Re: [PATCH v11 2/2] media: v4l: xilinx: Add Xilinx MIPI CSI-2 Rx Subsystem driver
From: Laurent Pinchart
Date: Sun Apr 19 2020 - 14:02:41 EST
Hi Vishal,
Thank you for the patch.
On Fri, Apr 10, 2020 at 01:14:24AM +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@xxxxxxxxxx>
> Reviewed-by: Hyun Kwon <hyun.kwon@xxxxxxxxxx>
> ---
> v11
> - Fixed changes as suggested by Sakari Ailus
> - Removed VIDEO_XILINX from KConfig
> - Minor formatting
> - Start / Stop upstream sub-device in xcsi2rxss_start_stream()
> and xcsi2rxss_stop_stream()
> - Added v4l2_subdev_link_validate_default() in v4l2_subdev_pad_ops()
> - Use fwnode_graph_get_endpoint_by_id() instead of parsing by self
> - Set bus type as V4L2_MBUS_CSI2_DPHY in struct v4l2_fwnode_endpoint
> - Remove num_clks from core. Instead use ARRAY_SIZE()
> - Fixed SPDX header to GPL-2.0
> - Update copyright year to 2020
>
> 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 | 10 +
> drivers/media/platform/xilinx/Makefile | 1 +
> .../media/platform/xilinx/xilinx-csi2rxss.c | 1234 +++++++++++++++++
> 3 files changed, 1245 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..cd1a0fdde4df 100644
> --- a/drivers/media/platform/xilinx/Kconfig
> +++ b/drivers/media/platform/xilinx/Kconfig
> @@ -10,6 +10,16 @@ config VIDEO_XILINX
>
> if VIDEO_XILINX
>
> +config VIDEO_XILINX_CSI2RXSS
> + tristate "Xilinx CSI2 Rx Subsystem"
> + help
> + Driver for Xilinx MIPI CSI2 Rx Subsystem. This is a V4L sub-device
As for the bindings, s/CSI2/CSI-2/ and s/DPHY/D-PHY/ through this patch.
> + 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
The I2C controller has been removed in v4.1, it should be dropped from
here.
> + 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..083422768ebd
> --- /dev/null
> +++ b/drivers/media/platform/xilinx/xilinx-csi2rxss.c
> @@ -0,0 +1,1234 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for Xilinx MIPI CSI2 Rx Subsystem
> + *
> + * Copyright (C) 2016 - 2020 Xilinx, Inc.
> + *
> + * Contacts: Vishal Sagar <vishal.sagar@xxxxxxxxxx>
> + *
> + */
> +#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)
These macros are only used in XCSI_ISR_ALLINTR_MASK, do we need them ?
> +
> +#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
Those two macros are not used, maybe we could drop them ?
> +#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
Isn't 8 enough ?
> +
> +/* Max string length for CSI Data type string */
> +#define XCSI_PXLFMT_STRLEN_MAX 16
This isn't used either.
> +
> +/* 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
Could you please use lower-case for hex constants ?
> +
> +#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"
I would inline this in xcsi2rxss_log_status() where the macro is used.
> +
> +#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
> + * @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;
> + 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;
> +};
Is there a need to have two separate data structures, can't they be
merged ?
> +
> +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);
> +}
> +
> +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);
> +}
I'd find the code more readable if we inlined those four functions in
their single call site, with a one-line comment explaining what happens
(e.g. /* Enable interrupts */), but that may be a matter of personal
taste.
> +
> +/**
> + * 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);
I understand the reset time is guaranteed to be lower than 100 video
clock cycles, but what is the typical time ? It's a bit pointless to
busy loop with a very short delay if a larger delay is typically needed.
> + }
> +
> + 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");
How about making this more compact ?
dev_dbg(core->dev, "vcx %s, %u data lanes (%s), data type 0x%02x\n",
core->en_vcx ? "enabled" : "disabled",
core->max_num_lanes,
core->enable_active_lanes ? "dynamic" : "static",
core->datatype);
> +}
> +
> +/**
> + * 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);
Do we need to print this here, as it's printed at probe time already and
only contains static data ? I would inline xcsi2rxss_log_ipconfig() in
xcsi2rxss_parse_of().
