V4L/DVB (7173): Add support for the MT9M001 camera

This driver supports Micron MT9M001 monochrome and colour cameras.

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

3 files changed, 710 insertions, 0 deletions

diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
index fb4bf089c68f..393bbf92b100 100644
--- a/drivers/media/video/Kconfig
+++ b/drivers/media/video/Kconfig
@@ -845,6 +845,21 @@ config SOC_CAMERA
 	  over a bus like PCI or USB. For example some i2c camera connected
 	  directly to the data bus of an SoC.
 
+config SOC_CAMERA_MT9M001
+	tristate "mt9m001 support"
+	depends on SOC_CAMERA && GENERIC_GPIO
+	select GPIO_PCA953X if MT9M001_PCA9536_SWITCH
+	help
+	  This driver supports MT9M001 cameras from Micron, monochrome
+	  and colour models.
+
+config MT9M001_PCA9536_SWITCH
+	bool "pca9536 datawidth switch for mt9m001"
+	depends on SOC_CAMERA_MT9M001
+	help
+	  Select this if your MT9M001 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 874ed967f416..9321f68e52a7 100644
--- a/drivers/media/video/Makefile
+++ b/drivers/media/video/Makefile
@@ -138,6 +138,7 @@ 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
 
 EXTRA_CFLAGS += -Idrivers/media/dvb/dvb-core
 EXTRA_CFLAGS += -Idrivers/media/dvb/frontends
diff --git a/drivers/media/video/mt9m001.c b/drivers/media/video/mt9m001.c
new file mode 100644
index 000000000000..3c5867c378d3
--- /dev/null
+++ b/drivers/media/video/mt9m001.c
@@ -0,0 +1,694 @@
+/*
+ * Driver for MT9M001 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/log2.h>
+
+#include <media/v4l2-common.h>
+#include <media/v4l2-chip-ident.h>
+#include <media/soc_camera.h>
+
+#include <asm/gpio.h>
+
+/* mt9m001 i2c address 0x5d
+ * The platform has to define i2c_board_info
+ * and call i2c_register_board_info() */
+
+/* mt9m001 selected register addresses */
+#define MT9M001_CHIP_VERSION		0x00
+#define MT9M001_ROW_START		0x01
+#define MT9M001_COLUMN_START		0x02
+#define MT9M001_WINDOW_HEIGHT		0x03
+#define MT9M001_WINDOW_WIDTH		0x04
+#define MT9M001_HORIZONTAL_BLANKING	0x05
+#define MT9M001_VERTICAL_BLANKING	0x06
+#define MT9M001_OUTPUT_CONTROL		0x07
+#define MT9M001_SHUTTER_WIDTH		0x09
+#define MT9M001_FRAME_RESTART		0x0b
+#define MT9M001_SHUTTER_DELAY		0x0c
+#define MT9M001_RESET			0x0d
+#define MT9M001_READ_OPTIONS1		0x1e
+#define MT9M001_READ_OPTIONS2		0x20
+#define MT9M001_GLOBAL_GAIN		0x35
+#define MT9M001_CHIP_ENABLE		0xF1
+
+static const struct soc_camera_data_format mt9m001_colour_formats[] = {
+	{
+		.name		= "RGB Bayer (sRGB)",
+		.depth		= 16,
+		.fourcc		= V4L2_PIX_FMT_SBGGR8,
+		.colorspace	= V4L2_COLORSPACE_SRGB,
+	}
+};
+
+static const struct soc_camera_data_format mt9m001_monochrome_formats[] = {
+	{
+		.name		= "Monochrome 10 bit",
+		.depth		= 10,
+		.fourcc		= V4L2_PIX_FMT_Y16,
+	}, {
+		.name		= "Monochrome 8 bit",
+		.depth		= 8,
