Re: [PATCH v2 3/4] media: misc: introduce microchip_csi2dc driver
From: Eugen.Hristev
Date: Tue Aug 25 2020 - 08:44:41 EST
On 14.08.2020 01:44, Sakari Ailus wrote:
> Hi Eugen,
>
> Thanks for the patch.
Hello Sakari,
Thanks for reviewing.
>
> On Fri, Jul 03, 2020 at 10:44:15AM +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>
>> ---
>> drivers/media/misc/Kconfig | 9 +
>> drivers/media/misc/Makefile | 1 +
>> drivers/media/misc/microchip_csi2dc.c | 705 ++++++++++++++++++++++++++
>> 3 files changed, 715 insertions(+)
>> create mode 100644 drivers/media/misc/microchip_csi2dc.c
>>
>> diff --git a/drivers/media/misc/Kconfig b/drivers/media/misc/Kconfig
>> index 206f39f86f46..86e892a41eba 100644
>> --- a/drivers/media/misc/Kconfig
>> +++ b/drivers/media/misc/Kconfig
>> @@ -8,6 +8,15 @@ menu "Miscellaneous helper chips"
>>
>> comment "Various helper chips"
>>
>> +config VIDEO_MICROCHIP_CSI2DC
>> + tristate "Microchip CSI2 Demux Controller"
>> + depends on VIDEO_V4L2
>> + 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.
>> +
>> endmenu
>>
>> endif
>> diff --git a/drivers/media/misc/Makefile b/drivers/media/misc/Makefile
>> index f66554cd5c45..86477781b7af 100644
>> --- a/drivers/media/misc/Makefile
>> +++ b/drivers/media/misc/Makefile
>> @@ -1 +1,2 @@
>> # SPDX-License-Identifier: GPL-2.0
>> +obj-$(CONFIG_VIDEO_MICROCHIP_CSI2DC) += microchip_csi2dc.o
>> diff --git a/drivers/media/misc/microchip_csi2dc.c b/drivers/media/misc/microchip_csi2dc.c
>> new file mode 100644
>> index 000000000000..494b7c137b17
>> --- /dev/null
>> +++ b/drivers/media/misc/microchip_csi2dc.c
>> @@ -0,0 +1,705 @@
>> +// 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
>
>> + {
>> + .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;
>> + 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)
>
> I'd suggest wrapping after the asterisk.
>
>> +{
>> + 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");
>
> Uh... but can you end up here?
Yes, if the subdevice has not yet registered.
The CSI2DC registers as a subdevice for the next element in pipeline
regardless of it's own subdevice.
I encountered issues when trying to register the csi2dc at a later point
than probe time (at the moment of it's own completion when the subdev is
ready).
Do you think I need to change , and have csi2dc registers itself for the
next element at a later point ?
>
>> + 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);
>
> For MC-enabled drivers (i.e. also those exposing sub-device nodes) the
> formats are set (and also enumerated) by the user and validated by the
> driver. See e.g. ipu3-cio2 driver for an example. It also includes DMA.
To fully understand, I do not need to make a subdev call ? Just validate
or invalidate the try format ?
>
>> +}
>> +
>> +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);
>> + 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)
>
> Please use runtime PM instead.
And in this case, s_power on/off will be unused?
The runtime PM will power on the pipeline when capture is required or it
will have it powered on more than that ?
Currently in my experiments when stopping the streaming, s_power off is
also called afterwards, and the CSI2DC can be reset, as the MIPI lanes
must reach a stop state to reinitialize capture later.
>
>> +{
>> + 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);
>> +
>> + 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);
>> +}
>> +
>> +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 struct v4l2_subdev_core_ops csi2dc_core_ops = {
>> + .s_power = csi2dc_s_power,
>> +};
>> +
>> +static 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 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 struct v4l2_subdev_ops csi2dc_subdev_ops = {
>> + .core = &csi2dc_core_ops,
>> + .pad = &csi2dc_pad_ops,
>> + .video = &csi2dc_video_ops,
>> +};
>
> const. Applies to all above.
>
>> +
>> +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,
>
> It'd be cleaner to wrap after "=". Or align the lines below after "(".
>
>> + struct csi2dc_device, v4l2_dev);
>> + 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, sink_endpoint;
>> + int ret;
>> +
>> + memset(&input_endpoint, 0, sizeof(input_endpoint));
>> + memset(&sink_endpoint, 0, sizeof(sink_endpoint));
>
> Could you assign a field to 0 in the declaration instead?
>
> You should also set the bus type as I believe the driver supports a single
> one at both endpoints.
I thought about that, but on the input pad, what bus type I can use ?
Synopsys IDI is not available in kernel.
>
> You could also use the fwnode property API instead so you could avoid
> of_fwnode_handle() --- up to you.
>
>> +
>> + 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);
>
> You'll need to obtain the endpoints by port here (and above, too).
I obtain them in the order in the device tree, one by one. You suggest
to use a different API such that they are obtained by port number ?
>
>> +
>> + 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"));
>
> Extra parentheses.
>
>> +
>> + ret = of_property_read_u32(of_node, "microchip,inter-line-delay",
>> + &csi2dc->inter_line_delay);
>> +
>> + if (ret || csi2dc->inter_line_delay > 16) {
>> + 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--;
>
> What happens if 0 was read from DT?
>
>> +
>> + /* prepare async notifier for subdevice completion */
>> +
>> + if (sink_node)
>> + of_node_put(sink_node);
>
> of_node_put() is NULL-safe.
>
>> + 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;
>> +
>
> No need for a newline.
>
>> + csi2dc->csi2dc_sd.dev = dev;
>> + snprintf(csi2dc->csi2dc_sd.name, sizeof(csi2dc->csi2dc_sd.name),
>> + "%s.%d", "CSI2DC", 0);
>
> The number is always zero.
>
>> +
>> + 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) { // ret = -EPROBE_DEFER;
>
> Oops.
>
>> + goto csi2dc_probe_error;
>> + }
>> +
>> + pm_runtime_set_active(dev);
>> + pm_runtime_enable(dev);
>> + pm_request_idle(dev);
>> +
>> + pr_info("Microchip CSI2DC version %x\n",
>> + csi2dc_readl(csi2dc, CSI2DC_VERSION));
>
> What happens if the device was powered down already?
I am moving the info line before pm_request_idle, if this was what you
had in mind.
I am sending a v3 of the patch, with some of the comments addressed.
Some others I do not fully understand yet how to change. Hopefully your
replies will help me find the way.
Thanks again,
Eugen
>
>> +
>> + 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");
>
> --
> Kind regards,
>
> Sakari Ailus
>