// SPDX-License-Identifier: GPL-2.0-only
/*
 * TC358746 - Parallel <-> CSI-2 Bridge
 *
 * Copyright 2022 Marco Felsch <kernel@pengutronix.de>
 *
 * Notes:
 *  - Currently only 'Parallel-in -> CSI-out' mode is supported!
 */

#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/phy/phy-mipi-dphy.h>
#include <linux/property.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/units.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-mc.h>

/* 16-bit registers */
#define CHIPID_REG			0x0000
#define		CHIPID			GENMASK(15, 8)

#define SYSCTL_REG			0x0002
#define		SRESET			BIT(0)

#define CONFCTL_REG			0x0004
#define		PDATAF_MASK		GENMASK(9, 8)
#define		PDATAF_MODE0		0
#define		PDATAF_MODE1		1
#define		PDATAF_MODE2		2
#define		PDATAF(val)		FIELD_PREP(PDATAF_MASK, (val))
#define		PPEN			BIT(6)
#define		DATALANE_MASK		GENMASK(1, 0)

#define FIFOCTL_REG			0x0006
#define DATAFMT_REG			0x0008
#define		PDFMT(val)		FIELD_PREP(GENMASK(7, 4), (val))

#define MCLKCTL_REG			0x000c
#define		MCLK_HIGH_MASK		GENMASK(15, 8)
#define		MCLK_LOW_MASK		GENMASK(7, 0)
#define		MCLK_HIGH(val)		FIELD_PREP(MCLK_HIGH_MASK, (val))
#define		MCLK_LOW(val)		FIELD_PREP(MCLK_LOW_MASK, (val))

#define PLLCTL0_REG			0x0016
#define		PLL_PRD_MASK		GENMASK(15, 12)
#define		PLL_PRD(val)		FIELD_PREP(PLL_PRD_MASK, (val))
#define		PLL_FBD_MASK		GENMASK(8, 0)
#define		PLL_FBD(val)		FIELD_PREP(PLL_FBD_MASK, (val))

#define PLLCTL1_REG			0x0018
#define		PLL_FRS_MASK		GENMASK(11, 10)
#define		PLL_FRS(val)		FIELD_PREP(PLL_FRS_MASK, (val))
#define		CKEN			BIT(4)
#define		RESETB			BIT(1)
#define		PLL_EN			BIT(0)

#define CLKCTL_REG			0x0020
#define		MCLKDIV_MASK		GENMASK(3, 2)
#define		MCLKDIV(val)		FIELD_PREP(MCLKDIV_MASK, (val))
#define		MCLKDIV_8		0
#define		MCLKDIV_4		1
#define		MCLKDIV_2		2

#define WORDCNT_REG			0x0022
#define PP_MISC_REG			0x0032
#define		FRMSTOP			BIT(15)
#define		RSTPTR			BIT(14)

/* 32-bit registers */
#define CLW_DPHYCONTTX_REG		0x0100
#define CLW_CNTRL_REG			0x0140
#define D0W_CNTRL_REG			0x0144
#define		LANEDISABLE		BIT(0)

#define STARTCNTRL_REG			0x0204
#define		START			BIT(0)

#define LINEINITCNT_REG			0x0210
#define LPTXTIMECNT_REG			0x0214
#define TCLK_HEADERCNT_REG		0x0218
#define		TCLK_ZEROCNT(val)	FIELD_PREP(GENMASK(15, 8), (val))
#define		TCLK_PREPARECNT(val)	FIELD_PREP(GENMASK(6, 0), (val))

#define TCLK_TRAILCNT_REG		0x021C
#define THS_HEADERCNT_REG		0x0220
#define		THS_ZEROCNT(val)	FIELD_PREP(GENMASK(14, 8), (val))
#define		THS_PREPARECNT(val)	FIELD_PREP(GENMASK(6, 0), (val))

#define TWAKEUP_REG			0x0224
#define TCLK_POSTCNT_REG		0x0228
#define THS_TRAILCNT_REG		0x022C
#define HSTXVREGEN_REG			0x0234
#define TXOPTIONCNTRL_REG		0x0238
#define CSI_CONTROL_REG			0x040C
#define		CSI_MODE		BIT(15)
#define		TXHSMD			BIT(7)
#define		NOL(val)		FIELD_PREP(GENMASK(2, 1), (val))

#define CSI_CONFW_REG			0x0500
#define		MODE(val)		FIELD_PREP(GENMASK(31, 29), (val))
#define		MODE_SET		0x5
#define		ADDRESS(val)		FIELD_PREP(GENMASK(28, 24), (val))
#define		CSI_CONTROL_ADDRESS	0x3
#define		DATA(val)		FIELD_PREP(GENMASK(15, 0), (val))

#define CSI_START_REG			0x0518
#define		STRT			BIT(0)

static const struct v4l2_mbus_framefmt tc358746_def_fmt = {
	.width		= 640,
	.height		= 480,
	.code		= MEDIA_BUS_FMT_UYVY8_2X8,
	.field		= V4L2_FIELD_NONE,
	.colorspace	= V4L2_COLORSPACE_DEFAULT,
	.ycbcr_enc	= V4L2_YCBCR_ENC_DEFAULT,
	.quantization	= V4L2_QUANTIZATION_DEFAULT,
	.xfer_func	= V4L2_XFER_FUNC_DEFAULT,
};

static const char * const tc358746_supplies[] = {
	"vddc", "vddio", "vddmipi"
};

enum {
	TC358746_SINK,
	TC358746_SOURCE,
	TC358746_NR_PADS
};

struct tc358746 {
	struct v4l2_subdev		sd;
	struct media_pad		pads[TC358746_NR_PADS];
	struct v4l2_async_notifier	notifier;
	struct v4l2_fwnode_endpoint	csi_vep;

	struct v4l2_ctrl_handler	ctrl_hdl;

	struct regmap			*regmap;
	struct clk			*refclk;
	struct gpio_desc		*reset_gpio;
	struct regulator_bulk_data	supplies[ARRAY_SIZE(tc358746_supplies)];

	struct clk_hw			mclk_hw;
	unsigned long			mclk_rate;
	u8				mclk_prediv;
	u16				mclk_postdiv;

	unsigned long			pll_rate;
	u8				pll_post_div;
	u16				pll_pre_div;
	u16				pll_mul;

	struct phy_configure_opts_mipi_dphy dphy_cfg;
};

static inline struct tc358746 *to_tc358746(struct v4l2_subdev *sd)
{
	return container_of(sd, struct tc358746, sd);
}

static inline struct tc358746 *clk_hw_to_tc358746(struct clk_hw *hw)
{
	return container_of(hw, struct tc358746, mclk_hw);
}

struct tc358746_format {
	u32		code;
	bool		csi_format;
	unsigned char	bus_width;
	unsigned char	bpp;
	/* Register values */
	u8		pdformat; /* Peripheral Data Format */
	u8		pdataf;   /* Parallel Data Format Option */
};

enum {
	PDFORMAT_RAW8 = 0,
	PDFORMAT_RAW10,
	PDFORMAT_RAW12,
	PDFORMAT_RGB888,
	PDFORMAT_RGB666,
	PDFORMAT_RGB565,
	PDFORMAT_YUV422_8BIT,
	/* RESERVED = 7 */
	PDFORMAT_RAW14 = 8,
	PDFORMAT_YUV422_10BIT,
	PDFORMAT_YUV444,
};

