RE: [PATCH v12 2/2] media: v4l: xilinx: Add Xilinx MIPI CSI-2 Rx Subsystem driver
From: Vishal Sagar
Date: Mon May 11 2020 - 10:05:21 EST
Hi Laurent,
Thanks for reviewing this patch.
> -----Original Message-----
> From: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Sent: Wednesday, May 6, 2020 4:23 AM
> To: Vishal Sagar <vsagar@xxxxxxxxxx>
> Cc: Hyun Kwon <hyunk@xxxxxxxxxx>; mchehab@xxxxxxxxxx;
> robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; hans.verkuil@xxxxxxxxx; Luca
> Ceresoli <luca@xxxxxxxxxxxxxxxx>; Jacopo Mondi <jacopo@xxxxxxxxxx>;
> Michal Simek <michals@xxxxxxxxxx>; linux-media@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; Dinesh Kumar <dineshk@xxxxxxxxxx>; Sandip Kothari
> <sandipk@xxxxxxxxxx>; Hyun Kwon <hyunk@xxxxxxxxxx>
> Subject: Re: [PATCH v12 2/2] media: v4l: xilinx: Add Xilinx MIPI CSI-2 Rx
> Subsystem driver
>
> Hi Vishal,
>
> Thank you for the patch.
>
> On Thu, Apr 23, 2020 at 09:00:38PM +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>
> > ---
> > v12
> > - Changes done as suggested by Laurent Pinchart and Luca Ceresoli
> > - Removed unused macros
> > - No local storage of supported formats
> > - Dropped init mbus fmts and removed xcsi2rxss_init_mbus_fmts()
> > - XCSI_GET_BITSET_STR removed
> > - Add data type and mbus LUT
> > - Added xcsi2rxss_get_nth_mbus() and xcsi2rxss_get_dt()
> > - Replaced all core->dev with dev in dev_dbg() and related debug
> > prints
> > - Replaced xcsi2rxss_log_ipconfig() with single line
> > - Removed small functions to enable/disable interrupts and core
> > - Now save remote subdev in state struct before streaming on
> > - Made xcsi2rxss_reset as soft_reset()
> > - Added hard reset using video-reset gpio
> > - 2 modes one with delay and another sleep
> > - Instead of reset-gpios it is not video-reset-gpios
> > - In irq handler
> > - Moved clearing of ISR up
> > - Dump / empty short packet fifo
> > - Irq handler is now threaded
> > - Added init_cfg pad ops and removed open()
> > - Updated xcsi2rxss_set_format(), xcsi2rxss_enum_mbus_code() to use
> > the dt mbus lut
> > - xcsi2rxss_set_default_format() updated
> > - Moved mutex_init()
> > - Updated graph handling
> > - Removed unnecessary prints
> > - Use devm_platform_ioremap_resource() and platform_get_irq()
> > - Update KConfig description
> >
> > 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 | 7 +
> > drivers/media/platform/xilinx/Makefile | 1 +
> > .../media/platform/xilinx/xilinx-csi2rxss.c | 1157 +++++++++++++++++
> > 3 files changed, 1165 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..daed0b78c54d 100644
> > --- a/drivers/media/platform/xilinx/Kconfig
> > +++ b/drivers/media/platform/xilinx/Kconfig
> > @@ -10,6 +10,13 @@ config VIDEO_XILINX
> >
> > if VIDEO_XILINX
> >
> > +config VIDEO_XILINX_CSI2RXSS
> > + tristate "Xilinx CSI-2 Rx Subsystem"
> > + help
> > + Driver for Xilinx MIPI CSI-2 Rx Subsystem. This is a V4L sub-device
> > + based driver that takes input from CSI-2 Tx source and converts
> > + it into an AXI4-Stream.
