Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / media / i2c / mt9m032.c
diff --git a/kernel/drivers/media/i2c/mt9m032.c b/kernel/drivers/media/i2c/mt9m032.c
new file mode 100644 (file)
index 0000000..c7747bd
--- /dev/null
@@ -0,0 +1,901 @@
+/*
+ * 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/mutex.h>
+#include <linux/slab.h>
+#include <linux/v4l2-mediabus.h>
+
+#include <media/media-entity.h>
+#include <media/mt9m032.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-subdev.h>
+
+#include "aptina-pll.h"
+
+/*
+ * width and height include active boundary and black parts
+ *
+ * column    0-  15 active boundary
+ * column   16-1455 image
+ * column 1456-1471 active boundary
+ * column 1472-1599 black
+ *
+ * row       0-  51 black
+ * row      53-  59 active boundary
+ * row      60-1139 image
+ * row    1140-1147 active boundary
+ * row    1148-1151 black
+ */
+
+#define MT9M032_PIXEL_ARRAY_WIDTH                      1600
+#define MT9M032_PIXEL_ARRAY_HEIGHT                     1152
+
+#define MT9M032_CHIP_VERSION                           0x00
+#define                MT9M032_CHIP_VERSION_VALUE              0x1402
+#define MT9M032_ROW_START                              0x01
+#define                MT9M032_ROW_START_MIN                   0
+#define                MT9M032_ROW_START_MAX                   1152
+#define                MT9M032_ROW_START_DEF                   60
+#define MT9M032_COLUMN_START                           0x02
+#define                MT9M032_COLUMN_START_MIN                0
+#define                MT9M032_COLUMN_START_MAX                1600
+#define                MT9M032_COLUMN_START_DEF                16
+#define MT9M032_ROW_SIZE                               0x03
+#define                MT9M032_ROW_SIZE_MIN                    32
+#define                MT9M032_ROW_SIZE_MAX                    1152
+#define                MT9M032_ROW_SIZE_DEF                    1080
+#define MT9M032_COLUMN_SIZE                            0x04
+#define                MT9M032_COLUMN_SIZE_MIN                 32
+#define                MT9M032_COLUMN_SIZE_MAX                 1600
+#define                MT9M032_COLUMN_SIZE_DEF                 1440
+#define MT9M032_HBLANK                                 0x05
+#define MT9M032_VBLANK                                 0x06
+#define                MT9M032_VBLANK_MAX                      0x7ff
+#define MT9M032_SHUTTER_WIDTH_HIGH                     0x08
+#define MT9M032_SHUTTER_WIDTH_LOW                      0x09
+#define                MT9M032_SHUTTER_WIDTH_MIN               1
+#define                MT9M032_SHUTTER_WIDTH_MAX               1048575
+#define                MT9M032_SHUTTER_WIDTH_DEF               1943
+#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_PREDIV_MASK         0x3f
+#define                MT9M032_PLL_CONFIG1_MUL_SHIFT           8
+#define MT9M032_READ_MODE1                             0x1e
+#define                MT9M032_READ_MODE1_OUTPUT_BAD_FRAMES    (1 << 13)
+#define                MT9M032_READ_MODE1_MAINTAIN_FRAME_RATE  (1 << 12)
+#define                MT9M032_READ_MODE1_XOR_LINE_VALID       (1 << 11)
+#define                MT9M032_READ_MODE1_CONT_LINE_VALID      (1 << 10)
+#define                MT9M032_READ_MODE1_INVERT_TRIGGER       (1 << 9)
+#define                MT9M032_READ_MODE1_SNAPSHOT             (1 << 8)
+#define                MT9M032_READ_MODE1_GLOBAL_RESET         (1 << 7)
+#define                MT9M032_READ_MODE1_BULB_EXPOSURE        (1 << 6)
+#define                MT9M032_READ_MODE1_INVERT_STROBE        (1 << 5)
+#define                MT9M032_READ_MODE1_STROBE_ENABLE        (1 << 4)
+#define                MT9M032_READ_MODE1_STROBE_START_TRIG1   (0 << 2)
