Merge tag 'trace-printf-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...

[drm/drm-misc.git] / drivers / media / platform / microchip / microchip-csi2dc.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Microchip CSI2 Demux Controller (CSI2DC) driver
 *
 * Copyright (C) 2018 Microchip Technology, Inc.
 *
 * Author: Eugen Hristev <eugen.hristev@microchip.com>
 *
 */

#include <linux/clk.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/of_graph.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/videodev2.h>

#include <media/v4l2-fwnode.h>
#include <media/v4l2-subdev.h>

/* Global configuration register */
#define CSI2DC_GCFG                     0x0

/* MIPI sensor pixel clock is free running */
#define CSI2DC_GCFG_MIPIFRN             BIT(0)
/* GPIO parallel interface selection */
#define CSI2DC_GCFG_GPIOSEL             BIT(1)
/* Output waveform inter-line minimum delay */
#define CSI2DC_GCFG_HLC(v)              ((v) << 4)
#define CSI2DC_GCFG_HLC_MASK            GENMASK(7, 4)
/* SAMA7G5 requires a HLC delay of 15 */
#define SAMA7G5_HLC                     (15)

/* 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 Interrupt Status Register */
#define CSI2DC_VPISR                    0xf4

/* 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
/* YUV data types */
#define CSI2DC_DT_YUV422_8B             0x1e

/*
 * struct csi2dc_format - CSI2DC format type struct
 * @mbus_code:          Media bus code for the format
 * @dt:                 Data type constant for this format
 */
struct csi2dc_format {
        u32                             mbus_code;
        u32                             dt;
};

static const struct csi2dc_format csi2dc_formats[] = {
        {
                .mbus_code =            MEDIA_BUS_FMT_SRGGB8_1X8,
                .dt =                   CSI2DC_DT_RAW8,
        }, {
                .mbus_code =            MEDIA_BUS_FMT_SBGGR8_1X8,
                .dt =                   CSI2DC_DT_RAW8,
        }, {
                .mbus_code =            MEDIA_BUS_FMT_SGRBG8_1X8,
                .dt =                   CSI2DC_DT_RAW8,
        }, {
                .mbus_code =            MEDIA_BUS_FMT_SGBRG8_1X8,
                .dt =                   CSI2DC_DT_RAW8,
        }, {
                .mbus_code =            MEDIA_BUS_FMT_SRGGB10_1X10,
                .dt =                   CSI2DC_DT_RAW10,
        }, {
                .mbus_code =            MEDIA_BUS_FMT_SBGGR10_1X10,
                .dt =                   CSI2DC_DT_RAW10,
        }, {
                .mbus_code =            MEDIA_BUS_FMT_SGRBG10_1X10,
                .dt =                   CSI2DC_DT_RAW10,
        }, {
                .mbus_code =            MEDIA_BUS_FMT_SGBRG10_1X10,
                .dt =                   CSI2DC_DT_RAW10,
        }, {
                .mbus_code =            MEDIA_BUS_FMT_YUYV8_2X8,
                .dt =                   CSI2DC_DT_YUV422_8B,
        },
};

enum mipi_csi_pads {
        CSI2DC_PAD_SINK                 = 0,
        CSI2DC_PAD_SOURCE               = 1,
        CSI2DC_PADS_NUM                 = 2,
};

/*
 * struct csi2dc_device - CSI2DC device driver data/config struct
 * @base:               Register map base address
 * @csi2dc_sd:          v4l2 subdevice for the csi2dc device
 *                      This is the subdevice that the csi2dc device itself
 *                      registers in v4l2 subsystem
 * @dev:                struct device for this csi2dc device
 * @pclk:               Peripheral clock reference
 *                      Input clock that clocks the hardware block internal
 *                      logic
 * @scck:               Sensor Controller clock reference
 *                      Input clock that is used to generate the pixel clock
 * @format:             Current saved format used in g/s fmt
 * @cur_fmt:            Current state format
 * @try_fmt:            Try format that is being tried
 * @pads:               Media entity pads for the csi2dc subdevice
 * @clk_gated:          Whether the clock is gated or free running
 * @video_pipe:         Whether video pipeline is configured
 * @parallel_mode:      The underlying subdevice is connected on a parallel bus
 * @vc:                 Current set virtual channel
 * @notifier:           Async notifier that is used to bound the underlying
 *                      subdevice to the csi2dc subdevice
 * @input_sd:           Reference to the underlying subdevice bound to the
 *                      csi2dc subdevice
 * @remote_pad:         Pad number of the underlying subdevice that is linked
 *                      to the csi2dc subdevice sink pad.
 */
struct csi2dc_device {
        void __iomem                    *base;
        struct v4l2_subdev              csi2dc_sd;
        struct device                   *dev;
        struct clk                      *pclk;
        struct clk                      *scck;

