// SPDX-License-Identifier: GPL-2.0
/*
 * A V4L2 driver for Sony IMX219 cameras.
 * Copyright (C) 2019, Raspberry Pi (Trading) Ltd
 *
 * Based on Sony imx258 camera driver
 * Copyright (C) 2018 Intel Corporation
 *
 * DT / fwnode changes, and regulator / GPIO control taken from imx214 driver
 * Copyright 2018 Qtechnology A/S
 *
 * Flip handling taken from the Sony IMX319 driver.
 * Copyright (C) 2018 Intel Corporation
 *
 */

#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/clkdev.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 <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
#include <media/v4l2-event.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-mediabus.h>
#include <asm/unaligned.h>

#define IMX219_REG_VALUE_08BIT		1
#define IMX219_REG_VALUE_16BIT		2

#define IMX219_REG_MODE_SELECT		0x0100
#define IMX219_MODE_STANDBY		0x00
#define IMX219_MODE_STREAMING		0x01

/* Chip ID */
#define IMX219_REG_CHIP_ID		0x0000
#define IMX219_CHIP_ID			0x0219

/* External clock frequency is 24.0M */
#define IMX219_XCLK_FREQ		24000000

/* Pixel rate is fixed at 182.4M for all the modes */
#define IMX219_PIXEL_RATE		182400000

#define IMX219_DEFAULT_LINK_FREQ	456000000

/* V_TIMING internal */
#define IMX219_REG_VTS			0x0160
#define IMX219_VTS_15FPS		0x0dc6
#define IMX219_VTS_30FPS_1080P		0x06e3
#define IMX219_VTS_30FPS_BINNED		0x06e3
#define IMX219_VTS_MAX			0xffff

#define IMX219_VBLANK_MIN		4

/*Frame Length Line*/
#define IMX219_FLL_MIN			0x08a6
#define IMX219_FLL_MAX			0xffff
#define IMX219_FLL_STEP			1
#define IMX219_FLL_DEFAULT		0x0c98

/* HBLANK control - read only */
#define IMX219_PPL_DEFAULT		3448

/* Exposure control */
#define IMX219_REG_EXPOSURE		0x015a
#define IMX219_EXPOSURE_MIN		4
#define IMX219_EXPOSURE_STEP		1
#define IMX219_EXPOSURE_DEFAULT		0x640
#define IMX219_EXPOSURE_MAX		65535

/* Analog gain control */
#define IMX219_REG_ANALOG_GAIN		0x0157
#define IMX219_ANA_GAIN_MIN		0
#define IMX219_ANA_GAIN_MAX		232
#define IMX219_ANA_GAIN_STEP		1
#define IMX219_ANA_GAIN_DEFAULT		0x0

/* Digital gain control */
#define IMX219_REG_DIGITAL_GAIN		0x0158
#define IMX219_DGTL_GAIN_MIN		0x0100
#define IMX219_DGTL_GAIN_MAX		0x0fff
#define IMX219_DGTL_GAIN_DEFAULT	0x0100
#define IMX219_DGTL_GAIN_STEP		1

#define IMX219_REG_ORIENTATION		0x0172

/* Test Pattern Control */
#define IMX219_REG_TEST_PATTERN		0x0600
#define IMX219_TEST_PATTERN_DISABLE	0
#define IMX219_TEST_PATTERN_SOLID_COLOR	1
#define IMX219_TEST_PATTERN_COLOR_BARS	2
#define IMX219_TEST_PATTERN_GREY_COLOR	3
#define IMX219_TEST_PATTERN_PN9		4

/* Test pattern colour components */
#define IMX219_REG_TESTP_RED		0x0602
#define IMX219_REG_TESTP_GREENR		0x0604
#define IMX219_REG_TESTP_BLUE		0x0606
#define IMX219_REG_TESTP_GREENB		0x0608
#define IMX219_TESTP_COLOUR_MIN		0
#define IMX219_TESTP_COLOUR_MAX		0x03ff
#define IMX219_TESTP_COLOUR_STEP	1
#define IMX219_TESTP_RED_DEFAULT	IMX219_TESTP_COLOUR_MAX
#define IMX219_TESTP_GREENR_DEFAULT	0
#define IMX219_TESTP_BLUE_DEFAULT	0
#define IMX219_TESTP_GREENB_DEFAULT	0

struct imx219_reg {
	u16 address;
	u8 val;
};

struct imx219_reg_list {
	unsigned int num_of_regs;
	const struct imx219_reg *regs;
};

/* Mode : resolution and related config&values */
struct imx219_mode {
	/* Frame width */
	unsigned int width;
	/* Frame height */
	unsigned int height;

	/* V-timing */
	unsigned int vts_def;

	/* Default register values */
	struct imx219_reg_list reg_list;
};