+		.fourcc		= V4L2_PIX_FMT_GREY,
+	},
+};
+
+struct mt9m001 {
+	struct i2c_client *client;
+	struct soc_camera_device icd;
+	int model;	/* V4L2_IDENT_MT9M001* codes from v4l2-chip-ident.h */
+	int switch_gpio;
+	unsigned char autoexposure;
+	unsigned char datawidth;
+};
+
+static int reg_read(struct soc_camera_device *icd, const u8 reg)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+	struct i2c_client *client = mt9m001->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 mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+	return i2c_smbus_write_word_data(mt9m001->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 mt9m001_init(struct soc_camera_device *icd)
+{
+	int ret;
+
+	/* Disable chip, synchronous option update */
+	dev_dbg(icd->vdev->dev, "%s\n", __FUNCTION__);
+
+	ret = reg_write(icd, MT9M001_RESET, 1);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9M001_RESET, 0);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9M001_OUTPUT_CONTROL, 0);
+
+	return ret >= 0 ? 0 : -EIO;
+}
+
+static int mt9m001_release(struct soc_camera_device *icd)
+{
+	/* Disable the chip */
+	reg_write(icd, MT9M001_OUTPUT_CONTROL, 0);
+	return 0;
+}
+
+static int mt9m001_start_capture(struct soc_camera_device *icd)
+{
+	/* Switch to master "normal" mode */
+	if (reg_write(icd, MT9M001_OUTPUT_CONTROL, 2) < 0)
+		return -EIO;
+	return 0;
+}
+
+static int mt9m001_stop_capture(struct soc_camera_device *icd)
+{
+	/* Stop sensor readout */
+	if (reg_write(icd, MT9M001_OUTPUT_CONTROL, 0) < 0)
+		return -EIO;
+	return 0;
+}
+
+static int bus_switch_request(struct mt9m001 *mt9m001,
+			      struct soc_camera_link *icl)
+{
+#ifdef CONFIG_MT9M001_PCA9536_SWITCH
+	int ret;
+	unsigned int gpio = icl->gpio;
+
+	if (gpio != NO_GPIO) {
+		/* We have a data bus switch. */
+		ret = gpio_request(gpio, "mt9m001");
+		if (ret < 0) {
+			dev_err(&mt9m001->client->dev, "Cannot get GPIO %u\n",
+				gpio);
+			return ret;
+		}
+
+		ret = gpio_direction_output(gpio, 0);
+		if (ret < 0) {
+			dev_err(&mt9m001->client->dev,
+				"Cannot set GPIO %u to output\n", gpio);
+			gpio_free(gpio);
+			return ret;
+		}
+	}
+
+	mt9m001->switch_gpio = gpio;
+#else
+	mt9m001->switch_gpio = NO_GPIO;
+#endif
+	return 0;
+}
+
+static void bus_switch_release(struct mt9m001 *mt9m001)
+{
+#ifdef CONFIG_MT9M001_PCA9536_SWITCH
+	if (mt9m001->switch_gpio != NO_GPIO)
+		gpio_free(mt9m001->switch_gpio);
+#endif
+}
+
+static int bus_switch_act(struct mt9m001 *mt9m001, int go8bit)
+{
+#ifdef CONFIG_MT9M001_PCA9536_SWITCH
+	if (mt9m001->switch_gpio == NO_GPIO)
+		return -ENODEV;
+
+	gpio_set_value_cansleep(mt9m001->switch_gpio, go8bit);
+	return 0;
+#else
+	return -ENODEV;
+#endif
+}
+
+static int mt9m001_set_capture_format(struct soc_camera_device *icd,
+		__u32 pixfmt, struct v4l2_rect *rect, unsigned int flags)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+	unsigned int width_flag = flags & (IS_DATAWIDTH_10 | IS_DATAWIDTH_9 |
