media: ov2685: add support for OV2685 sensor

This patch adds driver for Omnivision's ov2685 sensor.
Though the ov2685 can output yuv data, this driver only
supports the raw bayer format, including the following features:
  - output 1600x1200 at 30fps
  - test patterns
  - manual exposure/gain control
  - vblank and hblank
  - media controller
  - runtime pm

[Sakari Ailus: trivial: ov5695_of_match -> ov2685_of_match]

Signed-off-by: Shunqian Zheng <zhengsq@rock-chips.com>
Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

3 files changed, 858 insertions, 0 deletions

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 00377fe06504..26549f765536 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -595,6 +595,18 @@ config VIDEO_OV2659
 	  To compile this driver as a module, choose M here: the
 	  module will be called ov2659.
 
+config VIDEO_OV2685
+	tristate "OmniVision OV2685 sensor support"
+	depends on VIDEO_V4L2 && I2C && MEDIA_CONTROLLER
+	depends on MEDIA_CAMERA_SUPPORT
+	select V4L2_FWNODE
+	---help---
+	  This is a Video4Linux2 sensor-level driver for the OmniVision
+	  OV2685 camera.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ov2685.
+
 config VIDEO_OV5640
 	tristate "OmniVision OV5640 sensor support"
 	depends on OF
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index 0cef61e4bdcb..e4f420d730e8 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_VIDEO_SONY_BTF_MPX) += sony-btf-mpx.o
 obj-$(CONFIG_VIDEO_UPD64031A) += upd64031a.o
 obj-$(CONFIG_VIDEO_UPD64083) += upd64083.o
 obj-$(CONFIG_VIDEO_OV2640) += ov2640.o
+obj-$(CONFIG_VIDEO_OV2685) += ov2685.o
 obj-$(CONFIG_VIDEO_OV5640) += ov5640.o
 obj-$(CONFIG_VIDEO_OV5645) += ov5645.o
 obj-$(CONFIG_VIDEO_OV5647) += ov5647.o
diff --git a/drivers/media/i2c/ov2685.c b/drivers/media/i2c/ov2685.c
new file mode 100644
index 000000000000..df4abecd8d74
--- /dev/null
+++ b/drivers/media/i2c/ov2685.c
@@ -0,0 +1,845 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ov2685 driver
+ *
+ * Copyright (C) 2017 Fuzhou Rockchip Electronics Co., Ltd.
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
+#include <linux/sysfs.h>
+#include <media/media-entity.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-subdev.h>
+
+#define CHIP_ID				0x2685
+#define OV2685_REG_CHIP_ID		0x300a
+
+#define OV2685_XVCLK_FREQ		24000000
+
+#define REG_SC_CTRL_MODE		0x0100
+#define     SC_CTRL_MODE_STANDBY	0x0
+#define     SC_CTRL_MODE_STREAMING	BIT(0)
+
+#define OV2685_REG_EXPOSURE		0x3500
+#define	OV2685_EXPOSURE_MIN		4
+#define	OV2685_EXPOSURE_STEP		1
+
+#define OV2685_REG_VTS			0x380e
+#define OV2685_VTS_MAX			0x7fff
+
+#define OV2685_REG_GAIN			0x350a
+#define OV2685_GAIN_MIN			0
+#define OV2685_GAIN_MAX			0x07ff
+#define OV2685_GAIN_STEP		0x1
+#define OV2685_GAIN_DEFAULT		0x0036
+
