Re: [PATCH v10 2/2] media: v4l: xilinx: Add Xilinx MIPI CSI-2 Rx Subsystem driver

[Sakari Ailus <sakari.ailus@iki.fi>]

Hi Vishal,

Thanks for the update.

On Thu, Jul 11, 2019 at 02:46:12PM +0530, Vishal Sagar wrote:
> The Xilinx MIPI CSI-2 Rx Subsystem soft IP is used to capture images
> from MIPI CSI-2 camera sensors and output AXI4-Stream video data ready
> for image processing. Please refer to PG232 for details.
> 
> The CSI2 Rx controller filters out all packets except for the packets
> with data type fixed in hardware. RAW8 packets are always allowed to
> pass through.
> 
> It is also used to setup and handle interrupts and enable the core. It
> logs all the events in respective counters between streaming on and off.
> 
> The driver supports only the video format bridge enabled configuration.
> Some data types like YUV 422 10bpc, RAW16, RAW20 are supported when the
> CSI v2.0 feature is enabled in design. When the VCX feature is enabled,
> the maximum number of virtual channels becomes 16 from 4.
> 
> Signed-off-by: Vishal Sagar <vishal.sagar@xilinx.com>
> Reviewed-by: Hyun Kwon <hyun.kwon@xilinx.com>
> ---
> v10
> - Removed all V4L2 controls and events based on Sakari's comments.
> - Now stop_stream() before toggling rst_gpio
> - Updated init_mbus() to throw error on array out of bound access
> - Make events and vcx_events as counters instead of structures
> - Minor fixes in set_format() enum_mbus_code() as suggested by Sakari
> 
> v9
> - Moved all controls and events to xilinx-csi2rxss.h
> - Updated name and description of controls and events
> - Get control base address from v4l2-controls.h (0x10c0)
> - Fix KConfig for dependency on VIDEO_XILINX
> - Added enum_mbus_code() support
> - Added default format to be returned on open()
> - Mark variables are const
> - Remove references to short packet in comments
> - Add check for streaming before setting active lanes control
> - strlcpy -> strscpy
> - Fix xcsi2rxss_set_format()
> 
> v8
> - Use clk_bulk* APIs
> - Add gpio reset for asserting video_aresetn when stream line buffer occurs
> - Removed short packet related events and irq handling
>   - V4L2_EVENT_XLNXCSIRX_SPKT and V4L2_EVENT_XLNXCSIRX_SPKT_OVF removed
> - Removed frame counter control V4L2_CID_XILINX_MIPICSISS_FRAME_COUNTER
>   and xcsi2rxss_g_volatile_ctrl()
> - Minor formatting fixes
> 
> v7
> - No change
> 
> v6
> - No change
> 
> v5
> - Removed bayer and updated related parts like set default format based
>   on Luca Cersoli's comments.
> - Added correct YUV422 10bpc media bus format
> 
> v4
> - Removed irq member from core structure
> - Consolidated IP config prints in xcsi2rxss_log_ipconfig()
> - Return -EINVAL in case of invalid ioctl
> - Code formatting
> - Added reviewed by Hyun Kwon
> 
> v3
> - Fixed comments given by Hyun.
> - Removed DPHY 200 MHz clock. This will be controlled by DPHY driver
> - Minor code formatting
> - en_csi_v20 and vfb members removed from struct and made local to dt parsing
> - lock description updated
> - changed to ratelimited type for all dev prints in irq handler
> - Removed YUV 422 10bpc media format
> 
> v2
> - Fixed comments given by Hyun and Sakari.
> - Made all bitmask using BIT() and GENMASK()
> - Removed unused definitions
> - Removed DPHY access. This will be done by separate DPHY PHY driver.
> - Added support for CSI v2.0 for YUV 422 10bpc, RAW16, RAW20 and extra
>   virtual channels
> - Fixed the ports as sink and source
> - Now use the v4l2fwnode API to get number of data-lanes
> - Added clock framework support
> - Removed the close() function
> - updated the set format function
> - support only VFB enabled configuration
>  drivers/media/platform/xilinx/Kconfig         |   11 +
>  drivers/media/platform/xilinx/Makefile        |    1 +
>  .../media/platform/xilinx/xilinx-csi2rxss.c   | 1230 +++++++++++++++++
>  3 files changed, 1242 insertions(+)
>  create mode 100644 drivers/media/platform/xilinx/xilinx-csi2rxss.c
> 
> diff --git a/drivers/media/platform/xilinx/Kconfig b/drivers/media/platform/xilinx/Kconfig
> index a2773ad7c185..349da877c846 100644
> --- a/drivers/media/platform/xilinx/Kconfig
> +++ b/drivers/media/platform/xilinx/Kconfig
> @@ -10,6 +10,17 @@ config VIDEO_XILINX
>  
>  if VIDEO_XILINX
>  
> +config VIDEO_XILINX_CSI2RXSS
> +	tristate "Xilinx CSI2 Rx Subsystem"
> +	depends on VIDEO_XILINX

You don't need to depend on VIDEO_XILINX here due to the condition above.

