V4L/DVB (7174): Add support for the MT9V022 camera

This driver supports Micron MT9V022 colour camera.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

3 files changed, 819 insertions, 0 deletions

diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
index 393bbf9..21f250b 100644
--- a/drivers/media/video/Kconfig
+++ b/drivers/media/video/Kconfig
@@ -860,6 +860,20 @@ config MT9M001_PCA9536_SWITCH
 	  Select this if your MT9M001 camera uses a PCA9536 I2C GPIO
 	  extender to switch between 8 and 10 bit datawidth modes
 
+config SOC_CAMERA_MT9V022
+	tristate "mt9v022 support"
+	depends on SOC_CAMERA && GENERIC_GPIO
+	select GPIO_PCA953X if MT9V022_PCA9536_SWITCH
+	help
+	  This driver supports MT9V022 cameras from Micron
+
+config MT9V022_PCA9536_SWITCH
+	bool "pca9536 datawidth switch for mt9v022"
+	depends on SOC_CAMERA_MT9V022
+	help
+	  Select this if your MT9V022 camera uses a PCA9536 I2C GPIO
+	  extender to switch between 8 and 10 bit datawidth modes
+
 config VIDEO_PXA27x
 	tristate "PXA27x Quick Capture Interface driver"
 	depends on VIDEO_DEV && PXA27x
diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile
index 9321f68..77cfaff 100644
--- a/drivers/media/video/Makefile
+++ b/drivers/media/video/Makefile
@@ -139,6 +139,7 @@ obj-$(CONFIG_VIDEO_CX23885) += cx23885/
 obj-$(CONFIG_VIDEO_PXA27x)	+= pxa_camera.o
 obj-$(CONFIG_SOC_CAMERA)	+= soc_camera.o
 obj-$(CONFIG_SOC_CAMERA_MT9M001)	+= mt9m001.o
+obj-$(CONFIG_SOC_CAMERA_MT9V022)	+= mt9v022.o
 
 EXTRA_CFLAGS += -Idrivers/media/dvb/dvb-core
 EXTRA_CFLAGS += -Idrivers/media/dvb/frontends
diff --git a/drivers/media/video/mt9v022.c b/drivers/media/video/mt9v022.c
new file mode 100644
index 0000000..9b406e4
--- /dev/null
+++ b/drivers/media/video/mt9v022.c
@@ -0,0 +1,804 @@
+/*
+ * Driver for MT9V022 CMOS Image Sensor from Micron
+ *
+ * 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/videodev2.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/log2.h>
+
+#include <media/v4l2-common.h>
+#include <media/v4l2-chip-ident.h>
+#include <media/soc_camera.h>
+
+#include <asm/gpio.h>
+
+/* mt9v022 i2c address 0x48, 0x4c, 0x58, 0x5c
+ * The platform has to define i2c_board_info
+ * and call i2c_register_board_info() */
+
+static char *sensor_type;
+module_param(sensor_type, charp, S_IRUGO);
+MODULE_PARM_DESC(sensor_type, "Sensor type: \"colour\" or \"monochrome\"\n");
+
+/* mt9v022 selected register addresses */
+#define MT9V022_CHIP_VERSION		0x00
+#define MT9V022_COLUMN_START		0x01
+#define MT9V022_ROW_START		0x02
+#define MT9V022_WINDOW_HEIGHT		0x03
+#define MT9V022_WINDOW_WIDTH		0x04
+#define MT9V022_HORIZONTAL_BLANKING	0x05
+#define MT9V022_VERTICAL_BLANKING	0x06
+#define MT9V022_CHIP_CONTROL		0x07
+#define MT9V022_SHUTTER_WIDTH1		0x08
+#define MT9V022_SHUTTER_WIDTH2		0x09
+#define MT9V022_SHUTTER_WIDTH_CTRL	0x0a
+#define MT9V022_TOTAL_SHUTTER_WIDTH	0x0b