#define TC358746_FORMAT_RAW(_bpp, _code)		\
{							\
	.code = _code,					\
	.bus_width = _bpp,				\
	.bpp = _bpp,					\
	.pdformat = PDFORMAT_RAW##_bpp,			\
	.pdataf = PDATAF_MODE0, /* don't care */	\
}

/* Check tc358746_src_mbus_code() if you add new formats */
static const struct tc358746_format tc358746_formats[] = {
	{
		.code = MEDIA_BUS_FMT_UYVY8_2X8,
		.bus_width = 8,
		.bpp = 16,
		.pdformat = PDFORMAT_YUV422_8BIT,
		.pdataf = PDATAF_MODE0,
	}, {
		.code = MEDIA_BUS_FMT_UYVY8_1X16,
		.csi_format = true,
		.bus_width = 16,
		.bpp = 16,
		.pdformat = PDFORMAT_YUV422_8BIT,
		.pdataf = PDATAF_MODE1,
	}, {
		.code = MEDIA_BUS_FMT_YUYV8_1X16,
		.csi_format = true,
		.bus_width = 16,
		.bpp = 16,
		.pdformat = PDFORMAT_YUV422_8BIT,
		.pdataf = PDATAF_MODE2,
	}, {
		.code = MEDIA_BUS_FMT_UYVY10_2X10,
		.bus_width = 10,
		.bpp = 20,
		.pdformat = PDFORMAT_YUV422_10BIT,
		.pdataf = PDATAF_MODE0, /* don't care */
	},
	TC358746_FORMAT_RAW(8, MEDIA_BUS_FMT_SBGGR8_1X8),
	TC358746_FORMAT_RAW(8, MEDIA_BUS_FMT_SGBRG8_1X8),
	TC358746_FORMAT_RAW(8, MEDIA_BUS_FMT_SGRBG8_1X8),
	TC358746_FORMAT_RAW(8, MEDIA_BUS_FMT_SRGGB8_1X8),
	TC358746_FORMAT_RAW(10, MEDIA_BUS_FMT_SBGGR10_1X10),
	TC358746_FORMAT_RAW(10, MEDIA_BUS_FMT_SGBRG10_1X10),
	TC358746_FORMAT_RAW(10, MEDIA_BUS_FMT_SGRBG10_1X10),
	TC358746_FORMAT_RAW(10, MEDIA_BUS_FMT_SRGGB10_1X10),
	TC358746_FORMAT_RAW(12, MEDIA_BUS_FMT_SBGGR12_1X12),
	TC358746_FORMAT_RAW(12, MEDIA_BUS_FMT_SGBRG12_1X12),
	TC358746_FORMAT_RAW(12, MEDIA_BUS_FMT_SGRBG12_1X12),
	TC358746_FORMAT_RAW(12, MEDIA_BUS_FMT_SRGGB12_1X12),
	TC358746_FORMAT_RAW(14, MEDIA_BUS_FMT_SBGGR14_1X14),
	TC358746_FORMAT_RAW(14, MEDIA_BUS_FMT_SGBRG14_1X14),
	TC358746_FORMAT_RAW(14, MEDIA_BUS_FMT_SGRBG14_1X14),
	TC358746_FORMAT_RAW(14, MEDIA_BUS_FMT_SRGGB14_1X14),
};

/* Get n-th format for pad */
static const struct tc358746_format *
tc358746_get_format_by_idx(unsigned int pad, unsigned int index)
{
	unsigned int idx = 0;
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(tc358746_formats); i++) {
		const struct tc358746_format *fmt = &tc358746_formats[i];

		if ((pad == TC358746_SOURCE && fmt->csi_format) ||
		    (pad == TC358746_SINK)) {
			if (idx == index)
				return fmt;
			idx++;
		}
	}

	return ERR_PTR(-EINVAL);
}

static const struct tc358746_format *
tc358746_get_format_by_code(unsigned int pad, u32 code)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(tc358746_formats); i++) {
		const struct tc358746_format *fmt = &tc358746_formats[i];

		if (pad == TC358746_SINK && fmt->code == code)
			return fmt;

		if (pad == TC358746_SOURCE && !fmt->csi_format)
			continue;

		if (fmt->code == code)
			return fmt;
	}

	return ERR_PTR(-EINVAL);
}

static u32 tc358746_src_mbus_code(u32 code)
{
	switch (code) {
	case MEDIA_BUS_FMT_UYVY8_2X8:
		return MEDIA_BUS_FMT_UYVY8_1X16;
	case MEDIA_BUS_FMT_UYVY10_2X10:
		return MEDIA_BUS_FMT_UYVY10_1X20;
	default:
		return code;
	}
}

static bool tc358746_valid_reg(struct device *dev, unsigned int reg)
{
	switch (reg) {
	case CHIPID_REG ... CSI_START_REG:
		return true;
	default:
		return false;
	}
}

static const struct regmap_config tc358746_regmap_config = {
	.name = "tc358746",
	.reg_bits = 16,
	.val_bits = 16,
	.max_register = CSI_START_REG,
	.writeable_reg = tc358746_valid_reg,
	.readable_reg = tc358746_valid_reg,
	.reg_format_endian = REGMAP_ENDIAN_BIG,
	.val_format_endian = REGMAP_ENDIAN_BIG,
};

static int tc358746_write(struct tc358746 *tc358746, u32 reg, u32 val)
{
	size_t count;
	int err;

	/* 32-bit registers starting from CLW_DPHYCONTTX */
	count = reg < CLW_DPHYCONTTX_REG ? 1 : 2;

	err = regmap_bulk_write(tc358746->regmap, reg, &val, count);
	if (err)
		dev_err(tc358746->sd.dev,
			"Failed to write reg:0x%04x err:%d\n", reg, err);

	return err;
}

static int tc358746_read(struct tc358746 *tc358746, u32 reg, u32 *val)
{
	size_t count;
	int err;

	/* 32-bit registers starting from CLW_DPHYCONTTX */
	count = reg < CLW_DPHYCONTTX_REG ? 1 : 2;
	*val = 0;

	err = regmap_bulk_read(tc358746->regmap, reg, val, count);
	if (err)
		dev_err(tc358746->sd.dev,
			"Failed to read reg:0x%04x err:%d\n", reg, err);

	return err;
}

static int
tc358746_update_bits(struct tc358746 *tc358746, u32 reg, u32 mask, u32 val)
{
	u32 tmp, orig;
	int err;

	err = tc358746_read(tc358746, reg, &orig);
	if (err)
		return err;

	tmp = orig & ~mask;
	tmp |= val & mask;

	return tc358746_write(tc358746, reg, tmp);
}

static int tc358746_set_bits(struct tc358746 *tc358746, u32 reg, u32 bits)
{
	return tc358746_update_bits(tc358746, reg, bits, bits);
}

static int tc358746_clear_bits(struct tc358746 *tc358746, u32 reg, u32 bits)
{
	return tc358746_update_bits(tc358746, reg, bits, 0);
}

static int tc358746_sw_reset(struct tc358746 *tc358746)
{
	int err;

	err = tc358746_set_bits(tc358746, SYSCTL_REG, SRESET);
	if (err)
		return err;

	fsleep(10);

	return tc358746_clear_bits(tc358746, SYSCTL_REG, SRESET);
}

static int
tc358746_apply_pll_config(struct tc358746 *tc358746)
{
	u8 post = tc358746->pll_post_div;
	u16 pre = tc358746->pll_pre_div;
	u16 mul = tc358746->pll_mul;
	u32 val, mask;
	int err;

	err = tc358746_read(tc358746, PLLCTL1_REG, &val);
	if (err)
		return err;