+#define OV2685_REG_TEST_PATTERN		0x5080
+#define OV2685_TEST_PATTERN_DISABLED		0x00
+#define OV2685_TEST_PATTERN_COLOR_BAR		0x80
+#define OV2685_TEST_PATTERN_RANDOM		0x81
+#define OV2685_TEST_PATTERN_COLOR_BAR_FADE	0x88
+#define OV2685_TEST_PATTERN_BW_SQUARE		0x92
+#define OV2685_TEST_PATTERN_COLOR_SQUARE	0x82
+
+#define REG_NULL			0xFFFF
+
+#define OV2685_REG_VALUE_08BIT		1
+#define OV2685_REG_VALUE_16BIT		2
+#define OV2685_REG_VALUE_24BIT		3
+
+#define OV2685_LANES			1
+#define OV2685_BITS_PER_SAMPLE		10
+
+static const char * const ov2685_supply_names[] = {
+	"avdd",		/* Analog power */
+	"dovdd",	/* Digital I/O power */
+	"dvdd",		/* Digital core power */
+};
+
+#define OV2685_NUM_SUPPLIES ARRAY_SIZE(ov2685_supply_names)
+
+struct regval {
+	u16 addr;
+	u8 val;
+};
+
+struct ov2685_mode {
+	u32 width;
+	u32 height;
+	u32 exp_def;
+	u32 hts_def;
+	u32 vts_def;
+	const struct regval *reg_list;
+};
+
+struct ov2685 {
+	struct i2c_client	*client;
+	struct clk		*xvclk;
+	struct gpio_desc	*reset_gpio;
+	struct regulator_bulk_data supplies[OV2685_NUM_SUPPLIES];
+
+	bool			streaming;
+	struct mutex		mutex;
+	struct v4l2_subdev	subdev;
+	struct media_pad	pad;
+	struct v4l2_ctrl	*anal_gain;
+	struct v4l2_ctrl	*exposure;
+	struct v4l2_ctrl	*hblank;
+	struct v4l2_ctrl	*vblank;
+	struct v4l2_ctrl	*test_pattern;
+	struct v4l2_ctrl_handler ctrl_handler;
+
+	const struct ov2685_mode *cur_mode;
+};
+
+#define to_ov2685(sd) container_of(sd, struct ov2685, subdev)
+
+/* PLL settings bases on 24M xvclk */
+static struct regval ov2685_1600x1200_regs[] = {
+	{0x0103, 0x01},
+	{0x0100, 0x00},
+	{0x3002, 0x00},
+	{0x3016, 0x1c},
+	{0x3018, 0x44},
+	{0x301d, 0xf0},
+	{0x3020, 0x00},
+	{0x3082, 0x37},
+	{0x3083, 0x03},
+	{0x3084, 0x09},
+	{0x3085, 0x04},
+	{0x3086, 0x00},
+	{0x3087, 0x00},
+	{0x3501, 0x4e},
+	{0x3502, 0xe0},
+	{0x3503, 0x07},
+	{0x350b, 0x36},
+	{0x3600, 0xb4},
+	{0x3603, 0x35},
+	{0x3604, 0x24},
+	{0x3605, 0x00},
+	{0x3620, 0x24},
+	{0x3621, 0x34},
+	{0x3622, 0x03},
+	{0x3628, 0x10},
+	{0x3705, 0x3c},
+	{0x370a, 0x21},
+	{0x370c, 0x50},
+	{0x370d, 0xc0},
+	{0x3717, 0x58},
+	{0x3718, 0x80},
+	{0x3720, 0x00},
+	{0x3721, 0x09},
+	{0x3722, 0x06},
+	{0x3723, 0x59},
+	{0x3738, 0x99},
+	{0x3781, 0x80},
+	{0x3784, 0x0c},
+	{0x3789, 0x60},
+	{0x3800, 0x00},
+	{0x3801, 0x00},
+	{0x3802, 0x00},
+	{0x3803, 0x00},
+	{0x3804, 0x06},
+	{0x3805, 0x4f},
+	{0x3806, 0x04},
+	{0x3807, 0xbf},
+	{0x3808, 0x06},
+	{0x3809, 0x40},
+	{0x380a, 0x04},
+	{0x380b, 0xb0},
+	{0x380c, 0x06},
+	{0x380d, 0xa4},
+	{0x380e, 0x05},
+	{0x380f, 0x0e},
+	{0x3810, 0x00},
+	{0x3811, 0x08},
+	{0x3812, 0x00},
+	{0x3813, 0x08},
+	{0x3814, 0x11},
+	{0x3815, 0x11},
+	{0x3819, 0x04},
+	{0x3820, 0xc0},
+	{0x3821, 0x00},
+	{0x3a06, 0x01},
+	{0x3a07, 0x84},
+	{0x3a08, 0x01},
+	{0x3a09, 0x43},