> > +
> > 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..6e726ed4b688
> > --- /dev/null
> > +++ b/drivers/media/platform/xilinx/xilinx-csi2rxss.c
> > @@ -0,0 +1,1157 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Driver for Xilinx MIPI CSI-2 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_ISR_ALLINTR_MASK (0xc07e3fff)
> > +
> > +/*
> > + * 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_SPKT_FIFO_DEPTH 31
> > +
> > +#define XCSI_VCXR_OFFSET 0x34
> > +#define XCSI_VCXR_VCERR GENMASK(23, 0)
> > +#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
> > +
> > +/* MIPI CSI-2 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)
> > +
> > +/**
> > + * 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)
> > +
> > +/*
> > + * This table provides a mapping between CSI-2 Data type
> > + * and media bus formats
> > + */
> > +static const u32 xcsi2dt_mbus_lut[][2] = {
> > + { XCSI_DT_YUV4228B, MEDIA_BUS_FMT_UYVY8_1X16 },
> > + { XCSI_DT_YUV42210B, MEDIA_BUS_FMT_UYVY10_1X20 },
> > + { XCSI_DT_RGB444, 0 },
>
> Doesn't this map to MEDIA_BUS_FMT_RGB444_1X12 ?
>
> > + { XCSI_DT_RGB555, 0 },
>
> For this one we indeed have no media bus code.
>
> > + { XCSI_DT_RGB565, 0 },
>
> MEDIA_BUS_FMT_RGB565_1X16 ?
>
> > + { XCSI_DT_RGB666, 0 },
>
> MEDIA_BUS_FMT_RGB666_1X18 ?
>
[Vishal Sagar]
No. As per Xilinx UG934 the data on the bus will be of RBG type.
All the above media bus formats have Red is LSB, Green in middle and Blue in MSB.
Hence the corresponding media bus formats for these DT types are set as 0.
Once a the new media bus formats are added to the kernel, this table can be updated.
I will send those too but I am not sure how to add the documentation for the same yet.
> > + { XCSI_DT_RGB888, MEDIA_BUS_FMT_RBG888_1X24 },
> > + { XCSI_DT_RAW6, 0 },
> > + { XCSI_DT_RAW7, 0 },
> > + { XCSI_DT_RAW8, MEDIA_BUS_FMT_SRGGB8_1X8 },
> > + { XCSI_DT_RAW8, MEDIA_BUS_FMT_SBGGR8_1X8 },
> > + { XCSI_DT_RAW8, MEDIA_BUS_FMT_SGBRG8_1X8 },
> > + { XCSI_DT_RAW8, MEDIA_BUS_FMT_SGRBG8_1X8 },
> > + { XCSI_DT_RAW10, MEDIA_BUS_FMT_SRGGB10_1X10 },
> > + { XCSI_DT_RAW10, MEDIA_BUS_FMT_SBGGR10_1X10 },
> > + { XCSI_DT_RAW10, MEDIA_BUS_FMT_SGBRG10_1X10 },
> > + { XCSI_DT_RAW10, MEDIA_BUS_FMT_SGRBG10_1X10 },
> > + { XCSI_DT_RAW12, MEDIA_BUS_FMT_SRGGB12_1X12 },
> > + { XCSI_DT_RAW12, MEDIA_BUS_FMT_SBGGR12_1X12 },
> > + { XCSI_DT_RAW12, MEDIA_BUS_FMT_SGBRG12_1X12 },
> > + { XCSI_DT_RAW12, MEDIA_BUS_FMT_SGRBG12_1X12 },
> > + { XCSI_DT_RAW16, MEDIA_BUS_FMT_SRGGB16_1X16 },
> > + { XCSI_DT_RAW16, MEDIA_BUS_FMT_SBGGR16_1X16 },
> > + { XCSI_DT_RAW16, MEDIA_BUS_FMT_SGBRG16_1X16 },
> > + { XCSI_DT_RAW16, MEDIA_BUS_FMT_SGRBG16_1X16 },
> > + { XCSI_DT_RAW20, 0 },
> > +};
> > +
> > +/*
> > + * struct xcsi2rxss_core - Core config of CSI-2 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 - CSI-2 Rx Subsystem device structure
> > + * @core: Core structure for MIPI CSI-2 Rx Subsystem
> > + * @subdev: The v4l2 subdev structure
> > + * @format: Active V4L2 formats on each pad
> > + * @default_format: Default V4L2 format
> > + * @rsubdev: Remote subdev connected to sink pad
> > + * @lock: mutex for accessing this structure
> > + * @pads: media pads
> > + * @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;
> > + struct v4l2_subdev *rsubdev;
> > + /* used to protect access to this struct */
> > + struct mutex lock;
> > + struct media_pad pads[XCSI_MEDIA_PADS];
> > + bool streaming;
> > +};
>
> As commented on v11, I would merge the two structures. I don't really see a
> benefit from keeping them separate, and it's not commonly done in drivers.