	/* Don't touch the PLL if running */
	if (FIELD_GET(PLL_EN, val) == 1)
		return 0;

	/* Pre-div and Multiplicator have a internal +1 logic */
	val = PLL_PRD(pre - 1) | PLL_FBD(mul - 1);
	mask = PLL_PRD_MASK | PLL_FBD_MASK;
	err = tc358746_update_bits(tc358746, PLLCTL0_REG, mask, val);
	if (err)
		return err;

	val = PLL_FRS(ilog2(post)) | RESETB | PLL_EN;
	mask = PLL_FRS_MASK | RESETB | PLL_EN;
	err = tc358746_update_bits(tc358746, PLLCTL1_REG, mask, val);
	if (err)
		return err;

	fsleep(1000);

	return tc358746_set_bits(tc358746, PLLCTL1_REG, CKEN);
}

#define TC358746_VB_PRECISION		10
#define TC358746_VB_MAX_SIZE		(511 * 32)
#define TC358746_VB_DEFAULT_SIZE	(1 * 32)

static int tc358746_calc_vb_size(struct tc358746 *tc358746,
				 s64 source_link_freq,
				 const struct v4l2_mbus_framefmt *mbusfmt,
				 const struct tc358746_format *fmt)
{
	unsigned long csi_bitrate, source_bitrate;
	unsigned int fifo_sz, tmp, n;
	int vb_size; /* Video buffer size in bits */

	source_bitrate = source_link_freq * fmt->bus_width;

	csi_bitrate = tc358746->dphy_cfg.lanes * tc358746->pll_rate;

	dev_dbg(tc358746->sd.dev,
		"Fifo settings params: source-bitrate:%lu csi-bitrate:%lu",
		source_bitrate, csi_bitrate);

	/* Avoid possible FIFO overflows */
	if (csi_bitrate < source_bitrate)
		return -EINVAL;

	/* Best case */
	if (csi_bitrate == source_bitrate) {
		fifo_sz = TC358746_VB_DEFAULT_SIZE;
		vb_size = TC358746_VB_DEFAULT_SIZE;
	} else {
		/*
		 * Avoid possible FIFO underflow in case of
		 * csi_bitrate > source_bitrate. For such case the chip has a internal
		 * fifo which can be used to delay the line output.
		 *
		 * Fifo size calculation (excluding precision):
		 *
		 * fifo-sz, image-width - in bits
		 * sbr                  - source_bitrate in bits/s
		 * csir                 - csi_bitrate in bits/s
		 *
		 * image-width / csir >= (image-width - fifo-sz) / sbr
		 * image-width * sbr / csir >= image-width - fifo-sz
		 * fifo-sz >= image-width - image-width * sbr / csir; with n = csir/sbr
		 * fifo-sz >= image-width - image-width / n
		 */
		source_bitrate /= TC358746_VB_PRECISION;
		n = csi_bitrate / source_bitrate;
		tmp = (mbusfmt->width * TC358746_VB_PRECISION) / n;
		fifo_sz = mbusfmt->width - tmp;
		fifo_sz *= fmt->bpp;
		vb_size = round_up(fifo_sz, 32);
	}

	dev_dbg(tc358746->sd.dev,
		"Found FIFO size[bits]:%u -> aligned to size[bits]:%u\n",
		fifo_sz, vb_size);

	if (vb_size > TC358746_VB_MAX_SIZE)
		return -EINVAL;

	return vb_size;
}

static int tc358746_apply_misc_config(struct tc358746 *tc358746)
{
	const struct v4l2_mbus_framefmt *mbusfmt;
	struct v4l2_subdev *sd = &tc358746->sd;
	struct v4l2_subdev_state *sink_state;
	const struct tc358746_format *fmt;
	struct device *dev = sd->dev;
	struct media_pad *source_pad;
	s64 source_link_freq;
	int vb_size;
	u32 val;
	int err;

	sink_state = v4l2_subdev_lock_and_get_active_state(sd);

	mbusfmt = v4l2_subdev_state_get_format(sink_state, TC358746_SINK);
	fmt = tc358746_get_format_by_code(TC358746_SINK, mbusfmt->code);

	source_pad = media_entity_remote_source_pad_unique(&sd->entity);
	if (IS_ERR(source_pad)) {
		dev_err(dev, "Failed to get source pad of %s\n", sd->name);
		err = PTR_ERR(source_pad);
		goto out;
	}
	source_link_freq = v4l2_get_link_freq(source_pad, 0, 0);
	if (source_link_freq <= 0) {
		dev_err(dev,
			"Failed to query or invalid source link frequency\n");
		/* Return -EINVAL in case of source_link_freq is 0 */
		err = source_link_freq ?: -EINVAL;
		goto out;
	}

	/* Self defined CSI user data type id's are not supported yet */
	val = PDFMT(fmt->pdformat);
	dev_dbg(dev, "DATAFMT: 0x%x\n", val);
	err = tc358746_write(tc358746, DATAFMT_REG, val);
	if (err)
		goto out;

	val = PDATAF(fmt->pdataf);
	dev_dbg(dev, "CONFCTL[PDATAF]: 0x%x\n", fmt->pdataf);
	err = tc358746_update_bits(tc358746, CONFCTL_REG, PDATAF_MASK, val);
	if (err)
		goto out;

	vb_size = tc358746_calc_vb_size(tc358746, source_link_freq, mbusfmt, fmt);
	if (vb_size < 0) {
		err = vb_size;
		goto out;
	}

	val = vb_size / 32;
	dev_dbg(dev, "FIFOCTL: %u (0x%x)\n", val, val);
	err = tc358746_write(tc358746, FIFOCTL_REG, val);
	if (err)
		goto out;

	/* Total number of bytes for each line/width */
	val = mbusfmt->width * fmt->bpp / 8;
	dev_dbg(dev, "WORDCNT: %u (0x%x)\n", val, val);
	err = tc358746_write(tc358746, WORDCNT_REG, val);

out:
	v4l2_subdev_unlock_state(sink_state);

	return err;
}

static u32 tc358746_cfg_to_cnt(unsigned long cfg_val, unsigned long clk_hz,
			       unsigned long long time_base)
{
	return div64_u64((u64)cfg_val * clk_hz + time_base - 1, time_base);
}

static u32 tc358746_ps_to_cnt(unsigned long cfg_val, unsigned long clk_hz)
{
	return tc358746_cfg_to_cnt(cfg_val, clk_hz, PSEC_PER_SEC);
}

static u32 tc358746_us_to_cnt(unsigned long cfg_val, unsigned long clk_hz)
{
	return tc358746_cfg_to_cnt(cfg_val, clk_hz, USEC_PER_SEC);
}

static int tc358746_apply_dphy_config(struct tc358746 *tc358746)
{
	struct phy_configure_opts_mipi_dphy *cfg = &tc358746->dphy_cfg;
	bool non_cont_clk = !!(tc358746->csi_vep.bus.mipi_csi2.flags &
			       V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK);
	struct device *dev = tc358746->sd.dev;
	unsigned long hs_byte_clk, hf_clk;
	u32 val, val2, lptxcnt;
	int err;