> +	help
> +	  Driver for Xilinx MIPI CSI2 Rx Subsystem. This is a V4L sub-device
> +	  based driver that takes input from CSI2 Tx source and converts
> +	  it into an AXI4-Stream. The subsystem comprises of a CSI2 Rx
> +	  controller, DPHY, an optional I2C controller and a Video Format
> +	  Bridge. The driver is used to set the number of active lanes and
> +	  get short packet data.
> +
>  config VIDEO_XILINX_TPG
>  	tristate "Xilinx Video Test Pattern Generator"
>  	depends on VIDEO_XILINX
> diff --git a/drivers/media/platform/xilinx/Makefile b/drivers/media/platform/xilinx/Makefile
> index 4cdc0b1ec7a5..6119a34f3043 100644
> --- a/drivers/media/platform/xilinx/Makefile
> +++ b/drivers/media/platform/xilinx/Makefile
> @@ -3,5 +3,6 @@
>  xilinx-video-objs += xilinx-dma.o xilinx-vip.o xilinx-vipp.o
>  
>  obj-$(CONFIG_VIDEO_XILINX) += xilinx-video.o
> +obj-$(CONFIG_VIDEO_XILINX_CSI2RXSS) += xilinx-csi2rxss.o
>  obj-$(CONFIG_VIDEO_XILINX_TPG) += xilinx-tpg.o
>  obj-$(CONFIG_VIDEO_XILINX_VTC) += xilinx-vtc.o
> diff --git a/drivers/media/platform/xilinx/xilinx-csi2rxss.c b/drivers/media/platform/xilinx/xilinx-csi2rxss.c
> new file mode 100644
> index 000000000000..1a22ca80382e
> --- /dev/null
> +++ b/drivers/media/platform/xilinx/xilinx-csi2rxss.c
> @@ -0,0 +1,1230 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Driver for Xilinx MIPI CSI2 Rx Subsystem
> + *
> + * Copyright (C) 2016 - 2019 Xilinx, Inc.
> + *
> + * Contacts: Vishal Sagar <vishal.sagar@xilinx.com>
> + *
> + */
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/of.h>
> +#include <linux/of_irq.h>
> +#include <linux/platform_device.h>
> +#include <linux/v4l2-subdev.h>
> +#include <media/media-entity.h>
> +#include <media/v4l2-common.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-subdev.h>
> +#include "xilinx-vip.h"
> +
> +/* Register register map */
> +#define XCSI_CCR_OFFSET		0x00
> +#define XCSI_CCR_SOFTRESET	BIT(1)
> +#define XCSI_CCR_ENABLE		BIT(0)
> +
> +#define XCSI_PCR_OFFSET		0x04
> +#define XCSI_PCR_MAXLANES_MASK	GENMASK(4, 3)
> +#define XCSI_PCR_ACTLANES_MASK	GENMASK(1, 0)
> +
> +#define XCSI_CSR_OFFSET		0x10
> +#define XCSI_CSR_PKTCNT		GENMASK(31, 16)
> +#define XCSI_CSR_SPFIFOFULL	BIT(3)
> +#define XCSI_CSR_SPFIFONE	BIT(2)
> +#define XCSI_CSR_SLBF		BIT(1)
> +#define XCSI_CSR_RIPCD		BIT(0)
> +
> +#define XCSI_GIER_OFFSET	0x20
> +#define XCSI_GIER_GIE		BIT(0)
> +
> +#define XCSI_ISR_OFFSET		0x24
> +#define XCSI_IER_OFFSET		0x28
> +
> +#define XCSI_ISR_FR		BIT(31)
> +#define XCSI_ISR_VCXFE		BIT(30)
> +#define XCSI_ISR_WCC		BIT(22)
> +#define XCSI_ISR_ILC		BIT(21)
> +#define XCSI_ISR_SPFIFOF	BIT(20)
> +#define XCSI_ISR_SPFIFONE	BIT(19)
> +#define XCSI_ISR_SLBF		BIT(18)
> +#define XCSI_ISR_STOP		BIT(17)
> +#define XCSI_ISR_SOTERR		BIT(13)
> +#define XCSI_ISR_SOTSYNCERR	BIT(12)
> +#define XCSI_ISR_ECC2BERR	BIT(11)
> +#define XCSI_ISR_ECC1BERR	BIT(10)
> +#define XCSI_ISR_CRCERR		BIT(9)
> +#define XCSI_ISR_DATAIDERR	BIT(8)
> +#define XCSI_ISR_VC3FSYNCERR	BIT(7)
> +#define XCSI_ISR_VC3FLVLERR	BIT(6)
> +#define XCSI_ISR_VC2FSYNCERR	BIT(5)
> +#define XCSI_ISR_VC2FLVLERR	BIT(4)
> +#define XCSI_ISR_VC1FSYNCERR	BIT(3)
> +#define XCSI_ISR_VC1FLVLERR	BIT(2)
> +#define XCSI_ISR_VC0FSYNCERR	BIT(1)
> +#define XCSI_ISR_VC0FLVLERR	BIT(0)
> +
> +#define XCSI_INTR_PROT_MASK	(XCSI_ISR_VC3FSYNCERR |	XCSI_ISR_VC3FLVLERR |\
> +				 XCSI_ISR_VC2FSYNCERR | XCSI_ISR_VC2FLVLERR |\
> +				 XCSI_ISR_VC1FSYNCERR | XCSI_ISR_VC1FLVLERR |\
> +				 XCSI_ISR_VC0FSYNCERR |	XCSI_ISR_VC0FLVLERR |\
> +				 XCSI_ISR_VCXFE)
> +
> +#define XCSI_INTR_PKTLVL_MASK	(XCSI_ISR_ECC2BERR | XCSI_ISR_ECC1BERR |\
> +				 XCSI_ISR_CRCERR | XCSI_ISR_DATAIDERR)
> +
> +#define XCSI_INTR_DPHY_MASK	(XCSI_ISR_SOTERR | XCSI_ISR_SOTSYNCERR)
> +
> +#define XCSI_INTR_SPKT_MASK	(XCSI_ISR_SPFIFOF | XCSI_ISR_SPFIFONE)
> +
> +#define XCSI_INTR_ERR_MASK	(XCSI_ISR_WCC | XCSI_ISR_ILC | XCSI_ISR_SLBF |\
> +				 XCSI_ISR_STOP)
> +
> +#define XCSI_INTR_FRAMERCVD_MASK	(XCSI_ISR_FR)
> +
> +#define XCSI_ISR_ALLINTR_MASK	(XCSI_INTR_PROT_MASK | XCSI_INTR_PKTLVL_MASK |\
> +				 XCSI_INTR_DPHY_MASK | XCSI_INTR_SPKT_MASK |\
> +				 XCSI_INTR_ERR_MASK | XCSI_INTR_FRAMERCVD_MASK)
> +
> +/*
> + * Removed VCXFE mask as it doesn't exist in IER
> + * Removed STOP state irq as this will keep driver in irq handler only
> + */
> +#define XCSI_IER_INTR_MASK	(XCSI_ISR_ALLINTR_MASK &\
> +				 ~(XCSI_ISR_STOP | XCSI_ISR_VCXFE))
> +
> +#define XCSI_SPKTR_OFFSET	0x30
> +#define XCSI_SPKTR_DATA		GENMASK(23, 8)
> +#define XCSI_SPKTR_VC		GENMASK(7, 6)
> +#define XCSI_SPKTR_DT		GENMASK(5, 0)
> +
> +#define XCSI_VCXR_OFFSET	0x34
> +#define XCSI_VCXR_VCERR		GENMASK(23, 0)
> +#define XCSI_VCXR_VCSTART	4
> +#define XCSI_VCXR_VCEND		15
> +#define XCSI_VCXR_FSYNCERR	BIT(1)
> +#define XCSI_VCXR_FLVLERR	BIT(0)
> +
> +#define XCSI_CLKINFR_OFFSET	0x3C
> +#define XCSI_CLKINFR_STOP	BIT(1)
> +
> +#define XCSI_DLXINFR_OFFSET	0x40
> +#define XCSI_DLXINFR_STOP	BIT(5)
> +#define XCSI_DLXINFR_SOTERR	BIT(1)
> +#define XCSI_DLXINFR_SOTSYNCERR	BIT(0)
> +#define XCSI_MAXDL_COUNT	0x4
> +
> +#define XCSI_VCXINF1R_OFFSET		0x60
> +#define XCSI_VCXINF1R_LINECOUNT		GENMASK(31, 16)
> +#define XCSI_VCXINF1R_LINECOUNT_SHIFT	16
> +#define XCSI_VCXINF1R_BYTECOUNT		GENMASK(15, 0)
> +
> +#define XCSI_VCXINF2R_OFFSET	0x64
> +#define XCSI_VCXINF2R_DT	GENMASK(5, 0)
> +#define XCSI_MAXVCX_COUNT	16
> +
> +/*
> + * The core takes less than 100 video clock cycles to reset.
> + * So choosing a timeout value larger than this.
> + */
> +#define XCSI_TIMEOUT_VAL	1000 /* us */
> +
> +/*
> + * Sink pad connected to sensor source pad.
> + * Source pad connected to next module like demosaic.
> + */
> +#define XCSI_MEDIA_PADS		2
> +#define XCSI_DEFAULT_WIDTH	1920
> +#define XCSI_DEFAULT_HEIGHT	1080
> +
> +/* Max media bus formats supported for enumeration */
