Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Rui Miguel Silva <rmfrfs@gmail.com>
To:     mchehab@kernel.org, sakari.ailus@linux.intel.com,
        hverkuil@xs4all.nl
Cc:     linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        Ryan Harkin <ryan.harkin@linaro.org>,
        Rui Miguel Silva <rui.silva@linaro.org>
Subject: [PATCH 2/2] media: ov2680: Add Omnivision OV2680 sensor driver
Date:   Thu, 22 Feb 2018 10:23:38 +0000
Message-Id: <20180222102338.28896-3-rui.silva@linaro.org>
In-Reply-To: <20180222102338.28896-1-rui.silva@linaro.org>
References: <20180222102338.28896-1-rui.silva@linaro.org>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

This patch adds V4L2 sub-device driver for OV2680 image sensor.
The OV2680 is a 1/5" CMOS color sensor from Omnivision.
Supports output format: 10-bit Raw RGB.
The OV2680 has a single lane MIPI interface.

The driver exposes following V4L2 controls:
- auto/manual exposure,
- exposure,
- auto/manual gain,
- gain,
- horizontal/vertical flip,
- test pattern menu.
Supported resolution are only: QUXGA, 720P, UXGA.

Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
---
 drivers/media/i2c/Kconfig  |   13 +
 drivers/media/i2c/Makefile |    1 +
 drivers/media/i2c/ov2680.c | 1189 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 1203 insertions(+)
 create mode 100644 drivers/media/i2c/ov2680.c

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 9f18cd296841..089103d29171 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -586,6 +586,19 @@ config VIDEO_OV2659
 	  To compile this driver as a module, choose M here: the
 	  module will be called ov2659.
 
+config VIDEO_OV2680
+	tristate "OmniVision OV2680 sensor support"
+	depends on OF
+	depends on GPIOLIB && VIDEO_V4L2 && I2C && VIDEO_V4L2_SUBDEV_API
+	depends on MEDIA_CAMERA_SUPPORT
+	select V4L2_FWNODE
+	---help---
+	  This is a Video4Linux2 sensor-level driver for the OmniVision
+	  OV2680 camera sensor with a MIPI CSI-2 interface.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ov2680.
+
 config VIDEO_OV5640
 	tristate "OmniVision OV5640 sensor support"
 	depends on OF
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index c0f94cd8d56d..d0aba4d37b8d 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -61,6 +61,7 @@ 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-$(CONFIG_VIDEO_OV2680) += ov2680.o
 obj-$(CONFIG_VIDEO_OV5640) += ov5640.o
 obj-$(CONFIG_VIDEO_OV5645) += ov5645.o
 obj-$(CONFIG_VIDEO_OV5647) += ov5647.o
diff --git a/drivers/media/i2c/ov2680.c b/drivers/media/i2c/ov2680.c
new file mode 100644
index 000000000000..64c1c2b03f97
--- /dev/null
+++ b/drivers/media/i2c/ov2680.c
@@ -0,0 +1,1189 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Omnivision OV2680 CMOS Image Sensor driver
+ *
+ * Copyright (C) 2018 Linaro Ltd
+ *
+ * Based on OV5640 Sensor Driver
+ * Copyright (C) 2011-2013 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright (C) 2014-2017 Mentor Graphics Inc.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+
+#include <media/v4l2-common.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-image-sizes.h>
+#include <media/v4l2-mediabus.h>
+#include <media/v4l2-subdev.h>
+
+#define OV2680_XVCLK_MIN	6000000
+#define OV2680_XVCLK_MAX	24000000
+
+#define OV2680_CHIP_ID_HIGH	0x26
+#define OV2680_CHIP_ID_LOW	0x80
+
+#define OV2680_REG_STREAM_CTRL		0x0100
+#define OV2680_REG_SOFT_RESET		0x0103
+
+#define OV2680_REG_CHIP_ID_HIGH		0x300a
+#define OV2680_REG_CHIP_ID_LOW		0x300b
+
+#define OV2680_REG_R_MANUAL		0x3503
+#define OV2680_REG_GAIN_PK		0x350a
+#define OV2680_REG_EXPOSURE_PK_HIGH	0x3500
+#define OV2680_REG_EXPOSURE_PK_MED	0x3501
+#define OV2680_REG_EXPOSURE_PK_LOW	0x3502
