[media] v4l: Add mt9v032 sensor driver

The MT9V032 is a parallel wide VGA sensor from Aptina (formerly Micron)
controlled through I2C.

The driver creates a V4L2 subdevice. It currently supports binning and
cropping, and the gain, auto gain, exposure, auto exposure and test
pattern controls.

Signed-off-by: Detlev Casanova <detlev.casanova@gmail.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 773 insertions, 0 deletions

diff --git a/drivers/media/video/mt9v032.c b/drivers/media/video/mt9v032.c
new file mode 100644
index 000000000000..1319c2c48aff
--- /dev/null
+++ b/drivers/media/video/mt9v032.c
@@ -0,0 +1,773 @@
+/*
+ * Driver for MT9V032 CMOS Image Sensor from Micron
+ *
+ * Copyright (C) 2010, Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *
+ * Based on the MT9M001 driver,
+ *
+ * Copyright (C) 2008, Guennadi Liakhovetski <kernel@pengutronix.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/delay.h>
+#include <linux/i2c.h>
+#include <linux/log2.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/videodev2.h>
+#include <linux/v4l2-mediabus.h>
+
+#include <media/mt9v032.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-subdev.h>
+
+#define MT9V032_PIXEL_ARRAY_HEIGHT			492
+#define MT9V032_PIXEL_ARRAY_WIDTH			782
+
+#define MT9V032_CHIP_VERSION				0x00
+#define		MT9V032_CHIP_ID_REV1			0x1311
+#define		MT9V032_CHIP_ID_REV3			0x1313
+#define MT9V032_ROW_START				0x01
+#define		MT9V032_ROW_START_MIN			4
+#define		MT9V032_ROW_START_DEF			10
+#define		MT9V032_ROW_START_MAX			482
+#define MT9V032_COLUMN_START				0x02
+#define		MT9V032_COLUMN_START_MIN		1
+#define		MT9V032_COLUMN_START_DEF		2
+#define		MT9V032_COLUMN_START_MAX		752
+#define MT9V032_WINDOW_HEIGHT				0x03
+#define		MT9V032_WINDOW_HEIGHT_MIN		1
+#define		MT9V032_WINDOW_HEIGHT_DEF		480
+#define		MT9V032_WINDOW_HEIGHT_MAX		480
+#define MT9V032_WINDOW_WIDTH				0x04
+#define		MT9V032_WINDOW_WIDTH_MIN		1
+#define		MT9V032_WINDOW_WIDTH_DEF		752
+#define		MT9V032_WINDOW_WIDTH_MAX		752
+#define MT9V032_HORIZONTAL_BLANKING			0x05
+#define		MT9V032_HORIZONTAL_BLANKING_MIN		43
+#define		MT9V032_HORIZONTAL_BLANKING_MAX		1023
+#define MT9V032_VERTICAL_BLANKING			0x06
+#define		MT9V032_VERTICAL_BLANKING_MIN		4
+#define		MT9V032_VERTICAL_BLANKING_MAX		3000
+#define MT9V032_CHIP_CONTROL				0x07
+#define		MT9V032_CHIP_CONTROL_MASTER_MODE	(1 << 3)
+#define		MT9V032_CHIP_CONTROL_DOUT_ENABLE	(1 << 7)
+#define		MT9V032_CHIP_CONTROL_SEQUENTIAL		(1 << 8)
+#define MT9V032_SHUTTER_WIDTH1				0x08
+#define MT9V032_SHUTTER_WIDTH2				0x09
+#define MT9V032_SHUTTER_WIDTH_CONTROL			0x0a
+#define MT9V032_TOTAL_SHUTTER_WIDTH			0x0b
+#define		MT9V032_TOTAL_SHUTTER_WIDTH_MIN		1
+#define		MT9V032_TOTAL_SHUTTER_WIDTH_DEF		480
+#define		MT9V032_TOTAL_SHUTTER_WIDTH_MAX		32767
+#define MT9V032_RESET					0x0c
+#define MT9V032_READ_MODE				0x0d