+					   IS_DATAWIDTH_8);
+	int ret;
+	const u16 hblank = 9, vblank = 25;
+
+	/* MT9M001 has all capture_format parameters fixed */
+	if (!(flags & IS_MASTER) ||
+	    !(flags & IS_PCLK_SAMPLE_RISING) ||
+	    !(flags & IS_HSYNC_ACTIVE_HIGH) ||
+	    !(flags & IS_VSYNC_ACTIVE_HIGH))
+		return -EINVAL;
+
+	/* Only one width bit may be set */
+	if (!is_power_of_2(width_flag))
+		return -EINVAL;
+
+	if ((mt9m001->datawidth != 10 && (width_flag == IS_DATAWIDTH_10)) ||
+	    (mt9m001->datawidth != 9  && (width_flag == IS_DATAWIDTH_9)) ||
+	    (mt9m001->datawidth != 8  && (width_flag == IS_DATAWIDTH_8))) {
+		/* data width switch requested */
+		if (mt9m001->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(mt9m001,
+				     width_flag == IS_DATAWIDTH_8);
+		if (ret < 0)
+			return ret;
+
+		mt9m001->datawidth = width_flag == IS_DATAWIDTH_8 ? 8 : 10;
+	}
+
+	/* Blanking and start values - default... */
+	ret = reg_write(icd, MT9M001_HORIZONTAL_BLANKING, hblank);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9M001_VERTICAL_BLANKING, vblank);
+
+	/* The caller provides a supported format, as verified per
+	 * call to icd->try_fmt_cap() */
+	if (ret >= 0)
+		ret = reg_write(icd, MT9M001_COLUMN_START, rect->left);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9M001_ROW_START, rect->top);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9M001_WINDOW_WIDTH, rect->width - 1);
+	if (ret >= 0)
+		ret = reg_write(icd, MT9M001_WINDOW_HEIGHT,
+				rect->height + icd->y_skip_top - 1);
+	if (ret >= 0 && mt9m001->autoexposure) {
+		ret = reg_write(icd, MT9M001_SHUTTER_WIDTH,
+				rect->height + icd->y_skip_top + vblank);
+		if (ret >= 0) {
+			const struct v4l2_queryctrl *qctrl =
+				soc_camera_find_qctrl(icd->ops,
+						      V4L2_CID_EXPOSURE);
+			icd->exposure = (524 + (rect->height + icd->y_skip_top +
+						vblank - 1) *
+					 (qctrl->maximum - qctrl->minimum)) /
+				1048 + qctrl->minimum;
+		}
+	}
+
+	return ret < 0 ? ret : 0;
+}
+
+static int mt9m001_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 > 1024 + icd->y_skip_top)
+		f->fmt.pix.height = 1024 + icd->y_skip_top;
+	if (f->fmt.pix.width < 48)
+		f->fmt.pix.width = 48;
+	if (f->fmt.pix.width > 1280)
+		f->fmt.pix.width = 1280;
+	f->fmt.pix.width &= ~0x01; /* has to be even, unsure why was ~3 */
+
+	return 0;
+}
+
+static int mt9m001_get_chip_id(struct soc_camera_device *icd,
+			       struct v4l2_chip_ident *id)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+
+	if (id->match_type != V4L2_CHIP_MATCH_I2C_ADDR)
+		return -EINVAL;
+
+	if (id->match_chip != mt9m001->client->addr)
+		return -ENODEV;
+
+	id->ident	= mt9m001->model;
+	id->revision	= 0;
+
+	return 0;
+}
+
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+static int mt9m001_get_register(struct soc_camera_device *icd,