+#define OV2680_REG_TIMING_HTS		0x380c
+#define OV2680_REG_TIMING_VTS		0x380e
+#define OV2680_REG_FORMAT1		0x3820
+#define OV2680_REG_FORMAT2		0x3821
+
+#define OV2680_REG_ISP_CTRL00		0x5080
+
+enum ov2680_frame_rate {
+	OV2680_30_FPS,
+	OV2680_FRAMERATES_MAX,
+};
+
+static const int ov2680_framerates[] = {
+	[OV2680_30_FPS] = 30,
+};
+
+enum ov2680_mode_id {
+	OV2680_MODE_QUXGA_800_600,
+	OV2680_MODE_720P_1280_720,
+	OV2680_MODE_UXGA_1600_1200,
+	OV2680_MODE_MAX,
+};
+
+struct reg_value {
+	u16 reg_addr;
+	u8 val;
+};
+
+struct ov2680_mode_info {
+	const char *name;
+	enum ov2680_mode_id id;
+	u32 width;
+	u32 height;
+	const struct reg_value *reg_data;
+	u32 reg_data_size;
+};
+
+struct ov2680_ctrls {
+	struct v4l2_ctrl_handler handler;
+	struct {
+		struct v4l2_ctrl *auto_exp;
+		struct v4l2_ctrl *exposure;
+	};
+	struct {
+		struct v4l2_ctrl *auto_gain;
+		struct v4l2_ctrl *gain;
+	};
+
+	struct v4l2_ctrl *hflip;
+	struct v4l2_ctrl *vflip;
+	struct v4l2_ctrl *test_pattern;
+};
+
+struct ov2680_dev {
+	struct i2c_client		*i2c_client;
+	struct v4l2_subdev		sd;
+
+	struct media_pad		pad;
+	struct v4l2_fwnode_endpoint	ep;
+	struct clk			*xvclk;
+	u32				xvclk_freq;
+
+	struct gpio_desc		*pwdn_gpio;
+	struct mutex			lock; /* protect members */
+
+	bool				mode_pending_changes;
+	bool				is_enabled;
+	bool				is_streaming;
+
+	struct ov2680_ctrls		ctrls;
+	struct v4l2_mbus_framefmt	fmt;
+	struct v4l2_fract		frame_interval;
+
+	enum ov2680_frame_rate		current_fps;
+	const struct ov2680_mode_info	*current_mode;
+};
+
+static const char * const test_pattern_menu[] = {
+	"Disabled",
+	"Color bars",
+	"Random Data",
+	"Square",
+	"Black Image",
+};
+
+static const struct reg_value ov2680_setting_30fps_QUXGA_800_600[] = {
+	{0x3086, 0x01}, {0x370a, 0x23}, {0x3808, 0x03}, {0x3809, 0x20},
+	{0x380a, 0x02}, {0x380b, 0x58}, {0x380c, 0x06}, {0x380d, 0xac},
+	{0x380e, 0x02}, {0x380f, 0x84}, {0x3811, 0x04}, {0x3813, 0x04},
+	{0x3814, 0x31}, {0x3815, 0x31}, {0x3820, 0xc0}, {0x4008, 0x00},
+	{0x4009, 0x03}, {0x4837, 0x1e}, {0x3501, 0x4e}, {0x3502, 0xe0},
+};
+
+static const struct reg_value ov2680_setting_30fps_720P_1280_720[] = {
+	{0x3086, 0x00}, {0x3808, 0x05}, {0x3809, 0x00}, {0x380a, 0x02},
+	{0x380b, 0xd0}, {0x380c, 0x06}, {0x380d, 0xa8}, {0x380e, 0x05},
+	{0x380f, 0x0e}, {0x3811, 0x08}, {0x3813, 0x06}, {0x3814, 0x11},
+	{0x3815, 0x11}, {0x3820, 0xc0}, {0x4008, 0x00},
+};
+
+static const struct reg_value ov2680_setting_30fps_UXGA_1600_1200[] = {
+	{0x3086, 0x00}, {0x3501, 0x4e}, {0x3502, 0xe0}, {0x3808, 0x06},
+	{0x3809, 0x40}, {0x380a, 0x04}, {0x380b, 0xb0}, {0x380c, 0x06},
+	{0x380d, 0xa8}, {0x380e, 0x05}, {0x380f, 0x0e}, {0x3811, 0x00},
+	{0x3813, 0x00}, {0x3814, 0x11}, {0x3815, 0x11}, {0x3820, 0xc0},
+	{0x4008, 0x00}, {0x4837, 0x18}
+};
+
+static const struct ov2680_mode_info ov2680_mode_init_data = {
+	"mode_quxga_800_600", OV2680_MODE_QUXGA_800_600, 800, 600,
+	ov2680_setting_30fps_QUXGA_800_600,
+	ARRAY_SIZE(ov2680_setting_30fps_QUXGA_800_600),
+};
+
+static const struct ov2680_mode_info
+ov2680_mode_data[OV2680_FRAMERATES_MAX][OV2680_MODE_MAX] = {
+	{
+		{"mode_quxga_800_600", OV2680_MODE_QUXGA_800_600,
+		 800, 600, ov2680_setting_30fps_QUXGA_800_600,
+		 ARRAY_SIZE(ov2680_setting_30fps_QUXGA_800_600)},
+		{"mode_720p_1280_720", OV2680_MODE_720P_1280_720,
+		 1280, 720, ov2680_setting_30fps_720P_1280_720,
+		 ARRAY_SIZE(ov2680_setting_30fps_720P_1280_720)},
+		{"mode_uxga_1600_1200", OV2680_MODE_UXGA_1600_1200,
+		 1600, 1200, ov2680_setting_30fps_UXGA_1600_1200,
+		 ARRAY_SIZE(ov2680_setting_30fps_UXGA_1600_1200)},
+	},
+};
+
+static struct ov2680_dev *to_ov2680_dev(struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct ov2680_dev, sd);
+}
+