> +#define XCSI_MAX_MBUS_FMTS	16
> +
> +/* Max string length for CSI Data type string */
> +#define XCSI_PXLFMT_STRLEN_MAX	16
> +
> +/* MIPI CSI2 Data Types from spec */
> +#define XCSI_DT_YUV4228B	0x1E
> +#define XCSI_DT_YUV42210B	0x1F
> +#define XCSI_DT_RGB444		0x20
> +#define XCSI_DT_RGB555		0x21
> +#define XCSI_DT_RGB565		0x22
> +#define XCSI_DT_RGB666		0x23
> +#define XCSI_DT_RGB888		0x24
> +#define XCSI_DT_RAW6		0x28
> +#define XCSI_DT_RAW7		0x29
> +#define XCSI_DT_RAW8		0x2A
> +#define XCSI_DT_RAW10		0x2B
> +#define XCSI_DT_RAW12		0x2C
> +#define XCSI_DT_RAW14		0x2D
> +#define XCSI_DT_RAW16		0x2E
> +#define XCSI_DT_RAW20		0x2F
> +
> +#define XCSI_VCX_START		4
> +#define XCSI_MAX_VC		4
> +#define XCSI_MAX_VCX		16
> +
> +#define XCSI_NEXTREG_OFFSET	4
> +
> +/* There are 2 events frame sync and frame level error per VC */
> +#define XCSI_VCX_NUM_EVENTS	((XCSI_MAX_VCX - XCSI_MAX_VC) * 2)
> +
> +/* Macro to return "true" or "false" string if bit is set */
> +#define XCSI_GET_BITSET_STR(val, mask)	(val) & (mask) ? "true" : "false"
> +
> +#define XADD_MBUS(state, mbus_fmt)					\
> +	do {								\
> +		if ((state)->mbus_fmts_count < XCSI_MAX_MBUS_FMTS) {	\
> +			(state)->mbus_fmts[(state)->mbus_fmts_count++] =\
> +				(mbus_fmt);				\
> +		} else {						\
> +			dev_err((state)->core.dev,			\
> +				"accessing array out of bounds!\n");	\
> +		}							\
> +	} while (0)
> +
> +/**
> + * struct xcsi2rxss_event - Event log structure
> + * @mask: Event mask
> + * @name: Name of the event
> + */
> +struct xcsi2rxss_event {
> +	u32 mask;
> +	const char *name;
> +};
> +
> +static const struct xcsi2rxss_event xcsi2rxss_events[] = {
> +	{ XCSI_ISR_FR, "Frame Received" },
> +	{ XCSI_ISR_VCXFE, "VCX Frame Errors" },
> +	{ XCSI_ISR_WCC, "Word Count Errors" },
> +	{ XCSI_ISR_ILC, "Invalid Lane Count Error" },
> +	{ XCSI_ISR_SPFIFOF, "Short Packet FIFO OverFlow Error" },
> +	{ XCSI_ISR_SPFIFONE, "Short Packet FIFO Not Empty" },
> +	{ XCSI_ISR_SLBF, "Streamline Buffer Full Error" },
> +	{ XCSI_ISR_STOP, "Lane Stop State" },
> +	{ XCSI_ISR_SOTERR, "SOT Error" },
> +	{ XCSI_ISR_SOTSYNCERR, "SOT Sync Error" },
> +	{ XCSI_ISR_ECC2BERR, "2 Bit ECC Unrecoverable Error" },
> +	{ XCSI_ISR_ECC1BERR, "1 Bit ECC Recoverable Error" },
> +	{ XCSI_ISR_CRCERR, "CRC Error" },
> +	{ XCSI_ISR_DATAIDERR, "Data Id Error" },
> +	{ XCSI_ISR_VC3FSYNCERR, "Virtual Channel 3 Frame Sync Error" },
> +	{ XCSI_ISR_VC3FLVLERR, "Virtual Channel 3 Frame Level Error" },
> +	{ XCSI_ISR_VC2FSYNCERR, "Virtual Channel 2 Frame Sync Error" },
> +	{ XCSI_ISR_VC2FLVLERR, "Virtual Channel 2 Frame Level Error" },
> +	{ XCSI_ISR_VC1FSYNCERR, "Virtual Channel 1 Frame Sync Error" },
> +	{ XCSI_ISR_VC1FLVLERR, "Virtual Channel 1 Frame Level Error" },
> +	{ XCSI_ISR_VC0FSYNCERR, "Virtual Channel 0 Frame Sync Error" },
> +	{ XCSI_ISR_VC0FLVLERR, "Virtual Channel 0 Frame Level Error" }
> +};
> +
> +#define XCSI_NUM_EVENTS		ARRAY_SIZE(xcsi2rxss_events)
> +
> +/*
> + * struct xcsi2rxss_core - Core configuration CSI2 Rx Subsystem device structure
> + * @dev: Platform structure
> + * @iomem: Base address of subsystem
> + * @enable_active_lanes: If number of active lanes can be modified
> + * @max_num_lanes: Maximum number of lanes present
> + * @datatype: Data type filter
> + * @events: counter for events
> + * @vcx_events: counter for vcx_events
> + * @en_vcx: If more than 4 VC are enabled
> + * @clks: array of clocks
> + * @num_clks: number of clocks
> + * @rst_gpio: reset to video_aresetn
> + */
> +struct xcsi2rxss_core {
> +	struct device *dev;
> +	void __iomem *iomem;
> +	bool enable_active_lanes;
> +	u32 max_num_lanes;
> +	u32 datatype;
> +	u32 events[XCSI_NUM_EVENTS];
> +	u32 vcx_events[XCSI_VCX_NUM_EVENTS];
> +	bool en_vcx;
> +	struct clk_bulk_data *clks;
> +	int num_clks;
> +	struct gpio_desc *rst_gpio;
> +};
> +
> +/**
> + * struct xcsi2rxss_state - CSI2 Rx Subsystem device structure
> + * @core: Core structure for MIPI CSI2 Rx Subsystem
> + * @subdev: The v4l2 subdev structure
> + * @format: Active V4L2 formats on each pad
> + * @default_format: Default V4L2 format
> + * @lock: mutex for accessing this structure
> + * @pads: media pads
> + * @mbus_fmts: List of media bus formats for enum_mbus_code
> + * @mbus_fmts_count: Number of media bus formats
> + * @streaming: Flag for storing streaming state
> + *
> + * This structure contains the device driver related parameters
> + */
> +struct xcsi2rxss_state {
> +	struct xcsi2rxss_core core;
> +	struct v4l2_subdev subdev;
> +	struct v4l2_mbus_framefmt format;
> +	struct v4l2_mbus_framefmt default_format;
> +	/* used to protect access to this struct */
> +	struct mutex lock;
> +	struct media_pad pads[XCSI_MEDIA_PADS];
> +	u32 mbus_fmts[XCSI_MAX_MBUS_FMTS];
> +	u32 mbus_fmts_count;
> +	bool streaming;
> +};
> +
> +static const struct clk_bulk_data xcsi2rxss_clks[] = {
> +	{ .id = "lite_aclk" },
> +	{ .id = "video_aclk" },
> +};
> +
> +static inline struct xcsi2rxss_state *
> +to_xcsi2rxssstate(struct v4l2_subdev *subdev)
> +{
> +	return container_of(subdev, struct xcsi2rxss_state, subdev);
> +}
> +
> +/*
> + * Register related operations
> + */
> +static inline u32 xcsi2rxss_read(struct xcsi2rxss_core *xcsi2rxss, u32 addr)
> +{
> +	return ioread32(xcsi2rxss->iomem + addr);
> +}
> +
> +static inline void xcsi2rxss_write(struct xcsi2rxss_core *xcsi2rxss, u32 addr,
> +				   u32 value)
> +{
> +	iowrite32(value, xcsi2rxss->iomem + addr);
> +}
> +
> +static inline void xcsi2rxss_clr(struct xcsi2rxss_core *xcsi2rxss, u32 addr,
> +				 u32 clr)
> +{
> +	xcsi2rxss_write(xcsi2rxss, addr,
> +			xcsi2rxss_read(xcsi2rxss, addr) & ~clr);
> +}
> +
> +static inline void xcsi2rxss_set(struct xcsi2rxss_core *xcsi2rxss, u32 addr,
> +				 u32 set)
> +{
> +	xcsi2rxss_write(xcsi2rxss, addr,
> +			xcsi2rxss_read(xcsi2rxss, addr) | set);

