Re: [PATCH v3 2/3] media: atmel: introduce microchip csi2dc driver

From: Sakari Ailus
Date: Fri Oct 09 2020 - 10:59:18 EST


Hi Eugen,

My apologies for the late reply.

On Mon, Sep 07, 2020 at 09:16:57AM +0000, Eugen.Hristev@xxxxxxxxxxxxx wrote:
> On 31.08.2020 11:50, Sakari Ailus wrote:
>
> > Hi Eugen,
> >
> > Thanks for the update.
>
> Hi Sakari,
>
> Thanks for reviewing, but, could you please help me understand your
> review below ?
>
> >
> > On Wed, Aug 26, 2020 at 09:51:41AM +0300, Eugen Hristev wrote:
> >> Microchip CSI2DC (CSI2 Demultiplexer Controller) is a misc bridge device
> >> that converts a byte stream in IDI Synopsys format (coming from a CSI2HOST)
> >> to a pixel stream that can be captured by a sensor controller.
> >>
> >> Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
> >> ---
> >> Changes in v2:
> >> - moved driver to platform/atmel
> >> - fixed minor things as per Sakari's review
> >> - still some things from v2 review are not yet addressed, to be followed up
> >>
> >> drivers/media/platform/atmel/Kconfig | 13 +
> >> drivers/media/platform/atmel/Makefile | 1 +
> >> .../media/platform/atmel/microchip-csi2dc.c | 700 ++++++++++++++++++
> >> 3 files changed, 714 insertions(+)
> >> create mode 100644 drivers/media/platform/atmel/microchip-csi2dc.c
> >>
> >> diff --git a/drivers/media/platform/atmel/Kconfig b/drivers/media/platform/atmel/Kconfig
> >> index 1850fe7f9360..80bbddcc2504 100644
> >> --- a/drivers/media/platform/atmel/Kconfig
> >> +++ b/drivers/media/platform/atmel/Kconfig
> >> @@ -21,3 +21,16 @@ config VIDEO_ATMEL_ISI
> >> help
> >> This module makes the ATMEL Image Sensor Interface available
> >> as a v4l2 device.
> >> +
> >> +config VIDEO_MICROCHIP_CSI2DC
> >> + tristate "Microchip CSI2 Demux Controller"
> >> + depends on VIDEO_V4L2 && COMMON_CLK && OF
> >> + depends on ARCH_AT91 || COMPILE_TEST
> >> + select MEDIA_CONTROLLER
> >> + select VIDEO_V4L2_SUBDEV_API
> >> + select V4L2_FWNODE
> >> + help
> >> + CSI2 Demux Controller driver. CSI2DC is a helper chip
> >> + that converts IDI interface byte stream to a parallel pixel stream.
> >> + It supports various RAW formats as input.
> >> + Performs clock domain crossing between hardware blocks.
> >> diff --git a/drivers/media/platform/atmel/Makefile b/drivers/media/platform/atmel/Makefile
> >> index 2dba38994a70..8af7c5b534c3 100644
> >> --- a/drivers/media/platform/atmel/Makefile
> >> +++ b/drivers/media/platform/atmel/Makefile
> >> @@ -3,3 +3,4 @@ atmel-isc-objs = atmel-sama5d2-isc.o atmel-isc-base.o
> >>
> >> obj-$(CONFIG_VIDEO_ATMEL_ISI) += atmel-isi.o
> >> obj-$(CONFIG_VIDEO_ATMEL_ISC) += atmel-isc.o
> >> +obj-$(CONFIG_VIDEO_MICROCHIP_CSI2DC) += microchip-csi2dc.o
> >> diff --git a/drivers/media/platform/atmel/microchip-csi2dc.c b/drivers/media/platform/atmel/microchip-csi2dc.c
> >> new file mode 100644
> >> index 000000000000..97d07a80bbf7
> >> --- /dev/null
> >> +++ b/drivers/media/platform/atmel/microchip-csi2dc.c
> >> @@ -0,0 +1,700 @@
> >> +// SPDX-License-Identifier: GPL-2.0
> >> +/*
> >> + * Microchip CSI2 Demux Controller (CSI2DC) driver
> >> + *
> >> + * Copyright (C) 2018-2020 Microchip Technology, Inc.
> >> + *
> >> + * Author: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
> >> + *
> >> + */
> >> +
> >> +#include <linux/clk.h>
> >> +#include <linux/module.h>
> >> +#include <linux/of.h>