/*
 * Register sets lifted off the i2C interface from the Raspberry Pi firmware
 * driver.
 * 3280x2464 = mode 2, 1920x1080 = mode 1, and 1640x1232 = mode 4.
 */
static const struct imx219_reg mode_3280x2464_regs[] = {
	{0x0100, 0x00},
	{0x30eb, 0x0c},
	{0x30eb, 0x05},
	{0x300a, 0xff},
	{0x300b, 0xff},
	{0x30eb, 0x05},
	{0x30eb, 0x09},
	{0x0114, 0x01},
	{0x0128, 0x00},
	{0x012a, 0x18},
	{0x012b, 0x00},
	{0x0164, 0x00},
	{0x0165, 0x00},
	{0x0166, 0x0c},
	{0x0167, 0xcf},
	{0x0168, 0x00},
	{0x0169, 0x00},
	{0x016a, 0x09},
	{0x016b, 0x9f},
	{0x016c, 0x0c},
	{0x016d, 0xd0},
	{0x016e, 0x09},
	{0x016f, 0xa0},
	{0x0170, 0x01},
	{0x0171, 0x01},
	{0x0174, 0x00},
	{0x0175, 0x00},
	{0x018c, 0x0a},
	{0x018d, 0x0a},
	{0x0301, 0x05},
	{0x0303, 0x01},
	{0x0304, 0x03},
	{0x0305, 0x03},
	{0x0306, 0x00},
	{0x0307, 0x39},
	{0x0309, 0x0a},
	{0x030b, 0x01},
	{0x030c, 0x00},
	{0x030d, 0x72},
	{0x0624, 0x0c},
	{0x0625, 0xd0},
	{0x0626, 0x09},
	{0x0627, 0xa0},
	{0x455e, 0x00},
	{0x471e, 0x4b},
	{0x4767, 0x0f},
	{0x4750, 0x14},
	{0x4540, 0x00},
	{0x47b4, 0x14},
	{0x4713, 0x30},
	{0x478b, 0x10},
	{0x478f, 0x10},
	{0x4793, 0x10},
	{0x4797, 0x0e},
	{0x479b, 0x0e},
	{0x0162, 0x0d},
	{0x0163, 0x78},
};

static const struct imx219_reg mode_1920_1080_regs[] = {
	{0x0100, 0x00},
	{0x30eb, 0x05},
	{0x30eb, 0x0c},
	{0x300a, 0xff},
	{0x300b, 0xff},
	{0x30eb, 0x05},
	{0x30eb, 0x09},
	{0x0114, 0x01},
	{0x0128, 0x00},
	{0x012a, 0x18},
	{0x012b, 0x00},
	{0x0162, 0x0d},
	{0x0163, 0x78},
	{0x0164, 0x02},
	{0x0165, 0xa8},
	{0x0166, 0x0a},
	{0x0167, 0x27},
	{0x0168, 0x02},
	{0x0169, 0xb4},
	{0x016a, 0x06},
	{0x016b, 0xeb},
	{0x016c, 0x07},
	{0x016d, 0x80},
	{0x016e, 0x04},
	{0x016f, 0x38},
	{0x0170, 0x01},
	{0x0171, 0x01},
	{0x0174, 0x00},
	{0x0175, 0x00},
	{0x018c, 0x0a},
	{0x018d, 0x0a},
	{0x0301, 0x05},
	{0x0303, 0x01},
	{0x0304, 0x03},
	{0x0305, 0x03},
	{0x0306, 0x00},
	{0x0307, 0x39},
	{0x0309, 0x0a},
	{0x030b, 0x01},
	{0x030c, 0x00},
	{0x030d, 0x72},
	{0x0624, 0x07},
	{0x0625, 0x80},
	{0x0626, 0x04},
	{0x0627, 0x38},
	{0x455e, 0x00},
	{0x471e, 0x4b},
	{0x4767, 0x0f},
	{0x4750, 0x14},
	{0x4540, 0x00},
	{0x47b4, 0x14},
	{0x4713, 0x30},
	{0x478b, 0x10},
	{0x478f, 0x10},
	{0x4793, 0x10},
	{0x4797, 0x0e},
	{0x479b, 0x0e},
	{0x0162, 0x0d},
	{0x0163, 0x78},
};

static const struct imx219_reg mode_1640_1232_regs[] = {
	{0x0100, 0x00},
	{0x30eb, 0x0c},
	{0x30eb, 0x05},
	{0x300a, 0xff},
	{0x300b, 0xff},
	{0x30eb, 0x05},
	{0x30eb, 0x09},
	{0x0114, 0x01},
	{0x0128, 0x00},
	{0x012a, 0x18},
	{0x012b, 0x00},
	{0x0164, 0x00},
	{0x0165, 0x00},
	{0x0166, 0x0c},
	{0x0167, 0xcf},
	{0x0168, 0x00},
	{0x0169, 0x00},
	{0x016a, 0x09},
	{0x016b, 0x9f},
	{0x016c, 0x06},
	{0x016d, 0x68},
	{0x016e, 0x04},
	{0x016f, 0xd0},
	{0x0170, 0x01},
	{0x0171, 0x01},
	{0x0174, 0x01},
	{0x0175, 0x01},
	{0x018c, 0x0a},
	{0x018d, 0x0a},
	{0x0301, 0x05},
	{0x0303, 0x01},
	{0x0304, 0x03},
	{0x0305, 0x03},
	{0x0306, 0x00},
	{0x0307, 0x39},
	{0x0309, 0x0a},
	{0x030b, 0x01},
	{0x030c, 0x00},
	{0x030d, 0x72},
	{0x0624, 0x06},
	{0x0625, 0x68},
	{0x0626, 0x04},
	{0x0627, 0xd0},
	{0x455e, 0x00},
	{0x471e, 0x4b},
	{0x4767, 0x0f},
	{0x4750, 0x14},
	{0x4540, 0x00},
	{0x47b4, 0x14},
	{0x4713, 0x30},
	{0x478b, 0x10},
	{0x478f, 0x10},
	{0x4793, 0x10},
	{0x4797, 0x0e},
	{0x479b, 0x0e},
	{0x0162, 0x0d},
	{0x0163, 0x78},
};

static const char * const imx219_test_pattern_menu[] = {
	"Disabled",
	"Color Bars",
	"Solid Color",
	"Grey Color Bars",
	"PN9"
};

static const int imx219_test_pattern_val[] = {
	IMX219_TEST_PATTERN_DISABLE,
	IMX219_TEST_PATTERN_COLOR_BARS,
	IMX219_TEST_PATTERN_SOLID_COLOR,
	IMX219_TEST_PATTERN_GREY_COLOR,
	IMX219_TEST_PATTERN_PN9,
};