+#define		MT9V032_READ_MODE_ROW_BIN_MASK		(3 << 0)
+#define		MT9V032_READ_MODE_ROW_BIN_SHIFT		0
+#define		MT9V032_READ_MODE_COLUMN_BIN_MASK	(3 << 2)
+#define		MT9V032_READ_MODE_COLUMN_BIN_SHIFT	2
+#define		MT9V032_READ_MODE_ROW_FLIP		(1 << 4)
+#define		MT9V032_READ_MODE_COLUMN_FLIP		(1 << 5)
+#define		MT9V032_READ_MODE_DARK_COLUMNS		(1 << 6)
+#define		MT9V032_READ_MODE_DARK_ROWS		(1 << 7)
+#define MT9V032_PIXEL_OPERATION_MODE			0x0f
+#define		MT9V032_PIXEL_OPERATION_MODE_COLOR	(1 << 2)
+#define		MT9V032_PIXEL_OPERATION_MODE_HDR	(1 << 6)
+#define MT9V032_ANALOG_GAIN				0x35
+#define		MT9V032_ANALOG_GAIN_MIN			16
+#define		MT9V032_ANALOG_GAIN_DEF			16
+#define		MT9V032_ANALOG_GAIN_MAX			64
+#define MT9V032_MAX_ANALOG_GAIN				0x36
+#define		MT9V032_MAX_ANALOG_GAIN_MAX		127
+#define MT9V032_FRAME_DARK_AVERAGE			0x42
+#define MT9V032_DARK_AVG_THRESH				0x46
+#define		MT9V032_DARK_AVG_LOW_THRESH_MASK	(255 << 0)
+#define		MT9V032_DARK_AVG_LOW_THRESH_SHIFT	0
+#define		MT9V032_DARK_AVG_HIGH_THRESH_MASK	(255 << 8)
+#define		MT9V032_DARK_AVG_HIGH_THRESH_SHIFT	8
+#define MT9V032_ROW_NOISE_CORR_CONTROL			0x70
+#define		MT9V032_ROW_NOISE_CORR_ENABLE		(1 << 5)
+#define		MT9V032_ROW_NOISE_CORR_USE_BLK_AVG	(1 << 7)
+#define MT9V032_PIXEL_CLOCK				0x74
+#define		MT9V032_PIXEL_CLOCK_INV_LINE		(1 << 0)
+#define		MT9V032_PIXEL_CLOCK_INV_FRAME		(1 << 1)
+#define		MT9V032_PIXEL_CLOCK_XOR_LINE		(1 << 2)
+#define		MT9V032_PIXEL_CLOCK_CONT_LINE		(1 << 3)
+#define		MT9V032_PIXEL_CLOCK_INV_PXL_CLK		(1 << 4)
+#define MT9V032_TEST_PATTERN				0x7f
+#define		MT9V032_TEST_PATTERN_DATA_MASK		(1023 << 0)
+#define		MT9V032_TEST_PATTERN_DATA_SHIFT		0
+#define		MT9V032_TEST_PATTERN_USE_DATA		(1 << 10)
+#define		MT9V032_TEST_PATTERN_GRAY_MASK		(3 << 11)
+#define		MT9V032_TEST_PATTERN_GRAY_NONE		(0 << 11)
+#define		MT9V032_TEST_PATTERN_GRAY_VERTICAL	(1 << 11)
+#define		MT9V032_TEST_PATTERN_GRAY_HORIZONTAL	(2 << 11)
+#define		MT9V032_TEST_PATTERN_GRAY_DIAGONAL	(3 << 11)
+#define		MT9V032_TEST_PATTERN_ENABLE		(1 << 13)
+#define		MT9V032_TEST_PATTERN_FLIP		(1 << 14)
+#define MT9V032_AEC_AGC_ENABLE				0xaf
+#define		MT9V032_AEC_ENABLE			(1 << 0)
+#define		MT9V032_AGC_ENABLE			(1 << 1)
+#define MT9V032_THERMAL_INFO				0xc1
+
+struct mt9v032 {
+	struct v4l2_subdev subdev;
+	struct media_pad pad;
+
+	struct v4l2_mbus_framefmt format;
+	struct v4l2_rect crop;
+
+	struct v4l2_ctrl_handler ctrls;
+
+	struct mutex power_lock;
+	int power_count;
+
+	struct mt9v032_platform_data *pdata;
+	u16 chip_control;
+	u16 aec_agc;
+};
+
+static struct mt9v032 *to_mt9v032(struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct mt9v032, subdev);
+}
+
+static int mt9v032_read(struct i2c_client *client, const u8 reg)
+{
+	s32 data = i2c_smbus_read_word_data(client, reg);
+	dev_dbg(&client->dev, "%s: read 0x%04x from 0x%02x\n", __func__,