> >> +#include <linux/of_graph.h>
> >> +#include <linux/platform_device.h>
> >> +#include <linux/pm_runtime.h>
> >> +#include <linux/videodev2.h>
> >> +
> >> +#include <media/v4l2-device.h>
> >> +#include <media/v4l2-fwnode.h>
> >> +#include <media/v4l2-subdev.h>
> >> +#include <media/videobuf2-dma-contig.h>
> >> +
> >> +/* Global configuration register */
> >> +#define CSI2DC_GCFG 0x0
> >> +
> >> +/* MIPI sensor pixel clock is free running */
> >> +#define CSI2DC_GCFG_MIPIFRN BIT(0)
> >> +/* Output waveform inter-line minimum delay */
> >> +#define CSI2DC_GCFG_HLC(v) ((v) << 4)
> >> +#define CSI2DC_GCFG_HLC_MASK GENMASK(7, 4)
> >> +
> >> +/* Global control register */
> >> +#define CSI2DC_GCTLR 0x04
> >> +#define CSI2DC_GCTLR_SWRST BIT(0)
> >> +
> >> +/* Global status register */
> >> +#define CSI2DC_GS 0x08
> >> +
> >> +/* SSP interrupt status register */
> >> +#define CSI2DC_SSPIS 0x28
> >> +/* Pipe update register */
> >> +#define CSI2DC_PU 0xC0
> >> +/* Video pipe attributes update */
> >> +#define CSI2DC_PU_VP BIT(0)
> >> +
> >> +/* Pipe update status register */
> >> +#define CSI2DC_PUS 0xC4
> >> +
> >> +/* Video pipeline enable register */
> >> +#define CSI2DC_VPE 0xF8
> >> +#define CSI2DC_VPE_ENABLE BIT(0)
> >> +
> >> +/* Video pipeline configuration register */
> >> +#define CSI2DC_VPCFG 0xFC
> >> +/* Data type */
> >> +#define CSI2DC_VPCFG_DT(v) ((v) << 0)
> >> +#define CSI2DC_VPCFG_DT_MASK GENMASK(5, 0)
> >> +/* Virtual channel identifier */
> >> +#define CSI2DC_VPCFG_VC(v) ((v) << 6)
> >> +#define CSI2DC_VPCFG_VC_MASK GENMASK(7, 6)
> >> +/* Decompression enable */
> >> +#define CSI2DC_VPCFG_DE BIT(8)
> >> +/* Decoder mode */
> >> +#define CSI2DC_VPCFG_DM(v) ((v) << 9)
> >> +#define CSI2DC_VPCFG_DM_DECODER8TO12 0
> >> +/* Decoder predictor 2 selection */
> >> +#define CSI2DC_VPCFG_DP2 BIT(12)
> >> +/* Recommended memory storage */
> >> +#define CSI2DC_VPCFG_RMS BIT(13)
> >> +/* Post adjustment */
> >> +#define CSI2DC_VPCFG_PA BIT(14)
> >> +
> >> +/* Video pipeline column register */
> >> +#define CSI2DC_VPCOL 0x100
> >> +/* Column number */
> >> +#define CSI2DC_VPCOL_COL(v) ((v) << 0)
> >> +#define CSI2DC_VPCOL_COL_MASK GENMASK(15, 0)
> >> +
> >> +/* Video pipeline row register */
> >> +#define CSI2DC_VPROW 0x104
> >> +/* Row number */
> >> +#define CSI2DC_VPROW_ROW(v) ((v) << 0)
> >> +#define CSI2DC_VPROW_ROW_MASK GENMASK(15, 0)
> >> +
> >> +/* Version register */
> >> +#define CSI2DC_VERSION 0x1FC
> >> +
> >> +/* register read/write helpers */
> >> +#define csi2dc_readl(st, reg) readl_relaxed((st)->base + (reg))
> >> +#define csi2dc_writel(st, reg, val) writel_relaxed((val), (st)->base + (reg))
> >> +
> >> +/* supported RAW data types */
> >> +#define CSI2DC_DT_RAW6 0x28
> >> +#define CSI2DC_DT_RAW7 0x29
> >> +#define CSI2DC_DT_RAW8 0x2A
> >> +#define CSI2DC_DT_RAW10 0x2B
> >> +#define CSI2DC_DT_RAW12 0x2C
> >> +#define CSI2DC_DT_RAW14 0x2D
> >> +
> >> +struct csi2dc_format {
> >> + u32 mbus_code;
> >> + u32 dt;
> >> +};
> >> +
> >> +static struct csi2dc_format csi2dc_formats_list[] = {
> >
> > const
>
> Elements from this array are being selected in a dynamic list, and
> pointed from a non-const array of selected working formats (at subdevice
> completion time). If I make this const , I will get compiler warnings
> when assigning to the non-const array.
> What solution do you suggest for this ?