	/* The hs_byte_clk is also called SYSCLK in the excel sheet */
	hs_byte_clk = cfg->hs_clk_rate / 8;
	hf_clk = hs_byte_clk / 2;

	val = tc358746_us_to_cnt(cfg->init, hf_clk) - 1;
	dev_dbg(dev, "LINEINITCNT: %u (0x%x)\n", val, val);
	err = tc358746_write(tc358746, LINEINITCNT_REG, val);
	if (err)
		return err;

	val = tc358746_ps_to_cnt(cfg->lpx, hs_byte_clk) - 1;
	lptxcnt = val;
	dev_dbg(dev, "LPTXTIMECNT: %u (0x%x)\n", val, val);
	err = tc358746_write(tc358746, LPTXTIMECNT_REG, val);
	if (err)
		return err;

	val = tc358746_ps_to_cnt(cfg->clk_prepare, hs_byte_clk) - 1;
	val2 = tc358746_ps_to_cnt(cfg->clk_zero, hs_byte_clk) - 1;
	dev_dbg(dev, "TCLK_PREPARECNT: %u (0x%x)\n", val, val);
	dev_dbg(dev, "TCLK_ZEROCNT: %u (0x%x)\n", val2, val2);
	dev_dbg(dev, "TCLK_HEADERCNT: 0x%x\n",
		(u32)(TCLK_PREPARECNT(val) | TCLK_ZEROCNT(val2)));
	err = tc358746_write(tc358746, TCLK_HEADERCNT_REG,
			     TCLK_PREPARECNT(val) | TCLK_ZEROCNT(val2));
	if (err)
		return err;

	val = tc358746_ps_to_cnt(cfg->clk_trail, hs_byte_clk);
	dev_dbg(dev, "TCLK_TRAILCNT: %u (0x%x)\n", val, val);
	err = tc358746_write(tc358746, TCLK_TRAILCNT_REG, val);
	if (err)
		return err;

	val = tc358746_ps_to_cnt(cfg->hs_prepare, hs_byte_clk) - 1;
	val2 = tc358746_ps_to_cnt(cfg->hs_zero, hs_byte_clk) - 1;
	dev_dbg(dev, "THS_PREPARECNT: %u (0x%x)\n", val, val);
	dev_dbg(dev, "THS_ZEROCNT: %u (0x%x)\n", val2, val2);
	dev_dbg(dev, "THS_HEADERCNT: 0x%x\n",
		(u32)(THS_PREPARECNT(val) | THS_ZEROCNT(val2)));
	err = tc358746_write(tc358746, THS_HEADERCNT_REG,
			     THS_PREPARECNT(val) | THS_ZEROCNT(val2));
	if (err)
		return err;

	/* TWAKEUP > 1ms in lptxcnt steps */
	val = tc358746_us_to_cnt(cfg->wakeup, hs_byte_clk);
	val = val / (lptxcnt + 1) - 1;
	dev_dbg(dev, "TWAKEUP: %u (0x%x)\n", val, val);
	err = tc358746_write(tc358746, TWAKEUP_REG, val);
	if (err)
		return err;

	val = tc358746_ps_to_cnt(cfg->clk_post, hs_byte_clk);
	dev_dbg(dev, "TCLK_POSTCNT: %u (0x%x)\n", val, val);
	err = tc358746_write(tc358746, TCLK_POSTCNT_REG, val);
	if (err)
		return err;

	val = tc358746_ps_to_cnt(cfg->hs_trail, hs_byte_clk);
	dev_dbg(dev, "THS_TRAILCNT: %u (0x%x)\n", val, val);
	err = tc358746_write(tc358746, THS_TRAILCNT_REG, val);
	if (err)
		return err;

	dev_dbg(dev, "CONTCLKMODE: %u", non_cont_clk ? 0 : 1);

	return  tc358746_write(tc358746, TXOPTIONCNTRL_REG, non_cont_clk ? 0 : 1);
}

#define MAX_DATA_LANES 4

static int tc358746_enable_csi_lanes(struct tc358746 *tc358746, int enable)
{
	unsigned int lanes = tc358746->dphy_cfg.lanes;
	unsigned int lane;
	u32 reg, val;
	int err;

	err = tc358746_update_bits(tc358746, CONFCTL_REG, DATALANE_MASK,
				   lanes - 1);
	if (err)
		return err;

	/* Clock lane */
	val = enable ? 0 : LANEDISABLE;
	dev_dbg(tc358746->sd.dev, "CLW_CNTRL: 0x%x\n", val);
	err = tc358746_write(tc358746, CLW_CNTRL_REG, val);
	if (err)
		return err;

	for (lane = 0; lane < MAX_DATA_LANES; lane++) {
		/* Data lanes */
		reg = D0W_CNTRL_REG + lane * 0x4;
		val = (enable && lane < lanes) ? 0 : LANEDISABLE;

		dev_dbg(tc358746->sd.dev, "D%uW_CNTRL: 0x%x\n", lane, val);
		err = tc358746_write(tc358746, reg, val);
		if (err)
			return err;
	}

	val = 0;
	if (enable) {
		/* Clock lane */
		val |= BIT(0);

		/* Data lanes */
		for (lane = 1; lane <= lanes; lane++)
			val |= BIT(lane);
	}

	dev_dbg(tc358746->sd.dev, "HSTXVREGEN: 0x%x\n", val);

	return tc358746_write(tc358746, HSTXVREGEN_REG, val);
}

static int tc358746_enable_csi_module(struct tc358746 *tc358746, int enable)
{
	unsigned int lanes = tc358746->dphy_cfg.lanes;
	int err;

	/*
	 * START and STRT are only reseted/disabled by sw reset. This is
	 * required to put the lane state back into LP-11 state. The sw reset
	 * don't reset register values.
	 */
	if (!enable)
		return tc358746_sw_reset(tc358746);

	err = tc358746_write(tc358746, STARTCNTRL_REG, START);
	if (err)
		return err;

	err = tc358746_write(tc358746, CSI_START_REG, STRT);
	if (err)
		return err;

	/* CSI_CONTROL_REG is only indirect accessible */
	return tc358746_write(tc358746, CSI_CONFW_REG,
			      MODE(MODE_SET) |
			      ADDRESS(CSI_CONTROL_ADDRESS) |
			      DATA(CSI_MODE | TXHSMD | NOL(lanes - 1)));
}

static int tc358746_enable_parallel_port(struct tc358746 *tc358746, int enable)
{
	int err;

	if (enable) {
		err = tc358746_write(tc358746, PP_MISC_REG, 0);
		if (err)
			return err;

		return tc358746_set_bits(tc358746, CONFCTL_REG, PPEN);
	}

	err = tc358746_set_bits(tc358746, PP_MISC_REG, FRMSTOP);
	if (err)
		return err;

	err = tc358746_clear_bits(tc358746, CONFCTL_REG, PPEN);
	if (err)
		return err;

	return tc358746_set_bits(tc358746, PP_MISC_REG, RSTPTR);
}

static inline struct v4l2_subdev *tc358746_get_remote_sd(struct media_pad *pad)
{
	pad = media_pad_remote_pad_first(pad);
	if (!pad)
		return NULL;

	return media_entity_to_v4l2_subdev(pad->entity);
}

static int tc358746_s_stream(struct v4l2_subdev *sd, int enable)
{
	struct tc358746 *tc358746 = to_tc358746(sd);
	struct v4l2_subdev *src;
	int err;

	dev_dbg(sd->dev, "%sable\n", enable ? "en" : "dis");

	src = tc358746_get_remote_sd(&tc358746->pads[TC358746_SINK]);
	if (!src)
		return -EPIPE;