Fits on a single line.

> +}
> +
> +static void xcsi2rxss_enable(struct xcsi2rxss_core *core)
> +{
> +	xcsi2rxss_set(core, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
> +}
> +
> +static void xcsi2rxss_disable(struct xcsi2rxss_core *core)
> +{
> +	xcsi2rxss_clr(core, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
> +}
> +
> +static void xcsi2rxss_intr_enable(struct xcsi2rxss_core *core)
> +{
> +	xcsi2rxss_clr(core, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
> +	xcsi2rxss_write(core, XCSI_IER_OFFSET, XCSI_IER_INTR_MASK);
> +	xcsi2rxss_set(core, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
> +}
> +
> +static void xcsi2rxss_intr_disable(struct xcsi2rxss_core *core)
> +{
> +	xcsi2rxss_clr(core, XCSI_IER_OFFSET, XCSI_IER_INTR_MASK);
> +	xcsi2rxss_clr(core, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
> +}
> +
> +/**
> + * xcsi2rxss_reset - Does a soft reset of the MIPI CSI2 Rx Subsystem
> + * @core: Core Xilinx CSI2 Rx Subsystem structure pointer
> + *
> + * Core takes less than 100 video clock cycles to reset.
> + * So a larger timeout value is chosen for margin.
> + *
> + * Return: 0 - on success OR -ETIME if reset times out
> + */
> +static int xcsi2rxss_reset(struct xcsi2rxss_core *core)
> +{
> +	u32 timeout = XCSI_TIMEOUT_VAL;
> +
> +	xcsi2rxss_set(core, XCSI_CCR_OFFSET, XCSI_CCR_SOFTRESET);
> +
> +	while (xcsi2rxss_read(core, XCSI_CSR_OFFSET) & XCSI_CSR_RIPCD) {
> +		if (timeout == 0) {
> +			dev_err(core->dev, "soft reset timed out!\n");
> +			return -ETIME;
> +		}
> +
> +		timeout--;
> +		udelay(1);
> +	}
> +
> +	xcsi2rxss_clr(core, XCSI_CCR_OFFSET, XCSI_CCR_SOFTRESET);
> +	return 0;
> +}
> +
> +static void xcsi2rxss_reset_event_counters(struct xcsi2rxss_state *state)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < XCSI_NUM_EVENTS; i++)
> +		state->core.events[i] = 0;
> +
> +	for (i = 0; i < XCSI_VCX_NUM_EVENTS; i++)
> +		state->core.vcx_events[i] = 0;
> +}
> +
> +/* Print event counters */
> +static void xcsi2rxss_log_counters(struct xcsi2rxss_state *state)
> +{
> +	struct xcsi2rxss_core *core = &state->core;
> +	unsigned int i;
> +
> +	for (i = 0; i < XCSI_NUM_EVENTS; i++) {
> +		if (core->events[i] > 0) {
> +			dev_info(core->dev, "%s events: %d\n",
> +				 xcsi2rxss_events[i].name,
> +				 core->events[i]);
> +		}
> +	}
> +
> +	if (core->en_vcx) {
> +		for (i = 0; i < XCSI_VCX_NUM_EVENTS; i++) {
> +			if (core->vcx_events[i] > 0) {
> +				dev_info(core->dev,
> +					 "VC %d Frame %s err vcx events: %d\n",
> +					 (i / 2) + XCSI_VCX_START,
> +					 i & 1 ? "Sync" : "Level",
> +					 core->vcx_events[i]);
> +			}
> +		}
> +	}
> +}
> +
> +static void xcsi2rxss_log_ipconfig(struct xcsi2rxss_state *state)
> +{
> +	struct xcsi2rxss_core *core = &state->core;
> +
> +	dev_dbg(core->dev, "****** Xilinx MIPI CSI2 Rx SS IP Config ******\n");
> +	dev_dbg(core->dev, "vcx is %s", core->en_vcx ? "enabled" : "disabled");
> +	dev_dbg(core->dev, "Enable active lanes property is %s\n",
> +		core->enable_active_lanes ? "present" : "absent");
> +	dev_dbg(core->dev, "Max lanes = %d", core->max_num_lanes);
> +	dev_dbg(core->dev, "Pixel format set as 0x%x\n", core->datatype);
> +	dev_dbg(core->dev, "**********************************************\n");
> +}
> +
> +/**
> + * xcsi2rxss_log_status - Logs the status of the CSI-2 Receiver
> + * @sd: Pointer to V4L2 subdevice structure
> + *
> + * This function prints the current status of Xilinx MIPI CSI-2
> + *
> + * Return: 0 on success
> + */
> +static int xcsi2rxss_log_status(struct v4l2_subdev *sd)
> +{
> +	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
> +	struct xcsi2rxss_core *core = &xcsi2rxss->core;
> +	u32 reg, data;
> +	unsigned int i, max_vc;
> +
> +	mutex_lock(&xcsi2rxss->lock);
> +
> +	xcsi2rxss_log_ipconfig(xcsi2rxss);
> +
> +	xcsi2rxss_log_counters(xcsi2rxss);
> +
> +	dev_info(core->dev, "***** Core Status *****\n");
> +	data = xcsi2rxss_read(core, XCSI_CSR_OFFSET);
> +	dev_info(core->dev, "Short Packet FIFO Full = %s\n",
> +		 XCSI_GET_BITSET_STR(data, XCSI_CSR_SPFIFOFULL));
> +	dev_info(core->dev, "Short Packet FIFO Not Empty = %s\n",
> +		 XCSI_GET_BITSET_STR(data, XCSI_CSR_SPFIFONE));
> +	dev_info(core->dev, "Stream line buffer full = %s\n",
> +		 XCSI_GET_BITSET_STR(data, XCSI_CSR_SLBF));
> +	dev_info(core->dev, "Soft reset/Core disable in progress = %s\n",
> +		 XCSI_GET_BITSET_STR(data, XCSI_CSR_RIPCD));
> +
> +	/* Clk & Lane Info  */
> +	dev_info(core->dev, "******** Clock Lane Info *********\n");
> +	data = xcsi2rxss_read(core, XCSI_CLKINFR_OFFSET);
> +	dev_info(core->dev, "Clock Lane in Stop State = %s\n",
> +		 XCSI_GET_BITSET_STR(data, XCSI_CLKINFR_STOP));
> +
> +	dev_info(core->dev, "******** Data Lane Info *********\n");
> +	dev_info(core->dev, "Lane\tSoT Error\tSoT Sync Error\tStop State\n");
> +	reg = XCSI_DLXINFR_OFFSET;
> +	for (i = 0; i < XCSI_MAXDL_COUNT; i++) {
> +		data = xcsi2rxss_read(core, reg);
> +
> +		dev_info(core->dev, "%d\t%s\t\t%s\t\t%s\n", i,
> +			 XCSI_GET_BITSET_STR(data, XCSI_DLXINFR_SOTERR),
> +			 XCSI_GET_BITSET_STR(data, XCSI_DLXINFR_SOTSYNCERR),
> +			 XCSI_GET_BITSET_STR(data, XCSI_DLXINFR_STOP));
> +
> +		reg += XCSI_NEXTREG_OFFSET;
> +	}
> +
> +	/* Virtual Channel Image Information */
> +	dev_info(core->dev, "********** Virtual Channel Info ************\n");
> +	dev_info(core->dev, "VC\tLine Count\tByte Count\tData Type\n");
> +	if (core->en_vcx)
> +		max_vc = XCSI_MAX_VCX;
> +	else
> +		max_vc = XCSI_MAX_VC;
> +
> +	reg = XCSI_VCXINF1R_OFFSET;
> +	for (i = 0; i < max_vc; i++) {
> +		u32 line_count, byte_count, data_type;
> +
> +		/* Get line and byte count from VCXINFR1 Register */
> +		data = xcsi2rxss_read(core, reg);
> +		byte_count = data & XCSI_VCXINF1R_BYTECOUNT;
> +		line_count = data & XCSI_VCXINF1R_LINECOUNT;
> +		line_count >>= XCSI_VCXINF1R_LINECOUNT_SHIFT;
> +
> +		/* Get data type from VCXINFR2 Register */
> +		reg += XCSI_NEXTREG_OFFSET;
> +		data = xcsi2rxss_read(core, reg);
> +		data_type = data & XCSI_VCXINF2R_DT;
> +
> +		dev_info(core->dev, "%d\t%d\t\t%d\t\t0x%x\n", i, line_count,
> +			 byte_count, data_type);
> +
> +		/* Move to next pair of VC Info registers */
> +		reg += XCSI_NEXTREG_OFFSET;
> +	}
> +
> +	mutex_unlock(&xcsi2rxss->lock);
> +
> +	return 0;
> +}
> +
> +static int xcsi2rxss_start_stream(struct xcsi2rxss_state *state)
> +{
> +	struct xcsi2rxss_core *core = &state->core;
> +	int ret = 0;
> +
> +	xcsi2rxss_enable(core);
> +
> +	ret = xcsi2rxss_reset(core);
> +	if (ret < 0) {
> +		state->streaming = false;
> +		return ret;
> +	}