+#define MT9V022_RESET			0x0c
+#define MT9V022_READ_MODE		0x0d
+#define MT9V022_MONITOR_MODE		0x0e
+#define MT9V022_PIXEL_OPERATION_MODE	0x0f
+#define MT9V022_LED_OUT_CONTROL		0x1b
+#define MT9V022_ADC_MODE_CONTROL	0x1c
+#define MT9V022_ANALOG_GAIN		0x34
+#define MT9V022_BLACK_LEVEL_CALIB_CTRL	0x47
+#define MT9V022_PIXCLK_FV_LV		0x74
+#define MT9V022_DIGITAL_TEST_PATTERN	0x7f
+#define MT9V022_AEC_AGC_ENABLE		0xAF
+#define MT9V022_MAX_TOTAL_SHUTTER_WIDTH	0xBD
+
+/* Progressive scan, master, defaults */
+#define MT9V022_CHIP_CONTROL_DEFAULT	0x188
+
+static const struct soc_camera_data_format mt9v022_formats[] = {
+	{
+		.name		= "RGB Bayer (sRGB)",
+		.depth		= 8,
+		.fourcc		= V4L2_PIX_FMT_SBGGR8,
+		.colorspace	= V4L2_COLORSPACE_SRGB,
+	}, {
+		.name		= "RGB Bayer (sRGB)",
+		.depth		= 10,
+		.fourcc		= V4L2_PIX_FMT_SBGGR16,
+		.colorspace	= V4L2_COLORSPACE_SRGB,
+	}, {
+		.name		= "Monochrome 10 bit",
+		.depth		= 10,
+		.fourcc		= V4L2_PIX_FMT_Y16,
+	}, {
+		.name		= "Monochrome 8 bit",
+		.depth		= 8,
+		.fourcc		= V4L2_PIX_FMT_GREY,
+	},
+};
+
+struct mt9v022 {
+	struct i2c_client *client;
+	struct soc_camera_device icd;
+	int model;	/* V4L2_IDENT_MT9M001* codes from v4l2-chip-ident.h */
+	int switch_gpio;
+	u16 chip_control;
+	unsigned char datawidth;
+};
+
+static int reg_read(struct soc_camera_device *icd, const u8 reg)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+	struct i2c_client *client = mt9v022->client;
+	s32 data = i2c_smbus_read_word_data(client, reg);
+	return data < 0 ? data : swab16(data);
+}
+
+static int reg_write(struct soc_camera_device *icd, const u8 reg,
+		     const u16 data)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+	return i2c_smbus_write_word_data(mt9v022->client, reg, swab16(data));
+}
+
+static int reg_set(struct soc_camera_device *icd, const u8 reg,
+		   const u16 data)
+{
+	int ret;
+
+	ret = reg_read(icd, reg);
+	if (ret < 0)
+		return ret;
+	return reg_write(icd, reg, ret | data);
+}
+
+static int reg_clear(struct soc_camera_device *icd, const u8 reg,
+		     const u16 data)
+{
+	int ret;
+
+	ret = reg_read(icd, reg);
+	if (ret < 0)
+		return ret;
+	return reg_write(icd, reg, ret & ~data);
+}
+
+static int mt9v022_init(struct soc_camera_device *icd)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+	int ret;
+
+	/* Almost the default mode: master, parallel, simultaneous, and an
+	 * undocumented bit 0x200, which is present in table 7, but not in 8,
+	 * plus snapshot mode to disable scan for now */
+	mt9v022->chip_control |= 0x10;
+	ret = reg_write(icd, MT9V022_CHIP_CONTROL, mt9v022->chip_control);
+	if (ret >= 0)
+		reg_write(icd, MT9V022_READ_MODE, 0x300);
+
+	/* All defaults */
+	if (ret >= 0)
+		/* AEC, AGC on */
+		ret = reg_set(icd, MT9V022_AEC_AGC_ENABLE, 0x3);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9V022_MAX_TOTAL_SHUTTER_WIDTH, 480);