+#define                MT9M032_READ_MODE1_STROBE_START_EXP     (1 << 2)
+#define                MT9M032_READ_MODE1_STROBE_START_SHUTTER (2 << 2)
+#define                MT9M032_READ_MODE1_STROBE_START_TRIG2   (3 << 2)
+#define                MT9M032_READ_MODE1_STROBE_END_TRIG1     (0 << 0)
+#define                MT9M032_READ_MODE1_STROBE_END_EXP       (1 << 0)
+#define                MT9M032_READ_MODE1_STROBE_END_SHUTTER   (2 << 0)
+#define                MT9M032_READ_MODE1_STROBE_END_TRIG2     (3 << 0)
+#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_FORMATTER1_PLL_P1_6             (1 << 8)
+#define                MT9M032_FORMATTER1_PARALLEL             (1 << 12)
+#define MT9M032_FORMATTER2                             0x9f
+#define                MT9M032_FORMATTER2_DOUT_EN              0x1000
+#define                MT9M032_FORMATTER2_PIXCLK_EN            0x2000
+
+/*
+ * The available 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
+
+struct mt9m032 {
+       struct v4l2_subdev subdev;
+       struct media_pad pad;
+       struct mt9m032_platform_data *pdata;
+
+       unsigned int pix_clock;
+
+       struct v4l2_ctrl_handler ctrls;
+       struct {
+               struct v4l2_ctrl *hflip;
+               struct v4l2_ctrl *vflip;
+       };
+
+       struct mutex lock; /* Protects streaming, format, interval and crop */
+
+       bool streaming;
+
+       struct v4l2_mbus_framefmt format;
+       struct v4l2_rect crop;
+       struct v4l2_fract frame_interval;
+};
+
+#define to_mt9m032(sd) container_of(sd, struct mt9m032, subdev)
+#define to_dev(sensor) \
+       (&((struct i2c_client *)v4l2_get_subdevdata(&(sensor)->subdev))->dev)
+
+static int mt9m032_read(struct i2c_client *client, u8 reg)
+{
+       return i2c_smbus_read_word_swapped(client, reg);
+}
+
+static int mt9m032_write(struct i2c_client *client, u8 reg, const u16 data)
+{
+       return i2c_smbus_write_word_swapped(client, reg, data);
+}
+
+static u32 mt9m032_row_time(struct mt9m032 *sensor, unsigned int width)
+{
+       unsigned int effective_width;
+       u32 ns;
+
+       effective_width = width + 716; /* empirical value */
+       ns = div_u64(1000000000ULL * effective_width, sensor->pix_clock);
+       dev_dbg(to_dev(sensor), "MT9M032 line time: %u ns\n", ns);
+       return ns;
+}
+
+static int mt9m032_update_timing(struct mt9m032 *sensor,
+                                struct v4l2_fract *interval)
+{
+       struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+       struct v4l2_rect *crop = &sensor->crop;
+       unsigned int min_vblank;
+       unsigned int vblank;
+       u32 row_time;
+
+       if (!interval)
+               interval = &sensor->frame_interval;
+
+       row_time = mt9m032_row_time(sensor, crop->width);
+
+       vblank = div_u64(1000000000ULL * interval->numerator,
+                        (u64)row_time * interval->denominator)
+              - crop->height;
+
+       if (vblank > MT9M032_VBLANK_MAX) {
+               /* hardware limits to 11 bit values */
+               interval->denominator = 1000;
+               interval->numerator =
+                       div_u64((crop->height + MT9M032_VBLANK_MAX) *
+                               (u64)row_time * interval->denominator,
+                               1000000000ULL);
+               vblank = div_u64(1000000000ULL * interval->numerator,
+                                (u64)row_time * interval->denominator)
+                      - crop->height;
+       }
+       /* enforce minimal 1.6ms blanking time. */
+       min_vblank = 1600000 / row_time;
+       vblank = clamp_t(unsigned int, vblank, min_vblank, MT9M032_VBLANK_MAX);
+
