[PATCH v4] v4l: Add driver for Micron MT9M032 camera sensor

[Martin Hostettler <martin@neutronstar.dyndns.org>]

The MT9M032 is a parallel 1.6MP sensor from Micron controlled through I2C.

The driver creates a V4L2 subdevice. It currently supports cropping, gain,
exposure and v/h flipping controls in monochrome mode with an
external pixel clock.

Signed-off-by: Martin Hostettler <martin@neutronstar.dyndns.org>
---
 drivers/media/video/Kconfig   |    7 +
 drivers/media/video/Makefile  |    1 +
 drivers/media/video/mt9m032.c |  837 +++++++++++++++++++++++++++++++++++++++++
 include/media/mt9m032.h       |   38 ++
 4 files changed, 883 insertions(+), 0 deletions(-)
 create mode 100644 drivers/media/video/mt9m032.c
 create mode 100644 include/media/mt9m032.h


Changes in V4
 * Use register(-value) constants from MT9P031 to fill in gaps
 * Use MT9M032_CHIP_VERSION_VALUE instead of magical number
 * Use i2c_smbus_{read,write}_word_swapped
 * Minor error return code handling fixes

Changes in V3
 * rebased to current mainline
 * removed unneeded includes
 * remove all translation code to hide black or active boundry sensor pixels. Userspace now needs to select
crop in original device coordinates.
 * remove useless consts, casts and defines
 * changed enum_frame_size to return min == max
 * removed duplicated input validation
 * validate crop rectangle on set_crop

Changes in V2
 * ported to current mainline
 * Moved dispatching for subdev ioctls VIDIOC_DBG_G_REGISTER and VIDIOC_DBG_S_REGISTER into v4l2-subdev
 * Removed VIDIOC_DBG_G_CHIP_IDENT support
 * moved header to media/
 * Fixed missing error handling
 * lowercase hex constants
 * moved v4l2_get_subdevdata to register access helpers
 * use div_u64 instead of do_div
 * moved all know register values into #define:ed constants
 * Fixed error reporting, used clamp instead of open coding.
 * lots of style fixes.
 * add try_ctrl to make sure user space sees rounded values
 * Fixed some problem in control framework usage.
 * Fixed set_format to force width and height setup via crop. Simplyfied code.

diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
index b303a3f..cf05d9b 100644
--- a/drivers/media/video/Kconfig
+++ b/drivers/media/video/Kconfig
@@ -820,6 +820,13 @@ config SOC_CAMERA_MT9M001
 	  This driver supports MT9M001 cameras from Micron, monochrome
 	  and colour models.
 
+config VIDEO_MT9M032
+	tristate "MT9M032 camera sensor support"
+	depends on I2C && VIDEO_V4L2
+	help
+	  This driver supports MT9M032 cameras from Micron, monochrome
+	  models only.
+
 config SOC_CAMERA_MT9M111
 	tristate "mt9m111, mt9m112 and mt9m131 support"
 	depends on SOC_CAMERA && I2C
diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile
index 117f9c4..39c7455 100644
--- a/drivers/media/video/Makefile
+++ b/drivers/media/video/Makefile
@@ -77,6 +77,7 @@ obj-$(CONFIG_VIDEO_ADP1653)	+= adp1653.o
 
 obj-$(CONFIG_SOC_CAMERA_IMX074)		+= imx074.o
 obj-$(CONFIG_SOC_CAMERA_MT9M001)	+= mt9m001.o
+obj-$(CONFIG_VIDEO_MT9M032)             += mt9m032.o
 obj-$(CONFIG_SOC_CAMERA_MT9M111)	+= mt9m111.o
 obj-$(CONFIG_SOC_CAMERA_MT9T031)	+= mt9t031.o
 obj-$(CONFIG_SOC_CAMERA_MT9T112)	+= mt9t112.o
diff --git a/drivers/media/video/mt9m032.c b/drivers/media/video/mt9m032.c
new file mode 100644
index 0000000..6f1968a
--- /dev/null
+++ b/drivers/media/video/mt9m032.c