+		swab16(data), reg);
+	return data < 0 ? data : swab16(data);
+}
+
+static int mt9v032_write(struct i2c_client *client, const u8 reg,
+			 const u16 data)
+{
+	dev_dbg(&client->dev, "%s: writing 0x%04x to 0x%02x\n", __func__,
+		data, reg);
+	return i2c_smbus_write_word_data(client, reg, swab16(data));
+}
+
+static int mt9v032_set_chip_control(struct mt9v032 *mt9v032, u16 clear, u16 set)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&mt9v032->subdev);
+	u16 value = (mt9v032->chip_control & ~clear) | set;
+	int ret;
+
+	ret = mt9v032_write(client, MT9V032_CHIP_CONTROL, value);
+	if (ret < 0)
+		return ret;
+
+	mt9v032->chip_control = value;
+	return 0;
+}
+
+static int
+mt9v032_update_aec_agc(struct mt9v032 *mt9v032, u16 which, int enable)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&mt9v032->subdev);
+	u16 value = mt9v032->aec_agc;
+	int ret;
+
+	if (enable)
+		value |= which;
+	else
+		value &= ~which;
+
+	ret = mt9v032_write(client, MT9V032_AEC_AGC_ENABLE, value);
+	if (ret < 0)
+		return ret;
+
+	mt9v032->aec_agc = value;
+	return 0;
+}
+
+static int mt9v032_power_on(struct mt9v032 *mt9v032)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&mt9v032->subdev);
+	int ret;
+
+	if (mt9v032->pdata->set_clock) {
+		mt9v032->pdata->set_clock(&mt9v032->subdev, 25000000);
+		udelay(1);
+	}
+
+	/* Reset the chip and stop data read out */
+	ret = mt9v032_write(client, MT9V032_RESET, 1);
+	if (ret < 0)
+		return ret;
+
+	ret = mt9v032_write(client, MT9V032_RESET, 0);
+	if (ret < 0)
+		return ret;
+
+	return mt9v032_write(client, MT9V032_CHIP_CONTROL, 0);
+}
+
+static void mt9v032_power_off(struct mt9v032 *mt9v032)
+{
+	if (mt9v032->pdata->set_clock)
+		mt9v032->pdata->set_clock(&mt9v032->subdev, 0);
+}
+
+static int __mt9v032_set_power(struct mt9v032 *mt9v032, bool on)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&mt9v032->subdev);
+	int ret;
+
+	if (!on) {
+		mt9v032_power_off(mt9v032);
+		return 0;
+	}
+
+	ret = mt9v032_power_on(mt9v032);
+	if (ret < 0)
+		return ret;
+
+	/* Configure the pixel clock polarity */
+	if (mt9v032->pdata && mt9v032->pdata->clk_pol) {
+		ret = mt9v032_write(client, MT9V032_PIXEL_CLOCK,
+				MT9V032_PIXEL_CLOCK_INV_PXL_CLK);
+		if (ret < 0)
+			return ret;
+	}
+
+	/* Disable the noise correction algorithm and restore the controls. */
+	ret = mt9v032_write(client, MT9V032_ROW_NOISE_CORR_CONTROL, 0);
+	if (ret < 0)
+		return ret;
+
+	return v4l2_ctrl_handler_setup(&mt9v032->ctrls);
+}
+
+/* -----------------------------------------------------------------------------
+ * V4L2 subdev video operations
+ */
+
+static struct v4l2_mbus_framefmt *
+__mt9v032_get_pad_format(struct mt9v032 *mt9v032, struct v4l2_subdev_fh *fh,
+			 unsigned int pad, enum v4l2_subdev_format_whence which)
+{
+	switch (which) {
+	case V4L2_SUBDEV_FORMAT_TRY:
+		return v4l2_subdev_get_try_format(fh, pad);
+	case V4L2_SUBDEV_FORMAT_ACTIVE:
+		return &mt9v032->format;
+	default:
+		return NULL;
+	}
+}
+
+static struct v4l2_rect *
+__mt9v032_get_pad_crop(struct mt9v032 *mt9v032, struct v4l2_subdev_fh *fh,
+		       unsigned int pad, enum v4l2_subdev_format_whence which)
+{
+	switch (which) {
+	case V4L2_SUBDEV_FORMAT_TRY:
+		return v4l2_subdev_get_try_crop(fh, pad);
+	case V4L2_SUBDEV_FORMAT_ACTIVE:
+		return &mt9v032->crop;
+	default:
+		return NULL;
+	}
+}
+
+static int mt9v032_s_stream(struct v4l2_subdev *subdev, int enable)
+{
+	const u16 mode = MT9V032_CHIP_CONTROL_MASTER_MODE
+		       | MT9V032_CHIP_CONTROL_DOUT_ENABLE
+		       | MT9V032_CHIP_CONTROL_SEQUENTIAL;
+	struct i2c_client *client = v4l2_get_subdevdata(subdev);
+	struct mt9v032 *mt9v032 = to_mt9v032(subdev);
+	struct v4l2_mbus_framefmt *format = &mt9v032->format;
+	struct v4l2_rect *crop = &mt9v032->crop;
+	unsigned int hratio;
+	unsigned int vratio;
+	int ret;
+
+	if (!enable)
+		return mt9v032_set_chip_control(mt9v032, mode, 0);
+
+	/* Configure the window size and row/column bin */
+	hratio = DIV_ROUND_CLOSEST(crop->width, format->width);
+	vratio = DIV_ROUND_CLOSEST(crop->height, format->height);
+
+	ret = mt9v032_write(client, MT9V032_READ_MODE,
+		    (hratio - 1) << MT9V032_READ_MODE_ROW_BIN_SHIFT |
+		    (vratio - 1) << MT9V032_READ_MODE_COLUMN_BIN_SHIFT);
+	if (ret < 0)
+		return ret;
+
+	ret = mt9v032_write(client, MT9V032_COLUMN_START, crop->left);
+	if (ret < 0)
+		return ret;
+
+	ret = mt9v032_write(client, MT9V032_ROW_START, crop->top);
+	if (ret < 0)
+		return ret;
+
+	ret = mt9v032_write(client, MT9V032_WINDOW_WIDTH, crop->width);
+	if (ret < 0)
+		return ret;
+
+	ret = mt9v032_write(client, MT9V032_WINDOW_HEIGHT, crop->height);
+	if (ret < 0)
+		return ret;
+
+	ret = mt9v032_write(client, MT9V032_HORIZONTAL_BLANKING,
+			    max(43, 660 - crop->width));
+	if (ret < 0)
+		return ret;
+
+	/* Switch to master "normal" mode */
+	return mt9v032_set_chip_control(mt9v032, 0, mode);
+}
+
+static int mt9v032_enum_mbus_code(struct v4l2_subdev *subdev,
+				  struct v4l2_subdev_fh *fh,
+				  struct v4l2_subdev_mbus_code_enum *code)
+{
+	if (code->index > 0)
+		return -EINVAL;
+
+	code->code = V4L2_MBUS_FMT_SGRBG10_1X10;
+	return 0;
+}
+
+static int mt9v032_enum_frame_size(struct v4l2_subdev *subdev,
+				   struct v4l2_subdev_fh *fh,
+				   struct v4l2_subdev_frame_size_enum *fse)
+{
+	if (fse->index >= 8 || fse->code != V4L2_MBUS_FMT_SGRBG10_1X10)
+		return -EINVAL;
+
+	fse->min_width = MT9V032_WINDOW_WIDTH_DEF / fse->index;
+	fse->max_width = fse->min_width;
+	fse->min_height = MT9V032_WINDOW_HEIGHT_DEF / fse->index;
+	fse->max_height = fse->min_height;
+
+	return 0;
+}
+
+static int mt9v032_get_format(struct v4l2_subdev *subdev,
+			      struct v4l2_subdev_fh *fh,