+static struct device *ov2680_to_dev(struct ov2680_dev *sensor)
+{
+	return &sensor->i2c_client->dev;
+}
+
+static inline struct v4l2_subdev *ctrl_to_sd(struct v4l2_ctrl *ctrl)
+{
+	return &container_of(ctrl->handler, struct ov2680_dev,
+			     ctrls.handler)->sd;
+}
+
+static int ov2680_write_reg(struct ov2680_dev *sensor, u16 reg, u8 val)
+{
+	struct i2c_client *client = sensor->i2c_client;
+	struct i2c_msg msg;
+	u8 buf[3];
+	int ret;
+
+	buf[0] = reg >> 8;
+	buf[1] = reg & 0xff;
+	buf[2] = val;
+
+	msg.addr = client->addr;
+	msg.flags = client->flags;
+	msg.buf = buf;
+	msg.len = sizeof(buf);
+
+	ret = i2c_transfer(client->adapter, &msg, 1);
+	if (ret < 0) {
+		dev_err(&client->dev, "write error: reg=0x%4x: %d\n", reg, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int ov2680_write_reg16(struct ov2680_dev *sensor, u16 reg, u16 val)
+{
+	int ret;
+
+	ret = ov2680_write_reg(sensor, reg, val >> 8);
+	if (ret)
+		return ret;
+
+	return ov2680_write_reg(sensor, reg + 1, val & 0xff);
+}
+
+static int ov2680_read_reg(struct ov2680_dev *sensor, u16 reg, u8 *val)
+{
+	struct i2c_client *client = sensor->i2c_client;
+	struct i2c_msg msg[2];
+	u8 buf[2];
+	int ret;
+
+	buf[0] = reg >> 8;
+	buf[1] = reg & 0xff;
+
+	msg[0].addr = client->addr;
+	msg[0].flags = client->flags;
+	msg[0].buf = buf;
+	msg[0].len = sizeof(buf);
+
+	msg[1].addr = client->addr;
+	msg[1].flags = client->flags | I2C_M_RD;
+	msg[1].buf = buf;
+	msg[1].len = 1;
+
+	ret = i2c_transfer(client->adapter, msg, 2);
+	if (ret < 0) {
+		dev_err(&client->dev, "read error: reg=0x%4x: %d\n", reg, ret);
+		return ret;
+	}
+
+	*val = buf[0];
+	return 0;
+}
+
+static int ov2680_read_reg16(struct ov2680_dev *sensor, u16 reg, u16 *val)
+{
+	u8 hi, lo;
+	int ret;
+
+	ret = ov2680_read_reg(sensor, reg, &hi);
+	if (ret)
+		return ret;
+	ret = ov2680_read_reg(sensor, reg + 1, &lo);
+	if (ret)
+		return ret;
+
+	*val = ((u16)hi << 8) | (u16)lo;
+
+	return 0;
+}
+
+static int ov2680_mod_reg(struct ov2680_dev *sensor, u16 reg, u8 mask, u8 val)
+{
+	u8 readval;
+	int ret;
+
+	ret = ov2680_read_reg(sensor, reg, &readval);
+	if (ret < 0)
+		return ret;
+
+	readval &= ~mask;
+	val &= mask;
+	val |= readval;
+
+	return ov2680_write_reg(sensor, reg, val);
+}
+
+static int ov2680_load_regs(struct ov2680_dev *sensor,
+			    const struct ov2680_mode_info *mode)
+{
+	const struct reg_value *regs = mode->reg_data;
+	unsigned int i;
+	int ret = 0;
+	u16 reg_addr;
+	u8 val;
+
+	for (i = 0; i < mode->reg_data_size; ++i, ++regs) {
+		reg_addr = regs->reg_addr;
+		val = regs->val;
+
+		ret = ov2680_write_reg(sensor, reg_addr, val);
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+static void ov2680_power_up(struct ov2680_dev *sensor)
+{
+	if (!sensor->pwdn_gpio)
+		return;
+
+	gpiod_set_value(sensor->pwdn_gpio, 1);
+	usleep_range(5000, 10000);
+}
+
+static void ov2680_power_down(struct ov2680_dev *sensor)
+{
+	if (!sensor->pwdn_gpio)
+		return;
+
+	gpiod_set_value(sensor->pwdn_gpio, 0);
+	usleep_range(5000, 10000);
+}
+
+static int ov2680_soft_reset(struct ov2680_dev *sensor)
+{
+	struct device *dev = ov2680_to_dev(sensor);
+	int ret;
+
+	ret = ov2680_write_reg(sensor, OV2680_REG_SOFT_RESET, 0x01);
+	if (ret != 0) {
+		dev_err(dev, "sensor soft reset failed\n");
+		return ret;
+	}
+	usleep_range(1000, 2000);
+	return 0;
+}
+
+static void ov2680_reset(struct ov2680_dev *sensor)
+{
+	if (!sensor->pwdn_gpio) {
+		ov2680_soft_reset(sensor);
+		return;
+	}
+
+	ov2680_power_down(sensor);
+	ov2680_power_up(sensor);
+}
+
+static int ov2680_vflip_enable(struct ov2680_dev *sensor)
+{
+	return ov2680_mod_reg(sensor, OV2680_REG_FORMAT1, BIT(2), BIT(2));
+}
+
+static int ov2680_vflip_disable(struct ov2680_dev *sensor)
+{