@@ -0,0 +1,837 @@
+/*
+ * Driver for MT9M032 CMOS Image Sensor from Micron
+ *
+ * Copyright (C) 2010-2011 Lund Engineering
+ * Contact: Gil Lund <gwlund@lundeng.com>
+ * Author: Martin Hostettler <martin@neutronstar.dyndns.org>
+ *
+ * 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/delay.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/v4l2-mediabus.h>
+
+#include <media/media-entity.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-subdev.h>
+
+#include <media/mt9m032.h>
+
+#define MT9M032_CHIP_VERSION			0x00
+#define     MT9M032_CHIP_VERSION_VALUE		0x1402
+#define MT9M032_ROW_START			0x01
+#define MT9M032_COLUMN_START			0x02
+#define MT9M032_ROW_SIZE			0x03
+#define MT9M032_COLUMN_SIZE			0x04
+#define MT9M032_HBLANK				0x05
+#define MT9M032_VBLANK				0x06
+#define MT9M032_SHUTTER_WIDTH_HIGH		0x08
+#define MT9M032_SHUTTER_WIDTH_LOW		0x09
+#define MT9M032_PIX_CLK_CTRL			0x0a
+#define     MT9M032_PIX_CLK_CTRL_INV_PIXCLK	0x8000
+#define MT9M032_RESTART				0x0b
+#define MT9M032_RESET				0x0d
+#define MT9M032_PLL_CONFIG1			0x11
+#define     MT9M032_PLL_CONFIG1_OUTDIV_MASK	0x3f
+#define     MT9M032_PLL_CONFIG1_MUL_SHIFT	8
+#define MT9M032_READ_MODE1			0x1e
+#define MT9M032_READ_MODE2			0x20
+#define     MT9M032_READ_MODE2_VFLIP_SHIFT	15
+#define     MT9M032_READ_MODE2_HFLIP_SHIFT	14
+#define     MT9M032_READ_MODE2_ROW_BLC		0x40
+#define MT9M032_GAIN_GREEN1			0x2b
+#define MT9M032_GAIN_BLUE			0x2c
+#define MT9M032_GAIN_RED			0x2d
+#define MT9M032_GAIN_GREEN2			0x2e
+/* write only */
+#define MT9M032_GAIN_ALL			0x35
+#define     MT9M032_GAIN_DIGITAL_MASK		0x7f
+#define     MT9M032_GAIN_DIGITAL_SHIFT		8
+#define     MT9M032_GAIN_AMUL_SHIFT		6
+#define     MT9M032_GAIN_ANALOG_MASK		0x3f
+#define MT9M032_FORMATTER1			0x9e
+#define MT9M032_FORMATTER2			0x9f
+#define     MT9M032_FORMATTER2_DOUT_EN		0x1000
+#define     MT9M032_FORMATTER2_PIXCLK_EN	0x2000
+
+#define MT9M032_MAX_BLANKING_ROWS		0x7ff
+
+
+/*
+ * The availible MT9M032 datasheet is missing documentation for register 0x10
+ * MT9P031 seems to be close enough, so use constants from that datasheet for
+ * now.
+ * But keep the name MT9P031 to remind us, that this isn't really confirmed
+ * for this sensor.
+ */
+
+#define MT9P031_PLL_CONTROL			0x10
+#define     MT9P031_PLL_CONTROL_PWROFF		0x0050
+#define     MT9P031_PLL_CONTROL_PWRON		0x0051
+#define     MT9P031_PLL_CONTROL_USEPLL		0x0052
+
+
+
+/*
+ * width and height include active boundry and black parts
+ *
+ * column    0-  15 active boundry
+ * column   16-1455 image
+ * column 1456-1471 active boundry
+ * column 1472-1599 black
+ *
+ * row       0-  51 black
+ * row      53-  59 active boundry
+ * row      60-1139 image
+ * row    1140-1147 active boundry
+ * row    1148-1151 black
+ */
+#define MT9M032_WIDTH				1600
+#define MT9M032_HEIGHT				1152
+#define MT9M032_MINIMALSIZE			32
+
+#define to_mt9m032(sd)	container_of(sd, struct mt9m032, subdev)
+#define to_dev(sensor)	&((struct i2c_client *)v4l2_get_subdevdata(&sensor->subdev))->dev
+
+struct mt9m032 {
+	struct v4l2_subdev subdev;
+	struct media_pad pad;
+	struct mt9m032_platform_data *pdata;
+	struct v4l2_ctrl_handler ctrls;
+
+	bool streaming;
+
+	int pix_clock;
+
+	struct v4l2_mbus_framefmt format;	/* height and width always the same as in crop */
+	struct v4l2_rect crop;
+	struct v4l2_fract frame_interval;