+			      struct v4l2_subdev_format *format)
+{
+	struct mt9v032 *mt9v032 = to_mt9v032(subdev);
+
+	format->format = *__mt9v032_get_pad_format(mt9v032, fh, format->pad,
+						   format->which);
+	return 0;
+}
+
+static int mt9v032_set_format(struct v4l2_subdev *subdev,
+			      struct v4l2_subdev_fh *fh,
+			      struct v4l2_subdev_format *format)
+{
+	struct mt9v032 *mt9v032 = to_mt9v032(subdev);
+	struct v4l2_mbus_framefmt *__format;
+	struct v4l2_rect *__crop;
+	unsigned int width;
+	unsigned int height;
+	unsigned int hratio;
+	unsigned int vratio;
+
+	__crop = __mt9v032_get_pad_crop(mt9v032, fh, format->pad,
+					format->which);
+
+	/* Clamp the width and height to avoid dividing by zero. */
+	width = clamp_t(unsigned int, ALIGN(format->format.width, 2),
+			max(__crop->width / 8, MT9V032_WINDOW_WIDTH_MIN),
+			__crop->width);
+	height = clamp_t(unsigned int, ALIGN(format->format.height, 2),
+			 max(__crop->height / 8, MT9V032_WINDOW_HEIGHT_MIN),
+			 __crop->height);
+
+	hratio = DIV_ROUND_CLOSEST(__crop->width, width);
+	vratio = DIV_ROUND_CLOSEST(__crop->height, height);
+
+	__format = __mt9v032_get_pad_format(mt9v032, fh, format->pad,
+					    format->which);
+	__format->width = __crop->width / hratio;
+	__format->height = __crop->height / vratio;
+
+	format->format = *__format;
+
+	return 0;
+}
+
+static int mt9v032_get_crop(struct v4l2_subdev *subdev,
+			    struct v4l2_subdev_fh *fh,
+			    struct v4l2_subdev_crop *crop)
+{
+	struct mt9v032 *mt9v032 = to_mt9v032(subdev);
+
+	crop->rect = *__mt9v032_get_pad_crop(mt9v032, fh, crop->pad,
+					     crop->which);
+	return 0;
+}
+
+static int mt9v032_set_crop(struct v4l2_subdev *subdev,
+			    struct v4l2_subdev_fh *fh,
+			    struct v4l2_subdev_crop *crop)
+{
+	struct mt9v032 *mt9v032 = to_mt9v032(subdev);
+	struct v4l2_mbus_framefmt *__format;
+	struct v4l2_rect *__crop;
+	struct v4l2_rect rect;
+
+	/* Clamp the crop rectangle boundaries and align them to a multiple of 2
+	 * pixels.
+	 */
+	rect.left = clamp(ALIGN(crop->rect.left, 2),
+			  MT9V032_COLUMN_START_MIN,
+			  MT9V032_COLUMN_START_MAX);
+	rect.top = clamp(ALIGN(crop->rect.top, 2),
+			 MT9V032_ROW_START_MIN,
+			 MT9V032_ROW_START_MAX);
+	rect.width = clamp(ALIGN(crop->rect.width, 2),
+			   MT9V032_WINDOW_WIDTH_MIN,
+			   MT9V032_WINDOW_WIDTH_MAX);
+	rect.height = clamp(ALIGN(crop->rect.height, 2),
+			    MT9V032_WINDOW_HEIGHT_MIN,
+			    MT9V032_WINDOW_HEIGHT_MAX);
+
+	rect.width = min(rect.width, MT9V032_PIXEL_ARRAY_WIDTH - rect.left);
+	rect.height = min(rect.height, MT9V032_PIXEL_ARRAY_HEIGHT - rect.top);
+
+	__crop = __mt9v032_get_pad_crop(mt9v032, fh, crop->pad, crop->which);
+
+	if (rect.width != __crop->width || rect.height != __crop->height) {
+		/* Reset the output image size if the crop rectangle size has
+		 * been modified.