+	{0x3a0a, 0x24},
+	{0x3a0b, 0x60},
+	{0x3a0c, 0x28},
+	{0x3a0d, 0x60},
+	{0x3a0e, 0x04},
+	{0x3a0f, 0x8c},
+	{0x3a10, 0x05},
+	{0x3a11, 0x0c},
+	{0x4000, 0x81},
+	{0x4001, 0x40},
+	{0x4008, 0x02},
+	{0x4009, 0x09},
+	{0x4300, 0x00},
+	{0x430e, 0x00},
+	{0x4602, 0x02},
+	{0x481b, 0x40},
+	{0x481f, 0x40},
+	{0x4837, 0x18},
+	{0x5000, 0x1f},
+	{0x5001, 0x05},
+	{0x5002, 0x30},
+	{0x5003, 0x04},
+	{0x5004, 0x00},
+	{0x5005, 0x0c},
+	{0x5280, 0x15},
+	{0x5281, 0x06},
+	{0x5282, 0x06},
+	{0x5283, 0x08},
+	{0x5284, 0x1c},
+	{0x5285, 0x1c},
+	{0x5286, 0x20},
+	{0x5287, 0x10},
+	{REG_NULL, 0x00}
+};
+
+#define OV2685_LINK_FREQ_330MHZ		330000000
+static const s64 link_freq_menu_items[] = {
+	OV2685_LINK_FREQ_330MHZ
+};
+
+static const char * const ov2685_test_pattern_menu[] = {
+	"Disabled",
+	"Color Bar",
+	"Color Bar FADE",
+	"Random Data",
+	"Black White Square",
+	"Color Square"
+};
+
+static const int ov2685_test_pattern_val[] = {
+	OV2685_TEST_PATTERN_DISABLED,
+	OV2685_TEST_PATTERN_COLOR_BAR,
+	OV2685_TEST_PATTERN_COLOR_BAR_FADE,
+	OV2685_TEST_PATTERN_RANDOM,
+	OV2685_TEST_PATTERN_BW_SQUARE,
+	OV2685_TEST_PATTERN_COLOR_SQUARE,
+};
+
+static const struct ov2685_mode supported_modes[] = {
+	{
+		.width = 1600,
+		.height = 1200,
+		.exp_def = 0x04ee,
+		.hts_def = 0x06a4,
+		.vts_def = 0x050e,
+		.reg_list = ov2685_1600x1200_regs,
+	},
+};
+
+/* Write registers up to 4 at a time */
+static int ov2685_write_reg(struct i2c_client *client, u16 reg,
+			    u32 len, u32 val)
+{
+	u32 val_i, buf_i;
+	u8 buf[6];
+	u8 *val_p;
+	__be32 val_be;
+
+	if (len > 4)
+		return -EINVAL;
+
+	buf[0] = reg >> 8;
+	buf[1] = reg & 0xff;
+
+	val_be = cpu_to_be32(val);
+	val_p = (u8 *)&val_be;
+	buf_i = 2;
+	val_i = 4 - len;
+
+	while (val_i < 4)
+		buf[buf_i++] = val_p[val_i++];
+
+	if (i2c_master_send(client, buf, len + 2) != len + 2)
+		return -EIO;
+
+	return 0;
+}
+
+static int ov2685_write_array(struct i2c_client *client,
+			      const struct regval *regs)
+{
+	int ret = 0;
+	u32 i;
+
+	for (i = 0; ret == 0 && regs[i].addr != REG_NULL; i++)
+		ret = ov2685_write_reg(client, regs[i].addr,
+				       OV2685_REG_VALUE_08BIT, regs[i].val);
+
+	return ret;
+}
+
+/* Read registers up to 4 at a time */
+static int ov2685_read_reg(struct i2c_client *client, u16 reg,
+			   u32 len, u32 *val)
+{
+	struct i2c_msg msgs[2];
+	u8 *data_be_p;
+	__be32 data_be = 0;
+	__be16 reg_addr_be = cpu_to_be16(reg);
+	int ret;
+
+	if (len > 4)
+		return -EINVAL;
+
+	data_be_p = (u8 *)&data_be;
+	/* Write register address */
+	msgs[0].addr = client->addr;
+	msgs[0].flags = 0;
+	msgs[0].len = 2;
+	msgs[0].buf = (u8 *)&reg_addr_be;
+
+	/* Read data from register */
+	msgs[1].addr = client->addr;
+	msgs[1].flags = I2C_M_RD;
+	msgs[1].len = len;
+	msgs[1].buf = &data_be_p[4 - len];