+
+	struct v4l2_ctrl *hflip, *vflip;
+};
+
+
+static int mt9m032_read_reg(struct mt9m032 *sensor, u8 reg)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+
+	return i2c_smbus_read_word_swapped(client, reg);
+}
+
+static int mt9m032_write_reg(struct mt9m032 *sensor, u8 reg,
+		     const u16 data)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+
+	return i2c_smbus_write_word_swapped(client, reg, data);
+}
+
+
+static unsigned long mt9m032_row_time(struct mt9m032 *sensor, int width)
+{
+	int effective_width;
+	u64 ns;
+
+	effective_width = width + 716; /* emperical value */
+	ns = div_u64(((u64)1000000000) * effective_width, sensor->pix_clock);
+	dev_dbg(to_dev(sensor),	"MT9M032 line time: %llu ns\n", ns);
+	return ns;
+}
+
+static int mt9m032_update_timing(struct mt9m032 *sensor,
+				 struct v4l2_fract *interval,
+				 const struct v4l2_rect *crop)
+{
+	unsigned long row_time;
+	int additional_blanking_rows;
+	int min_blank;
+
+	if (!interval)
+		interval = &sensor->frame_interval;
+	if (!crop)
+		crop = &sensor->crop;
+
+	row_time = mt9m032_row_time(sensor, crop->width);
+
+	additional_blanking_rows = div_u64(((u64)1000000000) * interval->numerator, 
+	                                  ((u64)interval->denominator) * row_time)
+	                           - crop->height;
+
+	if (additional_blanking_rows > MT9M032_MAX_BLANKING_ROWS) {
+		/* hardware limits to 11 bit values */
+		interval->denominator = 1000;
+		interval->numerator = div_u64((crop->height + MT9M032_MAX_BLANKING_ROWS)
+		                              * ((u64)row_time) * interval->denominator,
+					      1000000000);
+		additional_blanking_rows = div_u64(((u64)1000000000) * interval->numerator, 
+	                                  ((u64)interval->denominator) * row_time)
+	                           - crop->height;
+	}
+	/* enforce minimal 1.6ms blanking time. */
+	min_blank = 1600000 / row_time;
+	additional_blanking_rows = clamp(additional_blanking_rows,
+	                                 min_blank, MT9M032_MAX_BLANKING_ROWS);
+
+	return mt9m032_write_reg(sensor, MT9M032_VBLANK, additional_blanking_rows);
+}
+
+static int mt9m032_update_geom_timing(struct mt9m032 *sensor,
+				 const struct v4l2_rect *crop)
+{
+	int ret;
+
+	ret = mt9m032_write_reg(sensor, MT9M032_COLUMN_SIZE, crop->width - 1);
+	if (!ret)
+		ret = mt9m032_write_reg(sensor, MT9M032_ROW_SIZE, crop->height - 1);
+	/* offsets compensate for black border */
+	if (!ret)
+		ret = mt9m032_write_reg(sensor, MT9M032_COLUMN_START, crop->left);
+	if (!ret)
+		ret = mt9m032_write_reg(sensor, MT9M032_ROW_START, crop->top);
+	if (!ret)
+		ret = mt9m032_update_timing(sensor, NULL, crop);
+	return ret;
+}
+
+static int update_formatter2(struct mt9m032 *sensor, bool streaming)
+{
+	u16 reg_val =   MT9M032_FORMATTER2_DOUT_EN
+		      | 0x0070;  /* parts reserved! */
+				 /* possibly for changing to 14-bit mode */
+
+	if (streaming)
+		reg_val |= MT9M032_FORMATTER2_PIXCLK_EN;   /* pixclock enable */
+
+	return mt9m032_write_reg(sensor, MT9M032_FORMATTER2, reg_val);
+}
+
+static int mt9m032_s_stream(struct v4l2_subdev *subdev, int streaming)
+{
+	struct mt9m032 *sensor = to_mt9m032(subdev);
+	int ret;
+
+	ret = update_formatter2(sensor, streaming);
+	if (!ret)
+		sensor->streaming = streaming;
+	return ret;
+}
+