> +
> + 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 struct v4l2_subdev *xcsi2rxss_get_remote_subdev(struct media_pad *local)
> +{
> + struct media_pad *remote;
> +
> + remote = media_entity_remote_pad(local);
> + if (!remote || !is_media_entity_v4l2_subdev(remote->entity))
> + return NULL;
> +
> + return media_entity_to_v4l2_subdev(remote->entity);
> +}
> +
> +static int xcsi2rxss_start_stream(struct xcsi2rxss_state *state)
> +{
> + struct xcsi2rxss_core *core = &state->core;
> + struct v4l2_subdev *rsubdev;
> + int ret = 0;
> +
> + xcsi2rxss_enable(core);
> +
> + ret = xcsi2rxss_reset(core);
> + if (ret < 0) {
> + state->streaming = false;
> + return ret;
> + }
> +
> + xcsi2rxss_intr_enable(core);
> + state->streaming = true;
> +
> + rsubdev = xcsi2rxss_get_remote_subdev(&state->pads[XVIP_PAD_SINK]);
How about storing the remote subdev pointer in the xcsi2rxss_state
structure, either at probe time, or at streamon time ?
> + ret = v4l2_subdev_call(rsubdev, video, s_stream, 1);
If this failes, you should disabled interrupts, disable the receiver,
and set state->streaming to false. I would actually set state->streaming
= enable at the end of xcsi2rxss_s_stream() instead of here and in
xcsi2rxss_stop_stream().
> +
> + return ret;
> +}
> +
> +static void xcsi2rxss_stop_stream(struct xcsi2rxss_state *state)
> +{
> + struct xcsi2rxss_core *core = &state->core;
> + struct v4l2_subdev *rsubdev;
> +
> + rsubdev = xcsi2rxss_get_remote_subdev(&state->pads[XVIP_PAD_SINK]);
> + v4l2_subdev_call(rsubdev, video, s_stream, 0);
> +
> + xcsi2rxss_intr_disable(core);
> + xcsi2rxss_disable(core);
> + state->streaming = false;
> +}
> +
> +/**
> + * 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);
As this is expected to occur for every frame, I would drop the message,
even if rate-limited.
> +
> + 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));
> + }
Same here, this will occur all the time, I'd remove this message. You
need to read XCSI_SPKTR_OFFSET though, and you should do so in a loop
until the XCSI_CSR_SPFIFONE in XCSI_CSR_OFFSET is cleared in case
multiple short packets are received before the interrupt handler
executes.
I also wonder if it would make sense to extract the frame number from
the FS short packet, and make it available through the subdev API. I
think it should be reported through a V4L2_EVENT_FRAME_SYNC event. This
can be implemented later.
> +
> + /* 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);
> + }
I don't think you should stop the core here. xcsi2rxss_stop_stream()
calls the source .s_stream(0) operation, which usually involves I2C
writes that will sleep.
You should instead report an event to userspace (it looks like we have
no error event defined in V4L2, one should be added), and rely on the
normal stop procedure.
> + }
> +
> + /* 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",
The counter is unsigned, this should be %u instead of %d.
> + 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);
To lower the probability of losing events, shouldn't you write the
register right after reading it above ? Same for XCSI_VCXR_OFFSET.
> + 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);
> +
You could add
if (enable == xcsi2rxss->streaming)
goto done;
with a done label just before mutex_unlock(), and simplify the code
below by removing the xcsi2rxss->streaming checks.
> + 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))) {
I think you should create a static const table of format information,
mapping media bus codes to CSI-2 data types. It can be useful here, in
xcsi2rxss_set_default_format() and in xcsi2rxss_init_mbus_fmts().
> + /* Restore the original pad format code */
> + dev_dbg(core->dev, "Unsupported media bus format");
> + fmt->format.code = __format->code;
You should use the default here instead of the current format.
> + }
> +
> + *__format = fmt->format;
> + 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];
Instead of storing mbus_fmts and mbus_fmts_count in the state, how about
moving the logic from xcsi2rxss_init_mbus_fmts() to here ?
> +
> + 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;
> + }
I would recommend moving this logic to the .init_cfg() pad operation,
and removing the .open() internal operation.
> +
> + 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,
> + .link_validate = v4l2_subdev_link_validate_default,
> +};
> +
> +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));
state is kzalloc'ed, so you can skip this.
> +
> + 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;
This is correct for XCSI_DT_RAW8 but not for the other RGB data types.
> + 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);
I'd drop this as there's already a debug message that prints the data
type.
> +}
> +
> +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;
> + 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");
I'd write this "operation without VFB is not supported\n". Do you plan
to add support for this later ?