/* regulator supplies */
static const char * const imx219_supply_name[] = {
	/* Supplies can be enabled in any order */
	"VANA",  /* Analog (2.8V) supply */
	"VDIG",  /* Digital Core (1.8V) supply */
	"VDDL",  /* IF (1.2V) supply */
};

#define IMX219_NUM_SUPPLIES ARRAY_SIZE(imx219_supply_name)

/*
 * Initialisation delay between XCLR low->high and the moment when the sensor
 * can start capture (i.e. can leave software stanby) must be not less than:
 *   t4 + max(t5, t6 + <time to initialize the sensor register over I2C>)
 * where
 *   t4 is fixed, and is max 200uS,
 *   t5 is fixed, and is 6000uS,
 *   t6 depends on the sensor external clock, and is max 32000 clock periods.
 * As per sensor datasheet, the external clock must be from 6MHz to 27MHz.
 * So for any acceptable external clock t6 is always within the range of
 * 1185 to 5333 uS, and is always less than t5.
 * For this reason this is always safe to wait (t4 + t5) = 6200 uS, then
 * initialize the sensor over I2C, and then exit the software standby.
 *
 * This start-up time can be optimized a bit more, if we start the writes
 * over I2C after (t4+t6), but before (t4+t5) expires. But then sensor
 * initialization over I2C may complete before (t4+t5) expires, and we must
 * ensure that capture is not started before (t4+t5).
 *
 * This delay doesn't account for the power supply startup time. If needed,
 * this should be taken care of via the regulator framework. E.g. in the
 * case of DT for regulator-fixed one should define the startup-delay-us
 * property.
 */
#define IMX219_XCLR_MIN_DELAY_US	6200
#define IMX219_XCLR_DELAY_RANGE_US	1000

/* Mode configs */
static const struct imx219_mode supported_modes[] = {
	{
		/* 8MPix 15fps mode */
		.width = 3280,
		.height = 2464,
		.vts_def = IMX219_VTS_15FPS,
		.reg_list = {
			.num_of_regs = ARRAY_SIZE(mode_3280x2464_regs),
			.regs = mode_3280x2464_regs,
		},
	},
	{
		/* 1080P 30fps cropped */
		.width = 1920,
		.height = 1080,
		.vts_def = IMX219_VTS_30FPS_1080P,
		.reg_list = {
			.num_of_regs = ARRAY_SIZE(mode_1920_1080_regs),
			.regs = mode_1920_1080_regs,
		},
	},
	{
		/* 2x2 binned 30fps mode */
		.width = 1640,
		.height = 1232,
		.vts_def = IMX219_VTS_30FPS_BINNED,
		.reg_list = {
			.num_of_regs = ARRAY_SIZE(mode_1640_1232_regs),
			.regs = mode_1640_1232_regs,
		},
	},
};

struct imx219 {
	struct v4l2_subdev sd;
	struct media_pad pad;

	struct clk *xclk; /* system clock to IMX219 */
	u32 xclk_freq;

	struct gpio_desc *reset_gpio;
	struct regulator_bulk_data supplies[IMX219_NUM_SUPPLIES];

	struct v4l2_ctrl_handler ctrl_handler;
	/* V4L2 Controls */
	struct v4l2_ctrl *pixel_rate;
	struct v4l2_ctrl *exposure;
	struct v4l2_ctrl *vflip;
	struct v4l2_ctrl *hflip;
	struct v4l2_ctrl *vblank;
	struct v4l2_ctrl *hblank;

	/* Current mode */
	const struct imx219_mode *mode;

	/*
	 * Mutex for serialized access:
	 * Protect sensor module set pad format and start/stop streaming safely.
	 */
	struct mutex mutex;

	/* Streaming on/off */
	bool streaming;
};

static inline struct imx219 *to_imx219(struct v4l2_subdev *_sd)
{
	return container_of(_sd, struct imx219, sd);
}

/* Read registers up to 2 at a time */
static int imx219_read_reg(struct imx219 *imx219, u16 reg, u32 len, u32 *val)
{
	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
	struct i2c_msg msgs[2];
	u8 addr_buf[2] = { reg >> 8, reg & 0xff };
	u8 data_buf[4] = { 0, };
	int ret;

	if (len > 4)
		return -EINVAL;

	/* Write register address */
	msgs[0].addr = client->addr;
	msgs[0].flags = 0;
	msgs[0].len = ARRAY_SIZE(addr_buf);
	msgs[0].buf = addr_buf;

	/* Read data from register */
	msgs[1].addr = client->addr;
	msgs[1].flags = I2C_M_RD;
	msgs[1].len = len;
	msgs[1].buf = &data_buf[4 - len];

	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	if (ret != ARRAY_SIZE(msgs))
		return -EIO;