+static int mt9m032_enum_mbus_code(struct v4l2_subdev *subdev,
+				  struct v4l2_subdev_fh *fh,
+				  struct v4l2_subdev_mbus_code_enum *code)
+{
+	if (code->index != 0 || code->pad != 0)
+		return -EINVAL;
+	code->code = V4L2_MBUS_FMT_Y8_1X8;
+	return 0;
+}
+
+static int mt9m032_enum_frame_size(struct v4l2_subdev *subdev,
+				   struct v4l2_subdev_fh *fh,
+				   struct v4l2_subdev_frame_size_enum *fse)
+{
+	if (fse->index != 0 || fse->code != V4L2_MBUS_FMT_Y8_1X8 || fse->pad != 0)
+		return -EINVAL;
+
+	fse->min_width = MT9M032_WIDTH;
+	fse->max_width = MT9M032_WIDTH;
+	fse->min_height = MT9M032_HEIGHT;
+	fse->max_height = MT9M032_HEIGHT;
+
+	return 0;
+}
+
+/**
+ * __mt9m032_get_pad_crop() - get crop rect
+ * @sensor:	pointer to the sensor struct
+ * @fh:	filehandle for getting the try crop rect from
+ * @which:	select try or active crop rect
+ * Returns a pointer the current active or fh relative try crop rect
+ */
+static struct v4l2_rect *__mt9m032_get_pad_crop(struct mt9m032 *sensor,
+						struct v4l2_subdev_fh *fh,
+						u32 which)
+{
+	switch (which) {
+	case V4L2_SUBDEV_FORMAT_TRY:
+		return v4l2_subdev_get_try_crop(fh, 0);
+	case V4L2_SUBDEV_FORMAT_ACTIVE:
+		return &sensor->crop;
+	default:
+		return NULL;
+	}
+}
+
+/**
+ * __mt9m032_get_pad_format() - get format
+ * @sensor:	pointer to the sensor struct
+ * @fh:	filehandle for getting the try format from
+ * @which:	select try or active format
+ * Returns a pointer the current active or fh relative try format
+ */
+static struct v4l2_mbus_framefmt *__mt9m032_get_pad_format(struct mt9m032 *sensor,
+							   struct v4l2_subdev_fh *fh,
+							   u32 which)
+{
+	switch (which) {
+	case V4L2_SUBDEV_FORMAT_TRY:
+		return v4l2_subdev_get_try_format(fh, 0);
+	case V4L2_SUBDEV_FORMAT_ACTIVE:
+		return &sensor->format;
+	default:
+		return NULL;
+	}
+}
+
+static int mt9m032_get_pad_format(struct v4l2_subdev *subdev,
+				  struct v4l2_subdev_fh *fh,
+				  struct v4l2_subdev_format *fmt)
+{
+	struct mt9m032 *sensor = to_mt9m032(subdev);
+	struct v4l2_mbus_framefmt *format;
+
+	format = __mt9m032_get_pad_format(sensor, fh, fmt->which);
+
+	fmt->format = *format;
+
+	return 0;
+}
+
+static int mt9m032_set_pad_format(struct v4l2_subdev *subdev,
+				  struct v4l2_subdev_fh *fh,
+				  struct v4l2_subdev_format *fmt)
+{
+	struct mt9m032 *sensor = to_mt9m032(subdev);
+
+	if (sensor->streaming)
+		return -EBUSY;
+		
+	
+	/*
+	 * fmt->format.colorspace, fmt->format.code and fmt->format.field are ignored
+	 * and thus forced to fixed values by the get call below.
+	 *
+	 * fmt->format.width, fmt->format.height are forced to the values set via crop
+	 */
+
+	return mt9m032_get_pad_format(subdev, fh, fmt);
+}
+
+static int mt9m032_get_crop(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh,
+			    struct v4l2_subdev_crop *crop)
+{
+	struct mt9m032 *sensor = to_mt9m032(subdev);
+	struct v4l2_rect *curcrop;
+
+	curcrop = __mt9m032_get_pad_crop(sensor, fh, crop->which);
+
+	crop->rect = *curcrop;
+
+	return 0;
+}
+
+static int mt9m032_set_crop(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh,
+		     struct v4l2_subdev_crop *crop)
+{
+	struct mt9m032 *sensor = to_mt9m032(subdev);
+	struct v4l2_mbus_framefmt tmp_format;
+	struct v4l2_rect tmp_crop_rect;
+	struct v4l2_mbus_framefmt *format;
+	struct v4l2_rect *crop_rect;
+	int ret = 0;
+