+       return mt9m032_write(client, MT9M032_VBLANK, vblank);
+}
+
+static int mt9m032_update_geom_timing(struct mt9m032 *sensor)
+{
+       struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+       int ret;
+
+       ret = mt9m032_write(client, MT9M032_COLUMN_SIZE,
+                           sensor->crop.width - 1);
+       if (!ret)
+               ret = mt9m032_write(client, MT9M032_ROW_SIZE,
+                                   sensor->crop.height - 1);
+       if (!ret)
+               ret = mt9m032_write(client, MT9M032_COLUMN_START,
+                                   sensor->crop.left);
+       if (!ret)
+               ret = mt9m032_write(client, MT9M032_ROW_START,
+                                   sensor->crop.top);
+       if (!ret)
+               ret = mt9m032_update_timing(sensor, NULL);
+       return ret;
+}
+
+static int update_formatter2(struct mt9m032 *sensor, bool streaming)
+{
+       struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+       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(client, MT9M032_FORMATTER2, reg_val);
+}
+
+static int mt9m032_setup_pll(struct mt9m032 *sensor)
+{
+       static const struct aptina_pll_limits limits = {
+               .ext_clock_min = 8000000,
+               .ext_clock_max = 16500000,
+               .int_clock_min = 2000000,
+               .int_clock_max = 24000000,
+               .out_clock_min = 322000000,
+               .out_clock_max = 693000000,
+               .pix_clock_max = 99000000,
+               .n_min = 1,
+               .n_max = 64,
+               .m_min = 16,
+               .m_max = 255,
+               .p1_min = 6,
+               .p1_max = 7,
+       };
+
+       struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+       struct mt9m032_platform_data *pdata = sensor->pdata;
+       struct aptina_pll pll;
+       u16 reg_val;
+       int ret;
+
+       pll.ext_clock = pdata->ext_clock;
+       pll.pix_clock = pdata->pix_clock;
+
+       ret = aptina_pll_calculate(&client->dev, &limits, &pll);
+       if (ret < 0)
+               return ret;
+
+       sensor->pix_clock = pdata->pix_clock;
+
+       ret = mt9m032_write(client, MT9M032_PLL_CONFIG1,
+                           (pll.m << MT9M032_PLL_CONFIG1_MUL_SHIFT) |
+                           ((pll.n - 1) & MT9M032_PLL_CONFIG1_PREDIV_MASK));
+       if (!ret)
+               ret = mt9m032_write(client, MT9P031_PLL_CONTROL,
+                                   MT9P031_PLL_CONTROL_PWRON |
+                                   MT9P031_PLL_CONTROL_USEPLL);
+       if (!ret)               /* more reserved, Continuous, Master Mode */
+               ret = mt9m032_write(client, MT9M032_READ_MODE1, 0x8000 |
+                                   MT9M032_READ_MODE1_STROBE_START_EXP |
+                                   MT9M032_READ_MODE1_STROBE_END_SHUTTER);
+       if (!ret) {
+               reg_val = (pll.p1 == 6 ? MT9M032_FORMATTER1_PLL_P1_6 : 0)
+                       | MT9M032_FORMATTER1_PARALLEL | 0x001e; /* 14-bit */
+               ret = mt9m032_write(client, MT9M032_FORMATTER1, reg_val);
+       }
+
+       return ret;
+}
+
+/* -----------------------------------------------------------------------------
+ * Subdev pad operations
+ */
+
+static int mt9m032_enum_mbus_code(struct v4l2_subdev *subdev,
+                                 struct v4l2_subdev_pad_config *cfg,
+                                 struct v4l2_subdev_mbus_code_enum *code)
+{
+       if (code->index != 0)
+               return -EINVAL;
+
+       code->code = MEDIA_BUS_FMT_Y8_1X8;
+       return 0;
+}
+
+static int mt9m032_enum_frame_size(struct v4l2_subdev *subdev,
+                                  struct v4l2_subdev_pad_config *cfg,