	*val = get_unaligned_be32(data_buf);

	return 0;
}

/* Write registers up to 2 at a time */
static int imx219_write_reg(struct imx219 *imx219, u16 reg, u32 len, u32 val)
{
	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
	u8 buf[6];

	if (len > 4)
		return -EINVAL;

	put_unaligned_be16(reg, buf);
	put_unaligned_be32(val << (8 * (4 - len)), buf + 2);
	if (i2c_master_send(client, buf, len + 2) != len + 2)
		return -EIO;

	return 0;
}

/* Write a list of registers */
static int imx219_write_regs(struct imx219 *imx219,
			     const struct imx219_reg *regs, u32 len)
{
	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
	unsigned int i;
	int ret;

	for (i = 0; i < len; i++) {
		ret = imx219_write_reg(imx219, regs[i].address, 1, regs[i].val);
		if (ret) {
			dev_err_ratelimited(&client->dev,
					    "Failed to write reg 0x%4.4x. error = %d\n",
					    regs[i].address, ret);

			return ret;
		}
	}

	return 0;
}

/* Get bayer order based on flip setting. */
static u32 imx219_get_format_code(struct imx219 *imx219)
{
	/*
	 * Only one bayer order is supported.
	 * It depends on the flip settings.
	 */
	static const u32 codes[2][2] = {
		{ MEDIA_BUS_FMT_SRGGB10_1X10, MEDIA_BUS_FMT_SGRBG10_1X10, },
		{ MEDIA_BUS_FMT_SGBRG10_1X10, MEDIA_BUS_FMT_SBGGR10_1X10, },
	};

	lockdep_assert_held(&imx219->mutex);
	return codes[imx219->vflip->val][imx219->hflip->val];
}

static int imx219_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
	struct imx219 *imx219 = to_imx219(sd);
	struct v4l2_mbus_framefmt *try_fmt =
		v4l2_subdev_get_try_format(sd, fh->pad, 0);

	mutex_lock(&imx219->mutex);

	/* Initialize try_fmt */
	try_fmt->width = supported_modes[0].width;
	try_fmt->height = supported_modes[0].height;
	try_fmt->code = imx219_get_format_code(imx219);
	try_fmt->field = V4L2_FIELD_NONE;

	mutex_unlock(&imx219->mutex);

	return 0;
}

static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
{
	struct imx219 *imx219 =
		container_of(ctrl->handler, struct imx219, ctrl_handler);
	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
	int ret;

	if (ctrl->id == V4L2_CID_VBLANK) {
		int exposure_max, exposure_def;

		/* Update max exposure while meeting expected vblanking */
		exposure_max = imx219->mode->height + ctrl->val - 4;
		exposure_def = (exposure_max < IMX219_EXPOSURE_DEFAULT) ?
			exposure_max : IMX219_EXPOSURE_DEFAULT;
		__v4l2_ctrl_modify_range(imx219->exposure,
					 imx219->exposure->minimum,
					 exposure_max, imx219->exposure->step,
					 exposure_def);
	}

	/*
	 * Applying V4L2 control value only happens
	 * when power is up for streaming
	 */
	if (pm_runtime_get_if_in_use(&client->dev) == 0)
		return 0;

	switch (ctrl->id) {
	case V4L2_CID_ANALOGUE_GAIN:
		ret = imx219_write_reg(imx219, IMX219_REG_ANALOG_GAIN,
				       IMX219_REG_VALUE_08BIT, ctrl->val);
		break;
	case V4L2_CID_EXPOSURE:
		ret = imx219_write_reg(imx219, IMX219_REG_EXPOSURE,
				       IMX219_REG_VALUE_16BIT, ctrl->val);
		break;
	case V4L2_CID_DIGITAL_GAIN:
		ret = imx219_write_reg(imx219, IMX219_REG_DIGITAL_GAIN,
				       IMX219_REG_VALUE_16BIT, ctrl->val);
		break;
	case V4L2_CID_TEST_PATTERN:
		ret = imx219_write_reg(imx219, IMX219_REG_TEST_PATTERN,
				       IMX219_REG_VALUE_16BIT,
				       imx219_test_pattern_val[ctrl->val]);
		break;
	case V4L2_CID_HFLIP:
	case V4L2_CID_VFLIP:
		ret = imx219_write_reg(imx219, IMX219_REG_ORIENTATION, 1,
				       imx219->hflip->val |
				       imx219->vflip->val << 1);
		break;
	case V4L2_CID_VBLANK:
		ret = imx219_write_reg(imx219, IMX219_REG_VTS,
				       IMX219_REG_VALUE_16BIT,
				       imx219->mode->height + ctrl->val);
		break;
	case V4L2_CID_TEST_PATTERN_RED:
		ret = imx219_write_reg(imx219, IMX219_REG_TESTP_RED,
				       IMX219_REG_VALUE_16BIT, ctrl->val);
		break;
	case V4L2_CID_TEST_PATTERN_GREENR:
		ret = imx219_write_reg(imx219, IMX219_REG_TESTP_GREENR,
				       IMX219_REG_VALUE_16BIT, ctrl->val);
		break;
	case V4L2_CID_TEST_PATTERN_BLUE:
		ret = imx219_write_reg(imx219, IMX219_REG_TESTP_BLUE,
				       IMX219_REG_VALUE_16BIT, ctrl->val);
		break;
	case V4L2_CID_TEST_PATTERN_GREENB:
		ret = imx219_write_reg(imx219, IMX219_REG_TESTP_GREENB,
				       IMX219_REG_VALUE_16BIT, ctrl->val);
		break;
	default:
		dev_info(&client->dev,
			 "ctrl(id:0x%x,val:0x%x) is not handled\n",
			 ctrl->id, ctrl->val);
		ret = -EINVAL;
		break;
	}

	pm_runtime_put(&client->dev);

	return ret;
}

static const struct v4l2_ctrl_ops imx219_ctrl_ops = {
	.s_ctrl = imx219_set_ctrl,
};

static int imx219_enum_mbus_code(struct v4l2_subdev *sd,
				 struct v4l2_subdev_pad_config *cfg,
				 struct v4l2_subdev_mbus_code_enum *code)
{
	struct imx219 *imx219 = to_imx219(sd);

