Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

["Niklas Söderlund" <niklas.soderlund@ragnatech.se>]

Hi Sakari,

Thanks for your comments.

On 2017-05-29 14:35:16 +0300, Sakari Ailus wrote:
> Hi Niklas,
> 
> A few comments below.
> 
> On Wed, May 24, 2017 at 02:13:53AM +0200, Niklas Söderlund wrote:
> > From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > 
> > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > hardware blocks are connected between the video sources and the video
> > grabbers (VIN).
> > 
> > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > 
> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >  drivers/media/platform/rcar-vin/Kconfig     |  12 +
> >  drivers/media/platform/rcar-vin/Makefile    |   1 +
> >  drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> >  3 files changed, 880 insertions(+)
> >  create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > 
> > diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> > index af4c98b44d2e22cb..6875f30c1ae42631 100644
> > --- a/drivers/media/platform/rcar-vin/Kconfig
> > +++ b/drivers/media/platform/rcar-vin/Kconfig
> > @@ -1,3 +1,15 @@
> > +config VIDEO_RCAR_CSI2
> > +	tristate "R-Car MIPI CSI-2 Receiver"
> > +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> > +	depends on ARCH_RENESAS || COMPILE_TEST
> > +	select V4L2_FWNODE
> > +	---help---
> > +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> > +	  Supports R-Car Gen3 SoCs.
> > +
> > +	  To compile this driver as a module, choose M here: the
> > +	  module will be called rcar-csi2.
> > +
> >  config VIDEO_RCAR_VIN
> >  	tristate "R-Car Video Input (VIN) Driver"
> >  	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> > diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> > index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> > --- a/drivers/media/platform/rcar-vin/Makefile
> > +++ b/drivers/media/platform/rcar-vin/Makefile
> > @@ -1,3 +1,4 @@
> >  rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
> >  
> > +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
> >  obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > new file mode 100644
> > index 0000000000000000..1175f1fe4b139a13
> > --- /dev/null
> > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > @@ -0,0 +1,867 @@
> > +/*
> > + * 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);
> 
> v4l2_ctrl_g_ctrl_int64(), please. Or do I miss something?

Thanks will fix.

> 
> > +	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]);
> 
> Over 80 characters per line. I think you could split this up differently.

Will fix.

> 
> > +	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
> 
> "It's"

Ops.. will fix :-)

> 
> > +	 *       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));
> 
> How are the lanes numbered?

In the datasheet they are numbered CSIn_DATA{0,1,2,3}.

> 
> Do you have a fixed number of lanes per receiver?

Two different configurations exists a 4-lane CSI-2 receiver and a 2-lane 
CSI-2 receiver.

> 
> > +
> > +	/* 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;
> 
> How about the try formats? E.g.
> 
> *v4l2_subdev_get_try_format() = format->fmt;

Thanks will fix.

> 
> > +
> > +	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;
> 
> Ditto.

Ditto :-)

> 
> > +
> > +	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;
> > +}
> 
> A newline would be nice here.

Yes.

> 
> > +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) {
> 
> Do you also support for three lanes? Based on the code elsewhere, it doesn't
> seem like that.

Yes 3-lanes should be supported but I have no way of testing this. But I 
do belive the code is prepared to handle it, see for example in the 
driver all logic around priv->lanes variable, am I missing something?

> 
> > +			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");
> 
> -- 
> Regards,
> 
> Sakari Ailus
> e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

-- 
Regards,
Niklas Söderlund