You'll need to make the other instances const, too. They do not need to be
modified I presume?

>
>
> >
> >> + {
> >> + .mbus_code = MEDIA_BUS_FMT_SRGGB10_1X10,
> >> + .dt = CSI2DC_DT_RAW10,
> >> + },
> >> +};
> >> +
> >> +enum mipi_csi_pads {
> >> + CSI2DC_PAD_SINK = 0,
> >> + CSI2DC_PAD_SOURCE = 1,
> >> + CSI2DC_PADS_NUM = 2,
> >> +};
> >> +
> >> +struct csi2dc_device {
> >> + void __iomem *base;
> >> + struct v4l2_subdev csi2dc_sd;
> >> + struct device *dev;
> >> + struct v4l2_device v4l2_dev;
> >
> > This device is a bridge; the V4L2 device should be registered by the master
> > driver, i.e. the one handling DMA and registering the video nodes. Please
> > drop this.
> >
> >> + struct clk *pclk;
> >> + struct clk *scck;
> >> +
> >> + bool video_pipe;
> >> +
> >> + u32 num_fmts;
> >> + struct csi2dc_format **formats;
> >> +
> >> + struct csi2dc_format *cur_fmt;
> >> + struct csi2dc_format *try_fmt;
> >> +
> >> + struct media_pad pads[CSI2DC_PADS_NUM];
> >> +
> >> + bool clk_gated;
> >> + u32 inter_line_delay;
> >> + u32 vc;
> >> +
> >> + struct v4l2_async_subdev *asd;
> >> + struct v4l2_async_notifier notifier;
> >> +
> >> + struct v4l2_subdev *input_sd;
> >> + bool completed;
> >> +};
> >> +
> >> +static void csi2dc_vp_update(struct csi2dc_device *csi2dc)
> >> +{
> >> + u32 vp;
> >> +
> >> + vp = CSI2DC_VPCFG_DT(csi2dc->cur_fmt->dt) & CSI2DC_VPCFG_DT_MASK;
> >> + vp |= CSI2DC_VPCFG_VC(csi2dc->vc) & CSI2DC_VPCFG_VC_MASK;
> >> + vp &= ~CSI2DC_VPCFG_DE;
> >> + vp |= CSI2DC_VPCFG_DM(CSI2DC_VPCFG_DM_DECODER8TO12);
> >> + vp &= ~CSI2DC_VPCFG_DP2;
> >> + vp &= ~CSI2DC_VPCFG_RMS;
> >> + vp |= CSI2DC_VPCFG_PA;
> >> +
> >> + csi2dc_writel(csi2dc, CSI2DC_VPCFG, vp);
> >> + csi2dc_writel(csi2dc, CSI2DC_VPE, CSI2DC_VPE_ENABLE);
> >> + csi2dc_writel(csi2dc, CSI2DC_PU, CSI2DC_PU_VP);
> >> +}
> >> +
> >> +static inline struct csi2dc_device *
> >> +csi2dc_sd_to_csi2dc_device(struct v4l2_subdev *csi2dc_sd)
> >> +{
> >> + return container_of(csi2dc_sd, struct csi2dc_device, csi2dc_sd);
> >> +}
> >> +
> >> +static int csi2dc_enum_mbus_code(struct v4l2_subdev *csi2dc_sd,
> >> + struct v4l2_subdev_pad_config *cfg,
> >> + struct v4l2_subdev_mbus_code_enum *code)
> >> +{
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> +
> >> + if (code->index >= csi2dc->num_fmts)
> >> + return -EINVAL;
> >> +
> >> + code->code = csi2dc->formats[code->index]->mbus_code;
> >> + return 0;
> >> +}
> >> +
> >> +static int csi2dc_try_fmt(struct v4l2_subdev *csi2dc_sd,
> >> + struct v4l2_subdev_pad_config *cfg,
> >> + struct v4l2_subdev_format *req_fmt)
> >> +{
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> + struct csi2dc_format *fmt;
> >> +
> >> + if (!csi2dc->completed) {
> >> + dev_dbg((csi2dc)->dev, "subdev not registered yet\n");
> >> + return 0;
> >> + }
> >> +
> >> + for (fmt = csi2dc->formats[0]; fmt; fmt++)
> >> + if (req_fmt->format.code == fmt->mbus_code)
> >> + csi2dc->try_fmt = fmt;
> >> +
> >> + /* in case we could not find the desired format, default to something */
> >> + if (!csi2dc->try_fmt ||
> >> + req_fmt->format.code != csi2dc->try_fmt->mbus_code) {
> >> + csi2dc->try_fmt = csi2dc->formats[0];
> >> + req_fmt->format.code = csi2dc->formats[0]->mbus_code;
> >> + }
> >> +
> >> + return v4l2_subdev_call(csi2dc->input_sd, pad, set_fmt, cfg, req_fmt);
> >> +}
> >> +
> >> +static int csi2dc_set_fmt(struct v4l2_subdev *csi2dc_sd,
> >> + struct v4l2_subdev_pad_config *cfg,
> >> + struct v4l2_subdev_format *req_fmt)
> >> +{
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> + int ret;
> >> +
> >> + if (!csi2dc->completed) {
> >> + dev_dbg((csi2dc)->dev, "subdev not registered yet\n");
> >> + return 0;
> >> + }
> >> +
> >> + csi2dc_try_fmt(csi2dc_sd, cfg, req_fmt);
> >> +
> >> + if (csi2dc->try_fmt->mbus_code != req_fmt->format.code) {
> >> + dev_dbg(csi2dc->dev, "CSI2DC unsupported format 0x%x\n",
> >> + req_fmt->format.code);
> >
> > Please adjust the format into a supported one instead.
>
> I thought that only the 'try_fmt' calls should adapt to something that
> works. It is the same case for set_fmt ? This function cannot return
> invalid format ?