>
Ok. I will merge the two together in next version.
> > +
> > +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); }
> > +
> > +/*
> > + * This function returns the nth mbus for a data type.
> > + * Note that n starts from 1.
>
> Indices starting from 1 are less common, and can thus generate confusion. Is
> there a reason to not start at 0 ? Looking at the callers, most pass a hardcoded
> 1, and the only one that does not adds 1 to the value before passing it to the
> function.
>
> > + * In case of error, mbus code returned is 0.
> > + */
> > +static u32 xcsi2rxss_get_nth_mbus(u32 dt, u32 n) {
> > + u32 i, count = 0, mbus_code = 0;
> > + u32 size = ARRAY_SIZE(xcsi2dt_mbus_lut);
> > +
> > + for (i = 0; i < size && count < n; i++) {
> > + if (xcsi2dt_mbus_lut[i][0] == dt) {
> > + mbus_code = xcsi2dt_mbus_lut[i][1];
> > + count++;
> > + }
> > + }
> > +
> > + /* Remove this as mbus_code is init to 0 */
> > + if (i == size || count < n)
> > + mbus_code = 0;
> > +
> > + return mbus_code;
>
> You can simplify this:
>
> unsigned int i;
>
> for (i = 0; i < ARRAY_SIZE(xcsi2dt_mbus_lut); i++) {
> if (xcsi2dt_mbus_lut[i][0] == dt) {
> if (n-- == 0)
> return xcsi2dt_mbus_lut[i][1];
> }
> }
>
> return 0;
>
Yes this is better. I will implement this in next version.
> > +}
> > +
> > +/* This returns the data type for a media bus format else 0 */ static
> > +u32 xcsi2rxss_get_dt(u32 mbus) {
> > + u32 i, size = ARRAY_SIZE(xcsi2dt_mbus_lut);
> > +
> > + for (i = 0; i < size; i++) {
>
> for (i = 0; i < ARRAY_SIZE(xcsi2dt_mbus_lut); i++) {
>
> and drop the size variable. The line is still under the 80 characters limit and
> makes it clearer what you iterate over.
>
Ok. I will remove the size variable.
> > + if (xcsi2dt_mbus_lut[i][1] == mbus)
> > + return xcsi2dt_mbus_lut[i][0];
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +/**
> > + * xcsi2rxss_soft_reset - Does a soft reset of the MIPI CSI-2 Rx
> > +Subsystem
> > + * @core: Core Xilinx CSI-2 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_soft_reset(struct xcsi2rxss_core *core) {
> > + u32 timeout = XCSI_TIMEOUT_VAL;
>
> I would hardcode 1000 here, otherwise we have to look up to find the value.
> Using a macro doesn't make the code more readable here.
>
Ok. I will update it in next version.
> > +
> > + 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_hard_reset(struct xcsi2rxss_core *core, u8
> > +sleep) {
> > + if (!core->rst_gpio)
> > + return;
> > +
> > + /* minimum of 40 dphy_clk_200M cycles */
> > + if (sleep) {
> > + gpiod_set_value_cansleep(core->rst_gpio, 1);
> > + usleep_range(1, 2);
> > + gpiod_set_value_cansleep(core->rst_gpio, 0);
> > + } else {
> > + /* this is for interrupt context */
> > + gpiod_set_value(core->rst_gpio, 1);
> > + ndelay(250);
> > + gpiod_set_value(core->rst_gpio, 0);
>
> We should really minimize the time taken during interrupts. Do we really need
> to reset the hardware in the interrupt handler, can't we just flag the error and
> reset it at streamoff time for instance ?
