Re: [PATCH v2 3/4] media: misc: introduce microchip_csi2dc driver
From: Sakari Ailus
Date: Thu Aug 13 2020 - 18:45:11 EST
Hi Eugen,
Thanks for the patch.
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?
> + 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.
> +}
> +
> +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.
> +{
> + 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.
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).
> +
> + 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?
> +
> + 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