+	return ov2680_mod_reg(sensor, OV2680_REG_FORMAT1, BIT(2), 0);
+}
+
+static int ov2680_hflip_enable(struct ov2680_dev *sensor)
+{
+	return ov2680_mod_reg(sensor, OV2680_REG_FORMAT2, BIT(2), BIT(2));
+}
+
+static int ov2680_hflip_disable(struct ov2680_dev *sensor)
+{
+	return ov2680_mod_reg(sensor, OV2680_REG_FORMAT2, BIT(2), 0);
+}
+
+static int ov2680_test_pattern_set(struct ov2680_dev *sensor, int value)
+{
+	int ret;
+
+	if (!value)
+		return ov2680_mod_reg(sensor, OV2680_REG_ISP_CTRL00, BIT(7), 0);
+
+	ret = ov2680_mod_reg(sensor, OV2680_REG_ISP_CTRL00, 0x03, value - 1);
+	if (ret < 0)
+		return ret;
+
+	ret = ov2680_mod_reg(sensor, OV2680_REG_ISP_CTRL00, BIT(7), BIT(7));
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int ov2680_gain_set(struct ov2680_dev *sensor, bool auto_gain)
+{
+	struct ov2680_ctrls *ctrls = &sensor->ctrls;
+	u16 gain;
+	int ret;
+
+	ret = ov2680_mod_reg(sensor, OV2680_REG_R_MANUAL, BIT(1),
+			     auto_gain ? 0 : BIT(1));
+	if (ret < 0)
+		return ret;
+
+	if (auto_gain)
+		return 0;
+
+	gain = (u16)ctrls->gain->val;
+
+	ret = ov2680_write_reg16(sensor, OV2680_REG_GAIN_PK, gain & 0x7ff);
+
+	return 0;
+}
+
+static int ov2680_gain_get(struct ov2680_dev *sensor)
+{
+	u16 gain;
+	int ret;
+
+	ret = ov2680_read_reg16(sensor, OV2680_REG_GAIN_PK, &gain);
+	if (ret)
+		return ret;
+
+	return gain & 0x3ff;
+}
+
+static int ov2680_auto_gain_enable(struct ov2680_dev *sensor)
+{
+	return ov2680_gain_set(sensor, true);
+}
+
+static int ov2680_auto_gain_disable(struct ov2680_dev *sensor)
+{
+	return ov2680_gain_set(sensor, false);
+}
+
+static int ov2680_exposure_set(struct ov2680_dev *sensor, bool auto_exp)
+{
+	struct ov2680_ctrls *ctrls = &sensor->ctrls;
+	u32 exp;
+	int ret;
+
+	ret = ov2680_mod_reg(sensor, OV2680_REG_R_MANUAL, BIT(0),
+			     auto_exp ? 0 : BIT(0));
+	if (ret < 0)
+		return ret;
+
+	if (auto_exp)
+		return 0;
+
+	exp = (u32)ctrls->exposure->val;
+	exp <<= 4;
+
+	ret = ov2680_write_reg(sensor, OV2680_REG_EXPOSURE_PK_LOW, exp & 0xf0);
+	if (ret)
+		return ret;
+
+	ret = ov2680_write_reg(sensor, OV2680_REG_EXPOSURE_PK_MED,
+			       (exp >> 8) & 0xff);
+	if (ret)
+		return ret;
+
+	return ov2680_write_reg(sensor, OV2680_REG_EXPOSURE_PK_HIGH,
+				(exp >> 16) & 0x0f);
+}
+
+static int ov2680_exposure_get(struct ov2680_dev *sensor)
+{
+	int exp, ret;
+	u8 temp;
+
+	ret = ov2680_read_reg(sensor, OV2680_REG_EXPOSURE_PK_HIGH, &temp);
+	if (ret)
+		return ret;
+	exp = ((int)temp & 0x0f) << 16;
+
+	ret = ov2680_read_reg(sensor, OV2680_REG_EXPOSURE_PK_MED, &temp);
+	if (ret)
+		return ret;
+	exp |= ((int)temp & 0xff) << 8;
+
+	ret = ov2680_read_reg(sensor, OV2680_REG_EXPOSURE_PK_LOW, &temp);
+	if (ret)
+		return ret;
+	exp |= ((int)temp & 0xf0);
+
+	return exp >> 4;
+}
+
+static int ov2680_auto_exposure_enable(struct ov2680_dev *sensor)
+{
+	return ov2680_exposure_set(sensor, true);
+}
+
+static int ov2680_auto_exposure_disable(struct ov2680_dev *sensor)
+{
+	return ov2680_exposure_set(sensor, false);
+}
+
+static int ov2680_stream_enable(struct ov2680_dev *sensor)
+{
+	return ov2680_write_reg(sensor, OV2680_REG_STREAM_CTRL, 1);
+}
+
+static int ov2680_stream_disable(struct ov2680_dev *sensor)
+{
+	return ov2680_write_reg(sensor, OV2680_REG_STREAM_CTRL, 0);
+}
+
+static int ov2680_mode_set_direct(struct ov2680_dev *sensor)
+{
+	int ret;
+
+	if (!sensor->current_mode->reg_data)
+		return -EINVAL;
+
+	ret = ov2680_load_regs(sensor, sensor->current_mode);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int ov2680_mode_set(struct ov2680_dev *sensor)
+{
+	int ret;
+
+	ret = ov2680_auto_gain_disable(sensor);
+	if (ret < 0)
+		return ret;
+
+	ret = ov2680_auto_exposure_disable(sensor);
+	if (ret < 0)
+		return ret;
+