>
Yes that is also a possibility. I will removed the "else ndelay" part.
> > + }
> > +}
> > +
> > +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;
> > + struct device *dev = core->dev;
> > + unsigned int i;
> > +
> > + for (i = 0; i < XCSI_NUM_EVENTS; i++) {
> > + if (core->events[i] > 0) {
> > + dev_info(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(dev,
> > + "VC %d Frame %s err vcx events:
> %d\n",
> > + (i / 2) + XCSI_VCX_START,
> > + i & 1 ? "Sync" : "Level",
> > + core->vcx_events[i]);
> > + }
> > + }
> > + }
> > +}
> > +
> > +/**
> > + * 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
> > + */
>
> I didn't mention it in the review of v11, but I like how detailed the logging is.
> I've worked with several CSI-2 receivers in the past whose drivers provided
> very little status feedback, and it made debugging hard. This is really nice,
> good work :-)
>
Thanks for noting this and the appreciation! ð
> > +static int xcsi2rxss_log_status(struct v4l2_subdev *sd) {
> > + struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
> > + struct xcsi2rxss_core *core = &xcsi2rxss->core;
> > + struct device *dev = core->dev;
> > + const char *tr = "true";
> > + const char *fa = "false";
> > + u32 reg, data;
> > + unsigned int i, max_vc;
> > +
> > + mutex_lock(&xcsi2rxss->lock);
> > +
> > + xcsi2rxss_log_counters(xcsi2rxss);
> > +
> > + dev_info(dev, "***** Core Status *****\n");
> > + data = xcsi2rxss_read(core, XCSI_CSR_OFFSET);
> > + dev_info(dev, "Short Packet FIFO Full = %s\n",
> > + data & XCSI_CSR_SPFIFOFULL ? tr : fa);
> > + dev_info(dev, "Short Packet FIFO Not Empty = %s\n",
> > + data & XCSI_CSR_SPFIFONE ? tr : fa);
> > + dev_info(dev, "Stream line buffer full = %s\n",
> > + data & XCSI_CSR_SLBF ? tr : fa);
> > + dev_info(dev, "Soft reset/Core disable in progress = %s\n",
> > + data & XCSI_CSR_RIPCD ? tr : fa);
> > +
> > + /* Clk & Lane Info */
> > + dev_info(dev, "******** Clock Lane Info *********\n");
> > + data = xcsi2rxss_read(core, XCSI_CLKINFR_OFFSET);
> > + dev_info(dev, "Clock Lane in Stop State = %s\n",
> > + data & XCSI_CLKINFR_STOP ? tr : fa);
> > +
> > + dev_info(dev, "******** Data Lane Info *********\n");
> > + dev_info(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(dev, "%d\t%s\t\t%s\t\t%s\n", i,
> > + data & XCSI_DLXINFR_SOTERR ? tr : fa,
> > + data & XCSI_DLXINFR_SOTSYNCERR ? tr : fa,
> > + data & XCSI_DLXINFR_STOP ? tr : fa);
> > +
> > + reg += XCSI_NEXTREG_OFFSET;
> > + }
> > +
> > + /* Virtual Channel Image Information */
> > + dev_info(dev, "********** Virtual Channel Info ************\n");
> > + dev_info(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(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;
> > + int ret = 0;
> > +
> > + /* enable core */
> > + xcsi2rxss_set(core, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
> > +
> > + ret = xcsi2rxss_soft_reset(core);
> > + if (ret < 0) {
> > + state->streaming = false;
> > + return ret;
> > + }
> > +
> > + /* enable interrupts */
> > + 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);
> > +
> > + state->streaming = true;
> > +
> > + state->rsubdev =
> > + xcsi2rxss_get_remote_subdev(&state->pads[XVIP_PAD_SINK]);
> > +
> > + ret = v4l2_subdev_call(state->rsubdev, video, s_stream, 1);
> > + if (ret) {
> > + /* disable interrupts */