        struct v4l2_mbus_framefmt        format;

        const struct csi2dc_format      *cur_fmt;
        const struct csi2dc_format      *try_fmt;

        struct media_pad                pads[CSI2DC_PADS_NUM];

        bool                            clk_gated;
        bool                            video_pipe;
        bool                            parallel_mode;
        u32                             vc;

        struct v4l2_async_notifier      notifier;

        struct v4l2_subdev              *input_sd;

        u32                             remote_pad;
};

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_state *sd_state,
                                 struct v4l2_subdev_mbus_code_enum *code)
{
        if (code->index >= ARRAY_SIZE(csi2dc_formats))
                return -EINVAL;

        code->code = csi2dc_formats[code->index].mbus_code;

        return 0;
}

static int csi2dc_get_fmt(struct v4l2_subdev *csi2dc_sd,
                          struct v4l2_subdev_state *sd_state,
                          struct v4l2_subdev_format *format)
{
        struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
        struct v4l2_mbus_framefmt *v4l2_try_fmt;

        if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
                v4l2_try_fmt = v4l2_subdev_state_get_format(sd_state,
                                                            format->pad);
                format->format = *v4l2_try_fmt;

                return 0;
        }

        format->format = csi2dc->format;

        return 0;
}

static int csi2dc_set_fmt(struct v4l2_subdev *csi2dc_sd,
                          struct v4l2_subdev_state *sd_state,
                          struct v4l2_subdev_format *req_fmt)
{
        struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
        const struct csi2dc_format *fmt, *try_fmt = NULL;
        struct v4l2_mbus_framefmt *v4l2_try_fmt;
        unsigned int i;

        /*
         * Setting the source pad is disabled.
         * The same format is being propagated from the sink to source.
         */
        if (req_fmt->pad == CSI2DC_PAD_SOURCE)
                return -EINVAL;

        for (i = 0; i < ARRAY_SIZE(csi2dc_formats);  i++) {
                fmt = &csi2dc_formats[i];
                if (req_fmt->format.code == fmt->mbus_code)
                        try_fmt = fmt;
                fmt++;
        }

        /* in case we could not find the desired format, default to something */
        if (!try_fmt) {
                try_fmt = &csi2dc_formats[0];

                dev_dbg(csi2dc->dev,
                        "CSI2DC unsupported format 0x%x, defaulting to 0x%x\n",
                        req_fmt->format.code, csi2dc_formats[0].mbus_code);
        }

        req_fmt->format.code = try_fmt->mbus_code;
        req_fmt->format.colorspace = V4L2_COLORSPACE_SRGB;
        req_fmt->format.field = V4L2_FIELD_NONE;

        if (req_fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
                v4l2_try_fmt = v4l2_subdev_state_get_format(sd_state,
                                                            req_fmt->pad);
                *v4l2_try_fmt = req_fmt->format;
                /* Trying on the sink pad makes the source pad change too */
                v4l2_try_fmt = v4l2_subdev_state_get_format(sd_state,
                                                            CSI2DC_PAD_SOURCE);
                *v4l2_try_fmt = req_fmt->format;

                /* if we are just trying, we are done */
                return 0;
        }

        /* save the format for later requests */
        csi2dc->format = req_fmt->format;

        /* update config */
        csi2dc->cur_fmt = try_fmt;

        dev_dbg(csi2dc->dev, "new format set: 0x%x @%dx%d\n",
                csi2dc->format.code, csi2dc->format.width,
                csi2dc->format.height);

        return 0;
}

static int csi2dc_power(struct csi2dc_device *csi2dc, int on)
{
        int ret = 0;

        if (on) {
                ret = clk_prepare_enable(csi2dc->pclk);
                if (ret) {
                        dev_err(csi2dc->dev, "failed to enable pclk:%d\n", ret);
                        return ret;
                }

                ret = clk_prepare_enable(csi2dc->scck);
                if (ret) {
                        dev_err(csi2dc->dev, "failed to enable scck:%d\n", ret);
                        clk_disable_unprepare(csi2dc->pclk);
                        return ret;
                }