+
+	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+	if (ret != ARRAY_SIZE(msgs))
+		return -EIO;
+
+	*val = be32_to_cpu(data_be);
+
+	return 0;
+}
+
+static void ov2685_fill_fmt(const struct ov2685_mode *mode,
+			    struct v4l2_mbus_framefmt *fmt)
+{
+	fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10;
+	fmt->width = mode->width;
+	fmt->height = mode->height;
+	fmt->field = V4L2_FIELD_NONE;
+}
+
+static int ov2685_set_fmt(struct v4l2_subdev *sd,
+			  struct v4l2_subdev_pad_config *cfg,
+			  struct v4l2_subdev_format *fmt)
+{
+	struct ov2685 *ov2685 = to_ov2685(sd);
+	struct v4l2_mbus_framefmt *mbus_fmt = &fmt->format;
+
+	/* only one mode supported for now */
+	ov2685_fill_fmt(ov2685->cur_mode, mbus_fmt);
+
+	return 0;
+}
+
+static int ov2685_get_fmt(struct v4l2_subdev *sd,
+			  struct v4l2_subdev_pad_config *cfg,
+			  struct v4l2_subdev_format *fmt)
+{
+	struct ov2685 *ov2685 = to_ov2685(sd);
+	struct v4l2_mbus_framefmt *mbus_fmt = &fmt->format;
+
+	ov2685_fill_fmt(ov2685->cur_mode, mbus_fmt);
+
+	return 0;
+}
+
+static int ov2685_enum_mbus_code(struct v4l2_subdev *sd,
+				 struct v4l2_subdev_pad_config *cfg,
+				 struct v4l2_subdev_mbus_code_enum *code)
+{
+	if (code->index >= ARRAY_SIZE(supported_modes))
+		return -EINVAL;
+
+	code->code = MEDIA_BUS_FMT_SBGGR10_1X10;
+
+	return 0;
+}
+
+static int ov2685_enum_frame_sizes(struct v4l2_subdev *sd,
+				   struct v4l2_subdev_pad_config *cfg,
+				   struct v4l2_subdev_frame_size_enum *fse)
+{
+	int index = fse->index;
+
+	if (index >= ARRAY_SIZE(supported_modes))
+		return -EINVAL;
+
+	fse->code = MEDIA_BUS_FMT_SBGGR10_1X10;
+
+	fse->min_width  = supported_modes[index].width;
+	fse->max_width  = supported_modes[index].width;
+	fse->max_height = supported_modes[index].height;
+	fse->min_height = supported_modes[index].height;
+
+	return 0;
+}
+
+/* Calculate the delay in us by clock rate and clock cycles */
+static inline u32 ov2685_cal_delay(u32 cycles)
+{
+	return DIV_ROUND_UP(cycles, OV2685_XVCLK_FREQ / 1000 / 1000);
+}
+
+static int __ov2685_power_on(struct ov2685 *ov2685)
+{
+	int ret;
+	u32 delay_us;
+	struct device *dev = &ov2685->client->dev;
+
+	ret = clk_prepare_enable(ov2685->xvclk);
+	if (ret < 0) {
+		dev_err(dev, "Failed to enable xvclk\n");
+		return ret;
+	}
+
+	gpiod_set_value_cansleep(ov2685->reset_gpio, 1);
+
+	ret = regulator_bulk_enable(OV2685_NUM_SUPPLIES, ov2685->supplies);
+	if (ret < 0) {
+		dev_err(dev, "Failed to enable regulators\n");
+		goto disable_clk;
+	}
+
+	/* The minimum delay between power supplies and reset rising can be 0 */
+	gpiod_set_value_cansleep(ov2685->reset_gpio, 0);
+	/* 8192 xvclk cycles prior to the first SCCB transaction */
+	delay_us = ov2685_cal_delay(8192);
+	usleep_range(delay_us, delay_us * 2);
+