	/*
	 * Only one bayer order is supported (though it depends on the flip
	 * settings)
	 */
	if (code->index > 0)
		return -EINVAL;

	code->code = imx219_get_format_code(imx219);

	return 0;
}

static int imx219_enum_frame_size(struct v4l2_subdev *sd,
				  struct v4l2_subdev_pad_config *cfg,
				  struct v4l2_subdev_frame_size_enum *fse)
{
	struct imx219 *imx219 = to_imx219(sd);

	if (fse->index >= ARRAY_SIZE(supported_modes))
		return -EINVAL;

	if (fse->code != imx219_get_format_code(imx219))
		return -EINVAL;

	fse->min_width = supported_modes[fse->index].width;
	fse->max_width = fse->min_width;
	fse->min_height = supported_modes[fse->index].height;
	fse->max_height = fse->min_height;

	return 0;
}

static void imx219_reset_colorspace(struct v4l2_mbus_framefmt *fmt)
{
	fmt->colorspace = V4L2_COLORSPACE_SRGB;
	fmt->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(fmt->colorspace);
	fmt->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true,
							  fmt->colorspace,
							  fmt->ycbcr_enc);
	fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt->colorspace);
}

static void imx219_update_pad_format(struct imx219 *imx219,
				     const struct imx219_mode *mode,
				     struct v4l2_subdev_format *fmt)
{
	fmt->format.width = mode->width;
	fmt->format.height = mode->height;
	fmt->format.code = imx219_get_format_code(imx219);
	fmt->format.field = V4L2_FIELD_NONE;

	imx219_reset_colorspace(&fmt->format);
}

static int __imx219_get_pad_format(struct imx219 *imx219,
				   struct v4l2_subdev_pad_config *cfg,
				   struct v4l2_subdev_format *fmt)
{
	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
		struct v4l2_mbus_framefmt *try_fmt =
			v4l2_subdev_get_try_format(&imx219->sd, cfg, fmt->pad);
		/* update the code which could change due to vflip or hflip: */
		try_fmt->code = imx219_get_format_code(imx219);
		fmt->format = *try_fmt;
	} else {
		imx219_update_pad_format(imx219, imx219->mode, fmt);
	}

	return 0;
}

static int imx219_get_pad_format(struct v4l2_subdev *sd,
				 struct v4l2_subdev_pad_config *cfg,
				 struct v4l2_subdev_format *fmt)
{
	struct imx219 *imx219 = to_imx219(sd);
	int ret;

	mutex_lock(&imx219->mutex);
	ret = __imx219_get_pad_format(imx219, cfg, fmt);
	mutex_unlock(&imx219->mutex);

	return ret;
}

static int imx219_set_pad_format(struct v4l2_subdev *sd,
				 struct v4l2_subdev_pad_config *cfg,
				 struct v4l2_subdev_format *fmt)
{
	struct imx219 *imx219 = to_imx219(sd);
	const struct imx219_mode *mode;
	struct v4l2_mbus_framefmt *framefmt;
	int exposure_max, exposure_def, hblank;

	mutex_lock(&imx219->mutex);

	/* Bayer order varies with flips */
	fmt->format.code = imx219_get_format_code(imx219);

	mode = v4l2_find_nearest_size(supported_modes,
				      ARRAY_SIZE(supported_modes),
				      width, height,
				      fmt->format.width, fmt->format.height);
	imx219_update_pad_format(imx219, mode, fmt);
	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
		framefmt = v4l2_subdev_get_try_format(sd, cfg, fmt->pad);
		*framefmt = fmt->format;
	} else if (imx219->mode != mode) {
		imx219->mode = mode;
		/* Update limits and set FPS to default */
		__v4l2_ctrl_modify_range(imx219->vblank, IMX219_VBLANK_MIN,
					 IMX219_VTS_MAX - mode->height, 1,
					 mode->vts_def - mode->height);
		__v4l2_ctrl_s_ctrl(imx219->vblank,
				   mode->vts_def - mode->height);
		/* Update max exposure while meeting expected vblanking */
		exposure_max = mode->vts_def - 4;
		exposure_def = (exposure_max < IMX219_EXPOSURE_DEFAULT) ?
			exposure_max : IMX219_EXPOSURE_DEFAULT;
		__v4l2_ctrl_modify_range(imx219->exposure,
					 imx219->exposure->minimum,
					 exposure_max, imx219->exposure->step,
					 exposure_def);
		/*
		 * Currently PPL is fixed to IMX219_PPL_DEFAULT, so hblank
		 * depends on mode->width only, and is not changeble in any
		 * way other than changing the mode.
		 */
		hblank = IMX219_PPL_DEFAULT - mode->width;
		__v4l2_ctrl_modify_range(imx219->hblank, hblank, hblank, 1,
					 hblank);
	}

	mutex_unlock(&imx219->mutex);

	return 0;
}

static int imx219_start_streaming(struct imx219 *imx219)
{
	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
	const struct imx219_reg_list *reg_list;
	int ret;

	/* Apply default values of current mode */
	reg_list = &imx219->mode->reg_list;
	ret = imx219_write_regs(imx219, reg_list->regs, reg_list->num_of_regs);
	if (ret) {
		dev_err(&client->dev, "%s failed to set mode\n", __func__);
		return ret;
	}