> > + xcsi2rxss_clr(core, XCSI_IER_OFFSET, XCSI_IER_INTR_MASK);
> > + xcsi2rxss_clr(core, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
> > +
> > + /* disable core */
> > + xcsi2rxss_clr(core, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
> > + state->streaming = false;
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static void xcsi2rxss_stop_stream(struct xcsi2rxss_state *state) {
> > + struct xcsi2rxss_core *core = &state->core;
> > +
> > + v4l2_subdev_call(state->rsubdev, video, s_stream, 0);
> > +
> > + /* disable interrupts */
> > + xcsi2rxss_clr(core, XCSI_IER_OFFSET, XCSI_IER_INTR_MASK);
> > + xcsi2rxss_clr(core, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
> > +
> > + /* disable core */
> > + xcsi2rxss_clr(core, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
> > + state->streaming = false;
> > +}
> > +
> > +/**
> > + * xcsi2rxss_irq_handler - Interrupt handler for CSI-2
> > + * @irq: IRQ number
> > + * @data: 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 */ static
> > +irqreturn_t xcsi2rxss_irq_handler(int irq, void *data) {
> > + struct xcsi2rxss_state *state = (struct xcsi2rxss_state *)data;
> > + struct xcsi2rxss_core *core = &state->core;
> > + struct device *dev = core->dev;
> > + u32 status;
> > +
> > + status = xcsi2rxss_read(core, XCSI_ISR_OFFSET) &
> XCSI_ISR_ALLINTR_MASK;
> > + xcsi2rxss_write(core, XCSI_ISR_OFFSET, status);
> > +
> > + /* Received a short packet */
> > + if (status & XCSI_ISR_SPFIFONE) {
> > + u32 count = 0;
> > +
> > + /*
> > + * Drain generic short packet FIFO by reading max 31
> > + * (fifo depth) short packets from fifo or till fifo is empty.
> > + */
>
> Thanks for the explanation in a reply to v11 that this is generic short packets,
> and won't cover FS/FE for instance. I had missed that.
>
> > + while (count < XCSI_SPKT_FIFO_DEPTH) {
>
> for (count = 0; count < XCSI_SPKT_FIFO_DEPTH; ++count) {
>
> > + u32 spfifostat;
> > +
> > + dev_dbg(dev, "Short packet = 0x%08x\n",
> > + xcsi2rxss_read(core, XCSI_SPKTR_OFFSET));
>
> If the kernel is compiled without dynamic debug enabled, and if DEBUG isn't
> defined, this line will be compiled out, and XCSI_SPKTR_OFFSET will never be
> read.
Good catch. I will update this in next version based on your logic below.
>
> u32 packet = xcsi2rxss_read(core,
> XCSI_SPKTR_OFFSET);
> dev_dbg(dev, "Short packet = 0x%08x\n", packet);
>
> > + count++;
>
> And you can drop this.
>
> > + spfifostat = xcsi2rxss_read(core, XCSI_ISR_OFFSET);
> > + spfifostat &= XCSI_ISR_SPFIFONE;
> > + if (!spfifostat)
> > + break;
> > + xcsi2rxss_write(core, XCSI_ISR_OFFSET, spfifostat);
> > + }
> > + }
> > +
> > + /* Short packet FIFO overflow */
> > + if (status & XCSI_ISR_SPFIFOF)
> > + dev_dbg_ratelimited(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(dev, "Stream Line Buffer Full!\n");
> > +
> > + /* disable interrupts */
> > + xcsi2rxss_clr(core, XCSI_IER_OFFSET, XCSI_IER_INTR_MASK);
> > + xcsi2rxss_clr(core, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
> > +
> > + /* disable core */
> > + xcsi2rxss_clr(core, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
> > + state->streaming = false;
> > +
> > + /* use delay instead of sleep in irq context */
> > + xcsi2rxss_hard_reset(core, 0);
>
> As commented above, I wonder if we could move this line to streamoff.