Correct. set_fmt should always return with a valid format.

Perhaps merging csi2dc_try_fmt() to this function would help? It's not used
elsewhere. It seems you're doing some redundant checks here, too.

> >
> >> + return -EINVAL;
> >> + }
> >> +
> >> + ret = v4l2_subdev_call(csi2dc->input_sd, pad, set_fmt, cfg, req_fmt);
> >> + if (ret) {
> >> + dev_err(csi2dc->dev, "input subdev failed %d\n", ret);
> >> + return ret;
> >> + }
> >> +
> >> + csi2dc->cur_fmt = csi2dc->try_fmt;
> >> + /* update video pipe */
> >> + csi2dc_vp_update(csi2dc);
> >> +
> >> + dev_dbg(csi2dc->dev, "CSI2DC new format: 0x%x\n", req_fmt->format.code);
> >> + return 0;
> >> +}
> >> +
> >> +static int csi2dc_formats_init(struct csi2dc_device *csi2dc)
> >> +{
> >> + int i, j;
> >> + struct csi2dc_format *fmt = &csi2dc_formats_list[0];
> >> +
> >> + csi2dc->num_fmts = 1;
> >> +
> >> + csi2dc->formats = devm_kcalloc(csi2dc->dev, csi2dc->num_fmts,
> >> + sizeof(*csi2dc->formats), GFP_KERNEL);
> >> +
> >> + for (i = 0, j = 0; i < ARRAY_SIZE(csi2dc_formats_list); i++, fmt++)
> >> + if (fmt->mbus_code == MEDIA_BUS_FMT_SRGGB10_1X10)
> >> + csi2dc->formats[j++] = fmt;
> >> + return 0;
> >> +}
> >> +
> >> +static int csi2dc_s_power(struct v4l2_subdev *csi2dc_sd, int on)
> >> +{
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> + int ret = 0;
> >> +
> >> + if (!csi2dc->completed) {
> >> + dev_dbg((csi2dc)->dev, "subdev not registered yet\n");
> >> + return 0;
> >> + }
> >> +
> >> + if (on)
> >> + ret = clk_prepare_enable(csi2dc->scck);
> >> + else
> >> + clk_disable_unprepare(csi2dc->scck);
> >> + if (ret)
> >> + dev_err(csi2dc->dev, "failed to enable scck: %d\n", ret);
> >> +
> >> + /* if powering up, deassert reset line */
> >> + if (on)
> >> + csi2dc_writel(csi2dc, CSI2DC_GCTLR, CSI2DC_GCTLR_SWRST);
> >> +
> >> + ret = v4l2_subdev_call(csi2dc->input_sd, core, s_power, on);
> >> +
> >> + /* if powering down, assert reset line */
> >> + if (!on)
> >> + csi2dc_writel(csi2dc, CSI2DC_GCTLR, !CSI2DC_GCTLR_SWRST);
> >
> > These go to the runtime resume and suspend callbacks.
>
> Okay I will update
>
> >
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static int csi2dc_s_stream(struct v4l2_subdev *csi2dc_sd, int enable)
> >> +{
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> +
> >> + if (!csi2dc->completed) {
> >> + dev_dbg((csi2dc)->dev, "subdev not registered yet\n");
> >> + return 0;
> >> + }
> >> +
> >> + return v4l2_subdev_call(csi2dc->input_sd, video, s_stream, enable);
> >> +}
> >> +
> >> +static int csi2dc_g_frame_interval(struct v4l2_subdev *csi2dc_sd,
> >> + struct v4l2_subdev_frame_interval *interval)
> >> +{
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> +
> >> + if (!csi2dc->completed) {
> >> + dev_dbg((csi2dc)->dev, "subdev not registered yet\n");
> >> + return 0;
> >> + }
> >> +
> >> + return v4l2_subdev_call(csi2dc->input_sd, video, g_frame_interval,
> >> + interval);
> >> +}
> >> +
> >> +static int csi2dc_s_frame_interval(struct v4l2_subdev *csi2dc_sd,
> >> + struct v4l2_subdev_frame_interval *interval)
> >> +{
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> +
> >> + if (!csi2dc->completed) {
> >> + dev_dbg((csi2dc)->dev, "subdev not registered yet\n");
> >> + return 0;
> >> + }
> >> +
> >> + return v4l2_subdev_call(csi2dc->input_sd, video, s_frame_interval,
> >> + interval);
> >
> > If your driver is used with a MC-enabled master driver, you can drop all
> > the v4l2_subdev_call() macros apart from the ones related to s_stream
> > operation.
>
> And the set frame interval for example, will it be sent to the sensor
> automatically ?
> I noticed that such operations on the master driver were not propagated
> to the underlying subdevice. How does the master device 'know' how to
> call the input_sd ? this input_sd is not referenced anywhere in the
> master driver.

