drivers/media/platform/rcar-vin/rcar-csi2.c

/*
 * Driver for Renesas R-Car MIPI CSI-2 Receiver
 *
 * Copyright (C) 2017 Renesas Electronics Corp.
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */

#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_graph.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>

#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-mc.h>
#include <media/v4l2-subdev.h>

/* Register offsets and bits */

/* Control Timing Select */
#define TREF_REG			0x00
#define TREF_TREF			(1 << 0)

/* Software Reset */
#define SRST_REG			0x04
#define SRST_SRST			(1 << 0)

/* PHY Operation Control */
#define PHYCNT_REG			0x08
#define PHYCNT_SHUTDOWNZ		(1 << 17)
#define PHYCNT_RSTZ			(1 << 16)
#define PHYCNT_ENABLECLK		(1 << 4)
#define PHYCNT_ENABLE_3			(1 << 3)
#define PHYCNT_ENABLE_2			(1 << 2)
#define PHYCNT_ENABLE_1			(1 << 1)
#define PHYCNT_ENABLE_0			(1 << 0)

/* Checksum Control */
#define CHKSUM_REG			0x0c
#define CHKSUM_ECC_EN			(1 << 1)
#define CHKSUM_CRC_EN			(1 << 0)

/*
 * Channel Data Type Select
 * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
 * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
 */
#define VCDT_REG			0x10
#define VCDT2_REG			0x14
#define VCDT_VCDTN_EN			(1 << 15)
#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
#define VCDT_SEL_DTN_ON			(1 << 6)
#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)

/* Frame Data Type Select */
#define FRDT_REG			0x18

/* Field Detection Control */
#define FLD_REG				0x1c
#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
#define FLD_FLD_EN4			(1 << 3)
#define FLD_FLD_EN3			(1 << 2)
#define FLD_FLD_EN2			(1 << 1)
#define FLD_FLD_EN			(1 << 0)

/* Automatic Standby Control */
#define ASTBY_REG			0x20

/* Long Data Type Setting 0 */
#define LNGDT0_REG			0x28

/* Long Data Type Setting 1 */
#define LNGDT1_REG			0x2c

/* Interrupt Enable */
#define INTEN_REG			0x30

/* Interrupt Source Mask */
#define INTCLOSE_REG			0x34

/* Interrupt Status Monitor */
#define INTSTATE_REG			0x38

/* Interrupt Error Status Monitor */
#define INTERRSTATE_REG			0x3c

/* Short Packet Data */
#define SHPDAT_REG			0x40

/* Short Packet Count */
#define SHPCNT_REG			0x44

/* LINK Operation Control */
#define LINKCNT_REG			0x48
#define LINKCNT_MONITOR_EN		(1 << 31)
#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
#define LINKCNT_ICLK_NONSTOP		(1 << 24)

/* Lane Swap */
#define LSWAP_REG			0x4c
#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)

/* PHY Test Interface Clear */
#define PHTC_REG			0x58
#define PHTC_TESTCLR			(1 << 0)

/* PHY Frequency Control */
#define PHYPLL_REG			0x68
#define PHYPLL_HSFREQRANGE(n)		((n) << 16)

struct phypll_hsfreqrange {
	unsigned int	mbps;
	unsigned char	reg;
};