+	/* HACK: ov2685 would output messy data after reset(R0103),
+	 * writing register before .s_stream() as a workaround
+	 */
+	ret = ov2685_write_array(ov2685->client, ov2685->cur_mode->reg_list);
+	if (ret)
+		goto disable_supplies;
+
+	return 0;
+
+disable_supplies:
+	regulator_bulk_disable(OV2685_NUM_SUPPLIES, ov2685->supplies);
+disable_clk:
+	clk_disable_unprepare(ov2685->xvclk);
+
+	return ret;
+}
+
+static void __ov2685_power_off(struct ov2685 *ov2685)
+{
+	/* 512 xvclk cycles after the last SCCB transaction or MIPI frame end */
+	u32 delay_us = ov2685_cal_delay(512);
+
+	usleep_range(delay_us, delay_us * 2);
+	clk_disable_unprepare(ov2685->xvclk);
+	gpiod_set_value_cansleep(ov2685->reset_gpio, 1);
+	regulator_bulk_disable(OV2685_NUM_SUPPLIES, ov2685->supplies);
+}
+
+static int ov2685_s_stream(struct v4l2_subdev *sd, int on)
+{
+	struct ov2685 *ov2685 = to_ov2685(sd);
+	struct i2c_client *client = ov2685->client;
+	int ret = 0;
+
+	mutex_lock(&ov2685->mutex);
+
+	on = !!on;
+	if (on == ov2685->streaming)
+		goto unlock_and_return;
+
+	if (on) {
+		ret = pm_runtime_get_sync(&ov2685->client->dev);
+		if (ret < 0) {
+			pm_runtime_put_noidle(&client->dev);
+			goto unlock_and_return;
+		}
+		ret = __v4l2_ctrl_handler_setup(&ov2685->ctrl_handler);
+		if (ret) {
+			pm_runtime_put(&client->dev);
+			goto unlock_and_return;
+		}
+		ret = ov2685_write_reg(client, REG_SC_CTRL_MODE,
+				OV2685_REG_VALUE_08BIT, SC_CTRL_MODE_STREAMING);
+		if (ret) {
+			pm_runtime_put(&client->dev);
+			goto unlock_and_return;
+		}
+	} else {
+		ov2685_write_reg(client, REG_SC_CTRL_MODE,
+				OV2685_REG_VALUE_08BIT, SC_CTRL_MODE_STANDBY);
+		pm_runtime_put(&ov2685->client->dev);
+	}
+
+	ov2685->streaming = on;
+
+unlock_and_return:
+	mutex_unlock(&ov2685->mutex);
+
+	return ret;
+}
+
+#ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
+static int ov2685_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	struct ov2685 *ov2685 = to_ov2685(sd);
+	struct v4l2_mbus_framefmt *try_fmt;
+
+	mutex_lock(&ov2685->mutex);
+
+	try_fmt = v4l2_subdev_get_try_format(sd, fh->pad, 0);
+	/* Initialize try_fmt */
+	ov2685_fill_fmt(&supported_modes[0], try_fmt);
+
+	mutex_unlock(&ov2685->mutex);
+
+	return 0;
+}
+#endif
+
+static int ov2685_runtime_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct ov2685 *ov2685 = to_ov2685(sd);
+
+	return __ov2685_power_on(ov2685);
+}
+
+static int ov2685_runtime_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct ov2685 *ov2685 = to_ov2685(sd);
+
+	__ov2685_power_off(ov2685);
+
+	return 0;
+}
+
+static const struct dev_pm_ops ov2685_pm_ops = {
+	SET_RUNTIME_PM_OPS(ov2685_runtime_suspend,
+			   ov2685_runtime_resume, NULL)
+};
+
+static int ov2685_set_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct ov2685 *ov2685 = container_of(ctrl->handler,