You'll need to start streaming on the upstream sub-device somewhere in this
function.

> +
> +	xcsi2rxss_intr_enable(core);
> +	state->streaming = true;
> +
> +	return ret;
> +}
> +
> +static void xcsi2rxss_stop_stream(struct xcsi2rxss_state *state)
> +{
> +	struct xcsi2rxss_core *core = &state->core;
> +
> +	xcsi2rxss_intr_disable(core);
> +	xcsi2rxss_disable(core);
> +	state->streaming = false;

And stop it here.

> +}
> +
> +/**
> + * xcsi2rxss_irq_handler - Interrupt handler for CSI-2
> + * @irq: IRQ number
> + * @dev_id: Pointer to device state
> + *
> + * In the interrupt handler, a list of event counters are updated for
> + * corresponding interrupts. This is useful to get status / debug.
> + *
> + * Return: IRQ_HANDLED after handling interrupts
> + *         IRQ_NONE is no interrupts
> + */
> +static irqreturn_t xcsi2rxss_irq_handler(int irq, void *dev_id)
> +{
> +	struct xcsi2rxss_state *state = (struct xcsi2rxss_state *)dev_id;
> +	struct xcsi2rxss_core *core = &state->core;
> +	u32 status;
> +
> +	status = xcsi2rxss_read(core, XCSI_ISR_OFFSET) & XCSI_ISR_ALLINTR_MASK;
> +	dev_dbg_ratelimited(core->dev, "interrupt status = 0x%08x\n", status);
> +
> +	if (!status)
> +		return IRQ_NONE;
> +
> +	/* Received a short packet */
> +	if (status & XCSI_ISR_SPFIFONE) {
> +		dev_dbg_ratelimited(core->dev, "Short packet = 0x%08x\n",
> +				    xcsi2rxss_read(core, XCSI_SPKTR_OFFSET));
> +	}
> +
> +	/* Short packet FIFO overflow */
> +	if (status & XCSI_ISR_SPFIFOF)
> +		dev_dbg_ratelimited(core->dev, "Short packet FIFO overflowed\n");
> +
> +	/*
> +	 * Stream line buffer full
> +	 * This means there is a backpressure from downstream IP
> +	 */
> +	if (status & XCSI_ISR_SLBF) {
> +		dev_alert_ratelimited(core->dev, "Stream Line Buffer Full!\n");
> +		xcsi2rxss_stop_stream(state);
> +		if (core->rst_gpio) {
> +			gpiod_set_value(core->rst_gpio, 1);
> +			/* minimum 40 dphy_clk_200M cycles */
> +			ndelay(250);
> +			gpiod_set_value(core->rst_gpio, 0);
> +		}
> +	}
> +
> +	/* Increment event counters */
> +	if (status & XCSI_ISR_ALLINTR_MASK) {
> +		unsigned int i;
> +
> +		for (i = 0; i < XCSI_NUM_EVENTS; i++) {
> +			if (!(status & xcsi2rxss_events[i].mask))
> +				continue;
> +			core->events[i]++;
> +			dev_dbg_ratelimited(core->dev, "%s: %d\n",
> +					    xcsi2rxss_events[i].name,
> +					    core->events[i]);
> +		}
> +
> +		if (status & XCSI_ISR_VCXFE && core->en_vcx) {
> +			u32 vcxstatus;
> +
> +			vcxstatus = xcsi2rxss_read(core, XCSI_VCXR_OFFSET);
> +			vcxstatus &= XCSI_VCXR_VCERR;
> +			for (i = 0; i < XCSI_VCX_NUM_EVENTS; i++) {
> +				if (!(vcxstatus & (1 << i)))
> +					continue;
> +				core->vcx_events[i]++;
> +			}
> +			xcsi2rxss_write(core, XCSI_VCXR_OFFSET, vcxstatus);
> +		}
> +	}
> +
> +	xcsi2rxss_write(core, XCSI_ISR_OFFSET, status);
> +	return IRQ_HANDLED;
> +}
> +
> +/**
> + * xcsi2rxss_s_stream - It is used to start/stop the streaming.
> + * @sd: V4L2 Sub device
> + * @enable: Flag (True / False)
> + *
> + * This function controls the start or stop of streaming for the
> + * Xilinx MIPI CSI-2 Rx Subsystem.
> + *
> + * Return: 0 on success, errors otherwise
> + */
> +static int xcsi2rxss_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> +	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
> +	int ret = 0;
> +
> +	mutex_lock(&xcsi2rxss->lock);
> +
> +	if (enable) {
> +		if (!xcsi2rxss->streaming) {
> +			/* reset the event counters */
> +			xcsi2rxss_reset_event_counters(xcsi2rxss);
> +			ret = xcsi2rxss_start_stream(xcsi2rxss);
> +		}
> +	} else {
> +		if (xcsi2rxss->streaming) {
> +			struct gpio_desc *rst = xcsi2rxss->core.rst_gpio;
> +
> +			xcsi2rxss_stop_stream(xcsi2rxss);
> +			if (rst) {
> +				gpiod_set_value_cansleep(rst, 1);
> +				usleep_range(1, 2);
> +				gpiod_set_value_cansleep(rst, 0);
> +			}
> +		}
> +	}
> +
> +	mutex_unlock(&xcsi2rxss->lock);
> +	return ret;
> +}
> +
> +static struct v4l2_mbus_framefmt *
> +__xcsi2rxss_get_pad_format(struct xcsi2rxss_state *xcsi2rxss,
> +			   struct v4l2_subdev_pad_config *cfg,
> +			   unsigned int pad, u32 which)
> +{
> +	switch (which) {
> +	case V4L2_SUBDEV_FORMAT_TRY:
> +		return v4l2_subdev_get_try_format(&xcsi2rxss->subdev, cfg, pad);
> +	case V4L2_SUBDEV_FORMAT_ACTIVE:
> +		return &xcsi2rxss->format;
> +	default:
> +		return NULL;
> +	}
> +}
> +
> +/**
> + * xcsi2rxss_get_format - Get the pad format
> + * @sd: Pointer to V4L2 Sub device structure
> + * @cfg: Pointer to sub device pad information structure
> + * @fmt: Pointer to pad level media bus format
> + *
> + * This function is used to get the pad format information.
> + *
> + * Return: 0 on success
> + */
> +static int xcsi2rxss_get_format(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_pad_config *cfg,
> +				struct v4l2_subdev_format *fmt)
> +{
> +	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
> +
> +	mutex_lock(&xcsi2rxss->lock);
> +	fmt->format = *__xcsi2rxss_get_pad_format(xcsi2rxss, cfg, fmt->pad,
> +						  fmt->which);
> +	mutex_unlock(&xcsi2rxss->lock);
> +
> +	return 0;
> +}
> +
> +/**
> + * xcsi2rxss_set_format - This is used to set the pad format
> + * @sd: Pointer to V4L2 Sub device structure
> + * @cfg: Pointer to sub device pad information structure
> + * @fmt: Pointer to pad level media bus format
> + *
> + * This function is used to set the pad format. Since the pad format is fixed
> + * in hardware, it can't be modified on run time. So when a format set is
> + * requested by application, all parameters except the format type is saved
> + * for the pad and the original pad format is sent back to the application.
> + *
> + * Return: 0 on success
> + */
> +static int xcsi2rxss_set_format(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_pad_config *cfg,
> +				struct v4l2_subdev_format *fmt)
> +{
> +	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
> +	struct xcsi2rxss_core *core = &xcsi2rxss->core;
> +	struct v4l2_mbus_framefmt *__format;
> +
> +	/* only sink pad format can be updated */
> +	mutex_lock(&xcsi2rxss->lock);
> +
> +	/*
> +	 * Only the format->code parameter matters for CSI as the
> +	 * CSI format cannot be changed at runtime.
> +	 * Ensure that format to set is copied to over to CSI pad format
> +	 */
> +	__format = __xcsi2rxss_get_pad_format(xcsi2rxss, cfg,
> +					      fmt->pad, fmt->which);
> +
> +	if (fmt->pad == XVIP_PAD_SOURCE) {
> +		fmt->format = *__format;
> +		mutex_unlock(&xcsi2rxss->lock);
> +		return 0;
> +	}
> +
> +	/*
> +	 * RAW8 is supported in all datatypes. So if requested media bus format
> +	 * is of RAW8 type, then allow to be set. In case core is configured to
> +	 * other RAW, YUV422 8/10 or RGB888, set appropriate media bus format.
> +	 */
> +	if (!((fmt->format.code == MEDIA_BUS_FMT_SBGGR8_1X8 ||
> +	       fmt->format.code == MEDIA_BUS_FMT_SGBRG8_1X8 ||
> +	       fmt->format.code == MEDIA_BUS_FMT_SGRBG8_1X8 ||
> +	       fmt->format.code == MEDIA_BUS_FMT_SRGGB8_1X8) ||
> +	      (core->datatype == XCSI_DT_RAW10 &&
> +	       (fmt->format.code == MEDIA_BUS_FMT_SBGGR10_1X10 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SGBRG10_1X10 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SGRBG10_1X10 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SRGGB10_1X10)) ||
> +	      (core->datatype == XCSI_DT_RAW12 &&
> +	       (fmt->format.code == MEDIA_BUS_FMT_SBGGR12_1X12 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SGBRG12_1X12 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SGRBG12_1X12 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SRGGB12_1X12)) ||
> +	      (core->datatype == XCSI_DT_RAW14 &&
> +	       (fmt->format.code == MEDIA_BUS_FMT_SBGGR14_1X14 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SGBRG14_1X14 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SGRBG14_1X14 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SRGGB14_1X14)) ||
> +	      (core->datatype == XCSI_DT_RAW16 &&
> +	       (fmt->format.code == MEDIA_BUS_FMT_SBGGR16_1X16 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SGBRG16_1X16 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SGRBG16_1X16 ||
> +		fmt->format.code == MEDIA_BUS_FMT_SRGGB16_1X16)) ||
> +	      (core->datatype == XCSI_DT_YUV4228B &&
> +	       fmt->format.code == MEDIA_BUS_FMT_UYVY8_1X16) ||
> +	      (core->datatype == XCSI_DT_YUV42210B &&
> +	       fmt->format.code == MEDIA_BUS_FMT_UYVY10_1X20) ||
> +	      (core->datatype == XCSI_DT_RGB888 &&
> +	       fmt->format.code == MEDIA_BUS_FMT_RBG888_1X24))) {
> +		/* Restore the original pad format code */
> +		dev_dbg(core->dev, "Unsupported media bus format");
> +		fmt->format.code = __format->code;
> +	}
> +
> +	*__format = fmt->format;