+	if (sensor->streaming)
+		return -EBUSY;
+
+	format = __mt9m032_get_pad_format(sensor, fh, crop->which);
+	crop_rect = __mt9m032_get_pad_crop(sensor, fh, crop->which);
+	if (crop->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
+		tmp_crop_rect = *crop_rect;
+		tmp_format = *format;
+		format = &tmp_format;
+		crop_rect = &tmp_crop_rect;
+	}
+
+	crop_rect->top = clamp(crop->rect.top, 0,
+			       MT9M032_HEIGHT - MT9M032_MINIMALSIZE) & ~1;
+	crop_rect->left = clamp(crop->rect.left, 0,
+			       MT9M032_WIDTH - MT9M032_MINIMALSIZE);
+	crop_rect->height = clamp(crop->rect.height, MT9M032_MINIMALSIZE,
+				  MT9M032_HEIGHT - crop_rect->top);
+	crop_rect->width = clamp(crop->rect.width, MT9M032_MINIMALSIZE,
+				 MT9M032_WIDTH - crop_rect->left) & ~1;
+
+	format->height = crop_rect->height;
+	format->width = crop_rect->width;
+
+	if (crop->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
+		ret = mt9m032_update_geom_timing(sensor, crop_rect);
+
+		if (!ret) {
+			sensor->crop = tmp_crop_rect;
+			sensor->format = tmp_format;
+		}
+		return ret;
+	}
+	
+	return ret;
+}
+
+static int mt9m032_get_frame_interval(struct v4l2_subdev *subdev,
+				      struct v4l2_subdev_frame_interval *fi)
+{
+	struct mt9m032 *sensor = to_mt9m032(subdev);
+
+	fi->pad = 0;
+	memset(fi->reserved, 0, sizeof(fi->reserved));
+	fi->interval = sensor->frame_interval;
+
+	return 0;
+}
+
+static int mt9m032_set_frame_interval(struct v4l2_subdev *subdev,
+				      struct v4l2_subdev_frame_interval *fi)
+{
+	struct mt9m032 *sensor = to_mt9m032(subdev);
+	int ret;
+
+	if (sensor->streaming)
+		return -EBUSY;
+
+	memset(fi->reserved, 0, sizeof(fi->reserved));
+
+	ret = mt9m032_update_timing(sensor, &fi->interval, NULL);
+	if (!ret)
+		sensor->frame_interval = fi->interval;
+	return ret;
+}
+
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+static int mt9m032_g_register(struct v4l2_subdev *sd,
+			      struct v4l2_dbg_register *reg)
+{
+	struct mt9m032 *sensor = to_mt9m032(sd);
+	struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+	int val;
+
+	if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
+		return -EINVAL;
+	if (reg->match.addr != client->addr)
+		return -ENODEV;
+
+	val = mt9m032_read_reg(sensor, reg->reg);
+	if (val < 0)
+		return -EIO;
+
+	reg->size = 2;
+	reg->val = val;
+
+	return 0;
+}
+
+static int mt9m032_s_register(struct v4l2_subdev *sd,
+			      struct v4l2_dbg_register *reg)
+{
+	struct mt9m032 *sensor = to_mt9m032(sd);
+	struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+	
+	if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
+		return -EINVAL;
+
+	if (reg->match.addr != client->addr)
+		return -ENODEV;
+
+	if (mt9m032_write_reg(sensor, reg->reg, reg->val) < 0)
+		return -EIO;
+
+	return 0;
+}
+#endif
+
+static int update_read_mode2(struct mt9m032 *sensor, bool vflip, bool hflip)
+{
+	int reg_val = (!!vflip) << MT9M032_READ_MODE2_VFLIP_SHIFT
+		      | (!!hflip) << MT9M032_READ_MODE2_HFLIP_SHIFT
+		      | MT9M032_READ_MODE2_ROW_BLC
+		      | 0x0007;
+
+	return mt9m032_write_reg(sensor, MT9M032_READ_MODE2, reg_val);
+}
+
+static int mt9m032_set_hflip(struct mt9m032 *sensor, s32 val)
+{
+	return update_read_mode2(sensor, sensor->vflip->cur.val, val);
+}
+
+static int mt9m032_set_vflip(struct mt9m032 *sensor, s32 val)
+{
+	return update_read_mode2(sensor, val, sensor->hflip->cur.val);