+				struct v4l2_register *reg)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+
+	if (reg->match_type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
+		return -EINVAL;
+
+	if (reg->match_chip != mt9m001->client->addr)
+		return -ENODEV;
+
+	reg->val = reg_read(icd, reg->reg);
+
+	if (reg->val > 0xffff)
+		return -EIO;
+
+	return 0;
+}
+
+static int mt9m001_set_register(struct soc_camera_device *icd,
+				struct v4l2_register *reg)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+
+	if (reg->match_type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
+		return -EINVAL;
+
+	if (reg->match_chip != mt9m001->client->addr)
+		return -ENODEV;
+
+	if (reg_write(icd, reg->reg, reg->val) < 0)
+		return -EIO;
+
+	return 0;
+}
+#endif
+
+static unsigned int mt9m001_get_datawidth(struct soc_camera_device *icd)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+	return mt9m001->datawidth;
+}
+
+const struct v4l2_queryctrl mt9m001_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_GAIN,
+		.type		= V4L2_CTRL_TYPE_INTEGER,
+		.name		= "Gain",
+		.minimum	= 0,
+		.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_EXPOSURE_AUTO,
+		.type		= V4L2_CTRL_TYPE_BOOLEAN,
+		.name		= "Automatic Exposure",
+		.minimum	= 0,
+		.maximum	= 1,
+		.step		= 1,
+		.default_value	= 1,
+	}
+};
+
+static int mt9m001_get_control(struct soc_camera_device *icd, struct v4l2_control *ctrl);
+static int mt9m001_set_control(struct soc_camera_device *icd, struct v4l2_control *ctrl);
+
+static struct soc_camera_ops mt9m001_ops = {
+	.owner			= THIS_MODULE,
+	.init			= mt9m001_init,
+	.release		= mt9m001_release,
+	.start_capture		= mt9m001_start_capture,
+	.stop_capture		= mt9m001_stop_capture,
+	.set_capture_format	= mt9m001_set_capture_format,
+	.try_fmt_cap		= mt9m001_try_fmt_cap,
+	.formats		= NULL, /* Filled in later depending on the */
+	.num_formats		= 0,	/* camera type and data widths */
+	.get_datawidth		= mt9m001_get_datawidth,
+	.controls		= mt9m001_controls,
+	.num_controls		= ARRAY_SIZE(mt9m001_controls),
+	.get_control		= mt9m001_get_control,
+	.set_control		= mt9m001_set_control,
+	.get_chip_id		= mt9m001_get_chip_id,
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+	.get_register		= mt9m001_get_register,
+	.set_register		= mt9m001_set_register,
+#endif
+};
+
+static int mt9m001_get_control(struct soc_camera_device *icd, struct v4l2_control *ctrl)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+	int data;
+
+	switch (ctrl->id) {
+	case V4L2_CID_VFLIP:
+		data = reg_read(icd, MT9M001_READ_OPTIONS2);
+		if (data < 0)
+			return -EIO;
+		ctrl->value = !!(data & 0x8000);
+		break;
+	case V4L2_CID_EXPOSURE_AUTO:
+		ctrl->value = mt9m001->autoexposure;
+		break;
+	}
+	return 0;
+}
+
+static int mt9m001_set_control(struct soc_camera_device *icd, struct v4l2_control *ctrl)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+	const struct v4l2_queryctrl *qctrl;