Did I already ask whether there are any limits on width or height for this
device?

> +	mutex_unlock(&xcsi2rxss->lock);
> +
> +	return 0;
> +}
> +
> +/*
> + * xcsi2rxss_enum_mbus_code - Handle pixel format enumeration
> + * @sd : pointer to v4l2 subdev structure
> + * @cfg: V4L2 subdev pad configuration
> + * @code : pointer to v4l2_subdev_mbus_code_enum structure
> + *
> + * Return: -EINVAL or zero on success
> + */
> +int xcsi2rxss_enum_mbus_code(struct v4l2_subdev *sd,
> +			     struct v4l2_subdev_pad_config *cfg,
> +			     struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	struct xcsi2rxss_state *state = to_xcsi2rxssstate(sd);
> +
> +	if (code->index >= state->mbus_fmts_count)
> +		return -EINVAL;
> +
> +	code->code = state->mbus_fmts[code->index];
> +
> +	return 0;
> +}
> +
> +/**
> + * xcsi2rxss_open - Called on v4l2_open()
> + * @sd: Pointer to V4L2 sub device structure
> + * @fh: Pointer to V4L2 File handle
> + *
> + * This function is called on v4l2_open(). It sets the default format
> + * for both pads.
> + *
> + * Return: 0 on success
> + */
> +static int xcsi2rxss_open(struct v4l2_subdev *sd,
> +			  struct v4l2_subdev_fh *fh)
> +{
> +	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
> +	struct v4l2_mbus_framefmt *format;
> +	unsigned int i;
> +
> +	for (i = 0; i < XCSI_MEDIA_PADS; i++) {
> +		format = v4l2_subdev_get_try_format(sd, fh->pad, i);
> +		*format = xcsi2rxss->default_format;
> +	}
> +
> +	return 0;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Media Operations
> + */
> +
> +static const struct media_entity_operations xcsi2rxss_media_ops = {
> +	.link_validate = v4l2_subdev_link_validate
> +};
> +
> +static const struct v4l2_subdev_core_ops xcsi2rxss_core_ops = {
> +	.log_status = xcsi2rxss_log_status,
> +};
> +
> +static const struct v4l2_subdev_video_ops xcsi2rxss_video_ops = {
> +	.s_stream = xcsi2rxss_s_stream
> +};
> +
> +static const struct v4l2_subdev_pad_ops xcsi2rxss_pad_ops = {
> +	.get_fmt = xcsi2rxss_get_format,
> +	.set_fmt = xcsi2rxss_set_format,
> +	.enum_mbus_code = xcsi2rxss_enum_mbus_code,

You'll need link_validate set to v4l2_subdev_link_validate_default here.