	/* Apply customized values from user */
	ret =  __v4l2_ctrl_handler_setup(imx219->sd.ctrl_handler);
	if (ret)
		return ret;

	/* set stream on register */
	return imx219_write_reg(imx219, IMX219_REG_MODE_SELECT,
				IMX219_REG_VALUE_08BIT, IMX219_MODE_STREAMING);
}

static void imx219_stop_streaming(struct imx219 *imx219)
{
	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
	int ret;

	/* set stream off register */
	ret = imx219_write_reg(imx219, IMX219_REG_MODE_SELECT,
			       IMX219_REG_VALUE_08BIT, IMX219_MODE_STANDBY);
	if (ret)
		dev_err(&client->dev, "%s failed to set stream\n", __func__);
}

static int imx219_set_stream(struct v4l2_subdev *sd, int enable)
{
	struct imx219 *imx219 = to_imx219(sd);
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	int ret = 0;

	mutex_lock(&imx219->mutex);
	if (imx219->streaming == enable) {
		mutex_unlock(&imx219->mutex);
		return 0;
	}

	if (enable) {
		ret = pm_runtime_get_sync(&client->dev);
		if (ret < 0) {
			pm_runtime_put_noidle(&client->dev);
			goto err_unlock;
		}

		/*
		 * Apply default & customized values
		 * and then start streaming.
		 */
		ret = imx219_start_streaming(imx219);
		if (ret)
			goto err_rpm_put;
	} else {
		imx219_stop_streaming(imx219);
		pm_runtime_put(&client->dev);
	}

	imx219->streaming = enable;

	/* vflip and hflip cannot change during streaming */
	__v4l2_ctrl_grab(imx219->vflip, enable);
	__v4l2_ctrl_grab(imx219->hflip, enable);

	mutex_unlock(&imx219->mutex);

	return ret;

err_rpm_put:
	pm_runtime_put(&client->dev);
err_unlock:
	mutex_unlock(&imx219->mutex);

	return ret;
}

/* Power/clock management functions */
static int imx219_power_on(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct v4l2_subdev *sd = i2c_get_clientdata(client);
	struct imx219 *imx219 = to_imx219(sd);
	int ret;

	ret = regulator_bulk_enable(IMX219_NUM_SUPPLIES,
				    imx219->supplies);
	if (ret) {
		dev_err(&client->dev, "%s: failed to enable regulators\n",
			__func__);
		return ret;
	}

	ret = clk_prepare_enable(imx219->xclk);
	if (ret) {
		dev_err(&client->dev, "%s: failed to enable clock\n",
			__func__);
		goto reg_off;
	}

	gpiod_set_value_cansleep(imx219->reset_gpio, 1);
	usleep_range(IMX219_XCLR_MIN_DELAY_US,
		     IMX219_XCLR_MIN_DELAY_US + IMX219_XCLR_DELAY_RANGE_US);

	return 0;

reg_off:
	regulator_bulk_disable(IMX219_NUM_SUPPLIES, imx219->supplies);

	return ret;
}

static int imx219_power_off(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct v4l2_subdev *sd = i2c_get_clientdata(client);
	struct imx219 *imx219 = to_imx219(sd);

	gpiod_set_value_cansleep(imx219->reset_gpio, 0);
	regulator_bulk_disable(IMX219_NUM_SUPPLIES, imx219->supplies);
	clk_disable_unprepare(imx219->xclk);

	return 0;
}

static int __maybe_unused imx219_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct v4l2_subdev *sd = i2c_get_clientdata(client);
	struct imx219 *imx219 = to_imx219(sd);

	if (imx219->streaming)
		imx219_stop_streaming(imx219);

	return 0;
}

static int __maybe_unused imx219_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct v4l2_subdev *sd = i2c_get_clientdata(client);
	struct imx219 *imx219 = to_imx219(sd);
	int ret;

	if (imx219->streaming) {
		ret = imx219_start_streaming(imx219);
		if (ret)
			goto error;
	}

	return 0;

error:
	imx219_stop_streaming(imx219);
	imx219->streaming = 0;

	return ret;
}

static int imx219_get_regulators(struct imx219 *imx219)
{
	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
	unsigned int i;

	for (i = 0; i < IMX219_NUM_SUPPLIES; i++)
		imx219->supplies[i].supply = imx219_supply_name[i];

	return devm_regulator_bulk_get(&client->dev,
				       IMX219_NUM_SUPPLIES,
				       imx219->supplies);
}

/* Verify chip ID */
static int imx219_identify_module(struct imx219 *imx219)
{
	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
	int ret;
	u32 val;

	ret = imx219_read_reg(imx219, IMX219_REG_CHIP_ID,
			      IMX219_REG_VALUE_16BIT, &val);
	if (ret) {
		dev_err(&client->dev, "failed to read chip id %x\n",
			IMX219_CHIP_ID);
		return ret;
	}

	if (val != IMX219_CHIP_ID) {
		dev_err(&client->dev, "chip id mismatch: %x!=%x\n",
			IMX219_CHIP_ID, val);
		return -EIO;
	}

	return 0;
}

static const struct v4l2_subdev_core_ops imx219_core_ops = {
	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
};

static const struct v4l2_subdev_video_ops imx219_video_ops = {
	.s_stream = imx219_set_stream,
};

static const struct v4l2_subdev_pad_ops imx219_pad_ops = {
	.enum_mbus_code = imx219_enum_mbus_code,
	.get_fmt = imx219_get_pad_format,
	.set_fmt = imx219_set_pad_format,
	.enum_frame_size = imx219_enum_frame_size,
};

static const struct v4l2_subdev_ops imx219_subdev_ops = {
	.core = &imx219_core_ops,
	.video = &imx219_video_ops,
	.pad = &imx219_pad_ops,
};

static const struct v4l2_subdev_internal_ops imx219_internal_ops = {
	.open = imx219_open,
};