static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
	{ .mbps =   80,	.reg = 0x00 },
	{ .mbps =   90,	.reg = 0x10 },
	{ .mbps =  100,	.reg = 0x20 },
	{ .mbps =  110,	.reg = 0x30 },
	{ .mbps =  120,	.reg = 0x01 },
	{ .mbps =  130,	.reg = 0x11 },
	{ .mbps =  140,	.reg = 0x21 },
	{ .mbps =  150,	.reg = 0x31 },
	{ .mbps =  160,	.reg = 0x02 },
	{ .mbps =  170,	.reg = 0x12 },
	{ .mbps =  180,	.reg = 0x22 },
	{ .mbps =  190,	.reg = 0x32 },
	{ .mbps =  205,	.reg = 0x03 },
	{ .mbps =  220,	.reg = 0x13 },
	{ .mbps =  235,	.reg = 0x23 },
	{ .mbps =  250,	.reg = 0x33 },
	{ .mbps =  275,	.reg = 0x04 },
	{ .mbps =  300,	.reg = 0x14 },
	{ .mbps =  325,	.reg = 0x05 },
	{ .mbps =  350,	.reg = 0x15 },
	{ .mbps =  400,	.reg = 0x25 },
	{ .mbps =  450,	.reg = 0x06 },
	{ .mbps =  500,	.reg = 0x16 },
	{ .mbps =  550,	.reg = 0x07 },
	{ .mbps =  600,	.reg = 0x17 },
	{ .mbps =  650,	.reg = 0x08 },
	{ .mbps =  700,	.reg = 0x18 },
	{ .mbps =  750,	.reg = 0x09 },
	{ .mbps =  800,	.reg = 0x19 },
	{ .mbps =  850,	.reg = 0x29 },
	{ .mbps =  900,	.reg = 0x39 },
	{ .mbps =  950,	.reg = 0x0A },
	{ .mbps = 1000,	.reg = 0x1A },
	{ .mbps = 1050,	.reg = 0x2A },
	{ .mbps = 1100,	.reg = 0x3A },
	{ .mbps = 1150,	.reg = 0x0B },
	{ .mbps = 1200,	.reg = 0x1B },
	{ .mbps = 1250,	.reg = 0x2B },
	{ .mbps = 1300,	.reg = 0x3B },
	{ .mbps = 1350,	.reg = 0x0C },
	{ .mbps = 1400,	.reg = 0x1C },
	{ .mbps = 1450,	.reg = 0x2C },
	{ .mbps = 1500,	.reg = 0x3C },
	/* guard */
	{ .mbps =   0,	.reg = 0x00 },
};

/* PHY ESC Error Monitor */
#define PHEERM_REG			0x74

/* PHY Clock Lane Monitor */
#define PHCLM_REG			0x78

/* PHY Data Lane Monitor */
#define PHDLM_REG			0x7c

struct rcar_csi2_format {
	unsigned int code;
	unsigned int datatype;
	unsigned int bpp;
};

static const struct rcar_csi2_format rcar_csi2_formats[] = {
	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
};

static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
		if (rcar_csi2_formats[i].code == code)
			return rcar_csi2_formats + i;
	return NULL;
}

enum rcar_csi2_pads {
	RCAR_CSI2_SINK,
	RCAR_CSI2_SOURCE_VC0,
	RCAR_CSI2_SOURCE_VC1,
	RCAR_CSI2_SOURCE_VC2,
	RCAR_CSI2_SOURCE_VC3,
	NR_OF_RCAR_CSI2_PAD,
};

struct rcar_csi2 {
	struct device *dev;
	void __iomem *base;

	unsigned short lanes;
	unsigned char lane_swap[4];

	struct v4l2_subdev subdev;
	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];

	struct v4l2_mbus_framefmt mf;

	struct mutex lock;
	int stream_count;

	struct v4l2_async_notifier notifier;
	struct {
		struct v4l2_async_subdev asd;
		struct v4l2_subdev *subdev;
		struct fwnode_handle *fwnode;
		unsigned int source_pad;
	} remote;
};

static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
{
	return container_of(sd, struct rcar_csi2, subdev);
}

static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
{
	return ioread32(priv->base + reg);
}

static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
{
	iowrite32(data, priv->base + reg);
}

static void rcar_csi2_reset(struct rcar_csi2 *priv)
{
	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
	rcar_csi2_write(priv, SRST_REG, 0);
}

static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
{
	int timeout;

	/* Wait for the clock and data lanes to enter LP-11 state. */
	for (timeout = 100; timeout >= 0; timeout--) {
		const u32 lane_mask = (1 << priv->lanes) - 1;

		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
			return 0;

		msleep(20);
	}

	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");

	return -ETIMEDOUT;
}

static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
				 struct v4l2_subdev *source,
				 struct v4l2_mbus_framefmt *mf,
				 u32 *phypll)
{
	const struct phypll_hsfreqrange *hsfreq;
	const struct rcar_csi2_format *format;
	struct v4l2_ext_controls ctrls;
	struct v4l2_ext_control ctrl;
	u64 mbps;
	int ret;

	memset(&ctrls, 0, sizeof(ctrls));
	memset(&ctrl, 0, sizeof(ctrl));

	ctrl.id = V4L2_CID_PIXEL_RATE;

	ctrls.count = 1;
	ctrls.controls = &ctrl;

	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);
	if (ret < 0) {
		dev_err(priv->dev, "no link freq control in subdev %s\n",
			source->name);
		return ret;
	}

	format = rcar_csi2_code_to_fmt(mf->code);
	if (!format) {
		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
		return -EINVAL;
	}

	mbps = ctrl.value64 * format->bpp;
	do_div(mbps, priv->lanes * 1000000);