+		 */
+		__format = __mt9v032_get_pad_format(mt9v032, fh, crop->pad,
+						    crop->which);
+		__format->width = rect.width;
+		__format->height = rect.height;
+	}
+
+	*__crop = rect;
+	crop->rect = rect;
+
+	return 0;
+}
+
+/* -----------------------------------------------------------------------------
+ * V4L2 subdev control operations
+ */
+
+#define V4L2_CID_TEST_PATTERN		(V4L2_CID_USER_BASE | 0x1001)
+
+static int mt9v032_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct mt9v032 *mt9v032 =
+			container_of(ctrl->handler, struct mt9v032, ctrls);
+	struct i2c_client *client = v4l2_get_subdevdata(&mt9v032->subdev);
+	u16 data;
+
+	switch (ctrl->id) {
+	case V4L2_CID_AUTOGAIN:
+		return mt9v032_update_aec_agc(mt9v032, MT9V032_AGC_ENABLE,
+					      ctrl->val);
+
+	case V4L2_CID_GAIN:
+		return mt9v032_write(client, MT9V032_ANALOG_GAIN, ctrl->val);
+
+	case V4L2_CID_EXPOSURE_AUTO:
+		return mt9v032_update_aec_agc(mt9v032, MT9V032_AEC_ENABLE,
+					      ctrl->val);
+
+	case V4L2_CID_EXPOSURE:
+		return mt9v032_write(client, MT9V032_TOTAL_SHUTTER_WIDTH,
+				     ctrl->val);
+
+	case V4L2_CID_TEST_PATTERN:
+		switch (ctrl->val) {
+		case 0:
+			data = 0;
+			break;
+		case 1:
+			data = MT9V032_TEST_PATTERN_GRAY_VERTICAL
+			     | MT9V032_TEST_PATTERN_ENABLE;
+			break;
+		case 2:
+			data = MT9V032_TEST_PATTERN_GRAY_HORIZONTAL
+			     | MT9V032_TEST_PATTERN_ENABLE;
+			break;
+		case 3:
+			data = MT9V032_TEST_PATTERN_GRAY_DIAGONAL
+			     | MT9V032_TEST_PATTERN_ENABLE;
+			break;
+		default:
+			data = (ctrl->val << MT9V032_TEST_PATTERN_DATA_SHIFT)
+			     | MT9V032_TEST_PATTERN_USE_DATA
+			     | MT9V032_TEST_PATTERN_ENABLE
+			     | MT9V032_TEST_PATTERN_FLIP;
+			break;
+		}
+
+		return mt9v032_write(client, MT9V032_TEST_PATTERN, data);
+	}
+
+	return 0;
+}
+
+static struct v4l2_ctrl_ops mt9v032_ctrl_ops = {
+	.s_ctrl = mt9v032_s_ctrl,
+};
+
+static const struct v4l2_ctrl_config mt9v032_ctrls[] = {
+	{
+		.ops		= &mt9v032_ctrl_ops,
+		.id		= V4L2_CID_TEST_PATTERN,
+		.type		= V4L2_CTRL_TYPE_INTEGER,
+		.name		= "Test pattern",
+		.min		= 0,
+		.max		= 1023,
+		.step		= 1,
+		.def		= 0,
+		.flags		= 0,
+	}
+};
+
+/* -----------------------------------------------------------------------------
+ * V4L2 subdev core operations
+ */
+
+static int mt9v032_set_power(struct v4l2_subdev *subdev, int on)
+{
+	struct mt9v032 *mt9v032 = to_mt9v032(subdev);
+	int ret = 0;
+
+	mutex_lock(&mt9v032->power_lock);
+
+	/* If the power count is modified from 0 to != 0 or from != 0 to 0,
+	 * update the power state.