>
Yes this can be moved to streamoff.
I am adding a comment here
/*
* The IP needs to be hard reset before it can be used now.
* This will be done in streamoff.
*/
> We will also need a mechanism to tell the downstream entities in the pipeline
> that an error occurs, so that video nodes can report errors to applications, but
> that can be done on top of this patch (and spans quite a few drivers). In this
> driver it should be fairly simple, it's a matter of calling v4l2_subdev_notify().
> We will however have to define an event type for this (I'm surprised that none
> exist already).
>
> How about adding
>
> /*
> * TODO: Notify the whole pipeline with v4l2_subdev_notify()
> to
> * inform userspace.
> */
>
> to make sure we don't forget ?
>
Sure. I will add this TODO.
Please note that earlier I had added an event v4l2_subdev_notify_event()
to notify the app but it was taken out in v10.
> > + }
> > +
> > + /* 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(dev, "%s: %u\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);
> > + }
> > + }
> > +
> > + 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 == xcsi2rxss->streaming)
> > + goto stream_done;
> > +
> > + if (enable && !xcsi2rxss->streaming) {
>
> You can make this
>
> if (enable) {
>
> as the second part has been check just before.
>
Thanks for the suggestion. I will make the change in next version.
> > + xcsi2rxss_reset_event_counters(xcsi2rxss);
> > + ret = xcsi2rxss_start_stream(xcsi2rxss);
> > + } else {
> > + xcsi2rxss_stop_stream(xcsi2rxss);
> > + xcsi2rxss_hard_reset(&xcsi2rxss->core, 1);
> > + }
> > +
> > +stream_done:
> > + 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_init_cfg - Initialise the pad format config to default
> > + * @sd: Pointer to V4L2 Sub device structure
> > + * @cfg: Pointer to sub device pad information structure
> > + *
> > + * This function is used to initialize the pad format with the
> > +default
> > + * values.
> > + *
> > + * Return: 0 on success
> > + */
> > +static int xcsi2rxss_init_cfg(struct v4l2_subdev *sd,
> > + struct v4l2_subdev_pad_config *cfg) {
> > + struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
> > + struct v4l2_mbus_framefmt *format;
> > + unsigned int i;
> > +
> > + mutex_lock(&xcsi2rxss->lock);
> > + for (i = 0; i < XCSI_MEDIA_PADS; i++) {
> > + format = v4l2_subdev_get_try_format(sd, cfg, i);
> > + *format = xcsi2rxss->default_format;
> > + }
> > + mutex_unlock(&xcsi2rxss->lock);
> > +
> > + return 0;
> > +}
> > +
> > +/**
> > + * 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;
> > + u32 dt;
> > +
> > + /* 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.
> > + */
> > + dt = xcsi2rxss_get_dt(fmt->format.code);
>
> For a second I thought this was dealing with device tree ;-)
>
> > + if (!(dt == core->datatype ||
> > + 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)) {
>
> Can't this be simplified to
>
> if (dt != core->datatype && dt != XCSI_DT_RAW8) {
>
> ?
>
Yes this is concise. I will use this in next version.
> > + dev_dbg(core->dev, "Unsupported media bus format");
> > + /* set the default format for the data type */
> > + fmt->format.code = xcsi2rxss_get_nth_mbus(core->datatype,
> 1);
> > + }
> > +
> > + *__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);
> > + u32 dt, n;
> > + int ret = 0;
> > +
> > + /* RAW8 dt packets are available in all DT configurations */
> > + /* n starts from 1 */
> > + if (code->index < 4) {
> > + n = code->index + 1;
> > + dt = XCSI_DT_RAW8;
> > + } else {
> > + n = code->index - 4 + 1;
> > + dt = state->core.datatype;
> > + }
>
> If state->core.datatype == XCSI_DT_RAW8 then you will enumerate the
> formats twice. You could to
>
> if (code->index < 4) {
> n = code->index + 1;
> dt = XCSI_DT_RAW8;
> } else if (state->core.datatype != XCSI_DT_RAW8) {{
> n = code->index - 4 + 1;
> dt = state->core.datatype;
> } else {
> return -EINVAL;
> }
>
Thanks for catching this. I will update this in next version.