+	if (ret >= 0)
+		/* default - auto */
+		ret = reg_clear(icd, MT9V022_BLACK_LEVEL_CALIB_CTRL, 1);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9V022_DIGITAL_TEST_PATTERN, 0);
+
+	return ret >= 0 ? 0 : -EIO;
+}
+
+static int mt9v022_release(struct soc_camera_device *icd)
+{
+	/* Nothing? */
+	return 0;
+}
+
+static int mt9v022_start_capture(struct soc_camera_device *icd)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+	/* Switch to master "normal" mode */
+	mt9v022->chip_control &= ~0x10;
+	if (reg_write(icd, MT9V022_CHIP_CONTROL,
+		      mt9v022->chip_control) < 0)
+		return -EIO;
+	return 0;
+}
+
+static int mt9v022_stop_capture(struct soc_camera_device *icd)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+	/* Switch to snapshot mode */
+	mt9v022->chip_control |= 0x10;
+	if (reg_write(icd, MT9V022_CHIP_CONTROL,
+		      mt9v022->chip_control) < 0)
+		return -EIO;
+	return 0;
+}
+
+static int bus_switch_request(struct mt9v022 *mt9v022, struct soc_camera_link *icl)
+{
+#ifdef CONFIG_MT9V022_PCA9536_SWITCH
+	int ret;
+	unsigned int gpio = icl->gpio;
+
+	if (gpio != NO_GPIO) {
+		/* We have a data bus switch. */
+		ret = gpio_request(gpio, "mt9v022");
+		if (ret < 0) {
+			dev_err(&mt9v022->client->dev, "Cannot get GPIO %u\n", gpio);
+			return ret;
+		}
+
+		ret = gpio_direction_output(gpio, 0);
+		if (ret < 0) {
+			dev_err(&mt9v022->client->dev,
+				"Cannot set GPIO %u to output\n", gpio);
+			gpio_free(gpio);
+			return ret;
+		}
+	}
+
+	mt9v022->switch_gpio = gpio;
+#else
+	mt9v022->switch_gpio = NO_GPIO;
+#endif
+	return 0;
+}
+
+static void bus_switch_release(struct mt9v022 *mt9v022)
+{
+#ifdef CONFIG_MT9V022_PCA9536_SWITCH
+	if (mt9v022->switch_gpio != NO_GPIO)
+		gpio_free(mt9v022->switch_gpio);
+#endif
+}
+
+static int bus_switch_act(struct mt9v022 *mt9v022, int go8bit)
+{
+#ifdef CONFIG_MT9V022_PCA9536_SWITCH
+	if (mt9v022->switch_gpio == NO_GPIO)
+		return -ENODEV;
+
+	gpio_set_value_cansleep(mt9v022->switch_gpio, go8bit);
+	return 0;
+#else
+	return -ENODEV;
+#endif
+}
+
+static int mt9v022_set_capture_format(struct soc_camera_device *icd,
+		__u32 pixfmt, struct v4l2_rect *rect, unsigned int flags)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+	unsigned int width_flag = flags & (IS_DATAWIDTH_10 | IS_DATAWIDTH_9 |
+					   IS_DATAWIDTH_8);
+	u16 pixclk = 0;
+	int ret;
+
+	/* Only one width bit may be set */
+	if (!is_power_of_2(width_flag))
+		return -EINVAL;
+
+	/* The caller provides a supported format, as verified per call to
+	 * icd->try_fmt_cap(), datawidth is from our supported format list */
+	switch (pixfmt) {
+	case V4L2_PIX_FMT_GREY:
+	case V4L2_PIX_FMT_Y16:
+		if (mt9v022->model != V4L2_IDENT_MT9V022IX7ATM)
+			return -EINVAL;
+		break;
+	case V4L2_PIX_FMT_SBGGR8:
+	case V4L2_PIX_FMT_SBGGR16:
+		if (mt9v022->model != V4L2_IDENT_MT9V022IX7ATC)
+			return -EINVAL;
+		break;