+					     struct ov2685, ctrl_handler);
+	struct i2c_client *client = ov2685->client;
+	s64 max_expo;
+	int ret;
+
+	/* Propagate change of current control to all related controls */
+	switch (ctrl->id) {
+	case V4L2_CID_VBLANK:
+		/* Update max exposure while meeting expected vblanking */
+		max_expo = ov2685->cur_mode->height + ctrl->val - 4;
+		__v4l2_ctrl_modify_range(ov2685->exposure,
+					 ov2685->exposure->minimum, max_expo,
+					 ov2685->exposure->step,
+					 ov2685->exposure->default_value);
+		break;
+	}
+
+	if (pm_runtime_get_if_in_use(&client->dev) <= 0)
+		return 0;
+
+	switch (ctrl->id) {
+	case V4L2_CID_EXPOSURE:
+		ret = ov2685_write_reg(ov2685->client, OV2685_REG_EXPOSURE,
+				       OV2685_REG_VALUE_24BIT, ctrl->val << 4);
+		break;
+	case V4L2_CID_ANALOGUE_GAIN:
+		ret = ov2685_write_reg(ov2685->client, OV2685_REG_GAIN,
+				       OV2685_REG_VALUE_16BIT, ctrl->val);
+		break;
+	case V4L2_CID_VBLANK:
+		ret = ov2685_write_reg(ov2685->client, OV2685_REG_VTS,
+				       OV2685_REG_VALUE_16BIT,
+				       ctrl->val + ov2685->cur_mode->height);
+		break;
+	case V4L2_CID_TEST_PATTERN:
+		ret = ov2685_write_reg(ov2685->client, OV2685_REG_TEST_PATTERN,
+				       OV2685_REG_VALUE_08BIT,
+				       ov2685_test_pattern_val[ctrl->val]);
+		break;
+	default:
+		dev_warn(&client->dev, "%s Unhandled id:0x%x, val:0x%x\n",
+			 __func__, ctrl->id, ctrl->val);
+		break;
+	};
+
+	pm_runtime_put(&client->dev);
+
+	return ret;
+}
+
+static const struct v4l2_subdev_video_ops ov2685_video_ops = {
+	.s_stream = ov2685_s_stream,
+};
+
+static const struct v4l2_subdev_pad_ops ov2685_pad_ops = {
+	.enum_mbus_code = ov2685_enum_mbus_code,
+	.enum_frame_size = ov2685_enum_frame_sizes,
+	.get_fmt = ov2685_get_fmt,
+	.set_fmt = ov2685_set_fmt,
+};
+
+static const struct v4l2_subdev_ops ov2685_subdev_ops = {
+	.video	= &ov2685_video_ops,
+	.pad	= &ov2685_pad_ops,
+};
+
+#ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
+static const struct v4l2_subdev_internal_ops ov2685_internal_ops = {
+	.open = ov2685_open,
+};
+#endif
+
+static const struct v4l2_ctrl_ops ov2685_ctrl_ops = {
+	.s_ctrl = ov2685_set_ctrl,
+};
+
+static int ov2685_initialize_controls(struct ov2685 *ov2685)
+{
+	const struct ov2685_mode *mode;
+	struct v4l2_ctrl_handler *handler;
+	struct v4l2_ctrl *ctrl;
+	u64 exposure_max;
+	u32 pixel_rate, h_blank;
+	int ret;
+
+	handler = &ov2685->ctrl_handler;
+	mode = ov2685->cur_mode;
+	ret = v4l2_ctrl_handler_init(handler, 8);
+	if (ret)
+		return ret;
+	handler->lock = &ov2685->mutex;
+
+	ctrl = v4l2_ctrl_new_int_menu(handler, NULL, V4L2_CID_LINK_FREQ,
+				      0, 0, link_freq_menu_items);
+	if (ctrl)
+		ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+
+	pixel_rate = (link_freq_menu_items[0] * 2 * OV2685_LANES) /