I will remove the + 1 now as this will be fixed in the get_nth_mbus() as described above.
> > +
> > + code->code = xcsi2rxss_get_nth_mbus(dt, n);
> > + if (!code->code)
> > + ret = -EINVAL;
> > +
> > + return ret;
> > +}
> > +
> > +/*
> > +---------------------------------------------------------------------
> > +--------
> > + * 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 = {
> > + .init_cfg = xcsi2rxss_init_cfg,
> > + .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 void xcsi2rxss_set_default_format(struct xcsi2rxss_state
> > +*state) {
> > + struct xcsi2rxss_core *core = &state->core;
> > +
> > + state->default_format.code = xcsi2rxss_get_nth_mbus(core-
> >datatype, 1);
> > + 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; }
> > +
> > +static int xcsi2rxss_parse_of(struct xcsi2rxss_state *xcsi2rxss) {
> > + struct xcsi2rxss_core *core = &xcsi2rxss->core;
> > + struct device *dev = core->dev;
> > + struct device_node *node = dev->of_node;
> > +
> > + struct fwnode_handle *ep;
> > + struct v4l2_fwnode_endpoint vep = {
> > + .bus_type = V4L2_MBUS_CSI2_DPHY
> > + };
> > + 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(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(dev, "enable csi v2 for this pixel format");
> > + }
> > + break;
> > + default:
> > + ret = -EINVAL;
> > + }
> > + if (ret < 0) {
> > + dev_err(dev, "invalid csi-pxl-format property!\n");
> > + return ret;
> > + }
> > +
> > + vfb = of_property_read_bool(node, "xlnx,vfb");
> > + if (!vfb) {
> > + dev_err(dev, "operation without VFB is not supported\n");
> > + return -EINVAL;
> > + }
> > +
> > + ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
> > + XVIP_PAD_SINK, 0,
> > +
> FWNODE_GRAPH_ENDPOINT_NEXT);
> > + if (!ep) {
> > + dev_err(dev, "no sink port found");
> > + return -EINVAL;
> > + }
> > +
> > + ret = v4l2_fwnode_endpoint_parse(ep, &vep);
> > + fwnode_handle_put(ep);
> > + if (ret) {
> > + dev_err(dev, "error parsing sink port");
> > + return ret;
> > + }
> > +
> > + dev_dbg(dev, "base.port = %d base.id = %d\n", vep.base.port,
> > + vep.base.id);
>
> Here vep.base.port will always be XVIP_PAD_SINK and vep.base.id will always
> be 0, right ? Is the debug message needed if it always prints the same value ?
>
Yes not needed. I will remove this in next version.