That's correct. In MC-centric drivers it's the responsibility of the user
space to configure the entire pipeline.

As your device is a CSI-2 to parallel (?) converter, it may well be part of
a complex pipeline that the master driver could not know about.

I remember there was an existing stm parallel receiver that was tightly
coupled by a CSI-2 to parallel IP block where the V4L2-centric model was
used. But virtually all devices that are not just simple sensor + receiver
with DMA are MC-centric.

>
> >
> > If not, then you can drop the HAS_DEVNODE flag from the subdev flags. But
> > I'd try to avoid this route if possible.
> >
> >> +}
> >> +
> >> +static int csi2dc_enum_frame_size(struct v4l2_subdev *csi2dc_sd,
> >> + struct v4l2_subdev_pad_config *cfg,
> >> + struct v4l2_subdev_frame_size_enum *fse)
> >> +{
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> +
> >> + if (!csi2dc->completed) {
> >> + dev_dbg((csi2dc)->dev, "subdev not registered yet\n");
> >> + return 0;
> >> + }
> >> +
> >> + return v4l2_subdev_call(csi2dc->input_sd, pad, enum_frame_size, cfg,
> >> + fse);
> >> +}
> >> +
> >> +static int csi2dc_enum_frame_interval(struct v4l2_subdev *csi2dc_sd,
> >> + struct v4l2_subdev_pad_config *cfg,
> >> + struct v4l2_subdev_frame_interval_enum *fie)
> >> +{
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> +
> >> + if (!csi2dc->completed) {
> >> + dev_dbg((csi2dc)->dev, "subdev not registered yet\n");
> >> + return 0;
> >> + }
> >> +
> >> + return v4l2_subdev_call(csi2dc->input_sd, pad, enum_frame_interval, cfg,
> >> + fie);
> >> +}
> >> +
> >> +static const struct v4l2_subdev_core_ops csi2dc_core_ops = {
> >> + .s_power = csi2dc_s_power,
> >
> > Please use runtime PM instead.
> >
> >> +};
> >> +
> >> +static const struct v4l2_subdev_pad_ops csi2dc_pad_ops = {
> >> + .enum_mbus_code = csi2dc_enum_mbus_code,
> >> + .set_fmt = csi2dc_set_fmt,
> >> + .enum_frame_size = csi2dc_enum_frame_size,
> >> + .enum_frame_interval = csi2dc_enum_frame_interval,
> >> +};
> >> +
> >> +static const struct v4l2_subdev_video_ops csi2dc_video_ops = {
> >> + .s_stream = csi2dc_s_stream,
> >> + .g_frame_interval = csi2dc_g_frame_interval,
> >> + .s_frame_interval = csi2dc_s_frame_interval,
> >> +};
> >> +
> >> +static const struct v4l2_subdev_ops csi2dc_subdev_ops = {
> >> + .core = &csi2dc_core_ops,
> >> + .pad = &csi2dc_pad_ops,
> >> + .video = &csi2dc_video_ops,
> >> +};
> >> +
> >> +static int csi2dc_async_bound(struct v4l2_async_notifier *notifier,
> >> + struct v4l2_subdev *subdev,
> >> + struct v4l2_async_subdev *asd)
> >> +{
> >> + struct csi2dc_device *csi2dc = container_of(notifier->v4l2_dev,
> >> + struct csi2dc_device, v4l2_dev);
> >> + csi2dc->input_sd = subdev;
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int csi2dc_async_complete(struct v4l2_async_notifier *notifier)
> >> +{
> >> + struct csi2dc_device *csi2dc =
> >> + container_of(notifier->v4l2_dev, struct csi2dc_device, v4l2_dev);
> >
> > Over 80 characters per line. Please check the rest of the driver, too.
> >
> >> + int ret;
> >> +
> >> + ret = v4l2_device_register_subdev_nodes(&csi2dc->v4l2_dev);
> >> + if (ret < 0) {
> >> + v4l2_err(&csi2dc->v4l2_dev, "failed to register subdev nodes\n");