	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
		if (hsfreq->mbps >= mbps)
			break;

	if (!hsfreq->mbps) {
		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
		return -ERANGE;
	}

	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
		hsfreq->mbps);

	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);

	return 0;
}

static int rcar_csi2_start(struct rcar_csi2 *priv)
{
	const struct rcar_csi2_format *format;
	struct v4l2_subdev_format fmt;
	struct media_pad *source_pad;
	struct v4l2_subdev *source = NULL;
	struct v4l2_mbus_framefmt *mf = &fmt.format;
	u32 phycnt, phypll, tmp;
	u32 vcdt = 0, vcdt2 = 0;
	unsigned int i;
	int ret;

	source_pad =
		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);
	if (!source_pad) {
		dev_err(priv->dev, "Could not find remote source pad\n");
		return -ENODEV;
	}

	source = media_entity_to_v4l2_subdev(source_pad->entity);
	if (!source) {
		dev_err(priv->dev, "Could not find remote subdevice\n");
		return -ENODEV;
	}

	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
		source_pad->index);

	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
	fmt.pad = source_pad->index;
	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
	if (ret)
		return ret;

	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');

	/*
	 * Enable all Virtual Channels
	 *
	 * NOTE: I'ts not possible to get individual format for each
	 *       source virtual channel. Once this is possible in V4L2
	 *       it should be used here.
	 */
	for (i = 0; i < 4; i++) {

		format = rcar_csi2_code_to_fmt(mf->code);
		if (!format) {
			dev_err(priv->dev, "Unsupported media bus format: %d\n",
				mf->code);
			return -EINVAL;
		}

		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
			VCDT_SEL_DT(format->datatype);

		/* Store in correct reg and offset */
		if (i < 2)
			vcdt |= tmp << ((i % 2) * 16);
		else
			vcdt2 |= tmp << ((i % 2) * 16);
	}

	switch (priv->lanes) {
	case 1:
		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
		break;
	case 2:
		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
		break;
	case 4:
		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
		break;
	default:
		return -EINVAL;
	}

	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
	if (ret)
		return ret;

	/* Init */
	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
	rcar_csi2_reset(priv);
	rcar_csi2_write(priv, PHTC_REG, 0);

	/* Configure */
	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
	rcar_csi2_write(priv, VCDT_REG, vcdt);
	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
	/* Lanes are zero indexed */
	rcar_csi2_write(priv, LSWAP_REG,
			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
			LSWAP_L3SEL(priv->lane_swap[3] - 1));

	/* Start */
	rcar_csi2_write(priv, PHYPLL_REG, phypll);
	rcar_csi2_write(priv, PHYCNT_REG, phycnt);
	rcar_csi2_write(priv, LINKCNT_REG, LINKCNT_MONITOR_EN |
			LINKCNT_REG_MONI_PACT_EN | LINKCNT_ICLK_NONSTOP);
	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ);
	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ |
			PHYCNT_RSTZ);

	return rcar_csi2_wait_phy_start(priv);
}

static void rcar_csi2_stop(struct rcar_csi2 *priv)
{
	rcar_csi2_write(priv, PHYCNT_REG, 0);

	rcar_csi2_reset(priv);
}

static int rcar_csi2_sd_info(struct rcar_csi2 *priv, struct v4l2_subdev **sd)
{
	struct media_pad *pad;

	pad = media_entity_remote_pad(&priv->pads[RCAR_CSI2_SINK]);
	if (!pad) {
		dev_err(priv->dev, "Could not find remote pad\n");
		return -ENODEV;
	}

	*sd = media_entity_to_v4l2_subdev(pad->entity);
	if (!*sd) {
		dev_err(priv->dev, "Could not find remote subdevice\n");
		return -ENODEV;
	}

	return 0;
}

static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
{
	struct rcar_csi2 *priv = sd_to_csi2(sd);
	struct v4l2_subdev *nextsd;
	int ret;

	mutex_lock(&priv->lock);

	ret = rcar_csi2_sd_info(priv, &nextsd);
	if (ret)
		goto out;

	priv->stream_count += enable ? 1 : -1;

	if (enable && priv->stream_count == 1) {
		ret =  rcar_csi2_start(priv);
		if (ret)
			goto out;
		ret = v4l2_subdev_call(nextsd, video, s_stream, 1);