+	int data;
+
+	qctrl = soc_camera_find_qctrl(&mt9m001_ops, ctrl->id);
+
+	if (!qctrl)
+		return -EINVAL;
+
+	switch (ctrl->id) {
+	case V4L2_CID_VFLIP:
+		if (ctrl->value)
+			data = reg_set(icd, MT9M001_READ_OPTIONS2, 0x8000);
+		else
+			data = reg_clear(icd, MT9M001_READ_OPTIONS2, 0x8000);
+		if (data < 0)
+			return -EIO;
+		break;
+	case V4L2_CID_GAIN:
+		if (ctrl->value > qctrl->maximum || ctrl->value < qctrl->minimum)
+			return -EINVAL;
+		/* See Datasheet Table 7, Gain settings. */
+		if (ctrl->value <= qctrl->default_value) {
+			/* Pack it into 0..1 step 0.125, register values 0..8 */
+			unsigned long range = qctrl->default_value - qctrl->minimum;
+			data = ((ctrl->value - qctrl->minimum) * 8 + range / 2) / range;
+
+			dev_dbg(&icd->dev, "Setting gain %d\n", data);
+			data = reg_write(icd, MT9M001_GLOBAL_GAIN, data);
+			if (data < 0)
+				return -EIO;
+		} else {
+			/* Pack it into 1.125..15 variable step, register values 9..67 */
+			/* We assume qctrl->maximum - qctrl->default_value - 1 > 0 */
+			unsigned long range = qctrl->maximum - qctrl->default_value - 1;
+			unsigned long gain = ((ctrl->value - qctrl->default_value - 1) *
+					       111 + range / 2) / range + 9;
+
+			if (gain <= 32)
+				data = gain;
+			else if (gain <= 64)
+				data = ((gain - 32) * 16 + 16) / 32 + 80;
+			else
+				data = ((gain - 64) * 7 + 28) / 56 + 96;
+
+			dev_dbg(&icd->dev, "Setting gain from %d to %d\n",
+				 reg_read(icd, MT9M001_GLOBAL_GAIN), data);
+			data = reg_write(icd, MT9M001_GLOBAL_GAIN, data);
+			if (data < 0)
+				return -EIO;
+		}
+
+		/* Success */
+		icd->gain = ctrl->value;
+		break;
+	case V4L2_CID_EXPOSURE:
+		/* mt9m001 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) * 1048 +
+						 range / 2) / range + 1;
+
+			dev_dbg(&icd->dev, "Setting shutter width from %d to %lu\n",
+				 reg_read(icd, MT9M001_SHUTTER_WIDTH), shutter);
+			if (reg_write(icd, MT9M001_SHUTTER_WIDTH, shutter) < 0)
+				return -EIO;
+			icd->exposure = ctrl->value;
+			mt9m001->autoexposure = 0;
+		}
+		break;
+	case V4L2_CID_EXPOSURE_AUTO:
+		if (ctrl->value) {
+			const u16 vblank = 25;
+			if (reg_write(icd, MT9M001_SHUTTER_WIDTH, icd->height +
+				      icd->y_skip_top + vblank) < 0)
+				return -EIO;
+			qctrl = soc_camera_find_qctrl(icd->ops, V4L2_CID_EXPOSURE);
+			icd->exposure = (524 + (icd->height + icd->y_skip_top + vblank - 1) *
+					 (qctrl->maximum - qctrl->minimum)) /
+				1048 + qctrl->minimum;
+			mt9m001->autoexposure = 1;
+		} else
+			mt9m001->autoexposure = 0;
+		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 mt9m001_video_probe(struct soc_camera_device *icd)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+	s32 data;
+	int ret;
+
+	/* We must have a parent by now. And it cannot be a wrong one.