+	case 0:
+		/* No format change, only geometry */
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* Like in example app. Contradicts the datasheet though */
+	ret = reg_read(icd, MT9V022_AEC_AGC_ENABLE);
+	if (ret >= 0) {
+		if (ret & 1) /* Autoexposure */
+			ret = reg_write(icd, MT9V022_MAX_TOTAL_SHUTTER_WIDTH,
+					rect->height + icd->y_skip_top + 43);
+		else
+			ret = reg_write(icd, MT9V022_TOTAL_SHUTTER_WIDTH,
+					rect->height + icd->y_skip_top + 43);
+	}
+	/* Setup frame format: defaults apart from width and height */
+	if (ret >= 0)
+		ret = reg_write(icd, MT9V022_COLUMN_START, rect->left);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9V022_ROW_START, rect->top);
+	if (ret >= 0)
+		/* Default 94, Phytec driver says:
+		 * "width + horizontal blank >= 660" */
+		ret = reg_write(icd, MT9V022_HORIZONTAL_BLANKING,
+				rect->width > 660 - 43 ? 43 :
+				660 - rect->width);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9V022_VERTICAL_BLANKING, 45);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9V022_WINDOW_WIDTH, rect->width);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9V022_WINDOW_HEIGHT,
+				rect->height + icd->y_skip_top);
+
+	if (ret < 0)
+		return ret;
+
+	dev_dbg(&icd->dev, "Frame %ux%u pixel\n", rect->width, rect->height);
+
+	if ((mt9v022->datawidth != 10 && (width_flag == IS_DATAWIDTH_10)) ||
+	    (mt9v022->datawidth != 9  && (width_flag == IS_DATAWIDTH_9)) ||
+	    (mt9v022->datawidth != 8  && (width_flag == IS_DATAWIDTH_8))) {
+		/* data width switch requested */
+		if (mt9v022->switch_gpio == NO_GPIO)
+			return -EINVAL;
+
+		/* Well, we actually only can do 10 or 8 bits... */
+		if (width_flag == IS_DATAWIDTH_9)
+			return -EINVAL;
+
+		ret = bus_switch_act(mt9v022,
+				     width_flag == IS_DATAWIDTH_8);
+		if (ret < 0)
+			return ret;
+
+		mt9v022->datawidth = width_flag == IS_DATAWIDTH_8 ? 8 : 10;
+	}
+
+	if (flags & IS_PCLK_SAMPLE_RISING)
+		pixclk |= 0x10;
+
+	if (!(flags & IS_HSYNC_ACTIVE_HIGH))
+		pixclk |= 0x1;
+
+	if (!(flags & IS_VSYNC_ACTIVE_HIGH))
+		pixclk |= 0x2;
+
+	ret = reg_write(icd, MT9V022_PIXCLK_FV_LV, pixclk);
+	if (ret < 0)
+		return ret;
+
+	if (!(flags & IS_MASTER))
+		mt9v022->chip_control &= ~0x8;
+
+	ret = reg_write(icd, MT9V022_CHIP_CONTROL, mt9v022->chip_control);
+	if (ret < 0)
+		return ret;
+
+	dev_dbg(&icd->dev, "Calculated pixclk 0x%x, chip control 0x%x\n",
+		pixclk, mt9v022->chip_control);
+
+	return 0;
+}
+
+static int mt9v022_try_fmt_cap(struct soc_camera_device *icd,
+			       struct v4l2_format *f)
+{
+	if (f->fmt.pix.height < 32 + icd->y_skip_top)
+		f->fmt.pix.height = 32 + icd->y_skip_top;
+	if (f->fmt.pix.height > 480 + icd->y_skip_top)
+		f->fmt.pix.height = 480 + icd->y_skip_top;
+	if (f->fmt.pix.width < 48)
+		f->fmt.pix.width = 48;
+	if (f->fmt.pix.width > 752)
+		f->fmt.pix.width = 752;
+	f->fmt.pix.width &= ~0x03; /* ? */