+		     OV2685_BITS_PER_SAMPLE;
+	v4l2_ctrl_new_std(handler, NULL, V4L2_CID_PIXEL_RATE,
+			  0, pixel_rate, 1, pixel_rate);
+
+	h_blank = mode->hts_def - mode->width;
+	ov2685->hblank = v4l2_ctrl_new_std(handler, NULL, V4L2_CID_HBLANK,
+				h_blank, h_blank, 1, h_blank);
+	if (ov2685->hblank)
+		ov2685->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+
+	ov2685->vblank = v4l2_ctrl_new_std(handler, &ov2685_ctrl_ops,
+				V4L2_CID_VBLANK, mode->vts_def - mode->height,
+				OV2685_VTS_MAX - mode->height, 1,
+				mode->vts_def - mode->height);
+
+	exposure_max = mode->vts_def - 4;
+	ov2685->exposure = v4l2_ctrl_new_std(handler, &ov2685_ctrl_ops,
+				V4L2_CID_EXPOSURE, OV2685_EXPOSURE_MIN,
+				exposure_max, OV2685_EXPOSURE_STEP,
+				mode->exp_def);
+
+	ov2685->anal_gain = v4l2_ctrl_new_std(handler, &ov2685_ctrl_ops,
+				V4L2_CID_ANALOGUE_GAIN, OV2685_GAIN_MIN,
+				OV2685_GAIN_MAX, OV2685_GAIN_STEP,
+				OV2685_GAIN_DEFAULT);
+
+	ov2685->test_pattern = v4l2_ctrl_new_std_menu_items(handler,
+				&ov2685_ctrl_ops, V4L2_CID_TEST_PATTERN,
+				ARRAY_SIZE(ov2685_test_pattern_menu) - 1,
+				0, 0, ov2685_test_pattern_menu);
+
+	if (handler->error) {
+		ret = handler->error;
+		dev_err(&ov2685->client->dev,
+			"Failed to init controls(%d)\n", ret);
+		goto err_free_handler;
+	}
+
+	ov2685->subdev.ctrl_handler = handler;
+
+	return 0;
+
+err_free_handler:
+	v4l2_ctrl_handler_free(handler);
+
+	return ret;
+}
+
+static int ov2685_check_sensor_id(struct ov2685 *ov2685,
+				  struct i2c_client *client)
+{
+	struct device *dev = &ov2685->client->dev;
+	int ret;
+	u32 id = 0;
+
+	ret = ov2685_read_reg(client, OV2685_REG_CHIP_ID,
+			      OV2685_REG_VALUE_16BIT, &id);
+	if (id != CHIP_ID) {
+		dev_err(dev, "Unexpected sensor id(%04x), ret(%d)\n", id, ret);
+		return ret;
+	}
+
+	dev_info(dev, "Detected OV%04x sensor\n", CHIP_ID);
+
+	return 0;
+}
+
+static int ov2685_configure_regulators(struct ov2685 *ov2685)
+{
+	int i;
+
+	for (i = 0; i < OV2685_NUM_SUPPLIES; i++)
+		ov2685->supplies[i].supply = ov2685_supply_names[i];
+
+	return devm_regulator_bulk_get(&ov2685->client->dev,
+				       OV2685_NUM_SUPPLIES,
+				       ov2685->supplies);
+}
+
+static int ov2685_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct ov2685 *ov2685;
+	int ret;
+
+	ov2685 = devm_kzalloc(dev, sizeof(*ov2685), GFP_KERNEL);
+	if (!ov2685)
+		return -ENOMEM;
+
+	ov2685->client = client;
+	ov2685->cur_mode = &supported_modes[0];
+
+	ov2685->xvclk = devm_clk_get(dev, "xvclk");
+	if (IS_ERR(ov2685->xvclk)) {
+		dev_err(dev, "Failed to get xvclk\n");
+		return -EINVAL;
+	}
+	ret = clk_set_rate(ov2685->xvclk, OV2685_XVCLK_FREQ);
+	if (ret < 0) {
+		dev_err(dev, "Failed to set xvclk rate (24MHz)\n");
+		return ret;
+	}