+	 * So this entire test is completely redundant. */
+	if (!icd->dev.parent ||
+	    to_soc_camera_host(icd->dev.parent)->nr != icd->iface)
+		return -ENODEV;
+
+	/* Enable the chip */
+	data = reg_write(&mt9m001->icd, MT9M001_CHIP_ENABLE, 1);
+	dev_dbg(&icd->dev, "write: %d\n", data);
+
+	/* Read out the chip version register */
+	data = reg_read(icd, MT9M001_CHIP_VERSION);
+
+	/* must be 0x8411 or 0x8421 for colour sensor and 8431 for bw */
+	switch (data) {
+	case 0x8411:
+	case 0x8421:
+		mt9m001->model = V4L2_IDENT_MT9M001C12ST;
+		mt9m001_ops.formats = mt9m001_colour_formats;
+		mt9m001_ops.num_formats = ARRAY_SIZE(mt9m001_colour_formats);
+		break;
+	case 0x8431:
+		mt9m001->model = V4L2_IDENT_MT9M001C12STM;
+		mt9m001_ops.formats = mt9m001_monochrome_formats;
+		if (mt9m001->client->dev.platform_data)
+			mt9m001_ops.num_formats = ARRAY_SIZE(mt9m001_monochrome_formats);
+		else
+			mt9m001_ops.num_formats = 1;
+		break;
+	default:
+		ret = -ENODEV;
+		dev_err(&icd->dev,
+			"No MT9M001 chip detected, register read %x\n", data);
+		goto ei2c;
+	}
+
+	dev_info(&icd->dev, "Detected a MT9M001 chip ID %x (%s)\n", data,
+		 data == 0x8431 ? "C12STM" : "C12ST");
+
+	/* Now that we know the model, we can start video */
+	ret = soc_camera_video_start(icd);
+	if (ret)
+		goto eisis;
+
+	return 0;
+
+eisis:
+ei2c:
+	return ret;
+}
+
+static void mt9m001_video_remove(struct soc_camera_device *icd)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+
+	dev_dbg(&icd->dev, "Video %x removed: %p, %p\n", mt9m001->client->addr,
+		mt9m001->icd.dev.parent, mt9m001->icd.vdev);
+	soc_camera_video_stop(&mt9m001->icd);
+}
+
+static int mt9m001_probe(struct i2c_client *client)
+{
+	struct mt9m001 *mt9m001;
+	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, "MT9M001 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;
+	}
+
+	mt9m001 = kzalloc(sizeof(struct mt9m001), GFP_KERNEL);
+	if (!mt9m001)
+		return -ENOMEM;
+
+	mt9m001->client = client;
+	i2c_set_clientdata(client, mt9m001);
+
+	/* Second stage probe - when a capture adapter is there */
+	icd = &mt9m001->icd;
+	icd->probe	= mt9m001_video_probe;
+	icd->remove	= mt9m001_video_remove;
+	icd->ops	= &mt9m001_ops;
+	icd->control	= &client->dev;
+	icd->x_min	= 20;
+	icd->y_min	= 12;
+	icd->x_current	= 20;
+	icd->y_current	= 12;
+	icd->width_min	= 48;
+	icd->width_max	= 1280;
+	icd->height_min	= 32;
+	icd->height_max	= 1024;
+	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. */
+	mt9m001->datawidth = 10;
+	/* Simulated autoexposure. If enabled, we calculate shutter width
+	 * ourselves in the driver based on vertical blanking and frame width */
+	mt9m001->autoexposure = 1;
+
+	ret = bus_switch_request(mt9m001, icl);
+	if (ret)
+		goto eswinit;
+
+	ret = soc_camera_device_register(icd);
+	if (ret)
+		goto eisdr;
+
+	return 0;
+
+eisdr:
+	bus_switch_release(mt9m001);
+eswinit:
+	kfree(mt9m001);
+	return ret;
+}
+
+static int mt9m001_remove(struct i2c_client *client)
+{
+	struct mt9m001 *mt9m001 = i2c_get_clientdata(client);
+
+	soc_camera_device_unregister(&mt9m001->icd);
+	bus_switch_release(mt9m001);
+	kfree(mt9m001);
+
+	return 0;
+}
+
+static struct i2c_driver mt9m001_i2c_driver = {
+	.driver = {
+		.name = "mt9m001",
+	},
+	.probe		= mt9m001_probe,
+	.remove		= mt9m001_remove,
+};
+
+static int __init mt9m001_mod_init(void)
+{
+	return i2c_add_driver(&mt9m001_i2c_driver);
+}
+
+static void __exit mt9m001_mod_exit(void)
+{
+	i2c_del_driver(&mt9m001_i2c_driver);
+}
+
+module_init(mt9m001_mod_init);
+module_exit(mt9m001_mod_exit);
+
+MODULE_DESCRIPTION("Micron MT9M001 Camera driver");
+MODULE_AUTHOR("Guennadi Liakhovetski <kernel@pengutronix.de>");
+MODULE_LICENSE("GPL");