+
+	return 0;
+}
+
+static int mt9v022_get_chip_id(struct soc_camera_device *icd,
+			       struct v4l2_chip_ident *id)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+
+	if (id->match_type != V4L2_CHIP_MATCH_I2C_ADDR)
+		return -EINVAL;
+
+	if (id->match_chip != mt9v022->client->addr)
+		return -ENODEV;
+
+	id->ident	= mt9v022->model;
+	id->revision	= 0;
+
+	return 0;
+}
+
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+static int mt9v022_get_register(struct soc_camera_device *icd,
+				struct v4l2_register *reg)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+
+	if (reg->match_type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
+		return -EINVAL;
+
+	if (reg->match_chip != mt9v022->client->addr)
+		return -ENODEV;
+
+	reg->val = reg_read(icd, reg->reg);
+
+	if (reg->val > 0xffff)
+		return -EIO;
+
+	return 0;
+}
+
+static int mt9v022_set_register(struct soc_camera_device *icd,
+				struct v4l2_register *reg)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+
+	if (reg->match_type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
+		return -EINVAL;
+
+	if (reg->match_chip != mt9v022->client->addr)
+		return -ENODEV;
+
+	if (reg_write(icd, reg->reg, reg->val) < 0)
+		return -EIO;
+
+	return 0;
+}
+#endif
+
+static unsigned int mt9v022_get_datawidth(struct soc_camera_device *icd)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+	return mt9v022->datawidth;
+}
+
+const struct v4l2_queryctrl mt9v022_controls[] = {
+	{
+		.id		= V4L2_CID_VFLIP,
+		.type		= V4L2_CTRL_TYPE_BOOLEAN,
+		.name		= "Flip Vertically",
+		.minimum	= 0,
+		.maximum	= 1,
+		.step		= 1,
+		.default_value	= 0,
+	}, {
+		.id		= V4L2_CID_HFLIP,
+		.type		= V4L2_CTRL_TYPE_BOOLEAN,
+		.name		= "Flip Horizontally",
+		.minimum	= 0,
+		.maximum	= 1,
+		.step		= 1,
+		.default_value	= 0,
+	}, {
+		.id		= V4L2_CID_GAIN,
+		.type		= V4L2_CTRL_TYPE_INTEGER,
+		.name		= "Analog Gain",
+		.minimum	= 64,
+		.maximum	= 127,
+		.step		= 1,
+		.default_value	= 64,
+		.flags		= V4L2_CTRL_FLAG_SLIDER,
+	}, {
+		.id		= V4L2_CID_EXPOSURE,
+		.type		= V4L2_CTRL_TYPE_INTEGER,
+		.name		= "Exposure",
+		.minimum	= 1,
+		.maximum	= 255,
+		.step		= 1,
+		.default_value	= 255,
+		.flags		= V4L2_CTRL_FLAG_SLIDER,
+	}, {
+		.id		= V4L2_CID_AUTOGAIN,
+		.type		= V4L2_CTRL_TYPE_BOOLEAN,
+		.name		= "Automatic Gain",
+		.minimum	= 0,
+		.maximum	= 1,
+		.step		= 1,
+		.default_value	= 1,
+	}, {
+		.id		= V4L2_CID_EXPOSURE_AUTO,
+		.type		= V4L2_CTRL_TYPE_BOOLEAN,
+		.name		= "Automatic Exposure",
+		.minimum	= 0,
+		.maximum	= 1,
+		.step		= 1,
+		.default_value	= 1,
+	}
+};
+
+static int mt9v022_get_control(struct soc_camera_device *icd,
+			       struct v4l2_control *ctrl);
+static int mt9v022_set_control(struct soc_camera_device *icd,
+			       struct v4l2_control *ctrl);
+
+static struct soc_camera_ops mt9v022_ops = {
+	.owner			= THIS_MODULE,