> +};
> +
> +static const struct v4l2_subdev_ops xcsi2rxss_ops = {
> +	.core = &xcsi2rxss_core_ops,
> +	.video = &xcsi2rxss_video_ops,
> +	.pad = &xcsi2rxss_pad_ops
> +};
> +
> +static const struct v4l2_subdev_internal_ops xcsi2rxss_internal_ops = {
> +	.open = xcsi2rxss_open,
> +};
> +
> +static void xcsi2rxss_set_default_format(struct xcsi2rxss_state *state)
> +{
> +	struct xcsi2rxss_core *core = &state->core;
> +
> +	memset(&state->default_format, 0, sizeof(state->default_format));
> +
> +	switch (core->datatype) {
> +	case XCSI_DT_YUV4228B:
> +		state->default_format.code = MEDIA_BUS_FMT_UYVY8_1X16;
> +		break;
> +	case XCSI_DT_RGB888:
> +		state->default_format.code = MEDIA_BUS_FMT_RBG888_1X24;
> +		break;
> +	case XCSI_DT_YUV42210B:
> +		state->default_format.code = MEDIA_BUS_FMT_UYVY10_1X20;
> +		break;
> +	case XCSI_DT_RAW10:
> +		state->default_format.code = MEDIA_BUS_FMT_SRGGB10_1X10;
> +		break;
> +	case XCSI_DT_RAW12:
> +		state->default_format.code = MEDIA_BUS_FMT_SRGGB12_1X12;
> +		break;
> +	case XCSI_DT_RAW14:
> +		state->default_format.code = MEDIA_BUS_FMT_SRGGB14_1X14;
> +		break;
> +	case XCSI_DT_RAW16:
> +		state->default_format.code = MEDIA_BUS_FMT_SRGGB16_1X16;
> +		break;
> +	case XCSI_DT_RAW8:
> +	case XCSI_DT_RGB444:
> +	case XCSI_DT_RGB555:
> +	case XCSI_DT_RGB565:
> +	case XCSI_DT_RGB666:
> +		state->default_format.code = MEDIA_BUS_FMT_SRGGB8_1X8;
> +		break;
> +	}
> +
> +	state->default_format.field = V4L2_FIELD_NONE;
> +	state->default_format.colorspace = V4L2_COLORSPACE_SRGB;
> +	state->default_format.width = XCSI_DEFAULT_WIDTH;
> +	state->default_format.height = XCSI_DEFAULT_HEIGHT;
> +
> +	dev_dbg(core->dev, "default mediabus format = 0x%x",
> +		state->default_format.code);
> +}
> +
> +static void xcsi2rxss_init_mbus_fmts(struct xcsi2rxss_state *state)
> +{
> +	struct xcsi2rxss_core *core = &state->core;
> +
> +	XADD_MBUS(state, MEDIA_BUS_FMT_SRGGB8_1X8);
> +	XADD_MBUS(state, MEDIA_BUS_FMT_SBGGR8_1X8);
> +	XADD_MBUS(state, MEDIA_BUS_FMT_SGRBG8_1X8);
> +	XADD_MBUS(state, MEDIA_BUS_FMT_SGBRG8_1X8);
> +
> +	switch (core->datatype) {
> +	case XCSI_DT_RAW10:
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SRGGB10_1X10);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SBGGR10_1X10);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SGRBG10_1X10);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SGBRG10_1X10);
> +		break;
> +	case XCSI_DT_RAW12:
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SRGGB12_1X12);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SBGGR12_1X12);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SGRBG12_1X12);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SGBRG12_1X12);
> +		break;
> +	case XCSI_DT_RAW14:
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SRGGB14_1X14);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SBGGR14_1X14);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SGRBG14_1X14);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SGBRG14_1X14);
> +		break;
> +	case XCSI_DT_RAW16:
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SRGGB16_1X16);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SBGGR16_1X16);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SGRBG16_1X16);
> +		XADD_MBUS(state, MEDIA_BUS_FMT_SGBRG16_1X16);
> +		break;
> +	case XCSI_DT_YUV4228B:
> +		XADD_MBUS(state, MEDIA_BUS_FMT_UYVY8_1X16);
> +		break;
> +	case XCSI_DT_RGB888:
> +		XADD_MBUS(state, MEDIA_BUS_FMT_RBG888_1X24);
> +		break;
> +	case XCSI_DT_YUV42210B:
> +		XADD_MBUS(state, MEDIA_BUS_FMT_UYVY10_1X20);
> +		break;
> +	default:
> +		dev_err(core->dev, "Invalid data type!\n");
> +	}
> +}
> +
> +static int xcsi2rxss_parse_of(struct xcsi2rxss_state *xcsi2rxss)
> +{
> +	struct xcsi2rxss_core *core = &xcsi2rxss->core;
> +	struct device_node *node = xcsi2rxss->core.dev->of_node;
> +	struct device_node *ports = NULL;
> +	struct device_node *port = NULL;
> +	unsigned int nports, irq;
> +	bool en_csi_v20, vfb;
> +	int ret;
> +
> +	en_csi_v20 = of_property_read_bool(node, "xlnx,en-csi-v2-0");
> +	if (en_csi_v20)
> +		core->en_vcx = of_property_read_bool(node, "xlnx,en-vcx");
> +
> +	core->enable_active_lanes =
> +		of_property_read_bool(node, "xlnx,en-active-lanes");
> +
> +	ret = of_property_read_u32(node, "xlnx,csi-pxl-format",
> +				   &core->datatype);
> +	if (ret < 0) {
> +		dev_err(core->dev, "missing xlnx,csi-pxl-format property\n");
> +		return ret;
> +	}
> +
> +	switch (core->datatype) {
> +	case XCSI_DT_YUV4228B:
> +	case XCSI_DT_RGB444:
> +	case XCSI_DT_RGB555:
> +	case XCSI_DT_RGB565:
> +	case XCSI_DT_RGB666:
> +	case XCSI_DT_RGB888:
> +	case XCSI_DT_RAW6:
> +	case XCSI_DT_RAW7:
> +	case XCSI_DT_RAW8:
> +	case XCSI_DT_RAW10:
> +	case XCSI_DT_RAW12:
> +	case XCSI_DT_RAW14:
> +		break;
> +	case XCSI_DT_YUV42210B:
> +	case XCSI_DT_RAW16:
> +	case XCSI_DT_RAW20:
> +		if (!en_csi_v20) {
> +			ret = -EINVAL;
> +			dev_dbg(core->dev, "enable csi v2 for this pixel format");
> +		}
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
> +	if (ret < 0) {
> +		dev_err(core->dev, "invalid csi-pxl-format property!\n");
> +		return ret;
> +	}
> +
> +	vfb = of_property_read_bool(node, "xlnx,vfb");
> +	if (!vfb) {
> +		dev_err(core->dev, "failed as VFB is disabled!\n");
> +		return -EINVAL;
> +	}
> +
> +	ports = of_get_child_by_name(node, "ports");
> +	if (!ports)
> +		ports = node;
> +
> +	nports = 0;
> +	for_each_child_of_node(ports, port) {
> +		struct device_node *endpoint;
> +		struct v4l2_fwnode_endpoint v4lendpoint;
> +		int ret;
> +
> +		if (!port->name || of_node_cmp(port->name, "port"))
> +			continue;
> +
> +		endpoint = of_get_next_child(port, NULL);
> +		if (!endpoint) {
> +			dev_err(core->dev, "No port at\n");
> +			return -EINVAL;
> +		}

You shouldn't parse the graph data structure yourself.

Could you use fwnode_graph_get_endpoint_by_id(), and work it from there
without using an enumeration? You have two endpoints in there after all in
two ports.

Please see drivers/media/pci/intel/ipu3/ipu3-cio2.c for an example.

> +
> +		/*
> +		 * since first port is sink port and it contains
> +		 * all info about data-lanes and cfa-pattern,
> +		 * don't parse second port but only check if exists
> +		 */
> +		if (nports == XVIP_PAD_SOURCE) {
> +			dev_dbg(core->dev, "no need to parse source port");
> +			nports++;
> +			of_node_put(endpoint);
> +			continue;
> +		}
> +
> +		ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(endpoint),
> +						 &v4lendpoint);

Please set the bus_type to what you need on that port, e.g.
V4L2_MBUS_CSI2_DPHY, and set the rest to zero.