+}
+
+static int mt9m032_set_exposure(struct mt9m032 *sensor, s32 val)
+{
+	int shutter_width;
+	u16 high_val, low_val;
+	int ret;
+
+	/* shutter width is in row times */
+	shutter_width = (val * 1000) / mt9m032_row_time(sensor, sensor->crop.width);
+
+	high_val = (shutter_width >> 16) & 0xf;
+	low_val = shutter_width & 0xffff;
+
+	ret = mt9m032_write_reg(sensor, MT9M032_SHUTTER_WIDTH_HIGH, high_val);
+	if (!ret)
+		ret = mt9m032_write_reg(sensor, MT9M032_SHUTTER_WIDTH_LOW, low_val);
+
+	return ret;
+}
+
+static int mt9m032_set_gain(struct mt9m032 *sensor, s32 val)
+{
+	int digital_gain_val;	/* in 1/8th (0..127) */
+	int analog_mul;		/* 0 or 1 */
+	int analog_gain_val;	/* in 1/16th. (0..63) */
+	u16 reg_val;
+
+	digital_gain_val = 51; /* from setup example */
+
+	if (val < 63) {
+		analog_mul = 0;
+		analog_gain_val = val;
+	} else {
+		analog_mul = 1;
+		analog_gain_val = val / 2;
+	}
+
+	/* a_gain = (1+analog_mul) + (analog_gain_val+1)/16 */
+	/* overall_gain = a_gain * (1 + digital_gain_val / 8) */
+
+	reg_val = (digital_gain_val & MT9M032_GAIN_DIGITAL_MASK) << MT9M032_GAIN_DIGITAL_SHIFT
+		  | (analog_mul & 1) << MT9M032_GAIN_AMUL_SHIFT
+		  | (analog_gain_val & MT9M032_GAIN_ANALOG_MASK);
+
+	return mt9m032_write_reg(sensor, MT9M032_GAIN_ALL, reg_val);
+}
+
+static int mt9m032_setup_pll(struct mt9m032 *sensor)
+{
+	struct mt9m032_platform_data* pdata = sensor->pdata;
+	u16 reg_pll1;
+	unsigned int pre_div;
+	int res, ret;
+
+	/* TODO: also support other pre-div values */
+	if (pdata->pll_pre_div != 6) {
+		dev_warn(to_dev(sensor),
+			"Unsupported PLL pre-divisor value %u, using default 6\n",
+			pdata->pll_pre_div);
+	}
+	pre_div = 6;
+
+	sensor->pix_clock = pdata->ext_clock * pdata->pll_mul /
+		(pre_div * pdata->pll_out_div);
+
+	reg_pll1 = ((pdata->pll_out_div - 1) & MT9M032_PLL_CONFIG1_OUTDIV_MASK)
+		   | pdata->pll_mul << MT9M032_PLL_CONFIG1_MUL_SHIFT;
+
+	ret = mt9m032_write_reg(sensor, MT9M032_PLL_CONFIG1, reg_pll1);
+	if (!ret)
+		ret = mt9m032_write_reg(sensor,
+		                        MT9P031_PLL_CONTROL, 
+		                        MT9P031_PLL_CONTROL_PWRON | MT9P031_PLL_CONTROL_USEPLL);
+
+	if (!ret)
+		ret = mt9m032_write_reg(sensor, MT9M032_READ_MODE1, 0x8006);
+							/* more reserved, Continuous */
+							/* Master Mode */
+	if (!ret)
+		res = mt9m032_read_reg(sensor, MT9M032_READ_MODE1);
+
+	if (!ret)
+		ret = mt9m032_write_reg(sensor, MT9M032_FORMATTER1, 0x111e);
+					/* Set 14-bit mode, select 7 divider */
+
+	return ret;
+}
+
+static int mt9m032_try_ctrl(struct v4l2_ctrl *ctrl)
+{
+	if (ctrl->id == V4L2_CID_GAIN && ctrl->val >= 63) {
+		 /* round because of multiplier used for values >= 63 */
+		ctrl->val &= ~1;
+	}
+	
+	return 0;
+}
+
+static int mt9m032_set_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct mt9m032 *sensor = container_of(ctrl->handler, struct mt9m032, ctrls);
+
+	switch (ctrl->id) {
+	case V4L2_CID_GAIN:
+		return mt9m032_set_gain(sensor, ctrl->val);
+
+	case V4L2_CID_HFLIP:
+		return mt9m032_set_hflip(sensor, ctrl->val);
+
+	case V4L2_CID_VFLIP:
+		return mt9m032_set_vflip(sensor, ctrl->val);
+
+	case V4L2_CID_EXPOSURE:
+		return mt9m032_set_exposure(sensor, ctrl->val);
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct v4l2_subdev_video_ops mt9m032_video_ops = {
+	.s_stream = mt9m032_s_stream,