+	 */
+	if (mt9v032->power_count == !on) {
+		ret = __mt9v032_set_power(mt9v032, !!on);
+		if (ret < 0)
+			goto done;
+	}
+
+	/* Update the power count. */
+	mt9v032->power_count += on ? 1 : -1;
+	WARN_ON(mt9v032->power_count < 0);
+
+done:
+	mutex_unlock(&mt9v032->power_lock);
+	return ret;
+}
+
+/* -----------------------------------------------------------------------------
+ * V4L2 subdev internal operations
+ */
+
+static int mt9v032_registered(struct v4l2_subdev *subdev)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(subdev);
+	struct mt9v032 *mt9v032 = to_mt9v032(subdev);
+	s32 data;
+	int ret;
+
+	dev_info(&client->dev, "Probing MT9V032 at address 0x%02x\n",
+			client->addr);
+
+	ret = mt9v032_power_on(mt9v032);
+	if (ret < 0) {
+		dev_err(&client->dev, "MT9V032 power up failed\n");
+		return ret;
+	}
+
+	/* Read and check the sensor version */
+	data = mt9v032_read(client, MT9V032_CHIP_VERSION);
+	if (data != MT9V032_CHIP_ID_REV1 && data != MT9V032_CHIP_ID_REV3) {
+		dev_err(&client->dev, "MT9V032 not detected, wrong version "
+				"0x%04x\n", data);
+		return -ENODEV;
+	}
+
+	mt9v032_power_off(mt9v032);
+
+	dev_info(&client->dev, "MT9V032 detected at address 0x%02x\n",
+			client->addr);
+
+	return ret;
+}
+
+static int mt9v032_open(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh)
+{
+	struct v4l2_mbus_framefmt *format;
+	struct v4l2_rect *crop;
+
+	crop = v4l2_subdev_get_try_crop(fh, 0);
+	crop->left = MT9V032_COLUMN_START_DEF;
+	crop->top = MT9V032_ROW_START_DEF;
+	crop->width = MT9V032_WINDOW_WIDTH_DEF;
+	crop->height = MT9V032_WINDOW_HEIGHT_DEF;
+
+	format = v4l2_subdev_get_try_format(fh, 0);
+	format->code = V4L2_MBUS_FMT_SGRBG10_1X10;
+	format->width = MT9V032_WINDOW_WIDTH_DEF;
+	format->height = MT9V032_WINDOW_HEIGHT_DEF;
+	format->field = V4L2_FIELD_NONE;
+	format->colorspace = V4L2_COLORSPACE_SRGB;
+
+	return mt9v032_set_power(subdev, 1);
+}
+
+static int mt9v032_close(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh)
+{
+	return mt9v032_set_power(subdev, 0);
+}
+
+static struct v4l2_subdev_core_ops mt9v032_subdev_core_ops = {
+	.s_power	= mt9v032_set_power,
+};
+
+static struct v4l2_subdev_video_ops mt9v032_subdev_video_ops = {
+	.s_stream	= mt9v032_s_stream,
+};
+
+static struct v4l2_subdev_pad_ops mt9v032_subdev_pad_ops = {
+	.enum_mbus_code = mt9v032_enum_mbus_code,
+	.enum_frame_size = mt9v032_enum_frame_size,
+	.get_fmt = mt9v032_get_format,
+	.set_fmt = mt9v032_set_format,
+	.get_crop = mt9v032_get_crop,
+	.set_crop = mt9v032_set_crop,
+};
+
+static struct v4l2_subdev_ops mt9v032_subdev_ops = {
+	.core	= &mt9v032_subdev_core_ops,
+	.video	= &mt9v032_subdev_video_ops,
+	.pad	= &mt9v032_subdev_pad_ops,
+};
+
+static const struct v4l2_subdev_internal_ops mt9v032_subdev_internal_ops = {
+	.registered = mt9v032_registered,
+	.open = mt9v032_open,
+	.close = mt9v032_close,
+};
+
+/* -----------------------------------------------------------------------------
+ * Driver initialization and probing
+ */
+
+static int mt9v032_probe(struct i2c_client *client,
+		const struct i2c_device_id *did)
+{
+	struct mt9v032 *mt9v032;
+	unsigned int i;