+                                  struct v4l2_subdev_frame_size_enum *fse)
+{
+       if (fse->index != 0 || fse->code != MEDIA_BUS_FMT_Y8_1X8)
+               return -EINVAL;
+
+       fse->min_width = MT9M032_COLUMN_SIZE_DEF;
+       fse->max_width = MT9M032_COLUMN_SIZE_DEF;
+       fse->min_height = MT9M032_ROW_SIZE_DEF;
+       fse->max_height = MT9M032_ROW_SIZE_DEF;
+
+       return 0;
+}
+
+/**
+ * __mt9m032_get_pad_crop() - get crop rect
+ * @sensor: pointer to the sensor struct
+ * @cfg: v4l2_subdev_pad_config 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_pad_config *cfg,
+                      enum v4l2_subdev_format_whence which)
+{
+       switch (which) {
+       case V4L2_SUBDEV_FORMAT_TRY:
+               return v4l2_subdev_get_try_crop(&sensor->subdev, cfg, 0);
+       case V4L2_SUBDEV_FORMAT_ACTIVE:
+               return &sensor->crop;
+       default:
+               return NULL;
+       }
+}
+
+/**
+ * __mt9m032_get_pad_format() - get format
+ * @sensor: pointer to the sensor struct
+ * @cfg: v4l2_subdev_pad_config 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_pad_config *cfg,
+                        enum v4l2_subdev_format_whence which)
+{
+       switch (which) {
+       case V4L2_SUBDEV_FORMAT_TRY:
+               return v4l2_subdev_get_try_format(&sensor->subdev, cfg, 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_pad_config *cfg,
+                                 struct v4l2_subdev_format *fmt)
+{
+       struct mt9m032 *sensor = to_mt9m032(subdev);
+
+       mutex_lock(&sensor->lock);
+       fmt->format = *__mt9m032_get_pad_format(sensor, cfg, fmt->which);
+       mutex_unlock(&sensor->lock);
+
+       return 0;
+}
+
+static int mt9m032_set_pad_format(struct v4l2_subdev *subdev,
+                                 struct v4l2_subdev_pad_config *cfg,
+                                 struct v4l2_subdev_format *fmt)
+{
+       struct mt9m032 *sensor = to_mt9m032(subdev);
+       int ret;
+
+       mutex_lock(&sensor->lock);
+
+       if (sensor->streaming && fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
+               ret = -EBUSY;
+               goto done;
+       }
+
+       /* Scaling is not supported, the format is thus fixed. */
+       fmt->format = *__mt9m032_get_pad_format(sensor, cfg, fmt->which);
+       ret = 0;
+
+done:
+       mutex_unlock(&sensor->lock);
+       return ret;
+}
+
+static int mt9m032_get_pad_selection(struct v4l2_subdev *subdev,
+                                    struct v4l2_subdev_pad_config *cfg,
+                                    struct v4l2_subdev_selection *sel)
+{
+       struct mt9m032 *sensor = to_mt9m032(subdev);
+
+       if (sel->target != V4L2_SEL_TGT_CROP)
+               return -EINVAL;
+
+       mutex_lock(&sensor->lock);
+       sel->r = *__mt9m032_get_pad_crop(sensor, cfg, sel->which);
+       mutex_unlock(&sensor->lock);
+
+       return 0;
+}
+
+static int mt9m032_set_pad_selection(struct v4l2_subdev *subdev,
+                                    struct v4l2_subdev_pad_config *cfg,
+                                    struct v4l2_subdev_selection *sel)
+{
+       struct mt9m032 *sensor = to_mt9m032(subdev);
+       struct v4l2_mbus_framefmt *format;
+       struct v4l2_rect *__crop;
+       struct v4l2_rect rect;
+       int ret = 0;
+
+       if (sel->target != V4L2_SEL_TGT_CROP)
+               return -EINVAL;
+
+       mutex_lock(&sensor->lock);
+
+       if (sensor->streaming && sel->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
+               ret = -EBUSY;
+               goto done;
+       }
+
+       /* Clamp the crop rectangle boundaries and align them to a multiple of 2
+        * pixels to ensure a GRBG Bayer pattern.