+	.g_frame_interval = mt9m032_get_frame_interval,
+	.s_frame_interval = mt9m032_set_frame_interval,
+};
+
+static struct v4l2_ctrl_ops mt9m032_ctrl_ops = {
+	.s_ctrl = mt9m032_set_ctrl,
+	.try_ctrl = mt9m032_try_ctrl,
+};
+
+
+static const struct v4l2_subdev_core_ops mt9m032_core_ops = {
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+	.g_register = mt9m032_g_register,
+	.s_register = mt9m032_s_register,
+#endif
+};
+
+static const struct v4l2_subdev_pad_ops mt9m032_pad_ops = {
+	.enum_mbus_code = mt9m032_enum_mbus_code,
+	.enum_frame_size = mt9m032_enum_frame_size,
+	.get_fmt = mt9m032_get_pad_format,
+	.set_fmt = mt9m032_set_pad_format,
+	.set_crop = mt9m032_set_crop,
+	.get_crop = mt9m032_get_crop,
+};
+
+static const struct v4l2_subdev_ops mt9m032_ops = {
+	.core = &mt9m032_core_ops,
+	.video = &mt9m032_video_ops,
+	.pad = &mt9m032_pad_ops,
+};
+
+static int mt9m032_probe(struct i2c_client *client,
+			 const struct i2c_device_id *devid)
+{
+	struct mt9m032 *sensor;
+	int chip_version;
+	int res, 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;
+	}
+
+	if (!client->dev.platform_data)
+		return -ENODEV;
+	
+	sensor = kzalloc(sizeof(*sensor), GFP_KERNEL);
+	if (sensor == NULL)
+		return -ENOMEM;
+	
+	sensor->pdata = client->dev.platform_data;
+	
+	v4l2_i2c_subdev_init(&sensor->subdev, client, &mt9m032_ops);
+	sensor->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+
+
+	/*
+	 * This driver was developed with a camera module with seperate external
+	 * pix clock. For setups which use the clock from the camera interface
+	 * the code will need to be extended with the appropriate platform
+	 * callback to setup the clock.
+	 */
+	chip_version = mt9m032_read_reg(sensor, MT9M032_CHIP_VERSION);
+	if (chip_version == MT9M032_CHIP_VERSION_VALUE) {
+		dev_info(&client->dev, "mt9m032: detected sensor.\n");
+	} else {
+		dev_warn(&client->dev, "mt9m032: error: detected unsupported chip version 0x%x\n",
+			 chip_version);
+		ret = -ENODEV;
+		goto free_sensor;
+	}
+
+	
+
+	sensor->frame_interval.numerator = 1;
+	sensor->frame_interval.denominator = 30;
+
+	sensor->crop.left = 416;
+	sensor->crop.top = 360;
+	sensor->crop.width = 640;
+	sensor->crop.height = 480;
+
+	sensor->format.width = sensor->crop.width;
+	sensor->format.height = sensor->crop.height;
+	sensor->format.code = V4L2_MBUS_FMT_Y8_1X8;
+	sensor->format.field = V4L2_FIELD_NONE;
+	sensor->format.colorspace = V4L2_COLORSPACE_SRGB;
+
+	v4l2_ctrl_handler_init(&sensor->ctrls, 4);
+	
+	v4l2_ctrl_new_std(&sensor->ctrls, &mt9m032_ctrl_ops,
+			  V4L2_CID_GAIN, 0, 127, 1, 64);
+
+	sensor->hflip = v4l2_ctrl_new_std(&sensor->ctrls, &mt9m032_ctrl_ops,
+			  V4L2_CID_HFLIP, 0, 1, 1, 0);
+	sensor->vflip = v4l2_ctrl_new_std(&sensor->ctrls, &mt9m032_ctrl_ops,
+			  V4L2_CID_VFLIP, 0, 1, 1, 0);
+	v4l2_ctrl_new_std(&sensor->ctrls, &mt9m032_ctrl_ops,
+			  V4L2_CID_EXPOSURE, 0, 8000, 1, 1700);    /* 1.7ms */
+
+
+	if (sensor->ctrls.error) {
+		ret = sensor->ctrls.error;
+		dev_err(&client->dev, "control initialization error %d\n", ret);
+		goto free_ctrl;
+	}
+
+	sensor->subdev.ctrl_handler = &sensor->ctrls;
+	sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
+	ret = media_entity_init(&sensor->subdev.entity, 1, &sensor->pad, 0);
+	if (ret < 0)
+		goto free_ctrl;
+	
+	ret = mt9m032_write_reg(sensor, MT9M032_RESET, 1);	/* reset on */