> >> + return ret;
> >> + }
> >> +
> >> + csi2dc_writel(csi2dc, CSI2DC_GCFG,
> >> + (CSI2DC_GCFG_HLC(csi2dc->inter_line_delay) &
> >> + CSI2DC_GCFG_HLC_MASK) |
> >> + (csi2dc->clk_gated ? 0 : CSI2DC_GCFG_MIPIFRN));
> >> +
> >> + csi2dc_writel(csi2dc, CSI2DC_VPCOL,
> >> + CSI2DC_VPCOL_COL(0xFFF) & CSI2DC_VPCOL_COL_MASK);
> >> + csi2dc_writel(csi2dc, CSI2DC_VPROW,
> >> + CSI2DC_VPROW_ROW(0xFFF) & CSI2DC_VPROW_ROW_MASK);
> >> +
> >> + csi2dc->completed = true;
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static const struct v4l2_async_notifier_operations csi2dc_async_ops = {
> >> + .bound = csi2dc_async_bound,
> >> + .complete = csi2dc_async_complete,
> >> +};
> >> +
> >> +static void csi2dc_cleanup_notifier(struct csi2dc_device *csi2dc)
> >> +{
> >> + v4l2_async_notifier_unregister(&csi2dc->notifier);
> >> + v4l2_async_notifier_cleanup(&csi2dc->notifier);
> >> +}
> >> +
> >> +static int csi2dc_prepare_notifier(struct csi2dc_device *csi2dc,
> >> + struct device_node *input_parent)
> >> +{
> >> + int ret;
> >> +
> >> + v4l2_async_notifier_init(&csi2dc->notifier);
> >> +
> >> + csi2dc->asd = kzalloc(sizeof(*csi2dc->asd), GFP_KERNEL);
> >> + if (!csi2dc->asd)
> >> + return -ENOMEM;
> >> +
> >> + csi2dc->asd->match_type = V4L2_ASYNC_MATCH_FWNODE;
> >> + csi2dc->asd->match.fwnode = of_fwnode_handle(input_parent);
> >> +
> >> + ret = v4l2_async_notifier_add_subdev(&csi2dc->notifier, csi2dc->asd);
> >> + if (ret) {
> >> + dev_err(csi2dc->dev, "failed to add async notifier.\n");
> >> + v4l2_async_notifier_cleanup(&csi2dc->notifier);
> >> + goto csi2dc_prepare_notifier_err;
> >> + }
> >> +
> >> + csi2dc->notifier.ops = &csi2dc_async_ops;
> >> +
> >> + ret = v4l2_async_notifier_register(&csi2dc->v4l2_dev,
> >> + &csi2dc->notifier);
> >> +
> >> + if (ret) {
> >> + dev_err(csi2dc->dev, "fail to register async notifier.\n");
> >> + goto csi2dc_prepare_notifier_err;
> >> + }
> >> +
> >> +csi2dc_prepare_notifier_err:
> >> + of_node_put(input_parent);
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static int csi2dc_of_parse(struct csi2dc_device *csi2dc,
> >> + struct device_node *of_node)
> >> +{
> >> + struct device_node *input_node, *sink_node, *input_parent;
> >> + struct v4l2_fwnode_endpoint input_endpoint = { 0 }, sink_endpoint = { 0 };
> >> + int ret;
> >> +
> >> + input_node = of_graph_get_next_endpoint(of_node, NULL);
> >> +
> >> + if (!input_node) {
> >> + dev_err(csi2dc->dev, "missing port node at %s, input node is mandatory.\n",
> >> + of_node->full_name);
> >> + return -EINVAL;
> >> + }
> >> +
> >> + ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(input_node),
> >> + &input_endpoint);
> >> +
> >> + if (ret) {
> >> + dev_err(csi2dc->dev, "endpoint not defined at %s\n",
> >> + of_node->full_name);
> >> + return ret;
> >> + }
> >> +
> >> + input_parent = of_graph_get_remote_port_parent(input_node);
> >> + if (!input_parent) {
> >> + dev_err(csi2dc->dev, "could not get input node's parent node.\n");
> >> + return -EINVAL;
> >> + }
> >> +
> >> + sink_node = of_graph_get_next_endpoint(of_node, input_node);
> >> +
> >> + if (sink_node)
> >> + ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(sink_node),
> >> + &sink_endpoint);