                /* if powering up, deassert reset line */
                csi2dc_writel(csi2dc, CSI2DC_GCTLR, CSI2DC_GCTLR_SWRST);
        } else {
                /* if powering down, assert reset line */
                csi2dc_writel(csi2dc, CSI2DC_GCTLR, 0);

                clk_disable_unprepare(csi2dc->scck);
                clk_disable_unprepare(csi2dc->pclk);
        }

        return ret;
}

static int csi2dc_get_mbus_config(struct csi2dc_device *csi2dc)
{
        struct v4l2_mbus_config mbus_config = { 0 };
        int ret;

        ret = v4l2_subdev_call(csi2dc->input_sd, pad, get_mbus_config,
                               csi2dc->remote_pad, &mbus_config);
        if (ret == -ENOIOCTLCMD) {
                dev_dbg(csi2dc->dev,
                        "no remote mbus configuration available\n");
                return 0;
        }

        if (ret) {
                dev_err(csi2dc->dev,
                        "failed to get remote mbus configuration\n");
                return 0;
        }

        dev_dbg(csi2dc->dev, "subdev sending on channel %d\n", csi2dc->vc);

        csi2dc->clk_gated = mbus_config.bus.parallel.flags &
                                V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;

        dev_dbg(csi2dc->dev, "mbus_config: %s clock\n",
                csi2dc->clk_gated ? "gated" : "free running");

        return 0;
}

static void csi2dc_vp_update(struct csi2dc_device *csi2dc)
{
        u32 vp, gcfg;

        if (!csi2dc->video_pipe) {
                dev_err(csi2dc->dev, "video pipeline unavailable\n");
                return;
        }

        if (csi2dc->parallel_mode) {
                /* In parallel mode, GPIO parallel interface must be selected */
                gcfg = csi2dc_readl(csi2dc, CSI2DC_GCFG);
                gcfg |= CSI2DC_GCFG_GPIOSEL;
                csi2dc_writel(csi2dc, CSI2DC_GCFG, gcfg);
                return;
        }

        /* serial video pipeline */

        csi2dc_writel(csi2dc, CSI2DC_GCFG,
                      (SAMA7G5_HLC & CSI2DC_GCFG_HLC_MASK) |
                      (csi2dc->clk_gated ? 0 : CSI2DC_GCFG_MIPIFRN));

        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 int csi2dc_s_stream(struct v4l2_subdev *csi2dc_sd, int enable)
{
        struct csi2dc_device *csi2dc = csi2dc_sd_to_csi2dc_device(csi2dc_sd);
        int ret;

        if (enable) {
                ret = pm_runtime_resume_and_get(csi2dc->dev);
                if (ret < 0)
                        return ret;

                csi2dc_get_mbus_config(csi2dc);

                csi2dc_vp_update(csi2dc);

                return v4l2_subdev_call(csi2dc->input_sd, video, s_stream,
                                        true);
        }

        dev_dbg(csi2dc->dev,
                "Last frame received: VPCOLR = %u, VPROWR= %u, VPISR = %x\n",
                csi2dc_readl(csi2dc, CSI2DC_VPCOL),
                csi2dc_readl(csi2dc, CSI2DC_VPROW),
                csi2dc_readl(csi2dc, CSI2DC_VPISR));

        /* stop streaming scenario */
        ret = v4l2_subdev_call(csi2dc->input_sd, video, s_stream, false);

        pm_runtime_put_sync(csi2dc->dev);

        return ret;
}

static int csi2dc_init_state(struct v4l2_subdev *csi2dc_sd,
                             struct v4l2_subdev_state *sd_state)
{
        struct v4l2_mbus_framefmt *v4l2_try_fmt =
                v4l2_subdev_state_get_format(sd_state, 0);

        v4l2_try_fmt->height = 480;
        v4l2_try_fmt->width = 640;
        v4l2_try_fmt->code = csi2dc_formats[0].mbus_code;
        v4l2_try_fmt->colorspace = V4L2_COLORSPACE_SRGB;
        v4l2_try_fmt->field = V4L2_FIELD_NONE;
        v4l2_try_fmt->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
        v4l2_try_fmt->quantization = V4L2_QUANTIZATION_DEFAULT;
        v4l2_try_fmt->xfer_func = V4L2_XFER_FUNC_DEFAULT;

        return 0;
}

static const struct media_entity_operations csi2dc_entity_ops = {
        .link_validate = v4l2_subdev_link_validate,
};