+        */
+       rect.left = clamp(ALIGN(sel->r.left, 2), MT9M032_COLUMN_START_MIN,
+                         MT9M032_COLUMN_START_MAX);
+       rect.top = clamp(ALIGN(sel->r.top, 2), MT9M032_ROW_START_MIN,
+                        MT9M032_ROW_START_MAX);
+       rect.width = clamp_t(unsigned int, ALIGN(sel->r.width, 2),
+                            MT9M032_COLUMN_SIZE_MIN, MT9M032_COLUMN_SIZE_MAX);
+       rect.height = clamp_t(unsigned int, ALIGN(sel->r.height, 2),
+                             MT9M032_ROW_SIZE_MIN, MT9M032_ROW_SIZE_MAX);
+
+       rect.width = min_t(unsigned int, rect.width,
+                          MT9M032_PIXEL_ARRAY_WIDTH - rect.left);
+       rect.height = min_t(unsigned int, rect.height,
+                           MT9M032_PIXEL_ARRAY_HEIGHT - rect.top);
+
+       __crop = __mt9m032_get_pad_crop(sensor, cfg, sel->which);
+
+       if (rect.width != __crop->width || rect.height != __crop->height) {
+               /* Reset the output image size if the crop rectangle size has
+                * been modified.
+                */
+               format = __mt9m032_get_pad_format(sensor, cfg, sel->which);
+               format->width = rect.width;
+               format->height = rect.height;
+       }
+
+       *__crop = rect;
+       sel->r = rect;
+
+       if (sel->which == V4L2_SUBDEV_FORMAT_ACTIVE)
+               ret = mt9m032_update_geom_timing(sensor);
+
+done:
+       mutex_unlock(&sensor->lock);
+       return ret;
+}
+
+static int mt9m032_get_frame_interval(struct v4l2_subdev *subdev,
+                                     struct v4l2_subdev_frame_interval *fi)
+{
+       struct mt9m032 *sensor = to_mt9m032(subdev);
+
+       mutex_lock(&sensor->lock);
+       memset(fi, 0, sizeof(*fi));
+       fi->interval = sensor->frame_interval;
+       mutex_unlock(&sensor->lock);
+
+       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;
+
+       mutex_lock(&sensor->lock);
+
+       if (sensor->streaming) {
+               ret = -EBUSY;
+               goto done;
+       }
+
+       /* Avoid divisions by 0. */
+       if (fi->interval.denominator == 0)
+               fi->interval.denominator = 1;
+
+       ret = mt9m032_update_timing(sensor, &fi->interval);
+       if (!ret)
+               sensor->frame_interval = fi->interval;
+
+done:
+       mutex_unlock(&sensor->lock);
+       return ret;
+}
+
+static int mt9m032_s_stream(struct v4l2_subdev *subdev, int streaming)
+{
+       struct mt9m032 *sensor = to_mt9m032(subdev);
+       int ret;
+
+       mutex_lock(&sensor->lock);
+       ret = update_formatter2(sensor, streaming);
+       if (!ret)
+               sensor->streaming = streaming;
+       mutex_unlock(&sensor->lock);
+
+       return ret;
+}
+
+/* -----------------------------------------------------------------------------
+ * V4L2 subdev core operations
+ */
+
+#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->reg > 0xff)
+               return -EINVAL;
+
+       val = mt9m032_read(client, reg->reg);
+       if (val < 0)
+               return -EIO;
+
+       reg->size = 2;
+       reg->val = val;
+
+       return 0;
+}
+
+static int mt9m032_s_register(struct v4l2_subdev *sd,
+                             const struct v4l2_dbg_register *reg)
+{
+       struct mt9m032 *sensor = to_mt9m032(sd);
+       struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+
+       if (reg->reg > 0xff)
+               return -EINVAL;
+
+       return mt9m032_write(client, reg->reg, reg->val);
+}
+#endif
+
+/* -----------------------------------------------------------------------------
+ * V4L2 subdev control operations
+ */
+
+static int update_read_mode2(struct mt9m032 *sensor, bool vflip, bool hflip)
