		= mt9t031_probe,
+	.remove		= mt9t031_remove,
+	.id_table	= mt9t031_id,
+};
+
+module_i2c_driver(mt9t031_i2c_driver);
+
+MODULE_DESCRIPTION("Micron MT9T031 Camera driver");
+MODULE_AUTHOR("Guennadi Liakhovetski <lg@denx.de>");
+MODULE_LICENSE("GPL v2");