+	ret = ov2680_mode_set_direct(sensor);
+	if (ret < 0)
+		return ret;
+
+	ret = ov2680_auto_gain_enable(sensor);
+	if (ret < 0)
+		return ret;
+
+	ret = ov2680_auto_exposure_enable(sensor);
+	if (ret < 0)
+		return ret;
+
+	sensor->mode_pending_changes = false;
+
+	return 0;
+}
+
+static int ov2680_mode_restore(struct ov2680_dev *sensor)
+{
+	int ret;
+
+	ret = ov2680_load_regs(sensor, &ov2680_mode_init_data);
+	if (ret < 0)
+		return ret;
+
+	return ov2680_mode_set(sensor);
+}
+
+static int ov2680_disable(struct ov2680_dev *sensor)
+{
+	if (!sensor->is_enabled)
+		return 0;
+
+	clk_disable_unprepare(sensor->xvclk);
+	ov2680_power_down(sensor);
+	sensor->is_enabled = false;
+
+	return 0;
+}
+
+static int ov2680_enable(struct ov2680_dev *sensor)
+{
+	struct device *dev = ov2680_to_dev(sensor);
+	int ret;
+
+	if (sensor->is_enabled)
+		return 0;
+
+	ov2680_reset(sensor);
+
+	ret = clk_prepare_enable(sensor->xvclk);
+	if (ret < 0)
+		return ret;
+
+	ret = ov2680_mode_restore(sensor);
+	if (ret < 0)
+		goto disable;
+
+	sensor->is_enabled = true;
+
+	/* Set clock lane into LP-11 state */
+	ov2680_stream_enable(sensor);
+	usleep_range(1000, 2000);
+	ov2680_stream_disable(sensor);
+
+	return 0;
+
+disable:
+	dev_err(dev, "failed to enable sensor: %d\n", ret);
+	ov2680_disable(sensor);
+
+	return ret;
+}
+
+static int ov2680_s_power(struct v4l2_subdev *sd, int on)
+{
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+	int ret = 0;
+
+	mutex_lock(&sensor->lock);
+
+	if (on)
+		ret = ov2680_enable(sensor);
+	else
+		ret = ov2680_disable(sensor);
+
+	mutex_unlock(&sensor->lock);
+
+	if (on && ret == 0) {
+		ret = v4l2_ctrl_handler_setup(&sensor->ctrls.handler);
+		if (ret < 0)
+			return ret;
+	}
+
+	return ret;
+}
+
+static int ov2680_g_frame_interval(struct v4l2_subdev *sd,
+				   struct v4l2_subdev_frame_interval *fi)
+{
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+
+	mutex_lock(&sensor->lock);
+	fi->interval = sensor->frame_interval;
+	mutex_unlock(&sensor->lock);
+
+	return 0;
+}
+
+static int ov2680_s_frame_interval(struct v4l2_subdev *sd,
+				   struct v4l2_subdev_frame_interval *fi)
+{
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+
+	if (fi->interval.denominator != sensor->frame_interval.denominator ||
+	    fi->interval.numerator != sensor->frame_interval.numerator)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int ov2680_s_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+	int ret = 0;
+
+	mutex_lock(&sensor->lock);
+
+	if (sensor->is_streaming == !!enable)
+		goto unlock;
+
+	if (enable && sensor->mode_pending_changes) {
+		ret = ov2680_mode_set(sensor);
+		if (ret < 0)
+			goto unlock;
+	}
+
+	if (enable)
+		ret = ov2680_stream_enable(sensor);
+	else
+		ret = ov2680_stream_disable(sensor);
+
+	sensor->is_streaming = !!enable;
+
+unlock:
+	mutex_unlock(&sensor->lock);
+
+	return ret;
+}
+
+static int ov2680_enum_mbus_code(struct v4l2_subdev *sd,
+				 struct v4l2_subdev_pad_config *cfg,
+				 struct v4l2_subdev_mbus_code_enum *code)
+{
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+
+	if (code->pad != 0 || code->index != 0)
+		return -EINVAL;
+
+	code->code = sensor->fmt.code;
+
+	return 0;
+}
+
+static int ov2680_get_fmt(struct v4l2_subdev *sd,
+			  struct v4l2_subdev_pad_config *cfg,
+			  struct v4l2_subdev_format *format)
+{
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+	struct v4l2_mbus_framefmt *fmt;
+
+	if (format->pad != 0)
+		return -EINVAL;
+
+	mutex_lock(&sensor->lock);
+
+	if (format->which == V4L2_SUBDEV_FORMAT_TRY)
+		fmt = v4l2_subdev_get_try_format(&sensor->sd, cfg, format->pad);
+	else
+		fmt = &sensor->fmt;
+
+	format->format = *fmt;
+
+	mutex_unlock(&sensor->lock);
+
+	return 0;
+}
+