+{
+       struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+       int reg_val = (vflip << MT9M032_READ_MODE2_VFLIP_SHIFT)
+                   | (hflip << MT9M032_READ_MODE2_HFLIP_SHIFT)
+                   | MT9M032_READ_MODE2_ROW_BLC
+                   | 0x0007;
+
+       return mt9m032_write(client, MT9M032_READ_MODE2, reg_val);
+}
+
+static int mt9m032_set_gain(struct mt9m032 *sensor, s32 val)
+{
+       struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+       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(client, MT9M032_GAIN_ALL, reg_val);
+}
+
+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);
+       struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
+       int ret;
+
+       switch (ctrl->id) {
+       case V4L2_CID_GAIN:
+               return mt9m032_set_gain(sensor, ctrl->val);
+
+       case V4L2_CID_HFLIP:
+       /* case V4L2_CID_VFLIP: -- In the same cluster */
+               return update_read_mode2(sensor, sensor->vflip->val,
+                                        sensor->hflip->val);
+
+       case V4L2_CID_EXPOSURE:
+               ret = mt9m032_write(client, MT9M032_SHUTTER_WIDTH_HIGH,
+                                   (ctrl->val >> 16) & 0xffff);
+               if (ret < 0)
+                       return ret;
+
+               return mt9m032_write(client, MT9M032_SHUTTER_WIDTH_LOW,
+                                    ctrl->val & 0xffff);
+       }
+
+       return 0;
+}
+
+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_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 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_selection = mt9m032_set_pad_selection,
+       .get_selection = mt9m032_get_pad_selection,
+};
+
+static const struct v4l2_subdev_ops mt9m032_ops = {
+       .core = &mt9m032_core_ops,
+       .video = &mt9m032_video_ops,
+       .pad = &mt9m032_pad_ops,
+};
+
+/* -----------------------------------------------------------------------------
+ * Driver initialization and probing
+ */
+
+static int mt9m032_probe(struct i2c_client *client,
+                        const struct i2c_device_id *devid)
+{
+       struct mt9m032_platform_data *pdata = client->dev.platform_data;
+       struct i2c_adapter *adapter = client->adapter;
+       struct mt9m032 *sensor;
+       int chip_version;
+       int ret;
+
+       if (pdata == NULL) {
+               dev_err(&client->dev, "No platform data\n");
+               return -EINVAL;
+       }
+
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) {
+               dev_warn(&client->dev,
+                        "I2C-Adapter doesn't support I2C_FUNC_SMBUS_WORD\n");
+               return -EIO;
+       }
+
+       if (!client->dev.platform_data)
+               return -ENODEV;
+
+       sensor = devm_kzalloc(&client->dev, sizeof(*sensor), GFP_KERNEL);
+       if (sensor == NULL)
+               return -ENOMEM;
+
+       mutex_init(&sensor->lock);
+
+       sensor->pdata = pdata;
+
+       v4l2_i2c_subdev_init(&sensor->subdev, client, &mt9m032_ops);
+       sensor->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+
+       chip_version = mt9m032_read(client, MT9M032_CHIP_VERSION);
+       if (chip_version != MT9M032_CHIP_VERSION_VALUE) {
+               dev_err(&client->dev, "MT9M032 not detected, wrong version "
+                       "0x%04x\n", chip_version);
+               ret = -ENODEV;
+               goto error_sensor;
+       }
+
+       dev_info(&client->dev, "MT9M032 detected at address 0x%02x\n",
+                client->addr);
+
+       sensor->frame_interval.numerator = 1;
+       sensor->frame_interval.denominator = 30;
+
+       sensor->crop.left = MT9M032_COLUMN_START_DEF;