> >> +
> >> + if (!sink_node || ret) {
> >> + dev_info(csi2dc->dev, "missing sink node at %s, data pipe available only.\n",
> >> + of_node->full_name);
> >> + } else {
> >> + csi2dc->video_pipe = true;
> >> + csi2dc->vc = sink_endpoint.base.id;
> >> +
> >> + dev_dbg(csi2dc->dev, "block %s %d.%d->%d.%d video pipe VC %d\n",
> >> + of_node->full_name, input_endpoint.base.port,
> >> + input_endpoint.base.id, sink_endpoint.base.port,
> >> + sink_endpoint.base.id, csi2dc->vc);
> >> + }
> >> +
> >> + csi2dc->clk_gated = of_property_read_bool(of_node,
> >> + "microchip,clk-gated");
> >> +
> >> + dev_dbg(csi2dc->dev, "%s clock\n",
> >> + csi2dc->clk_gated ? "Gated" : "Free running");
> >> +
> >> + ret = of_property_read_u32(of_node, "microchip,inter-line-delay",
> >> + &csi2dc->inter_line_delay);
> >> +
> >> + if (ret || csi2dc->inter_line_delay > 16 ||
> >> + csi2dc->inter_line_delay == 0) {
> >> + dev_dbg(csi2dc->dev, "assuming inter line delay = 16 clocks");
> >> + csi2dc->inter_line_delay = 16;
> >> + ret = 0;
> >> + }
> >> + /* hardware automatically adds 1 */
> >> + csi2dc->inter_line_delay--;
> >> +
> >> + /* prepare async notifier for subdevice completion */
> >> +
> >> + of_node_put(sink_node);
> >> + of_node_put(input_node);
> >> +
> >> + return csi2dc_prepare_notifier(csi2dc, input_parent);
> >> +}
> >> +
> >> +static int csi2dc_probe(struct platform_device *pdev)
> >> +{
> >> + struct device *dev = &pdev->dev;
> >> + struct csi2dc_device *csi2dc;
> >> + struct resource *res = NULL;
> >> + int ret = 0;
> >> +
> >> + csi2dc = devm_kzalloc(dev, sizeof(*csi2dc), GFP_KERNEL);
> >> + if (!csi2dc)
> >> + return -ENOMEM;
> >> +
> >> + csi2dc->dev = dev;
> >> +
> >> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >> + if (!res)
> >> + return -EINVAL;
> >> +
> >> + csi2dc->base = devm_ioremap_resource(dev, res);
> >> +
> >> + if (IS_ERR(csi2dc->base)) {
> >> + dev_err(dev, "base address not set\n");
> >> + return PTR_ERR(csi2dc->base);
> >> + }
> >> +
> >> + csi2dc->pclk = devm_clk_get(dev, "pclk");
> >> + if (IS_ERR(csi2dc->pclk)) {
> >> + ret = PTR_ERR(csi2dc->pclk);
> >> + dev_err(dev, "failed to get pclk: %d\n", ret);
> >> + return ret;
> >> + }
> >> +
> >> + ret = clk_prepare_enable(csi2dc->pclk);
> >> + if (ret) {
> >> + dev_err(dev, "failed to enable pclk: %d\n", ret);
> >> + return ret;
> >> + }
> >> +
> >> + csi2dc->scck = devm_clk_get(dev, "scck");
> >> + if (IS_ERR(csi2dc->scck)) {
> >> + ret = PTR_ERR(csi2dc->scck);
> >> + dev_err(dev, "failed to get scck: %d\n", ret);
> >> + goto csi2dc_clk_fail;
> >> + }
> >> +
> >> + ret = v4l2_device_register(dev, &csi2dc->v4l2_dev);
> >> + if (ret) {
> >> + dev_err(dev, "unable to register v4l2 device.\n");
> >> + goto csi2dc_clk_fail;
> >> + }
> >> +
> >> + v4l2_subdev_init(&csi2dc->csi2dc_sd, &csi2dc_subdev_ops);
> >> +
> >> + csi2dc->csi2dc_sd.owner = THIS_MODULE;
> >> + csi2dc->csi2dc_sd.dev = dev;
> >> + snprintf(csi2dc->csi2dc_sd.name, sizeof(csi2dc->csi2dc_sd.name),
> >> + "CSI2DC.0");
> >> +
> >> + csi2dc->csi2dc_sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> >> + csi2dc->csi2dc_sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> >> + csi2dc->pads[CSI2DC_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> >> + csi2dc->pads[CSI2DC_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> >> +