+	.init			= mt9v022_init,
+	.release		= mt9v022_release,
+	.start_capture		= mt9v022_start_capture,
+	.stop_capture		= mt9v022_stop_capture,
+	.set_capture_format	= mt9v022_set_capture_format,
+	.try_fmt_cap		= mt9v022_try_fmt_cap,
+	.formats		= mt9v022_formats,
+	.num_formats		= ARRAY_SIZE(mt9v022_formats),
+	.get_datawidth		= mt9v022_get_datawidth,
+	.controls		= mt9v022_controls,
+	.num_controls		= ARRAY_SIZE(mt9v022_controls),
+	.get_control		= mt9v022_get_control,
+	.set_control		= mt9v022_set_control,
+	.get_chip_id		= mt9v022_get_chip_id,
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+	.get_register		= mt9v022_get_register,
+	.set_register		= mt9v022_set_register,
+#endif
+};
+
+static int mt9v022_get_control(struct soc_camera_device *icd,
+			       struct v4l2_control *ctrl)
+{
+	int data;
+
+	switch (ctrl->id) {
+	case V4L2_CID_VFLIP:
+		data = reg_read(icd, MT9V022_READ_MODE);
+		if (data < 0)
+			return -EIO;
+		ctrl->value = !!(data & 0x10);
+		break;
+	case V4L2_CID_HFLIP:
+		data = reg_read(icd, MT9V022_READ_MODE);
+		if (data < 0)
+			return -EIO;
+		ctrl->value = !!(data & 0x20);
+		break;
+	case V4L2_CID_EXPOSURE_AUTO:
+		data = reg_read(icd, MT9V022_AEC_AGC_ENABLE);
+		if (data < 0)
+			return -EIO;
+		ctrl->value = !!(data & 0x1);
+		break;
+	case V4L2_CID_AUTOGAIN:
+		data = reg_read(icd, MT9V022_AEC_AGC_ENABLE);
+		if (data < 0)
+			return -EIO;
+		ctrl->value = !!(data & 0x2);
+		break;
+	}
+	return 0;
+}
+
+static int mt9v022_set_control(struct soc_camera_device *icd,
+			       struct v4l2_control *ctrl)
+{
+	int data;
+	const struct v4l2_queryctrl *qctrl;
+
+	qctrl = soc_camera_find_qctrl(&mt9v022_ops, ctrl->id);
+
+	if (!qctrl)
+		return -EINVAL;
+
+	switch (ctrl->id) {
+	case V4L2_CID_VFLIP:
+		if (ctrl->value)
+			data = reg_set(icd, MT9V022_READ_MODE, 0x10);
+		else
+			data = reg_clear(icd, MT9V022_READ_MODE, 0x10);
+		if (data < 0)
+			return -EIO;
+		break;
+	case V4L2_CID_HFLIP:
+		if (ctrl->value)
+			data = reg_set(icd, MT9V022_READ_MODE, 0x20);
+		else
+			data = reg_clear(icd, MT9V022_READ_MODE, 0x20);
+		if (data < 0)
+			return -EIO;
+		break;
+	case V4L2_CID_GAIN:
+		/* mt9v022 has minimum == default */
+		if (ctrl->value > qctrl->maximum || ctrl->value < qctrl->minimum)
+			return -EINVAL;
+		else {
+			unsigned long range = qctrl->maximum - qctrl->minimum;
+			/* Datasheet says 16 to 64. autogain only works properly
+			 * after setting gain to maximum 14. Larger values
+			 * produce "white fly" noise effect. On the whole,
+			 * manually setting analog gain does no good. */
+			unsigned long gain = ((ctrl->value - qctrl->minimum) *
+					      10 + range / 2) / range + 4;
+			if (gain >= 32)
+				gain &= ~1;
+			/* The user wants to set gain manually, hope, she
+			 * knows, what she's doing... Switch AGC off. */
+
+			if (reg_clear(icd, MT9V022_AEC_AGC_ENABLE, 0x2) < 0)