+       sensor->crop.top = MT9M032_ROW_START_DEF;
+       sensor->crop.width = MT9M032_COLUMN_SIZE_DEF;
+       sensor->crop.height = MT9M032_ROW_SIZE_DEF;
+
+       sensor->format.width = sensor->crop.width;
+       sensor->format.height = sensor->crop.height;
+       sensor->format.code = MEDIA_BUS_FMT_Y8_1X8;
+       sensor->format.field = V4L2_FIELD_NONE;
+       sensor->format.colorspace = V4L2_COLORSPACE_SRGB;
+
+       v4l2_ctrl_handler_init(&sensor->ctrls, 5);
+
+       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, MT9M032_SHUTTER_WIDTH_MIN,
+                         MT9M032_SHUTTER_WIDTH_MAX, 1,
+                         MT9M032_SHUTTER_WIDTH_DEF);
+       v4l2_ctrl_new_std(&sensor->ctrls, &mt9m032_ctrl_ops,
+                         V4L2_CID_PIXEL_RATE, pdata->pix_clock,
+                         pdata->pix_clock, 1, pdata->pix_clock);
+
+       if (sensor->ctrls.error) {
+               ret = sensor->ctrls.error;
+               dev_err(&client->dev, "control initialization error %d\n", ret);
+               goto error_ctrl;
+       }
+
+       v4l2_ctrl_cluster(2, &sensor->hflip);
+
+       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 error_ctrl;
+
+       ret = mt9m032_write(client, MT9M032_RESET, 1);  /* reset on */
+       if (ret < 0)
+               goto error_entity;
+       ret = mt9m032_write(client, MT9M032_RESET, 0);  /* reset off */
+       if (ret < 0)
+               goto error_entity;
+
+       ret = mt9m032_setup_pll(sensor);
+       if (ret < 0)
+               goto error_entity;
+       usleep_range(10000, 11000);
+
+       ret = v4l2_ctrl_handler_setup(&sensor->ctrls);
+       if (ret < 0)
+               goto error_entity;
+
+       /* SIZE */
+       ret = mt9m032_update_geom_timing(sensor);
+       if (ret < 0)
+               goto error_entity;
+
+       ret = mt9m032_write(client, 0x41, 0x0000);      /* reserved !!! */
+       if (ret < 0)
+               goto error_entity;
+       ret = mt9m032_write(client, 0x42, 0x0003);      /* reserved !!! */
+       if (ret < 0)
+               goto error_entity;
+       ret = mt9m032_write(client, 0x43, 0x0003);      /* reserved !!! */
+       if (ret < 0)
+               goto error_entity;
+       ret = mt9m032_write(client, 0x7f, 0x0000);      /* reserved !!! */
+       if (ret < 0)
+               goto error_entity;
+       if (sensor->pdata->invert_pixclock) {
+               ret = mt9m032_write(client, MT9M032_PIX_CLK_CTRL,
+                                   MT9M032_PIX_CLK_CTRL_INV_PIXCLK);
+               if (ret < 0)
+                       goto error_entity;
+       }
+
+       ret = mt9m032_write(client, MT9M032_RESTART, 1); /* Restart on */
+       if (ret < 0)
+               goto error_entity;
+       msleep(100);
+       ret = mt9m032_write(client, MT9M032_RESTART, 0); /* Restart off */
+       if (ret < 0)
+               goto error_entity;
+       msleep(100);
+       ret = update_formatter2(sensor, false);
+       if (ret < 0)
+               goto error_entity;
+
+       return ret;
+
+error_entity:
+       media_entity_cleanup(&sensor->subdev.entity);
+error_ctrl:
+       v4l2_ctrl_handler_free(&sensor->ctrls);
+error_sensor:
+       mutex_destroy(&sensor->lock);
+       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(subdev);
+       v4l2_ctrl_handler_free(&sensor->ctrls);
+       media_entity_cleanup(&subdev->entity);
+       mutex_destroy(&sensor->lock);
+       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,
+};
+
+module_i2c_driver(mt9m032_i2c_driver);
+
+MODULE_AUTHOR("Martin Hostettler <martin@neutronstar.dyndns.org>");
+MODULE_DESCRIPTION("MT9M032 camera sensor driver");
+MODULE_LICENSE("GPL v2");