> >> + ret = media_entity_pads_init(&csi2dc->csi2dc_sd.entity, CSI2DC_PADS_NUM,
> >> + csi2dc->pads);
> >> + if (ret < 0) {
> >> + dev_err(dev, "media entity init failed\n");
> >> + goto csi2dc_probe_entity_err;
> >> + }
> >> +
> >> + v4l2_set_subdevdata(&csi2dc->csi2dc_sd, pdev);
> >> +
> >> + platform_set_drvdata(pdev, &csi2dc->csi2dc_sd);
> >> +
> >> + ret = csi2dc_of_parse(csi2dc, dev->of_node);
> >> + if (ret)
> >> + goto csi2dc_probe_entity_err;
> >> +
> >> + ret = csi2dc_formats_init(csi2dc);
> >> + if (ret)
> >> + goto csi2dc_probe_error;
> >> +
> >> + ret = v4l2_async_register_subdev(&csi2dc->csi2dc_sd);
> >> + if (ret)
> >> + goto csi2dc_probe_error;
> >> +
> >> + pr_info("Microchip CSI2DC version %x\n",
> >> + csi2dc_readl(csi2dc, CSI2DC_VERSION));
> >
> > dev_info(), please. Or just dev_dbg().
> >
> >> +
> >> + pm_runtime_set_active(dev);
> >> + pm_runtime_enable(dev);
> >> + pm_request_idle(dev);
> >> +
> >> + return 0;
> >> +
> >> +csi2dc_probe_error:
> >> + v4l2_async_unregister_subdev(&csi2dc->csi2dc_sd);
> >> + csi2dc_cleanup_notifier(csi2dc);
> >> +
> >> +csi2dc_probe_entity_err:
> >> + media_entity_cleanup(&csi2dc->csi2dc_sd.entity);
> >> + v4l2_device_unregister(&csi2dc->v4l2_dev);
> >> +csi2dc_clk_fail:
> >> + clk_disable_unprepare(csi2dc->pclk);
> >> + return ret;
> >> +}
> >> +
> >> +static int csi2dc_remove(struct platform_device *pdev)
> >> +{
> >> + struct v4l2_subdev *csi2dc_sd = platform_get_drvdata(pdev);
> >> + struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
> >> +
> >> + pm_runtime_disable(&pdev->dev);
> >> + csi2dc_cleanup_notifier(csi2dc);
> >> + media_entity_cleanup(&csi2dc->csi2dc_sd.entity);
> >> + v4l2_device_unregister(&csi2dc->v4l2_dev);
> >> + clk_disable_unprepare(csi2dc->pclk);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int __maybe_unused csi2dc_runtime_suspend(struct device *dev)
> >> +{
> >> + return 0;
> >> +}
> >> +
> >> +static int __maybe_unused csi2dc_runtime_resume(struct device *dev)
> >> +{
> >> + return 0;
> >> +}
> >> +
> >> +static const struct dev_pm_ops csi2dc_dev_pm_ops = {
> >> + SET_RUNTIME_PM_OPS(csi2dc_runtime_suspend, csi2dc_runtime_resume, NULL)
> >> +};
> >> +
> >> +static const struct of_device_id csi2dc_of_match[] = {
> >> + { .compatible = "microchip,sama7g5-csi2dc" },
> >> + { }
> >> +};
> >> +
> >> +MODULE_DEVICE_TABLE(of, csi2dc_of_match);
> >> +
> >> +static struct platform_driver csi2dc_driver = {
> >> + .probe = csi2dc_probe,
> >> + .remove = csi2dc_remove,
> >> + .driver = {
> >> + .name = "microchip-csi2dc",
> >> + .pm = &csi2dc_dev_pm_ops,
> >> + .of_match_table = of_match_ptr(csi2dc_of_match),
> >> + },
> >> +};
> >> +
> >> +module_platform_driver(csi2dc_driver);
> >> +
> >> +MODULE_AUTHOR("Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>");
> >> +MODULE_DESCRIPTION("Microchip CSI2 Demux Controller driver");
> >> +MODULE_LICENSE("GPL v2");
> >> +MODULE_SUPPORTED_DEVICE("video");
> >
> > Hmm. This line needs to be more specific. I'd just drop it.
> >
> > --
> > Kind regards,
> >
> > Sakari Ailus
> >
>

--
Regards,

Sakari Ailus