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

From: Eugen.Hristev
Date: Mon Sep 28 2020 - 08:32:42 EST


On 07.09.2020 12:16, Eugen Hristev - M18282 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 ?
>

Gentle ping

Thanks

>>
>> 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 ?
>
>
>>
>>> + {
>>> + .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 ?
>>
>>> + 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.
>
>>
>> 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
>>
>