+static const struct ov2680_mode_info *
+ov2680_mode_find(struct ov2680_dev *sensor, enum ov2680_frame_rate fps,
+		 int width, int height)
+{
+	const struct ov2680_mode_info *mode = NULL;
+	bool mode_found = false;
+	int i;
+
+	for (i = OV2680_MODE_MAX - 1; i >= 0; i--) {
+		mode = &ov2680_mode_data[fps][i];
+
+		if (!mode->reg_data)
+			continue;
+
+		if (mode->width == width && mode->height == height) {
+			mode_found = true;
+			break;
+		}
+	}
+
+	return mode_found ? mode : NULL;
+}
+
+static int ov2680_set_fmt(struct v4l2_subdev *sd,
+			  struct v4l2_subdev_pad_config *cfg,
+			  struct v4l2_subdev_format *format)
+{
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+	struct v4l2_mbus_framefmt *fmt = &format->format;
+	const struct ov2680_mode_info *mode;
+	int ret = 0;
+
+	if (format->pad != 0)
+		return -EINVAL;
+
+	mutex_lock(&sensor->lock);
+
+	if (sensor->is_streaming) {
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	mode = ov2680_mode_find(sensor, sensor->current_fps, fmt->width,
+				fmt->height);
+	if (!mode) {
+		ret = -EINVAL;
+		goto unlock;
+	}
+
+	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
+		fmt = v4l2_subdev_get_try_format(sd, cfg, 0);
+
+		*fmt = format->format;
+		goto unlock;
+	}
+
+	fmt->width = mode->width;
+	fmt->height = mode->height;
+	fmt->code = sensor->fmt.code;
+	fmt->colorspace = sensor->fmt.colorspace;
+
+	sensor->current_mode = mode;
+	sensor->fmt = format->format;
+	sensor->mode_pending_changes = true;
+
+unlock:
+	mutex_unlock(&sensor->lock);
+
+	return ret;
+}
+
+static int ov2680_enum_frame_size(struct v4l2_subdev *sd,
+				  struct v4l2_subdev_pad_config *cfg,
+				  struct v4l2_subdev_frame_size_enum *fse)
+{
+	int index = fse->index;
+
+	if (index >= OV2680_MODE_MAX)
+		return -EINVAL;
+
+	fse->min_width = ov2680_mode_data[0][index].width;
+	fse->min_height = ov2680_mode_data[0][index].height;
+	fse->max_width = ov2680_mode_data[0][index].width;
+	fse->max_height = ov2680_mode_data[0][index].height;
+
+	return 0;
+}
+
+static int ov2680_enum_frame_interval(struct v4l2_subdev *sd,
+			      struct v4l2_subdev_pad_config *cfg,
+			      struct v4l2_subdev_frame_interval_enum *fie)
+{
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+	const struct ov2680_mode_info *mode;
+	struct v4l2_fract tpf;
+
+	if (fie->index >= OV2680_FRAMERATES_MAX)
+		return -EINVAL;
+
+	tpf.denominator = ov2680_framerates[fie->index];
+	tpf.numerator = 1;
+
+	fie->interval = tpf;
+
+	mode = ov2680_mode_find(sensor, sensor->current_fps, fie->width,
+				fie->height);
+
+	return mode ? 0 : -EINVAL;
+}
+
+static int ov2680_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+	int val;
+
+	if (!sensor->is_enabled)
+		return 0;
+
+	switch (ctrl->id) {
+	case V4L2_CID_AUTOGAIN:
+		if (!ctrl->val)
+			return 0;
+		val = ov2680_gain_get(sensor);
+		if (val < 0)
+			return val;
+		sensor->ctrls.gain->val = val;
+		break;
+	case V4L2_CID_EXPOSURE_AUTO:
+		if (ctrl->val == V4L2_EXPOSURE_MANUAL)
+			return 0;
+		val = ov2680_exposure_get(sensor);
+		if (val < 0)
+			return val;
+		sensor->ctrls.exposure->val = val;
+		break;
+	}
+
+	return 0;
+}
+
+static int ov2680_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+
+	if (!sensor->is_enabled)
+		return 0;
+
+	switch (ctrl->id) {
+	case V4L2_CID_AUTOGAIN:
+		return ov2680_gain_set(sensor, !!ctrl->val);
+	case V4L2_CID_EXPOSURE_AUTO:
+		return ov2680_exposure_set(sensor, !!ctrl->val);
+	case V4L2_CID_VFLIP:
+		if (ctrl->val)
+			return ov2680_vflip_enable(sensor);
+		else
+			return ov2680_vflip_disable(sensor);
+	case V4L2_CID_HFLIP:
+		if (ctrl->val)
+			return ov2680_hflip_enable(sensor);
+		else
+			return ov2680_hflip_disable(sensor);
+	case V4L2_CID_TEST_PATTERN:
+		return ov2680_test_pattern_set(sensor, ctrl->val);
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static const struct v4l2_ctrl_ops ov2680_ctrl_ops = {
+	.g_volatile_ctrl = ov2680_g_volatile_ctrl,
+	.s_ctrl = ov2680_s_ctrl,
+};
+
+static const struct v4l2_subdev_core_ops ov2680_core_ops = {
+	.s_power = ov2680_s_power,
+};
+
+static const struct v4l2_subdev_video_ops ov2680_video_ops = {
+	.g_frame_interval	= ov2680_g_frame_interval,
+	.s_frame_interval	= ov2680_s_frame_interval,
+	.s_stream		= ov2680_s_stream,
+};
+
+static const struct v4l2_subdev_pad_ops ov2680_pad_ops = {
+	.enum_mbus_code		= ov2680_enum_mbus_code,
+	.get_fmt		= ov2680_get_fmt,
+	.set_fmt		= ov2680_set_fmt,
+	.enum_frame_size	= ov2680_enum_frame_size,
+	.enum_frame_interval	= ov2680_enum_frame_interval,
+};
+
+static const struct v4l2_subdev_ops ov2680_subdev_ops = {
+	.core	= &ov2680_core_ops,
+	.video	= &ov2680_video_ops,
+	.pad	= &ov2680_pad_ops,
+};
+
+static int ov2680_mode_init(struct ov2680_dev *sensor)
+{
+	const struct ov2680_mode_info *init_mode;
+
+	/* set initial mode */
+	sensor->fmt.code = MEDIA_BUS_FMT_SBGGR10_1X10;
+	sensor->fmt.width = 800;
+	sensor->fmt.height = 600;
+	sensor->fmt.field = V4L2_FIELD_NONE;
+	sensor->fmt.colorspace = V4L2_COLORSPACE_SRGB;
+
+	sensor->frame_interval.denominator = ov2680_framerates[OV2680_30_FPS];
+	sensor->frame_interval.numerator = 1;
+
+	sensor->current_fps = OV2680_30_FPS;
+	init_mode = &ov2680_mode_data[OV2680_30_FPS][OV2680_MODE_QUXGA_800_600];
+
+	sensor->current_mode = init_mode;
+
+	sensor->mode_pending_changes = true;
+
+	return 0;
+}
+
+static int ov2680_v4l2_init(struct ov2680_dev *sensor)
+{
+	const struct v4l2_ctrl_ops *ops = &ov2680_ctrl_ops;
+	struct ov2680_ctrls *ctrls = &sensor->ctrls;
+	struct v4l2_ctrl_handler *hdl = &ctrls->handler;
+	int ret = 0;
+
+	v4l2_i2c_subdev_init(&sensor->sd, sensor->i2c_client,
+			     &ov2680_subdev_ops);
+
+	sensor->sd.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
+	sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
+	sensor->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
+
+	ret = media_entity_pads_init(&sensor->sd.entity, 1, &sensor->pad);
+	if (ret < 0)
+		return ret;
+
+	v4l2_ctrl_handler_init(hdl, 32);
+
+	hdl->lock = &sensor->lock;
+
+	ctrls->vflip = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_VFLIP, 0, 1, 1, 0);
+	ctrls->hflip = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HFLIP, 0, 1, 1, 0);
+
+	ctrls->test_pattern = v4l2_ctrl_new_std_menu_items(hdl,
+					&ov2680_ctrl_ops,
+					V4L2_CID_TEST_PATTERN,
+					ARRAY_SIZE(test_pattern_menu) - 1,
+					0, 0, test_pattern_menu);
+
+	ctrls->auto_exp = v4l2_ctrl_new_std_menu(hdl, ops,
+						 V4L2_CID_EXPOSURE_AUTO,
+						 V4L2_EXPOSURE_MANUAL, 0,
+						 V4L2_EXPOSURE_AUTO);
+
+	ctrls->exposure = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE,
+					    0, 32767, 1, 0);
+
+	ctrls->auto_gain = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_AUTOGAIN,
+					     0, 1, 1, 1);
+	ctrls->gain = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_GAIN, 0, 2047, 1, 0);
+
+	ctrls->gain->flags |= V4L2_CTRL_FLAG_VOLATILE;
+	ctrls->exposure->flags |= V4L2_CTRL_FLAG_VOLATILE;
+
+	v4l2_ctrl_auto_cluster(2, &ctrls->auto_gain, 1, true);
+	v4l2_ctrl_auto_cluster(2, &ctrls->auto_exp, 1, true);
+
+	sensor->sd.ctrl_handler = hdl;
+
+	ret = v4l2_async_register_subdev(&sensor->sd);
+	if (ret < 0) {
+		media_entity_cleanup(&sensor->sd.entity);
+		v4l2_ctrl_handler_free(hdl);
+	}
+
+	return ret;
+}
+
+static int ov2680_check_id(struct ov2680_dev *sensor)
+{
+	struct device *dev = ov2680_to_dev(sensor);
+	u8 chip_id_high;
+	u8 chip_id_low;
+	int ret;
+
+	ov2680_reset(sensor);
+