+	if (clk_get_rate(ov2685->xvclk) != OV2685_XVCLK_FREQ)
+		dev_warn(dev, "xvclk mismatched, modes are based on 24MHz\n");
+
+	ov2685->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(ov2685->reset_gpio)) {
+		dev_err(dev, "Failed to get reset-gpios\n");
+		return -EINVAL;
+	}
+
+	ret = ov2685_configure_regulators(ov2685);
+	if (ret) {
+		dev_err(dev, "Failed to get power regulators\n");
+		return ret;
+	}
+
+	mutex_init(&ov2685->mutex);
+	v4l2_i2c_subdev_init(&ov2685->subdev, client, &ov2685_subdev_ops);
+	ret = ov2685_initialize_controls(ov2685);
+	if (ret)
+		goto err_destroy_mutex;
+
+	ret = __ov2685_power_on(ov2685);
+	if (ret)
+		goto err_free_handler;
+
+	ret = ov2685_check_sensor_id(ov2685, client);
+	if (ret)
+		goto err_power_off;
+
+#ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
+	ov2685->subdev.internal_ops = &ov2685_internal_ops;
+	ov2685->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+#endif
+#if defined(CONFIG_MEDIA_CONTROLLER)
+	ov2685->pad.flags = MEDIA_PAD_FL_SOURCE;
+	ov2685->subdev.entity.function = MEDIA_ENT_F_CAM_SENSOR;
+	ret = media_entity_pads_init(&ov2685->subdev.entity, 1, &ov2685->pad);
+	if (ret < 0)
+		goto err_power_off;
+#endif
+
+	ret = v4l2_async_register_subdev(&ov2685->subdev);
+	if (ret) {
+		dev_err(dev, "v4l2 async register subdev failed\n");
+		goto err_clean_entity;
+	}
+
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	pm_runtime_idle(dev);
+
+	return 0;
+
+err_clean_entity:
+#if defined(CONFIG_MEDIA_CONTROLLER)
+	media_entity_cleanup(&ov2685->subdev.entity);
+#endif
+err_power_off:
+	__ov2685_power_off(ov2685);
+err_free_handler:
+	v4l2_ctrl_handler_free(&ov2685->ctrl_handler);
+err_destroy_mutex:
+	mutex_destroy(&ov2685->mutex);
+
+	return ret;
+}
+
+static int ov2685_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct ov2685 *ov2685 = to_ov2685(sd);
+
+	v4l2_async_unregister_subdev(sd);
+#if defined(CONFIG_MEDIA_CONTROLLER)
+	media_entity_cleanup(&sd->entity);
+#endif
+	v4l2_ctrl_handler_free(&ov2685->ctrl_handler);
+	mutex_destroy(&ov2685->mutex);
+
+	pm_runtime_disable(&client->dev);
+	if (!pm_runtime_status_suspended(&client->dev))
+		__ov2685_power_off(ov2685);
+	pm_runtime_set_suspended(&client->dev);
+
+	return 0;
+}
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id ov2685_of_match[] = {
+	{ .compatible = "ovti,ov2685" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ov2685_of_match);
+#endif
+
+static struct i2c_driver ov2685_i2c_driver = {
+	.driver = {
+		.name = "ov2685",
+		.owner = THIS_MODULE,
+		.pm = &ov2685_pm_ops,
+		.of_match_table = of_match_ptr(ov2685_of_match),
+	},
+	.probe		= &ov2685_probe,
+	.remove		= &ov2685_remove,
+};
+
+module_i2c_driver(ov2685_i2c_driver);
+
+MODULE_DESCRIPTION("OmniVision ov2685 sensor driver");
+MODULE_LICENSE("GPL v2");