	if (enable) {
		err = pm_runtime_resume_and_get(sd->dev);
		if (err)
			return err;

		err = tc358746_apply_dphy_config(tc358746);
		if (err)
			goto err_out;

		err = tc358746_apply_misc_config(tc358746);
		if (err)
			goto err_out;

		err = tc358746_enable_csi_lanes(tc358746, 1);
		if (err)
			goto err_out;

		err = tc358746_enable_csi_module(tc358746, 1);
		if (err)
			goto err_out;

		err = tc358746_enable_parallel_port(tc358746, 1);
		if (err)
			goto err_out;

		err = v4l2_subdev_call(src, video, s_stream, 1);
		if (err)
			goto err_out;

		return 0;

err_out:
		pm_runtime_put_sync_autosuspend(sd->dev);

		return err;
	}

	/*
	 * The lanes must be disabled first (before the csi module) so the
	 * LP-11 state is entered correctly.
	 */
	err = tc358746_enable_csi_lanes(tc358746, 0);
	if (err)
		return err;

	err = tc358746_enable_csi_module(tc358746, 0);
	if (err)
		return err;

	err = tc358746_enable_parallel_port(tc358746, 0);
	if (err)
		return err;

	pm_runtime_put_sync_autosuspend(sd->dev);

	return v4l2_subdev_call(src, video, s_stream, 0);
}

static int tc358746_init_state(struct v4l2_subdev *sd,
			       struct v4l2_subdev_state *state)
{
	struct v4l2_mbus_framefmt *fmt;

	fmt = v4l2_subdev_state_get_format(state, TC358746_SINK);
	*fmt = tc358746_def_fmt;

	fmt = v4l2_subdev_state_get_format(state, TC358746_SOURCE);
	*fmt = tc358746_def_fmt;
	fmt->code = tc358746_src_mbus_code(tc358746_def_fmt.code);

	return 0;
}

static int tc358746_enum_mbus_code(struct v4l2_subdev *sd,
				   struct v4l2_subdev_state *sd_state,
				   struct v4l2_subdev_mbus_code_enum *code)
{
	const struct tc358746_format *fmt;

	fmt = tc358746_get_format_by_idx(code->pad, code->index);
	if (IS_ERR(fmt))
		return PTR_ERR(fmt);

	code->code = fmt->code;

	return 0;
}

static int tc358746_set_fmt(struct v4l2_subdev *sd,
			    struct v4l2_subdev_state *sd_state,
			    struct v4l2_subdev_format *format)
{
	struct v4l2_mbus_framefmt *src_fmt, *sink_fmt;
	const struct tc358746_format *fmt;

	/* Source follows the sink */
	if (format->pad == TC358746_SOURCE)
		return v4l2_subdev_get_fmt(sd, sd_state, format);

	sink_fmt = v4l2_subdev_state_get_format(sd_state, TC358746_SINK);

	fmt = tc358746_get_format_by_code(format->pad, format->format.code);
	if (IS_ERR(fmt)) {
		fmt = tc358746_get_format_by_code(format->pad, tc358746_def_fmt.code);
		// Can't happen, but just in case...
		if (WARN_ON(IS_ERR(fmt)))
			return -EINVAL;
	}

	format->format.code = fmt->code;
	format->format.field = V4L2_FIELD_NONE;

	dev_dbg(sd->dev, "Update format: %ux%u code:0x%x -> %ux%u code:0x%x",
		sink_fmt->width, sink_fmt->height, sink_fmt->code,
		format->format.width, format->format.height, format->format.code);

	*sink_fmt = format->format;

	src_fmt = v4l2_subdev_state_get_format(sd_state, TC358746_SOURCE);
	*src_fmt = *sink_fmt;
	src_fmt->code = tc358746_src_mbus_code(sink_fmt->code);

	return 0;
}

static unsigned long tc358746_find_pll_settings(struct tc358746 *tc358746,
						unsigned long refclk,
						unsigned long fout)

{
	struct device *dev = tc358746->sd.dev;
	unsigned long best_freq = 0;
	u32 min_delta = 0xffffffff;
	u16 prediv_max = 17;
	u16 prediv_min = 1;
	u16 m_best = 0, mul;
	u16 p_best = 1, p;
	u8 postdiv;

	if (fout > 1000 * HZ_PER_MHZ) {
		dev_err(dev, "HS-Clock above 1 Ghz are not supported\n");
		return 0;
	}

	if (fout >= 500 * HZ_PER_MHZ)
		postdiv = 1;
	else if (fout >= 250 * HZ_PER_MHZ)
		postdiv = 2;
	else if (fout >= 125 * HZ_PER_MHZ)
		postdiv = 4;
	else
		postdiv = 8;

	for (p = prediv_min; p <= prediv_max; p++) {
		unsigned long delta, fin;
		u64 tmp;

		fin = DIV_ROUND_CLOSEST(refclk, p);
		if (fin < 4 * HZ_PER_MHZ || fin > 40 * HZ_PER_MHZ)
			continue;

		tmp = fout * postdiv;
		mul = div64_ul(tmp, fin);
		if (mul > 511)
			continue;

		tmp = mul * fin;
		do_div(tmp, postdiv);

		delta = abs(fout - tmp);
		if (delta < min_delta) {
			p_best = p;
			m_best = mul;
			min_delta = delta;
			best_freq = tmp;
		}

		if (delta == 0)
			break;
	}

	if (!best_freq) {
		dev_err(dev, "Failed find PLL frequency\n");
		return 0;
	}

	tc358746->pll_post_div = postdiv;
	tc358746->pll_pre_div = p_best;
	tc358746->pll_mul = m_best;

	if (best_freq != fout)
		dev_warn(dev, "Request PLL freq:%lu, found PLL freq:%lu\n",
			 fout, best_freq);

	dev_dbg(dev, "Found PLL settings: freq:%lu prediv:%u multi:%u postdiv:%u\n",
		best_freq, p_best, m_best, postdiv);

	return best_freq;
}

static int tc358746_get_mbus_config(struct v4l2_subdev *sd, unsigned int pad,
				    struct v4l2_mbus_config *config)
{
	struct tc358746 *tc358746 = to_tc358746(sd);

	if (pad != TC358746_SOURCE)
		return -EINVAL;

	config->type = V4L2_MBUS_CSI2_DPHY;
	config->bus.mipi_csi2 = tc358746->csi_vep.bus.mipi_csi2;

	return 0;
}

static int __maybe_unused
tc358746_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
{
	struct tc358746 *tc358746 = to_tc358746(sd);
	u32 val;
	int err;