> > + dev_dbg(dev, "mipi number lanes = %d\n",
> > + vep.bus.mipi_csi2.num_data_lanes);
> > +
> > + core->max_num_lanes = vep.bus.mipi_csi2.num_data_lanes;
> > +
> > + ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
> > + XVIP_PAD_SOURCE, 0,
> > +
> FWNODE_GRAPH_ENDPOINT_NEXT);
> > + if (!ep) {
> > + dev_err(dev, "no source port found");
> > + return -EINVAL;
> > + }
> > +
> > + fwnode_handle_put(ep);
> > +
> > + dev_dbg(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);
> > +
> > + return 0;
> > +}
> > +
> > +static int xcsi2rxss_probe(struct platform_device *pdev) {
> > + struct v4l2_subdev *subdev;
> > + struct xcsi2rxss_state *xcsi2rxss;
> > + struct xcsi2rxss_core *core;
> > + int num_clks = ARRAY_SIZE(xcsi2rxss_clks);
> > + struct device *dev = &pdev->dev;
> > + int irq, ret;
> > +
> > + xcsi2rxss = devm_kzalloc(dev, sizeof(*xcsi2rxss), GFP_KERNEL);
> > + if (!xcsi2rxss)
> > + return -ENOMEM;
> > +
> > + core = &xcsi2rxss->core;
> > + core->dev = dev;
> > +
> > + core->clks = devm_kmemdup(dev, xcsi2rxss_clks,
> > + sizeof(xcsi2rxss_clks), GFP_KERNEL);
> > + if (!core->clks)
> > + return -ENOMEM;
> > +
> > + /* Reset GPIO */
> > + core->rst_gpio = devm_gpiod_get_optional(dev, "video-reset",
> > + GPIOD_OUT_HIGH);
> > + if (IS_ERR(core->rst_gpio)) {
> > + if (PTR_ERR(core->rst_gpio) != -EPROBE_DEFER)
> > + dev_err(dev, "Video Reset GPIO not setup in DT");
> > + return PTR_ERR(core->rst_gpio);
> > + }
> > +
> > + ret = xcsi2rxss_parse_of(xcsi2rxss);
> > + if (ret < 0)
> > + return ret;
> > +
> > + core->iomem = devm_platform_ioremap_resource(pdev, 0);
> > + if (IS_ERR(core->iomem))
> > + return PTR_ERR(core->iomem);
> > +
> > + irq = platform_get_irq(pdev, 0);
> > + if (irq < 0)
> > + return irq;
> > +
> > + ret = devm_request_threaded_irq(dev, irq, NULL,
> > + xcsi2rxss_irq_handler,
> IRQF_ONESHOT,
> > + dev_name(dev), xcsi2rxss);
> > + if (ret) {
> > + dev_err(dev, "Err = %d Interrupt handler reg failed!\n", ret);
> > + return ret;
> > + }
> > +
> > + ret = clk_bulk_get(dev, num_clks, core->clks);
> > + if (ret)
> > + return ret;
> > +
>
> I agree that we can start with this and then improve clock enable/disable, but
> how about adding
>
> /* TODO: Enable/disable clocks at stream on/off time. */
>
> to make sure we won't forget ?
>
Ok. I will add this TODO in next version.
> > + ret = clk_bulk_prepare_enable(num_clks, core->clks);
> > + if (ret)
> > + goto err_clk_put;
> > +
> > + mutex_init(&xcsi2rxss->lock);
> > +
> > + xcsi2rxss_hard_reset(core, 1);
> > +
> > + xcsi2rxss_soft_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);
> > + xcsi2rxss->format = xcsi2rxss->default_format;
> > +
> > + /* Initialize V4L2 subdevice and media entity */
> > + subdev = &xcsi2rxss->subdev;
> > + v4l2_subdev_init(subdev, &xcsi2rxss_ops);
> > + subdev->dev = dev;
> > + strscpy(subdev->name, dev_name(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(dev, "failed to register subdev\n");
> > + goto error;
> > + }
> > +
> > + dev_info(dev, "probe success\n");
>
> We tend to avoid messages when probe succeeds, as that would really flood
> the kernel log (and increase the boot time when the console is output on a
> serial port) if all driver did so.
>
I see some drivers having this hence added it. I will remove this in next version.
> Very nice work, all the comments are minor. I trust that you'll get the small
> changes right, so please add
>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
>
> to the next version (of course if there's something you're not sure about,
> please let me know first).
>
Thanks for giving the green light to this.
My only concern is w.r.t to the media bus formats comments raised at the top of this review.
If it is ok, I will send out the v13 adding your "Reviewed-by" tag.
> > +
> > + return 0;
> > +error:
> > + media_entity_cleanup(&subdev->entity);
> > + mutex_destroy(&xcsi2rxss->lock);
> > + 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 CSI-2 Rx Subsystem Driver");
> > +MODULE_LICENSE("GPL v2");
>
> --
> Regards,
>
> Laurent Pinchart
Regards
Vishal Sagar