	} else if (!enable && !priv->stream_count) {
		rcar_csi2_stop(priv);
		ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
	}
out:
	mutex_unlock(&priv->lock);

	return ret;
}

static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
{
	struct rcar_csi2 *priv = sd_to_csi2(sd);

	if (on)
		pm_runtime_get_sync(priv->dev);
	else
		pm_runtime_put(priv->dev);

	return 0;
}

static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
				    struct v4l2_subdev_pad_config *cfg,
				    struct v4l2_subdev_format *format)
{
	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);

	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
		priv->mf = format->format;

	return 0;
}

static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
				    struct v4l2_subdev_pad_config *cfg,
				    struct v4l2_subdev_format *format)
{
	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);

	format->format = priv->mf;

	return 0;
}

static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
	.s_stream = rcar_csi2_s_stream,
};

static const struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
	.s_power = rcar_csi2_s_power,
};

static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
	.set_fmt = rcar_csi2_set_pad_format,
	.get_fmt = rcar_csi2_get_pad_format,
};

static const struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
	.video	= &rcar_csi2_video_ops,
	.core	= &rcar_csi2_subdev_core_ops,
	.pad	= &rcar_csi2_pad_ops,
};

/* -----------------------------------------------------------------------------
 * Async and registered of subdevices and links
 */

#define notifier_to_priv(n) container_of(n, struct rcar_csi2, notifier)

static int rcar_csi2_notify_complete(struct v4l2_async_notifier *notifier)
{
	struct rcar_csi2 *priv = notifier_to_priv(notifier);
	int ret;

	ret = v4l2_device_register_subdev_nodes(priv->subdev.v4l2_dev);
	if (ret) {
		dev_err(priv->dev, "Failed to register subdev nodes\n");
		return ret;
	}

	return media_create_pad_link(&priv->remote.subdev->entity,
				     priv->remote.source_pad,
				     &priv->subdev.entity, 0,
				     MEDIA_LNK_FL_ENABLED |
				     MEDIA_LNK_FL_IMMUTABLE);
}

static int rcar_csi2_notify_bound(struct v4l2_async_notifier *notifier,
				   struct v4l2_subdev *subdev,
				   struct v4l2_async_subdev *asd)
{
	struct rcar_csi2 *priv = notifier_to_priv(notifier);
	int ret;

	v4l2_set_subdev_hostdata(subdev, priv);

	ret = media_entity_pad_from_fwnode(&subdev->entity,
					   priv->remote.fwnode,
					   MEDIA_PAD_FL_SOURCE,
					   &priv->remote.source_pad);
	if (ret) {
		dev_err(priv->dev, "Failed to find pad for %s\n",
			subdev->name);
		return ret;
	}

	dev_dbg(priv->dev, "Bound %s pad: %d\n", subdev->name,
		priv->remote.source_pad);
	priv->remote.subdev = subdev;

	return 0;
}
static void rcar_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
				     struct v4l2_subdev *subdev,
				     struct v4l2_async_subdev *asd)
{
	struct rcar_csi2 *priv = notifier_to_priv(notifier);

	dev_dbg(priv->dev, "Unbind %s\n", subdev->name);
	priv->remote.subdev = NULL;
}

static int rcar_csi2_registered(struct v4l2_subdev *sd)
{
	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
	struct v4l2_async_subdev **subdevs = NULL;
	int ret;

	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
	if (subdevs == NULL)
		return -ENOMEM;

	subdevs[0] = &priv->remote.asd;

	priv->notifier.num_subdevs = 1;
	priv->notifier.subdevs = subdevs;
	priv->notifier.bound = rcar_csi2_notify_bound;
	priv->notifier.unbind = rcar_csi2_notify_unbind;
	priv->notifier.complete = rcar_csi2_notify_complete;

	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
	if (ret < 0) {
		dev_err(priv->dev, "Notifier registration failed\n");
		return ret;
	}

	return 0;
}

static void rcar_csi2_unregistered(struct v4l2_subdev *sd)
{
	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);

	v4l2_async_subnotifier_unregister(&priv->notifier);
}

static const struct v4l2_subdev_internal_ops rcar_csi2_internal_ops = {
	.registered = rcar_csi2_registered,
	.unregistered = rcar_csi2_unregistered,
};

static int rcar_csi2_parse_dt_subdevice(struct rcar_csi2 *priv)
{
	struct device_node *remote, *ep;
	struct v4l2_fwnode_endpoint v4l2_ep;
	int ret;

	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
	if (!ep) {
		dev_err(priv->dev, "Not connected to subdevice\n");
		return -EINVAL;
	}

	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
	if (ret) {
		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
		of_node_put(ep);
		return -EINVAL;
	}