	/* 32-bit registers starting from CLW_DPHYCONTTX */
	reg->size = reg->reg < CLW_DPHYCONTTX_REG ? 2 : 4;

	if (!pm_runtime_get_if_in_use(sd->dev))
		return 0;

	err = tc358746_read(tc358746, reg->reg, &val);
	reg->val = val;

	pm_runtime_put_sync_autosuspend(sd->dev);

	return err;
}

static int __maybe_unused
tc358746_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
{
	struct tc358746 *tc358746 = to_tc358746(sd);

	if (!pm_runtime_get_if_in_use(sd->dev))
		return 0;

	tc358746_write(tc358746, (u32)reg->reg, (u32)reg->val);

	pm_runtime_put_sync_autosuspend(sd->dev);

	return 0;
}

static const struct v4l2_subdev_core_ops tc358746_core_ops = {
#ifdef CONFIG_VIDEO_ADV_DEBUG
	.g_register = tc358746_g_register,
	.s_register = tc358746_s_register,
#endif
};

static const struct v4l2_subdev_video_ops tc358746_video_ops = {
	.s_stream = tc358746_s_stream,
};

static const struct v4l2_subdev_pad_ops tc358746_pad_ops = {
	.enum_mbus_code = tc358746_enum_mbus_code,
	.set_fmt = tc358746_set_fmt,
	.get_fmt = v4l2_subdev_get_fmt,
	.link_validate = v4l2_subdev_link_validate_default,
	.get_mbus_config = tc358746_get_mbus_config,
};

static const struct v4l2_subdev_ops tc358746_ops = {
	.core = &tc358746_core_ops,
	.video = &tc358746_video_ops,
	.pad = &tc358746_pad_ops,
};

static const struct v4l2_subdev_internal_ops tc358746_internal_ops = {
	.init_state = tc358746_init_state,
};

static const struct media_entity_operations tc358746_entity_ops = {
	.get_fwnode_pad = v4l2_subdev_get_fwnode_pad_1_to_1,
	.link_validate = v4l2_subdev_link_validate,
};

static int tc358746_mclk_enable(struct clk_hw *hw)
{
	struct tc358746 *tc358746 = clk_hw_to_tc358746(hw);
	unsigned int div;
	u32 val;
	int err;

	div = tc358746->mclk_postdiv / 2;
	val = MCLK_HIGH(div - 1) | MCLK_LOW(div - 1);
	dev_dbg(tc358746->sd.dev, "MCLKCTL: %u (0x%x)\n", val, val);
	err = tc358746_write(tc358746, MCLKCTL_REG, val);
	if (err)
		return err;

	if (tc358746->mclk_prediv == 8)
		val = MCLKDIV(MCLKDIV_8);
	else if (tc358746->mclk_prediv == 4)
		val = MCLKDIV(MCLKDIV_4);
	else
		val = MCLKDIV(MCLKDIV_2);

	dev_dbg(tc358746->sd.dev, "CLKCTL[MCLKDIV]: %u (0x%x)\n", val, val);

	return tc358746_update_bits(tc358746, CLKCTL_REG, MCLKDIV_MASK, val);
}

static void tc358746_mclk_disable(struct clk_hw *hw)
{
	struct tc358746 *tc358746 = clk_hw_to_tc358746(hw);

	tc358746_write(tc358746, MCLKCTL_REG, 0);
}

static long
tc358746_find_mclk_settings(struct tc358746 *tc358746, unsigned long mclk_rate)
{
	unsigned long pll_rate = tc358746->pll_rate;
	const unsigned char prediv[] = { 2, 4, 8 };
	unsigned int mclk_prediv, mclk_postdiv;
	struct device *dev = tc358746->sd.dev;
	unsigned int postdiv, mclkdiv;
	unsigned long best_mclk_rate;
	unsigned int i;

	/*
	 *                          MCLK-Div
	 *           -------------------´`---------------------
	 *          ´                                          `
	 *         +-------------+     +------------------------+
	 *         | MCLK-PreDiv |     |       MCLK-PostDiv     |
	 * PLL --> |   (2/4/8)   | --> | (mclk_low + mclk_high) | --> MCLK
	 *         +-------------+     +------------------------+
	 *
	 * The register value of mclk_low/high is mclk_low/high+1, i.e.:
	 *   mclk_low/high = 1   --> 2 MCLK-Ref Counts
	 *   mclk_low/high = 255 --> 256 MCLK-Ref Counts == max.
	 * If mclk_low and mclk_high are 0 then MCLK is disabled.
	 *
	 * Keep it simple and support 50/50 duty cycles only for now,
	 * so the calc will be:
	 *
	 *   MCLK = PLL / (MCLK-PreDiv * 2 * MCLK-PostDiv)
	 */

	if (mclk_rate == tc358746->mclk_rate)
		return mclk_rate;

	/* Highest possible rate */
	mclkdiv = pll_rate / mclk_rate;
	if (mclkdiv <= 8) {
		mclk_prediv = 2;
		mclk_postdiv = 4;
		best_mclk_rate = pll_rate / (2 * 4);
		goto out;
	}

	/* First check the prediv */
	for (i = 0; i < ARRAY_SIZE(prediv); i++) {
		postdiv = mclkdiv / prediv[i];

		if (postdiv % 2)
			continue;

		if (postdiv >= 4 && postdiv <= 512) {
			mclk_prediv = prediv[i];
			mclk_postdiv = postdiv;
			best_mclk_rate = pll_rate / (prediv[i] * postdiv);
			goto out;
		}
	}

	/* No suitable prediv found, so try to adjust the postdiv */
	for (postdiv = 4; postdiv <= 512; postdiv += 2) {
		unsigned int pre;

		pre = mclkdiv / postdiv;
		if (pre == 2 || pre == 4 || pre == 8) {
			mclk_prediv = pre;
			mclk_postdiv = postdiv;
			best_mclk_rate = pll_rate / (pre * postdiv);
			goto out;
		}
	}

	/* The MCLK <-> PLL gap is to high -> use largest possible div */
	mclk_prediv = 8;
	mclk_postdiv = 512;
	best_mclk_rate = pll_rate / (8 * 512);

out:
	tc358746->mclk_prediv = mclk_prediv;
	tc358746->mclk_postdiv = mclk_postdiv;
	tc358746->mclk_rate = best_mclk_rate;

	if (best_mclk_rate != mclk_rate)
		dev_warn(dev, "Request MCLK freq:%lu, found MCLK freq:%lu\n",
			 mclk_rate, best_mclk_rate);

	dev_dbg(dev, "Found MCLK settings: freq:%lu prediv:%u postdiv:%u\n",
		best_mclk_rate, mclk_prediv, mclk_postdiv);

	return best_mclk_rate;
}

static unsigned long
tc358746_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
{
	struct tc358746 *tc358746 = clk_hw_to_tc358746(hw);
	unsigned int prediv, postdiv;
	u32 val;
	int err;

	err = tc358746_read(tc358746, MCLKCTL_REG, &val);
	if (err)
		return 0;

	postdiv = FIELD_GET(MCLK_LOW_MASK, val) + 1;
	postdiv += FIELD_GET(MCLK_HIGH_MASK, val) + 1;

	err = tc358746_read(tc358746, CLKCTL_REG, &val);
	if (err)
		return 0;

	prediv = FIELD_GET(MCLKDIV_MASK, val);
	if (prediv == MCLKDIV_8)
		prediv = 8;
	else if (prediv == MCLKDIV_4)
		prediv = 4;
	else
		prediv = 2;

	return tc358746->pll_rate / (prediv * postdiv);
}

static int tc358746_mclk_determine_rate(struct clk_hw *hw,
					struct clk_rate_request *req)
{
	struct tc358746 *tc358746 = clk_hw_to_tc358746(hw);

	req->best_parent_rate = tc358746->pll_rate;

	req->rate = tc358746_find_mclk_settings(tc358746, req->rate);

	return 0;
}

static int tc358746_mclk_set_rate(struct clk_hw *hw, unsigned long rate,
				  unsigned long parent_rate)
{
	struct tc358746 *tc358746 = clk_hw_to_tc358746(hw);

	tc358746_find_mclk_settings(tc358746, rate);

	return tc358746_mclk_enable(hw);
}

static const struct clk_ops tc358746_mclk_ops = {
	.enable = tc358746_mclk_enable,
	.disable = tc358746_mclk_disable,
	.recalc_rate = tc358746_recalc_rate,
	.determine_rate = tc358746_mclk_determine_rate,
	.set_rate = tc358746_mclk_set_rate,
};

static int tc358746_setup_mclk_provider(struct tc358746 *tc358746)
{
	struct clk_init_data mclk_initdata = { };
	struct device *dev = tc358746->sd.dev;
	const char *mclk_name;
	int err;