/* Initialize control handlers */
static int imx219_init_controls(struct imx219 *imx219)
{
	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
	struct v4l2_ctrl_handler *ctrl_hdlr;
	unsigned int height = imx219->mode->height;
	int exposure_max, exposure_def, hblank;
	int i, ret;

	ctrl_hdlr = &imx219->ctrl_handler;
	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 9);
	if (ret)
		return ret;

	mutex_init(&imx219->mutex);
	ctrl_hdlr->lock = &imx219->mutex;

	/* By default, PIXEL_RATE is read only */
	imx219->pixel_rate = v4l2_ctrl_new_std(ctrl_hdlr, &imx219_ctrl_ops,
					       V4L2_CID_PIXEL_RATE,
					       IMX219_PIXEL_RATE,
					       IMX219_PIXEL_RATE, 1,
					       IMX219_PIXEL_RATE);

	/* Initial vblank/hblank/exposure parameters based on current mode */
	imx219->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &imx219_ctrl_ops,
					   V4L2_CID_VBLANK, IMX219_VBLANK_MIN,
					   IMX219_VTS_MAX - height, 1,
					   imx219->mode->vts_def - height);
	hblank = IMX219_PPL_DEFAULT - imx219->mode->width;
	imx219->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &imx219_ctrl_ops,
					   V4L2_CID_HBLANK, hblank, hblank,
					   1, hblank);
	if (imx219->hblank)
		imx219->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
	exposure_max = imx219->mode->vts_def - 4;
	exposure_def = (exposure_max < IMX219_EXPOSURE_DEFAULT) ?
		exposure_max : IMX219_EXPOSURE_DEFAULT;
	imx219->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &imx219_ctrl_ops,
					     V4L2_CID_EXPOSURE,
					     IMX219_EXPOSURE_MIN, exposure_max,
					     IMX219_EXPOSURE_STEP,
					     exposure_def);

	v4l2_ctrl_new_std(ctrl_hdlr, &imx219_ctrl_ops, V4L2_CID_ANALOGUE_GAIN,
			  IMX219_ANA_GAIN_MIN, IMX219_ANA_GAIN_MAX,
			  IMX219_ANA_GAIN_STEP, IMX219_ANA_GAIN_DEFAULT);

	v4l2_ctrl_new_std(ctrl_hdlr, &imx219_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
			  IMX219_DGTL_GAIN_MIN, IMX219_DGTL_GAIN_MAX,
			  IMX219_DGTL_GAIN_STEP, IMX219_DGTL_GAIN_DEFAULT);

	imx219->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &imx219_ctrl_ops,
					  V4L2_CID_HFLIP, 0, 1, 1, 0);
	if (imx219->hflip)
		imx219->hflip->flags |= V4L2_CTRL_FLAG_MODIFY_LAYOUT;

	imx219->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &imx219_ctrl_ops,
					  V4L2_CID_VFLIP, 0, 1, 1, 0);
	if (imx219->vflip)
		imx219->vflip->flags |= V4L2_CTRL_FLAG_MODIFY_LAYOUT;

	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &imx219_ctrl_ops,
				     V4L2_CID_TEST_PATTERN,
				     ARRAY_SIZE(imx219_test_pattern_menu) - 1,
				     0, 0, imx219_test_pattern_menu);
	for (i = 0; i < 4; i++) {
		/*
		 * The assumption is that
		 * V4L2_CID_TEST_PATTERN_GREENR == V4L2_CID_TEST_PATTERN_RED + 1
		 * V4L2_CID_TEST_PATTERN_BLUE   == V4L2_CID_TEST_PATTERN_RED + 2
		 * V4L2_CID_TEST_PATTERN_GREENB == V4L2_CID_TEST_PATTERN_RED + 3
		 */
		v4l2_ctrl_new_std(ctrl_hdlr, &imx219_ctrl_ops,
				  V4L2_CID_TEST_PATTERN_RED + i,
				  IMX219_TESTP_COLOUR_MIN,
				  IMX219_TESTP_COLOUR_MAX,
				  IMX219_TESTP_COLOUR_STEP,
				  IMX219_TESTP_COLOUR_MAX);
		/* The "Solid color" pattern is white by default */
	}

	if (ctrl_hdlr->error) {
		ret = ctrl_hdlr->error;
		dev_err(&client->dev, "%s control init failed (%d)\n",
			__func__, ret);
		goto error;
	}

	imx219->sd.ctrl_handler = ctrl_hdlr;

	return 0;

error:
	v4l2_ctrl_handler_free(ctrl_hdlr);
	mutex_destroy(&imx219->mutex);

	return ret;
}

static void imx219_free_controls(struct imx219 *imx219)
{
	v4l2_ctrl_handler_free(imx219->sd.ctrl_handler);
	mutex_destroy(&imx219->mutex);
}

static int imx219_check_hwcfg(struct device *dev)
{
	struct fwnode_handle *endpoint;
	struct v4l2_fwnode_endpoint ep_cfg = {
		.bus_type = V4L2_MBUS_CSI2_DPHY
	};
	int ret = -EINVAL;

	endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(dev), NULL);
	if (!endpoint) {
		dev_err(dev, "endpoint node not found\n");
		return -EINVAL;
	}

	if (v4l2_fwnode_endpoint_alloc_parse(endpoint, &ep_cfg)) {
		dev_err(dev, "could not parse endpoint\n");
		goto error_out;
	}