static const struct v4l2_subdev_pad_ops csi2dc_pad_ops = {
        .enum_mbus_code = csi2dc_enum_mbus_code,
        .set_fmt = csi2dc_set_fmt,
        .get_fmt = csi2dc_get_fmt,
};

static const struct v4l2_subdev_video_ops csi2dc_video_ops = {
        .s_stream = csi2dc_s_stream,
};

static const struct v4l2_subdev_ops csi2dc_subdev_ops = {
        .pad = &csi2dc_pad_ops,
        .video = &csi2dc_video_ops,
};

static const struct v4l2_subdev_internal_ops csi2dc_internal_ops = {
        .init_state = csi2dc_init_state,
};

static int csi2dc_async_bound(struct v4l2_async_notifier *notifier,
                              struct v4l2_subdev *subdev,
                              struct v4l2_async_connection *asd)
{
        struct csi2dc_device *csi2dc = container_of(notifier,
                                                struct csi2dc_device, notifier);
        int pad;
        int ret;

        csi2dc->input_sd = subdev;

        pad = media_entity_get_fwnode_pad(&subdev->entity, asd->match.fwnode,
                                          MEDIA_PAD_FL_SOURCE);
        if (pad < 0) {
                dev_err(csi2dc->dev, "Failed to find pad for %s\n",
                        subdev->name);
                return pad;
        }

        csi2dc->remote_pad = pad;

        ret = media_create_pad_link(&csi2dc->input_sd->entity,
                                    csi2dc->remote_pad,
                                    &csi2dc->csi2dc_sd.entity, 0,
                                    MEDIA_LNK_FL_ENABLED);
        if (ret) {
                dev_err(csi2dc->dev,
                        "Failed to create pad link: %s to %s\n",
                        csi2dc->input_sd->entity.name,
                        csi2dc->csi2dc_sd.entity.name);
                return ret;
        }

        dev_dbg(csi2dc->dev, "link with %s pad: %d\n",
                csi2dc->input_sd->name, csi2dc->remote_pad);

        return ret;
}

static const struct v4l2_async_notifier_operations csi2dc_async_ops = {
        .bound = csi2dc_async_bound,
};

static int csi2dc_prepare_notifier(struct csi2dc_device *csi2dc,
                                   struct fwnode_handle *input_fwnode)
{
        struct v4l2_async_connection *asd;
        int ret = 0;

        v4l2_async_subdev_nf_init(&csi2dc->notifier, &csi2dc->csi2dc_sd);

        asd = v4l2_async_nf_add_fwnode_remote(&csi2dc->notifier,
                                              input_fwnode,
                                              struct v4l2_async_connection);

        fwnode_handle_put(input_fwnode);

        if (IS_ERR(asd)) {
                ret = PTR_ERR(asd);
                dev_err(csi2dc->dev,
                        "failed to add async notifier for node %pOF: %d\n",
                        to_of_node(input_fwnode), ret);
                v4l2_async_nf_cleanup(&csi2dc->notifier);
                return ret;
        }

        csi2dc->notifier.ops = &csi2dc_async_ops;

        ret = v4l2_async_nf_register(&csi2dc->notifier);
        if (ret) {
                dev_err(csi2dc->dev, "fail to register async notifier: %d\n",
                        ret);
                v4l2_async_nf_cleanup(&csi2dc->notifier);
        }

        return ret;
}

static int csi2dc_of_parse(struct csi2dc_device *csi2dc,
                           struct device_node *of_node)
{
        struct fwnode_handle *input_fwnode, *output_fwnode;
        struct v4l2_fwnode_endpoint input_endpoint = { 0 },
                                    output_endpoint = { 0 };
        int ret;

        input_fwnode = fwnode_graph_get_next_endpoint(of_fwnode_handle(of_node),
                                                      NULL);
        if (!input_fwnode) {
                dev_err(csi2dc->dev,
                        "missing port node at %pOF, input node is mandatory.\n",
                        of_node);
                return -EINVAL;
        }

        ret = v4l2_fwnode_endpoint_parse(input_fwnode, &input_endpoint);
        if (ret) {
                dev_err(csi2dc->dev, "endpoint not defined at %pOF\n", of_node);
                goto csi2dc_of_parse_err;
        }

        if (input_endpoint.bus_type == V4L2_MBUS_PARALLEL ||
            input_endpoint.bus_type == V4L2_MBUS_BT656) {
                csi2dc->parallel_mode = true;
                dev_dbg(csi2dc->dev,
                        "subdevice connected on parallel interface\n");
        }