+				return -EIO;
+
+			dev_info(&icd->dev, "Setting gain from %d to %lu\n",
+				 reg_read(icd, MT9V022_ANALOG_GAIN), gain);
+			if (reg_write(icd, MT9V022_ANALOG_GAIN, gain) < 0)
+				return -EIO;
+			icd->gain = ctrl->value;
+		}
+		break;
+	case V4L2_CID_EXPOSURE:
+		/* mt9v022 has maximum == default */
+		if (ctrl->value > qctrl->maximum || ctrl->value < qctrl->minimum)
+			return -EINVAL;
+		else {
+			unsigned long range = qctrl->maximum - qctrl->minimum;
+			unsigned long shutter = ((ctrl->value - qctrl->minimum) *
+						 479 + range / 2) / range + 1;
+			/* The user wants to set shutter width manually, hope,
+			 * she knows, what she's doing... Switch AEC off. */
+
+			if (reg_clear(icd, MT9V022_AEC_AGC_ENABLE, 0x1) < 0)
+				return -EIO;
+
+			dev_dbg(&icd->dev, "Shutter width from %d to %lu\n",
+				reg_read(icd, MT9V022_TOTAL_SHUTTER_WIDTH),
+				shutter);
+			if (reg_write(icd, MT9V022_TOTAL_SHUTTER_WIDTH,
+				      shutter) < 0)
+				return -EIO;
+			icd->exposure = ctrl->value;
+		}
+		break;
+	case V4L2_CID_AUTOGAIN:
+		if (ctrl->value)
+			data = reg_set(icd, MT9V022_AEC_AGC_ENABLE, 0x2);
+		else
+			data = reg_clear(icd, MT9V022_AEC_AGC_ENABLE, 0x2);
+		if (data < 0)
+			return -EIO;
+		break;
+	case V4L2_CID_EXPOSURE_AUTO:
+		if (ctrl->value)
+			data = reg_set(icd, MT9V022_AEC_AGC_ENABLE, 0x1);
+		else
+			data = reg_clear(icd, MT9V022_AEC_AGC_ENABLE, 0x1);
+		if (data < 0)
+			return -EIO;
+		break;
+	}
+	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 mt9v022_video_probe(struct soc_camera_device *icd)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+	s32 data;
+	int ret;
+
+	if (!icd->dev.parent ||
+	    to_soc_camera_host(icd->dev.parent)->nr != icd->iface)
+		return -ENODEV;
+
+	/* Read out the chip version register */
+	data = reg_read(icd, MT9V022_CHIP_VERSION);
+
+	/* must be 0x1311 or 0x1313 */
+	if (data != 0x1311 && data != 0x1313) {
+		ret = -ENODEV;
+		dev_info(&icd->dev, "No MT9V022 detected, ID register 0x%x\n",
+			 data);
+		goto ei2c;
+	}
+
+	/* Soft reset */
+	ret = reg_write(icd, MT9V022_RESET, 1);
+	if (ret < 0)
+		goto ei2c;
+	/* 15 clock cycles */
+	udelay(200);
+	if (reg_read(icd, MT9V022_RESET)) {
+		dev_err(&icd->dev, "Resetting MT9V022 failed!\n");
+		goto ei2c;
+	}
+
+	/* Set monochrome or colour sensor type */
+	if (sensor_type && (!strcmp("colour", sensor_type) ||
+			    !strcmp("color", sensor_type))) {
+		ret = reg_write(icd, MT9V022_PIXEL_OPERATION_MODE, 4 | 0x11);
+		mt9v022->model = V4L2_IDENT_MT9V022IX7ATC;
+	} else {
+		ret = reg_write(icd, MT9V022_PIXEL_OPERATION_MODE, 0x11);
+		mt9v022->model = V4L2_IDENT_MT9V022IX7ATM;
+	}
+
+	if (ret >= 0)
+		ret = soc_camera_video_start(icd);
+	if (ret < 0)
+		goto eisis;
+
+	dev_info(&icd->dev, "Detected a MT9V022 chip ID %x, %s sensor\n",
+		 data, mt9v022->model == V4L2_IDENT_MT9V022IX7ATM ?