	/* Check the number of MIPI CSI2 data lanes */
	if (ep_cfg.bus.mipi_csi2.num_data_lanes != 2) {
		dev_err(dev, "only 2 data lanes are currently supported\n");
		goto error_out;
	}

	/* Check the link frequency set in device tree */
	if (!ep_cfg.nr_of_link_frequencies) {
		dev_err(dev, "link-frequency property not found in DT\n");
		goto error_out;
	}

	if (ep_cfg.nr_of_link_frequencies != 1 ||
	    ep_cfg.link_frequencies[0] != IMX219_DEFAULT_LINK_FREQ) {
		dev_err(dev, "Link frequency not supported: %lld\n",
			ep_cfg.link_frequencies[0]);
		goto error_out;
	}

	ret = 0;

error_out:
	v4l2_fwnode_endpoint_free(&ep_cfg);
	fwnode_handle_put(endpoint);

	return ret;
}

static int imx219_probe(struct i2c_client *client)
{
	struct device *dev = &client->dev;
	struct imx219 *imx219;
	int ret;

	imx219 = devm_kzalloc(&client->dev, sizeof(*imx219), GFP_KERNEL);
	if (!imx219)
		return -ENOMEM;

	v4l2_i2c_subdev_init(&imx219->sd, client, &imx219_subdev_ops);

	/* Check the hardware configuration in device tree */
	if (imx219_check_hwcfg(dev))
		return -EINVAL;

	/* Get system clock (xclk) */
	imx219->xclk = devm_clk_get(dev, NULL);
	if (IS_ERR(imx219->xclk)) {
		dev_err(dev, "failed to get xclk\n");
		return PTR_ERR(imx219->xclk);
	}

	imx219->xclk_freq = clk_get_rate(imx219->xclk);
	if (imx219->xclk_freq != IMX219_XCLK_FREQ) {
		dev_err(dev, "xclk frequency not supported: %d Hz\n",
			imx219->xclk_freq);
		return -EINVAL;
	}

	ret = imx219_get_regulators(imx219);
	if (ret) {
		dev_err(dev, "failed to get regulators\n");
		return ret;
	}

	/* Request optional enable pin */
	imx219->reset_gpio = devm_gpiod_get_optional(dev, "reset",
						     GPIOD_OUT_HIGH);

	/*
	 * The sensor must be powered for imx219_identify_module()
	 * to be able to read the CHIP_ID register
	 */
	ret = imx219_power_on(dev);
	if (ret)
		return ret;

	ret = imx219_identify_module(imx219);
	if (ret)
		goto error_power_off;

	/* Set default mode to max resolution */
	imx219->mode = &supported_modes[0];

	ret = imx219_init_controls(imx219);
	if (ret)
		goto error_power_off;

	/* Initialize subdev */
	imx219->sd.internal_ops = &imx219_internal_ops;
	imx219->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
	imx219->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;

	/* Initialize source pad */
	imx219->pad.flags = MEDIA_PAD_FL_SOURCE;

	ret = media_entity_pads_init(&imx219->sd.entity, 1, &imx219->pad);
	if (ret) {
		dev_err(dev, "failed to init entity pads: %d\n", ret);
		goto error_handler_free;
	}

	ret = v4l2_async_register_subdev_sensor_common(&imx219->sd);
	if (ret < 0) {
		dev_err(dev, "failed to register sensor sub-device: %d\n", ret);
		goto error_media_entity;
	}

	/* Enable runtime PM and turn off the device */
	pm_runtime_set_active(dev);
	pm_runtime_enable(dev);
	pm_runtime_idle(dev);

	return 0;

error_media_entity:
	media_entity_cleanup(&imx219->sd.entity);

error_handler_free:
	imx219_free_controls(imx219);

error_power_off:
	imx219_power_off(dev);

	return ret;
}

static int imx219_remove(struct i2c_client *client)
{
	struct v4l2_subdev *sd = i2c_get_clientdata(client);
	struct imx219 *imx219 = to_imx219(sd);

	v4l2_async_unregister_subdev(sd);
	media_entity_cleanup(&sd->entity);
	imx219_free_controls(imx219);

	pm_runtime_disable(&client->dev);
	if (!pm_runtime_status_suspended(&client->dev))
		imx219_power_off(&client->dev);
	pm_runtime_set_suspended(&client->dev);

	return 0;
}

static const struct of_device_id imx219_dt_ids[] = {
	{ .compatible = "sony,imx219" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, imx219_dt_ids);

static const struct dev_pm_ops imx219_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(imx219_suspend, imx219_resume)
	SET_RUNTIME_PM_OPS(imx219_power_off, imx219_power_on, NULL)
};

static struct i2c_driver imx219_i2c_driver = {
	.driver = {
		.name = "imx219",
		.of_match_table	= imx219_dt_ids,
		.pm = &imx219_pm_ops,
	},
	.probe_new = imx219_probe,
	.remove = imx219_remove,
};

module_i2c_driver(imx219_i2c_driver);

MODULE_AUTHOR("Dave Stevenson <dave.stevenson@raspberrypi.com");
MODULE_DESCRIPTION("Sony IMX219 sensor driver");
MODULE_LICENSE("GPL v2");