	/* MCLK clk provider support is optional */
	if (!device_property_present(dev, "#clock-cells"))
		return 0;

	/* Init to highest possibel MCLK */
	tc358746->mclk_postdiv = 512;
	tc358746->mclk_prediv = 8;

	mclk_name = "tc358746-mclk";
	device_property_read_string(dev, "clock-output-names", &mclk_name);

	mclk_initdata.name = mclk_name;
	mclk_initdata.ops = &tc358746_mclk_ops;
	tc358746->mclk_hw.init = &mclk_initdata;

	err = devm_clk_hw_register(dev, &tc358746->mclk_hw);
	if (err) {
		dev_err(dev, "Failed to register mclk provider\n");
		return err;
	}

	err = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
					  &tc358746->mclk_hw);
	if (err)
		dev_err(dev, "Failed to add mclk provider\n");

	return err;
}

static int
tc358746_init_subdev(struct tc358746 *tc358746, struct i2c_client *client)
{
	struct v4l2_subdev *sd = &tc358746->sd;
	int err;

	v4l2_i2c_subdev_init(sd, client, &tc358746_ops);
	sd->internal_ops = &tc358746_internal_ops;
	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
	sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
	sd->entity.ops = &tc358746_entity_ops;

	tc358746->pads[TC358746_SINK].flags = MEDIA_PAD_FL_SINK;
	tc358746->pads[TC358746_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
	err = media_entity_pads_init(&sd->entity, TC358746_NR_PADS,
				     tc358746->pads);
	if (err)
		return err;

	err = v4l2_subdev_init_finalize(sd);
	if (err)
		media_entity_cleanup(&sd->entity);

	return err;
}

static int
tc358746_init_output_port(struct tc358746 *tc358746, unsigned long refclk)
{
	struct device *dev = tc358746->sd.dev;
	struct v4l2_fwnode_endpoint *vep;
	unsigned long csi_link_rate;
	struct fwnode_handle *ep;
	unsigned char csi_lanes;
	int err;

	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), TC358746_SOURCE,
					     0, 0);
	if (!ep) {
		dev_err(dev, "Missing endpoint node\n");
		return -EINVAL;
	}

	/* Currently we only support 'parallel in' -> 'csi out' */
	vep = &tc358746->csi_vep;
	vep->bus_type = V4L2_MBUS_CSI2_DPHY;
	err = v4l2_fwnode_endpoint_alloc_parse(ep, vep);
	fwnode_handle_put(ep);
	if (err) {
		dev_err(dev, "Failed to parse source endpoint\n");
		return err;
	}

	csi_lanes = vep->bus.mipi_csi2.num_data_lanes;
	if (csi_lanes == 0 || csi_lanes > 4 ||
	    vep->nr_of_link_frequencies == 0) {
		dev_err(dev, "error: Invalid CSI-2 settings\n");
		err = -EINVAL;
		goto err;
	}

	/* TODO: Add support to handle multiple link frequencies */
	csi_link_rate = (unsigned long)vep->link_frequencies[0];
	tc358746->pll_rate = tc358746_find_pll_settings(tc358746, refclk,
							csi_link_rate * 2);
	if (!tc358746->pll_rate) {
		err = -EINVAL;
		goto err;
	}

	err = phy_mipi_dphy_get_default_config_for_hsclk(tc358746->pll_rate,
						csi_lanes, &tc358746->dphy_cfg);
	if (err)
		goto err;

	return 0;

err:
	v4l2_fwnode_endpoint_free(vep);

	return err;
}

static int tc358746_init_hw(struct tc358746 *tc358746)
{
	struct device *dev = tc358746->sd.dev;
	unsigned int chipid;
	u32 val;
	int err;

	err = pm_runtime_resume_and_get(dev);
	if (err < 0) {
		dev_err(dev, "Failed to resume the device\n");
		return err;
	}

	 /* Ensure that CSI interface is put into LP-11 state */
	err = tc358746_sw_reset(tc358746);
	if (err) {
		pm_runtime_put_sync(dev);
		dev_err(dev, "Failed to reset the device\n");
		return err;
	}

	err = tc358746_read(tc358746, CHIPID_REG, &val);
	pm_runtime_put_sync_autosuspend(dev);
	if (err)
		return -ENODEV;

	chipid = FIELD_GET(CHIPID, val);
	if (chipid != 0x44) {
		dev_err(dev, "Invalid chipid 0x%02x\n", chipid);
		return -ENODEV;
	}

	return 0;
}

static int tc358746_init_controls(struct tc358746 *tc358746)
{
	u64 *link_frequencies = tc358746->csi_vep.link_frequencies;
	struct v4l2_ctrl *ctrl;
	int err;

	err = v4l2_ctrl_handler_init(&tc358746->ctrl_hdl, 1);
	if (err)
		return err;

	/*
	 * The driver currently supports only one link-frequency, regardless of
	 * the input from the firmware, see: tc358746_init_output_port(). So
	 * report only the first frequency from the array of possible given
	 * frequencies.
	 */
	ctrl = v4l2_ctrl_new_int_menu(&tc358746->ctrl_hdl, NULL,
				      V4L2_CID_LINK_FREQ, 0, 0,
				      link_frequencies);
	if (ctrl)
		ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;

	err = tc358746->ctrl_hdl.error;
	if (err) {
		v4l2_ctrl_handler_free(&tc358746->ctrl_hdl);
		return err;
	}

	tc358746->sd.ctrl_handler = &tc358746->ctrl_hdl;

	return 0;
}

static int tc358746_notify_bound(struct v4l2_async_notifier *notifier,
				 struct v4l2_subdev *sd,
				 struct v4l2_async_connection *asd)
{
	struct tc358746 *tc358746 =
		container_of(notifier, struct tc358746, notifier);
	u32 flags = MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE;
	struct media_pad *sink = &tc358746->pads[TC358746_SINK];

	return v4l2_create_fwnode_links_to_pad(sd, sink, flags);
}

static const struct v4l2_async_notifier_operations tc358746_notify_ops = {
	.bound = tc358746_notify_bound,
};

static int tc358746_async_register(struct tc358746 *tc358746)
{
	struct v4l2_fwnode_endpoint vep = {
		.bus_type = V4L2_MBUS_PARALLEL,
	};
	struct v4l2_async_connection *asd;
	struct fwnode_handle *ep;
	int err;