+	ret = ov2680_read_reg(sensor, OV2680_REG_CHIP_ID_HIGH, &chip_id_high);
+	if (ret < 0) {
+		dev_err(dev, "failed to read chip id high\n");
+		return -ENODEV;
+	}
+
+	ret = ov2680_read_reg(sensor, OV2680_REG_CHIP_ID_LOW, &chip_id_low);
+	if (ret < 0) {
+		dev_err(dev, "failed to read chip id low\n");
+		return -ENODEV;
+	}
+
+	if (chip_id_high != OV2680_CHIP_ID_HIGH ||
+	    chip_id_low != OV2680_CHIP_ID_LOW) {
+		dev_err(dev, "chip id: 0x%02x%02x does not match expected: 0x%02x%02x\n",
+			chip_id_high, chip_id_low, OV2680_CHIP_ID_HIGH,
+			OV2680_CHIP_ID_LOW);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int ov2860_parse_dt(struct ov2680_dev *sensor)
+{
+	struct device *dev = ov2680_to_dev(sensor);
+	int ret;
+
+	sensor->pwdn_gpio = devm_gpiod_get_optional(dev, "powerdown",
+						    GPIOD_OUT_HIGH);
+	ret = PTR_ERR_OR_ZERO(sensor->pwdn_gpio);
+	if (ret < 0) {
+		dev_dbg(dev, "error while getting powerdown gpio: %d\n", ret);
+		return ret;
+	}
+
+	sensor->xvclk = devm_clk_get(dev, "xvclk");
+	if (IS_ERR(sensor->xvclk)) {
+		dev_err(dev, "xvclk clock missing or invalid\n");
+		return PTR_ERR(sensor->xvclk);
+	}
+
+	sensor->xvclk_freq = clk_get_rate(sensor->xvclk);
+	if (sensor->xvclk_freq < OV2680_XVCLK_MIN ||
+	    sensor->xvclk_freq > OV2680_XVCLK_MAX) {
+		dev_err(dev, "xvclk frequency out of range: %d Hz\n",
+			sensor->xvclk_freq);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int ov2680_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct ov2680_dev *sensor;
+	int ret;
+
+	sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL);
+	if (!sensor)
+		return -ENOMEM;
+
+	sensor->i2c_client = client;
+
+	ret = ov2860_parse_dt(sensor);
+	if (ret < 0)
+		return -EINVAL;
+
+	ret = ov2680_check_id(sensor);
+	if (ret < 0)
+		return ret;
+
+	ret = ov2680_mode_init(sensor);
+	if (ret < 0)
+		return ret;
+
+	mutex_init(&sensor->lock);
+
+	ret = ov2680_v4l2_init(sensor);
+	if (ret < 0)
+		goto lock_destroy;
+
+	dev_info(dev, "ov2680 init correctly\n");
+
+	return 0;
+
+lock_destroy:
+	mutex_destroy(&sensor->lock);
+
+	return ret;
+}
+
+static int ov2680_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+
+	v4l2_async_unregister_subdev(&sensor->sd);
+	mutex_destroy(&sensor->lock);
+	media_entity_cleanup(&sensor->sd.entity);
+	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
+
+	return 0;
+}
+
+static int __maybe_unused ov2680_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+
+	if (sensor->is_streaming)
+		ov2680_stream_disable(sensor);
+
+	return 0;
+}
+
+static int __maybe_unused ov2680_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct ov2680_dev *sensor = to_ov2680_dev(sd);
+	int ret;
+
+	if (sensor->is_streaming) {
+		ret = ov2680_stream_enable(sensor);
+		if (ret < 0)
+			goto stream_disable;
+	}
+
+	return 0;
+
+stream_disable:
+	ov2680_stream_disable(sensor);
+	sensor->is_streaming = false;
+
+	return ret;
+}
+
+static const struct dev_pm_ops ov2680_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(ov2680_suspend, ov2680_resume)
+};
+
+static const struct i2c_device_id ov2680_id[] = {
+	{"ov2680", 0},
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, ov2680_id);
+
+static const struct of_device_id ov2680_dt_ids[] = {
+	{ .compatible = "ovti,ov2680" },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ov2680_dt_ids);
+
+static struct i2c_driver ov2680_i2c_driver = {
+	.driver = {
+		.name  = "ovti,ov2680",
+		.of_match_table	= ov2680_dt_ids,
+	},
+	.id_table = ov2680_id,
+	.probe    = ov2680_probe,
+	.remove   = ov2680_remove,
+};
+module_i2c_driver(ov2680_i2c_driver);
+
+MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");
+MODULE_DESCRIPTION("OV2680 CMOS Image Sensor driver");
+MODULE_LICENSE("GPL v2");
-- 
2.16.2