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_SMBUS_WORD_DATA)) {
+		dev_warn(&client->adapter->dev,
+			 "I2C-Adapter doesn't support I2C_FUNC_SMBUS_WORD\n");
+		return -EIO;
+	}
+
+	mt9v032 = kzalloc(sizeof(*mt9v032), GFP_KERNEL);
+	if (!mt9v032)
+		return -ENOMEM;
+
+	mutex_init(&mt9v032->power_lock);
+	mt9v032->pdata = client->dev.platform_data;
+
+	v4l2_ctrl_handler_init(&mt9v032->ctrls, ARRAY_SIZE(mt9v032_ctrls) + 4);
+
+	v4l2_ctrl_new_std(&mt9v032->ctrls, &mt9v032_ctrl_ops,
+			  V4L2_CID_AUTOGAIN, 0, 1, 1, 1);
+	v4l2_ctrl_new_std(&mt9v032->ctrls, &mt9v032_ctrl_ops,
+			  V4L2_CID_GAIN, MT9V032_ANALOG_GAIN_MIN,
+			  MT9V032_ANALOG_GAIN_MAX, 1, MT9V032_ANALOG_GAIN_DEF);
+	v4l2_ctrl_new_std_menu(&mt9v032->ctrls, &mt9v032_ctrl_ops,
+			       V4L2_CID_EXPOSURE_AUTO, V4L2_EXPOSURE_MANUAL, 0,
+			       V4L2_EXPOSURE_AUTO);
+	v4l2_ctrl_new_std(&mt9v032->ctrls, &mt9v032_ctrl_ops,
+			  V4L2_CID_EXPOSURE, MT9V032_TOTAL_SHUTTER_WIDTH_MIN,
+			  MT9V032_TOTAL_SHUTTER_WIDTH_MAX, 1,
+			  MT9V032_TOTAL_SHUTTER_WIDTH_DEF);
+
+	for (i = 0; i < ARRAY_SIZE(mt9v032_ctrls); ++i)
+		v4l2_ctrl_new_custom(&mt9v032->ctrls, &mt9v032_ctrls[i], NULL);
+
+	mt9v032->subdev.ctrl_handler = &mt9v032->ctrls;
+
+	if (mt9v032->ctrls.error)
+		printk(KERN_INFO "%s: control initialization error %d\n",
+		       __func__, mt9v032->ctrls.error);
+
+	mt9v032->crop.left = MT9V032_COLUMN_START_DEF;
+	mt9v032->crop.top = MT9V032_ROW_START_DEF;
+	mt9v032->crop.width = MT9V032_WINDOW_WIDTH_DEF;
+	mt9v032->crop.height = MT9V032_WINDOW_HEIGHT_DEF;
+
+	mt9v032->format.code = V4L2_MBUS_FMT_SGRBG10_1X10;
+	mt9v032->format.width = MT9V032_WINDOW_WIDTH_DEF;
+	mt9v032->format.height = MT9V032_WINDOW_HEIGHT_DEF;
+	mt9v032->format.field = V4L2_FIELD_NONE;
+	mt9v032->format.colorspace = V4L2_COLORSPACE_SRGB;
+
+	mt9v032->aec_agc = MT9V032_AEC_ENABLE | MT9V032_AGC_ENABLE;
+
+	v4l2_i2c_subdev_init(&mt9v032->subdev, client, &mt9v032_subdev_ops);
+	mt9v032->subdev.internal_ops = &mt9v032_subdev_internal_ops;
+	mt9v032->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+
+	mt9v032->pad.flags = MEDIA_PAD_FL_SOURCE;
+	ret = media_entity_init(&mt9v032->subdev.entity, 1, &mt9v032->pad, 0);
+	if (ret < 0)
+		kfree(mt9v032);
+
+	return ret;
+}
+
+static int mt9v032_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *subdev = i2c_get_clientdata(client);
+	struct mt9v032 *mt9v032 = to_mt9v032(subdev);
+
+	v4l2_device_unregister_subdev(subdev);
+	media_entity_cleanup(&subdev->entity);
+	kfree(mt9v032);
+	return 0;
+}
+
+static const struct i2c_device_id mt9v032_id[] = {
+	{ "mt9v032", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mt9v032_id);
+
+static struct i2c_driver mt9v032_driver = {
+	.driver = {
+		.name = "mt9v032",
+	},
+	.probe		= mt9v032_probe,
+	.remove		= mt9v032_remove,
+	.id_table	= mt9v032_id,
+};
+
+static int __init mt9v032_init(void)
+{
+	return i2c_add_driver(&mt9v032_driver);
+}
+
+static void __exit mt9v032_exit(void)
+{
+	i2c_del_driver(&mt9v032_driver);
+}
+
+module_init(mt9v032_init);
+module_exit(mt9v032_exit);
+
+MODULE_DESCRIPTION("Aptina MT9V032 Camera driver");
+MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
+MODULE_LICENSE("GPL");