	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(tc358746->sd.dev),
					     TC358746_SINK, 0, 0);
	if (!ep)
		return -ENOTCONN;

	err = v4l2_fwnode_endpoint_parse(ep, &vep);
	if (err) {
		fwnode_handle_put(ep);
		return err;
	}

	v4l2_async_subdev_nf_init(&tc358746->notifier, &tc358746->sd);
	asd = v4l2_async_nf_add_fwnode_remote(&tc358746->notifier, ep,
					      struct v4l2_async_connection);
	fwnode_handle_put(ep);

	if (IS_ERR(asd)) {
		err = PTR_ERR(asd);
		goto err_cleanup;
	}

	tc358746->notifier.ops = &tc358746_notify_ops;

	err = v4l2_async_nf_register(&tc358746->notifier);
	if (err)
		goto err_cleanup;

	err = v4l2_async_register_subdev(&tc358746->sd);
	if (err)
		goto err_unregister;

	return 0;

err_unregister:
	v4l2_async_nf_unregister(&tc358746->notifier);
err_cleanup:
	v4l2_async_nf_cleanup(&tc358746->notifier);

	return err;
}

static int tc358746_probe(struct i2c_client *client)
{
	struct device *dev = &client->dev;
	struct tc358746 *tc358746;
	unsigned long refclk;
	unsigned int i;
	int err;

	tc358746 = devm_kzalloc(&client->dev, sizeof(*tc358746), GFP_KERNEL);
	if (!tc358746)
		return -ENOMEM;

	tc358746->regmap = devm_regmap_init_i2c(client, &tc358746_regmap_config);
	if (IS_ERR(tc358746->regmap))
		return dev_err_probe(dev, PTR_ERR(tc358746->regmap),
				     "Failed to init regmap\n");

	tc358746->refclk = devm_clk_get(dev, "refclk");
	if (IS_ERR(tc358746->refclk))
		return dev_err_probe(dev, PTR_ERR(tc358746->refclk),
				     "Failed to get refclk\n");

	err = clk_prepare_enable(tc358746->refclk);
	if (err)
		return dev_err_probe(dev, err,
				     "Failed to enable refclk\n");

	refclk = clk_get_rate(tc358746->refclk);
	clk_disable_unprepare(tc358746->refclk);

	if (refclk < 6 * HZ_PER_MHZ || refclk > 40 * HZ_PER_MHZ)
		return dev_err_probe(dev, -EINVAL, "Invalid refclk range\n");

	for (i = 0; i < ARRAY_SIZE(tc358746_supplies); i++)
		tc358746->supplies[i].supply = tc358746_supplies[i];

	err = devm_regulator_bulk_get(dev, ARRAY_SIZE(tc358746_supplies),
				      tc358746->supplies);
	if (err)
		return dev_err_probe(dev, err, "Failed to get supplies\n");

	tc358746->reset_gpio = devm_gpiod_get_optional(dev, "reset",
						       GPIOD_OUT_HIGH);
	if (IS_ERR(tc358746->reset_gpio))
		return dev_err_probe(dev, PTR_ERR(tc358746->reset_gpio),
				     "Failed to get reset-gpios\n");

	err = tc358746_init_subdev(tc358746, client);
	if (err)
		return dev_err_probe(dev, err, "Failed to init subdev\n");

	err = tc358746_init_output_port(tc358746, refclk);
	if (err)
		goto err_subdev;

	/*
	 * Keep this order since we need the output port link-frequencies
	 * information.
	 */
	err = tc358746_init_controls(tc358746);
	if (err)
		goto err_fwnode;

	dev_set_drvdata(dev, tc358746);

	/* Set to 1sec to give the stream reconfiguration enough time */
	pm_runtime_set_autosuspend_delay(dev, 1000);
	pm_runtime_use_autosuspend(dev);
	pm_runtime_enable(dev);

	err = tc358746_init_hw(tc358746);
	if (err)
		goto err_pm;

	err = tc358746_setup_mclk_provider(tc358746);
	if (err)
		goto err_pm;

	err = tc358746_async_register(tc358746);
	if (err < 0)
		goto err_pm;

	dev_dbg(dev, "%s found @ 0x%x (%s)\n", client->name,
		client->addr, client->adapter->name);

	return 0;

err_pm:
	pm_runtime_disable(dev);
	pm_runtime_set_suspended(dev);
	pm_runtime_dont_use_autosuspend(dev);
	v4l2_ctrl_handler_free(&tc358746->ctrl_hdl);
err_fwnode:
	v4l2_fwnode_endpoint_free(&tc358746->csi_vep);
err_subdev:
	v4l2_subdev_cleanup(&tc358746->sd);
	media_entity_cleanup(&tc358746->sd.entity);

	return err;
}

static void tc358746_remove(struct i2c_client *client)
{
	struct v4l2_subdev *sd = i2c_get_clientdata(client);
	struct tc358746 *tc358746 = to_tc358746(sd);

	v4l2_subdev_cleanup(sd);
	v4l2_ctrl_handler_free(&tc358746->ctrl_hdl);
	v4l2_fwnode_endpoint_free(&tc358746->csi_vep);
	v4l2_async_nf_unregister(&tc358746->notifier);
	v4l2_async_nf_cleanup(&tc358746->notifier);
	v4l2_async_unregister_subdev(sd);
	media_entity_cleanup(&sd->entity);

	pm_runtime_disable(sd->dev);
	pm_runtime_set_suspended(sd->dev);
	pm_runtime_dont_use_autosuspend(sd->dev);
}

/*
 * This function has been created just to avoid a smatch warning,
 * please do not merge it into tc358746_suspend until you have
 * confirmed that it does not introduce a new warning.
 */
static void tc358746_clk_enable(struct tc358746 *tc358746)
{
	clk_prepare_enable(tc358746->refclk);
}

static int tc358746_suspend(struct device *dev)
{
	struct tc358746 *tc358746 = dev_get_drvdata(dev);
	int err;

	clk_disable_unprepare(tc358746->refclk);

	err = regulator_bulk_disable(ARRAY_SIZE(tc358746_supplies),
				     tc358746->supplies);
	if (err)
		tc358746_clk_enable(tc358746);

	return err;
}

static int tc358746_resume(struct device *dev)
{
	struct tc358746 *tc358746 = dev_get_drvdata(dev);
	int err;

	gpiod_set_value(tc358746->reset_gpio, 1);

	err = regulator_bulk_enable(ARRAY_SIZE(tc358746_supplies),
				    tc358746->supplies);
	if (err)
		return err;

	/* min. 200ns */
	usleep_range(10, 20);

	gpiod_set_value(tc358746->reset_gpio, 0);

	err = clk_prepare_enable(tc358746->refclk);
	if (err)
		goto err;

	/* min. 700us ... 1ms */
	usleep_range(1000, 1500);

	/*
	 * Enable the PLL here since it can be called by the clk-framework or by
	 * the .s_stream() callback. So this is the common place for both.
	 */
	err = tc358746_apply_pll_config(tc358746);
	if (err)
		goto err_clk;

	return 0;

err_clk:
	clk_disable_unprepare(tc358746->refclk);
err:
	regulator_bulk_disable(ARRAY_SIZE(tc358746_supplies),
			       tc358746->supplies);
	return err;
}

static DEFINE_RUNTIME_DEV_PM_OPS(tc358746_pm_ops, tc358746_suspend,
				 tc358746_resume, NULL);

static const struct of_device_id __maybe_unused tc358746_of_match[] = {
	{ .compatible = "toshiba,tc358746" },
	{ },
};
MODULE_DEVICE_TABLE(of, tc358746_of_match);

static struct i2c_driver tc358746_driver = {
	.driver = {
		.name = "tc358746",
		.pm = pm_ptr(&tc358746_pm_ops),
		.of_match_table = tc358746_of_match,
	},
	.probe = tc358746_probe,
	.remove = tc358746_remove,
};

module_i2c_driver(tc358746_driver);

MODULE_DESCRIPTION("Toshiba TC358746 Parallel to CSI-2 bridge driver");
MODULE_AUTHOR("Marco Felsch <kernel@pengutronix.de>");
MODULE_LICENSE("GPL");