	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
		dev_err(priv->dev, "Unknown media bus type: 0x%x\n",
			v4l2_ep.bus_type);
		of_node_put(ep);
		return -EINVAL;
	}

	priv->remote.fwnode =
		fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));

	remote = of_graph_get_remote_port_parent(ep);
	of_node_put(ep);
	if (!remote) {
		dev_err(priv->dev, "No subdevice found for endpoint '%s'\n",
			of_node_full_name(ep));
		return -EINVAL;
	}

	priv->remote.asd.match.fwnode.fwnode = of_fwnode_handle(remote);
	priv->remote.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;

	dev_dbg(priv->dev, "Found '%s'\n", of_node_full_name(remote));

	return 0;
}

/* -----------------------------------------------------------------------------
 * Platform Device Driver
 */

static const struct of_device_id rcar_csi2_of_table[] = {
	{ .compatible = "renesas,rcar-gen3-csi2" },
	{ },
};
MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);

static const struct media_entity_operations rcar_csi2_entity_ops = {
	.link_validate = v4l2_subdev_link_validate,
};

static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
{
	struct v4l2_fwnode_endpoint v4l2_ep;
	struct device_node *ep;
	unsigned int i;
	int ret;

	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
	if (!ep)
		return -EINVAL;

	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
	of_node_put(ep);
	if (ret) {
		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
		return -EINVAL;
	}

	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
		dev_err(priv->dev, "Unsupported media bus type for %s\n",
			of_node_full_name(ep));
		return -EINVAL;
	}

	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
			priv->lanes);
		return -EINVAL;
	}

	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
		priv->lane_swap[i] = i < priv->lanes ?
			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;

		/* Check for valid lane number */
		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {
			dev_err(priv->dev, "data-lanes must be in 1-4 range\n");
			return -EINVAL;
		}
	}

	return 0;
}

static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
				     struct platform_device *pdev)
{
	struct resource *mem;
	int irq;

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem)
		return -ENODEV;

	priv->base = devm_ioremap_resource(&pdev->dev, mem);
	if (IS_ERR(priv->base))
		return PTR_ERR(priv->base);

	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
		return irq;

	return 0;
}

static int rcar_csi2_probe(struct platform_device *pdev)
{
	struct rcar_csi2 *priv;
	unsigned int i;
	int ret;

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

	priv->dev = &pdev->dev;

	mutex_init(&priv->lock);
	priv->stream_count = 0;

	ret = rcar_csi2_parse_dt_settings(priv);
	if (ret)
		return ret;

	ret = rcar_csi2_parse_dt_subdevice(priv);
	if (ret)
		return ret;

	ret = rcar_csi2_probe_resources(priv, pdev);
	if (ret) {
		dev_err(priv->dev, "Failed to get resources\n");
		return ret;
	}

	platform_set_drvdata(pdev, priv);

	priv->subdev.owner = THIS_MODULE;
	priv->subdev.dev = &pdev->dev;
	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
		 KBUILD_MODNAME, dev_name(&pdev->dev));
	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
	priv->subdev.internal_ops = &rcar_csi2_internal_ops;

	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
	priv->subdev.entity.ops = &rcar_csi2_entity_ops;

	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
	for (i = RCAR_CSI2_SOURCE_VC0; i < NR_OF_RCAR_CSI2_PAD; i++)
		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;

	ret = media_entity_pads_init(&priv->subdev.entity, NR_OF_RCAR_CSI2_PAD,
				     priv->pads);
	if (ret)
		return ret;

	ret = v4l2_async_register_subdev(&priv->subdev);
	if (ret < 0)
		return ret;

	pm_runtime_enable(&pdev->dev);

	dev_info(priv->dev, "%d lanes found\n", priv->lanes);

	return 0;
}

static int rcar_csi2_remove(struct platform_device *pdev)
{
	struct rcar_csi2 *priv = platform_get_drvdata(pdev);

	v4l2_async_unregister_subdev(&priv->subdev);

	pm_runtime_disable(&pdev->dev);

	return 0;
}

static struct platform_driver __refdata rcar_csi2_pdrv = {
	.remove	= rcar_csi2_remove,
	.probe	= rcar_csi2_probe,
	.driver	= {
		.name	= "rcar-csi2",
		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
	},
};

module_platform_driver(rcar_csi2_pdrv);

MODULE_AUTHOR("Niklas Söderlund <niklas.soderlund@ragnatech.se>");
MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 receiver");
MODULE_LICENSE("GPL v2");