+	if (ret < 0)
+		goto free_ctrl;
+	mt9m032_write_reg(sensor, MT9M032_RESET, 0);	/* reset off */
+	if (ret < 0)
+		goto free_ctrl;
+
+	ret = mt9m032_setup_pll(sensor);
+	if (ret < 0)
+		goto free_ctrl;
+	msleep(10);
+
+	v4l2_ctrl_handler_setup(&sensor->ctrls);
+
+	/* SIZE */
+	ret = mt9m032_update_geom_timing(sensor, &sensor->crop);
+	if (ret < 0)
+		goto free_ctrl;
+
+	ret = mt9m032_write_reg(sensor, 0x41, 0x0000);	/* reserved !!! */
+	if (ret < 0)
+		goto free_ctrl;
+	ret = mt9m032_write_reg(sensor, 0x42, 0x0003);	/* reserved !!! */
+	if (ret < 0)
+		goto free_ctrl;
+	ret = mt9m032_write_reg(sensor, 0x43, 0x0003);	/* reserved !!! */
+	if (ret < 0)
+		goto free_ctrl;
+	ret = mt9m032_write_reg(sensor, 0x7f, 0x0000);	/* reserved !!! */
+	if (ret < 0)
+		goto free_ctrl;
+	if (sensor->pdata->invert_pixclock) {
+		mt9m032_write_reg(sensor, MT9M032_PIX_CLK_CTRL, MT9M032_PIX_CLK_CTRL_INV_PIXCLK);
+		if (ret < 0)
+			goto free_ctrl;
+	}
+
+	res = mt9m032_read_reg(sensor, MT9M032_PIX_CLK_CTRL);
+
+	ret = mt9m032_write_reg(sensor, MT9M032_RESTART, 1); /* Restart on */
+	if (ret < 0)
+		goto free_ctrl;
+	msleep(100);
+	ret = mt9m032_write_reg(sensor, MT9M032_RESTART, 0); /* Restart off */
+	if (ret < 0)
+		goto free_ctrl;
+	msleep(100);
+	ret = update_formatter2(sensor, false);
+	if (ret < 0)
+		goto free_ctrl;
+
+	return ret;
+
+free_ctrl:
+	v4l2_ctrl_handler_free(&sensor->ctrls);
+	
+free_sensor:
+	kfree(sensor);	
+	return ret;
+}
+
+static int mt9m032_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *subdev = i2c_get_clientdata(client);
+	struct mt9m032 *sensor = to_mt9m032(subdev);
+
+	v4l2_device_unregister_subdev(&sensor->subdev);
+	v4l2_ctrl_handler_free(&sensor->ctrls);
+	media_entity_cleanup(&sensor->subdev.entity);
+	kfree(sensor);
+	return 0;
+}
+
+static const struct i2c_device_id mt9m032_id_table[] = {
+	{MT9M032_NAME, 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, mt9m032_id_table);
+
+static struct i2c_driver mt9m032_i2c_driver = {
+	.driver = {
+		   .name = MT9M032_NAME,
+		   },
+	.probe = mt9m032_probe,
+	.remove = mt9m032_remove,
+	.id_table = mt9m032_id_table,
+};
+
+static int __init mt9m032_init(void)
+{
+	int rval;
+
+	rval = i2c_add_driver(&mt9m032_i2c_driver);
+	if (rval)
+		pr_err("%s: failed registering " MT9M032_NAME "\n", __func__);
+
+	return rval;
+}
+
+static void mt9m032_exit(void)
+{
+	i2c_del_driver(&mt9m032_i2c_driver);
+}
+
+module_init(mt9m032_init);
+module_exit(mt9m032_exit);
+
+MODULE_AUTHOR("Martin Hostettler");
+MODULE_DESCRIPTION("MT9M032 camera sensor driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/media/mt9m032.h b/include/media/mt9m032.h
new file mode 100644
index 0000000..94cefc5
--- /dev/null
+++ b/include/media/mt9m032.h
@@ -0,0 +1,38 @@
+/*
+ * Driver for MT9M032 CMOS Image Sensor from Micron
+ *
+ * Copyright (C) 2010-2011 Lund Engineering
+ * Contact: Gil Lund <gwlund@lundeng.com>
+ * Author: Martin Hostettler <martin@neutronstar.dyndns.org>
+ *
+ * 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
+ *
+ */
+
+#ifndef MT9M032_H
+#define MT9M032_H
+
+#define MT9M032_NAME		"mt9m032"
+#define MT9M032_I2C_ADDR	(0xb8 >> 1)
+
+struct mt9m032_platform_data {
+	u32 ext_clock;
+	u32 pll_pre_div;
+	u32 pll_mul;
+	u32 pll_out_div;
+	int invert_pixclock;
+
+};
+#endif /* MT9M032_H */
-- 
1.7.2.5