+		 "monochrome" : "colour");
+
+	return 0;
+
+eisis:
+ei2c:
+	return ret;
+}
+
+static void mt9v022_video_remove(struct soc_camera_device *icd)
+{
+	struct mt9v022 *mt9v022 = container_of(icd, struct mt9v022, icd);
+
+	dev_dbg(&icd->dev, "Video %x removed: %p, %p\n", mt9v022->client->addr,
+		mt9v022->icd.dev.parent, mt9v022->icd.vdev);
+	soc_camera_video_stop(&mt9v022->icd);
+}
+
+static int mt9v022_probe(struct i2c_client *client)
+{
+	struct mt9v022 *mt9v022;
+	struct soc_camera_device *icd;
+	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+	struct soc_camera_link *icl = client->dev.platform_data;
+	int ret;
+
+	if (!icl) {
+		dev_err(&client->dev, "MT9V022 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;
+	}
+
+	mt9v022 = kzalloc(sizeof(struct mt9v022), GFP_KERNEL);
+	if (!mt9v022)
+		return -ENOMEM;
+
+	mt9v022->chip_control = MT9V022_CHIP_CONTROL_DEFAULT;
+	mt9v022->client = client;
+	i2c_set_clientdata(client, mt9v022);
+
+	icd = &mt9v022->icd;
+	icd->probe	= mt9v022_video_probe;
+	icd->remove	= mt9v022_video_remove;
+	icd->ops	= &mt9v022_ops;
+	icd->control	= &client->dev;
+	icd->x_min	= 1;
+	icd->y_min	= 4;
+	icd->x_current	= 1;
+	icd->y_current	= 4;
+	icd->width_min	= 48;
+	icd->width_max	= 752;
+	icd->height_min	= 32;
+	icd->height_max	= 480;
+	icd->y_skip_top	= 1;
+	icd->iface	= icl->bus_id;
+	/* Default datawidth - this is the only width this camera (normally)
+	 * supports. It is only with extra logic that it can support
+	 * other widths. Therefore it seems to be a sensible default. */
+	mt9v022->datawidth = 10;
+
+	ret = bus_switch_request(mt9v022, icl);
+	if (ret)
+		goto eswinit;
+
+	ret = soc_camera_device_register(icd);
+	if (ret)
+		goto eisdr;
+
+	return 0;
+
+eisdr:
+	bus_switch_release(mt9v022);
+eswinit:
+	kfree(mt9v022);
+	return ret;
+}
+
+static int mt9v022_remove(struct i2c_client *client)
+{
+	struct mt9v022 *mt9v022 = i2c_get_clientdata(client);
+
+	soc_camera_device_unregister(&mt9v022->icd);
+	bus_switch_release(mt9v022);
+	kfree(mt9v022);
+
+	return 0;
+}
+
+static struct i2c_driver mt9v022_i2c_driver = {
+	.driver = {
+		.name = "mt9v022",
+	},
+	.probe		= mt9v022_probe,
+	.remove		= mt9v022_remove,
+};
+
+static int __init mt9v022_mod_init(void)
+{
+	return i2c_add_driver(&mt9v022_i2c_driver);
+}
+
+static void __exit mt9v022_mod_exit(void)
+{
+	i2c_del_driver(&mt9v022_i2c_driver);
+}
+
+module_init(mt9v022_mod_init);
+module_exit(mt9v022_mod_exit);
+
+MODULE_DESCRIPTION("Micron MT9V022 Camera driver");
+MODULE_AUTHOR("Guennadi Liakhovetski <kernel@pengutronix.de>");
+MODULE_LICENSE("GPL");