> + return -EINVAL;
> + }
> +
> + for (nports = 0; nports < XCSI_MEDIA_PADS; nports++) {
> + struct fwnode_handle *ep;
> + struct v4l2_fwnode_endpoint vep = {
> + .bus_type = V4L2_MBUS_CSI2_DPHY
> + };
> +
> + ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(core->dev),
> + nports, 0,
> + FWNODE_GRAPH_ENDPOINT_NEXT);
> + if (!ep)
> + break;
> + /*
> + * 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");
> + fwnode_handle_put(ep);
> + continue;
> + }
How about removing the loop and only handling port 0 then ?
> +
> + ret = v4l2_fwnode_endpoint_parse(ep, &vep);
You can add
fwnode_handle_put(ep);
here,
> + if (ret) {
> + dev_err(core->dev, "error parsing sink port");
> + fwnode_handle_put(ep);
and drop it from there and from the end of the loop.
> + return ret;
> + }
> +
> + dev_dbg(core->dev, "port %d bus type = %d\n", nports,
> + vep.bus_type);
As bus_type is hardcoded to V4L2_MBUS_CSI2_DPHY and nports can always be
0 here, I think you can drop this message.
> +
> + if (vep.bus_type == V4L2_MBUS_CSI2_DPHY) {
Can bus_type be different than V4L2_MBUS_CSI2_DPHY here, as you set it
when initializing vep above ? I think you can remove the condition
check, as well as the first debug message below.
> + dev_dbg(core->dev, "base.port = %d base.id = %d\n",
> + vep.base.port, vep.base.id);
> +
> + dev_dbg(core->dev, "mipi number lanes = %d\n",
> + vep.bus.mipi_csi2.num_data_lanes);
> +
> + core->max_num_lanes =
> + vep.bus.mipi_csi2.num_data_lanes;
> + }
> + fwnode_handle_put(ep);
> + }
> +
> + if (nports != XCSI_MEDIA_PADS) {
> + dev_err(core->dev, "invalid number of ports %u\n", nports);
> + return -EINVAL;
> + }
I think we can drop this check too.
> +
> + /* Register interrupt handler */
> + irq = irq_of_parse_and_map(node, 0);
This should be turned into platform_get_irq().
> + 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;
> + }
And IRQ handling should be moved to xcsi2rxss_probe() as it's not
related to OF parsing.
> +
> + 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 num_clks = ARRAY_SIZE(xcsi2rxss_clks);
> + 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);
You can replace those two lines with
core->iomem = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(core->iomem))
> + return PTR_ERR(core->iomem);
> +
> + ret = clk_bulk_get(core->dev, num_clks, core->clks);
> + if (ret)
> + return ret;
> +
> + ret = clk_bulk_prepare_enable(num_clks, core->clks);
> + if (ret)
> + goto err_clk_put;
Shouldn't be clock enabled when starting the stream, and disabled when
stopping it ?
> +
> + 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);
> + }
This is done in xcsi2rxss_s_stream() too, I would move the logic to a
xcsi2rxss_hard_reset() function.
> +
> + xcsi2rxss_reset(core);
And rename this xcsi2rxss_soft_reset();
> +
> + /* 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);
> + xcsi2rxss->format = xcsi2rxss->default_format;
> +
> + /* 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");
I'd drop the "!".
> +
> + return 0;
> +error:
> + media_entity_cleanup(&subdev->entity);
> + mutex_destroy(&xcsi2rxss->lock);
This should go below, just before return ret, and you should add another
error label there as mutex_destroy() should be called for a few error
cases that currently return directly.
> + clk_bulk_disable_unprepare(num_clks, core->clks);
> +err_clk_put:
> + clk_bulk_put(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;
> + int num_clks = ARRAY_SIZE(xcsi2rxss_clks);
> +
> + v4l2_async_unregister_subdev(subdev);
> + media_entity_cleanup(&subdev->entity);
> + mutex_destroy(&xcsi2rxss->lock);
> + clk_bulk_disable_unprepare(num_clks, core->clks);
> + clk_bulk_put(num_clks, core->clks);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id xcsi2rxss_of_id_table[] = {
> + { .compatible = "xlnx,mipi-csi2-rx-subsystem-5.0", },
> + { }
> +};
> +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@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("Xilinx MIPI CSI2 Rx Subsystem Driver");
> +MODULE_LICENSE("GPL v2");
--
Regards,
Laurent Pinchart