> +		of_node_put(endpoint);
> +		if (ret)
> +			return ret;
> +
> +		dev_dbg(core->dev, "%s : port %d bus type = %d\n",
> +			__func__, nports, v4lendpoint.bus_type);
> +
> +		if (v4lendpoint.bus_type == V4L2_MBUS_CSI2_DPHY) {
> +			dev_dbg(core->dev, "%s : base.port = %d base.id = %d\n",
> +				__func__, v4lendpoint.base.port,
> +				v4lendpoint.base.id);
> +
> +			dev_dbg(core->dev, "%s : mipi number lanes = %d\n",
> +				__func__,
> +				v4lendpoint.bus.mipi_csi2.num_data_lanes);
> +
> +			core->max_num_lanes =
> +				v4lendpoint.bus.mipi_csi2.num_data_lanes;
> +		}
> +
> +		/* Count the number of ports. */
> +		nports++;
> +	}
> +
> +	if (nports != XCSI_MEDIA_PADS) {
> +		dev_err(core->dev, "invalid number of ports %u\n", nports);
> +		return -EINVAL;
> +	}
> +
> +	/* Register interrupt handler */
> +	irq = irq_of_parse_and_map(node, 0);
> +	ret = devm_request_irq(core->dev, irq, xcsi2rxss_irq_handler,
> +			       IRQF_SHARED, "xilinx-csi2rxss", xcsi2rxss);
> +	if (ret) {
> +		dev_err(core->dev, "Err = %d Interrupt handler reg failed!\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	xcsi2rxss_log_ipconfig(xcsi2rxss);
> +
> +	return 0;
> +}
> +
> +static int xcsi2rxss_probe(struct platform_device *pdev)
> +{
> +	struct v4l2_subdev *subdev;
> +	struct xcsi2rxss_state *xcsi2rxss;
> +	struct xcsi2rxss_core *core;
> +	struct resource *res;
> +	int ret;
> +
> +	xcsi2rxss = devm_kzalloc(&pdev->dev, sizeof(*xcsi2rxss), GFP_KERNEL);
> +	if (!xcsi2rxss)
> +		return -ENOMEM;
> +
> +	core = &xcsi2rxss->core;
> +	core->dev = &pdev->dev;
> +
> +	core->clks = devm_kmemdup(core->dev, xcsi2rxss_clks,
> +				  sizeof(xcsi2rxss_clks), GFP_KERNEL);
> +	if (!core->clks)
> +		return -ENOMEM;
> +
> +	/* Reset GPIO */
> +	core->rst_gpio = devm_gpiod_get_optional(core->dev, "reset",
> +						 GPIOD_OUT_HIGH);
> +	if (IS_ERR(core->rst_gpio)) {
> +		if (PTR_ERR(core->rst_gpio) != -EPROBE_DEFER)
> +			dev_err(core->dev, "Video Reset GPIO not setup in DT");
> +		return PTR_ERR(core->rst_gpio);
> +	}
> +
> +	mutex_init(&xcsi2rxss->lock);
> +
> +	ret = xcsi2rxss_parse_of(xcsi2rxss);
> +	if (ret < 0)
> +		return ret;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	core->iomem = devm_ioremap_resource(core->dev, res);
> +	if (IS_ERR(core->iomem))
> +		return PTR_ERR(core->iomem);
> +
> +	core->num_clks = ARRAY_SIZE(xcsi2rxss_clks);

num_clks never changes, please drop it and  use ARRAY_SIZE(...) instead.

> +
> +	ret = clk_bulk_get(core->dev, core->num_clks, core->clks);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_bulk_prepare_enable(core->num_clks, core->clks);
> +	if (ret)
> +		goto err_clk_put;
> +
> +	if (core->rst_gpio) {
> +		gpiod_set_value_cansleep(core->rst_gpio, 1);
> +		/* minimum of 40 dphy_clk_200M cycles */
> +		usleep_range(1, 2);
> +		gpiod_set_value_cansleep(core->rst_gpio, 0);
> +	}
> +
> +	xcsi2rxss_reset(core);
> +
> +	/* Initialize V4L2 subdevice and media entity */
> +	xcsi2rxss->pads[XVIP_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> +	xcsi2rxss->pads[XVIP_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> +
> +	/* Initialize the default format */
> +	xcsi2rxss_set_default_format(xcsi2rxss);
> +
> +	/* Initialize the mbus formats supported */
> +	xcsi2rxss_init_mbus_fmts(xcsi2rxss);
> +
> +	/* Initialize V4L2 subdevice and media entity */
> +	subdev = &xcsi2rxss->subdev;
> +	v4l2_subdev_init(subdev, &xcsi2rxss_ops);
> +	subdev->dev = &pdev->dev;
> +	subdev->internal_ops = &xcsi2rxss_internal_ops;
> +	strscpy(subdev->name, dev_name(&pdev->dev), sizeof(subdev->name));
> +	subdev->flags |= V4L2_SUBDEV_FL_HAS_EVENTS | V4L2_SUBDEV_FL_HAS_DEVNODE;
> +	subdev->entity.ops = &xcsi2rxss_media_ops;
> +	v4l2_set_subdevdata(subdev, xcsi2rxss);
> +
> +	ret = media_entity_pads_init(&subdev->entity, XCSI_MEDIA_PADS,
> +				     xcsi2rxss->pads);
> +	if (ret < 0)
> +		goto error;
> +
> +	platform_set_drvdata(pdev, xcsi2rxss);
> +
> +	ret = v4l2_async_register_subdev(subdev);
> +	if (ret < 0) {
> +		dev_err(core->dev, "failed to register subdev\n");
> +		goto error;
> +	}
> +
> +	dev_info(core->dev, "Xilinx CSI2 Rx Subsystem device found!\n");
> +
> +	return 0;
> +error:
> +	media_entity_cleanup(&subdev->entity);
> +	mutex_destroy(&xcsi2rxss->lock);
> +	clk_bulk_disable_unprepare(core->num_clks, core->clks);
> +err_clk_put:
> +	clk_bulk_put(core->num_clks, core->clks);
> +	return ret;
> +}
> +
> +static int xcsi2rxss_remove(struct platform_device *pdev)
> +{
> +	struct xcsi2rxss_state *xcsi2rxss = platform_get_drvdata(pdev);
> +	struct xcsi2rxss_core *core = &xcsi2rxss->core;
> +	struct v4l2_subdev *subdev = &xcsi2rxss->subdev;
> +
> +	v4l2_async_unregister_subdev(subdev);
> +	media_entity_cleanup(&subdev->entity);
> +	mutex_destroy(&xcsi2rxss->lock);
> +	clk_bulk_disable_unprepare(core->num_clks, core->clks);
> +	clk_bulk_put(core->num_clks, core->clks);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id xcsi2rxss_of_id_table[] = {
> +	{ .compatible = "xlnx,mipi-csi2-rx-subsystem-4.0", },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, xcsi2rxss_of_id_table);
> +
> +static struct platform_driver xcsi2rxss_driver = {
> +	.driver = {
> +		.name		= "xilinx-csi2rxss",
> +		.of_match_table	= xcsi2rxss_of_id_table,
> +	},
> +	.probe			= xcsi2rxss_probe,
> +	.remove			= xcsi2rxss_remove,
> +};
> +
> +module_platform_driver(xcsi2rxss_driver);
> +
> +MODULE_AUTHOR("Vishal Sagar <vsagar@xilinx.com>");
> +MODULE_DESCRIPTION("Xilinx MIPI CSI2 Rx Subsystem Driver");
> +MODULE_LICENSE("GPL v2");

This does not align with the SPDX header. v2 or v2+?

-- 
Regards,

Sakari Ailus