        if (input_endpoint.bus_type == V4L2_MBUS_CSI2_DPHY) {
                csi2dc->clk_gated = input_endpoint.bus.mipi_csi2.flags &
                                        V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
                dev_dbg(csi2dc->dev,
                        "subdevice connected on serial interface\n");
                dev_dbg(csi2dc->dev, "DT: %s clock\n",
                        csi2dc->clk_gated ? "gated" : "free running");
        }

        output_fwnode = fwnode_graph_get_next_endpoint
                                (of_fwnode_handle(of_node), input_fwnode);

        if (output_fwnode)
                ret = v4l2_fwnode_endpoint_parse(output_fwnode,
                                                 &output_endpoint);

        fwnode_handle_put(output_fwnode);

        if (!output_fwnode || ret) {
                dev_info(csi2dc->dev,
                         "missing output node at %pOF, data pipe available only.\n",
                         of_node);
        } else {
                if (output_endpoint.bus_type != V4L2_MBUS_PARALLEL &&
                    output_endpoint.bus_type != V4L2_MBUS_BT656) {
                        dev_err(csi2dc->dev,
                                "output port must be parallel/bt656.\n");
                        ret = -EINVAL;
                        goto csi2dc_of_parse_err;
                }

                csi2dc->video_pipe = true;

                dev_dbg(csi2dc->dev,
                        "block %pOF [%d.%d]->[%d.%d] video pipeline\n",
                        of_node, input_endpoint.base.port,
                        input_endpoint.base.id, output_endpoint.base.port,
                        output_endpoint.base.id);
        }

        /* prepare async notifier for subdevice completion */
        return csi2dc_prepare_notifier(csi2dc, input_fwnode);

csi2dc_of_parse_err:
        fwnode_handle_put(input_fwnode);
        return ret;
}

static void csi2dc_default_format(struct csi2dc_device *csi2dc)
{
        csi2dc->cur_fmt = &csi2dc_formats[0];

        csi2dc->format.height = 480;
        csi2dc->format.width = 640;
        csi2dc->format.code = csi2dc_formats[0].mbus_code;
        csi2dc->format.colorspace = V4L2_COLORSPACE_SRGB;
        csi2dc->format.field = V4L2_FIELD_NONE;
        csi2dc->format.ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
        csi2dc->format.quantization = V4L2_QUANTIZATION_DEFAULT;
        csi2dc->format.xfer_func = V4L2_XFER_FUNC_DEFAULT;
}

static int csi2dc_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct csi2dc_device *csi2dc;
        int ret = 0;
        u32 ver;

        csi2dc = devm_kzalloc(dev, sizeof(*csi2dc), GFP_KERNEL);
        if (!csi2dc)
                return -ENOMEM;

        csi2dc->dev = dev;

        csi2dc->base = devm_platform_ioremap_resource(pdev, 0);
        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;
        }

        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);
                return ret;
        }

        v4l2_subdev_init(&csi2dc->csi2dc_sd, &csi2dc_subdev_ops);
        csi2dc->csi2dc_sd.internal_ops = &csi2dc_internal_ops;

        csi2dc->csi2dc_sd.owner = THIS_MODULE;
        csi2dc->csi2dc_sd.dev = dev;
        snprintf(csi2dc->csi2dc_sd.name, sizeof(csi2dc->csi2dc_sd.name),
                 "csi2dc");

        csi2dc->csi2dc_sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
        csi2dc->csi2dc_sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
        csi2dc->csi2dc_sd.entity.ops = &csi2dc_entity_ops;

        platform_set_drvdata(pdev, csi2dc);

        ret = csi2dc_of_parse(csi2dc, dev->of_node);
        if (ret)
                goto csi2dc_probe_cleanup_entity;

        csi2dc->pads[CSI2DC_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
        if (csi2dc->video_pipe)
                csi2dc->pads[CSI2DC_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;

        ret = media_entity_pads_init(&csi2dc->csi2dc_sd.entity,
                                     csi2dc->video_pipe ? CSI2DC_PADS_NUM : 1,
                                     csi2dc->pads);
        if (ret < 0) {
                dev_err(dev, "media entity init failed\n");
                goto csi2dc_probe_cleanup_notifier;
        }

        csi2dc_default_format(csi2dc);

        /* turn power on to validate capabilities */
        ret = csi2dc_power(csi2dc, true);
        if (ret < 0)
                goto csi2dc_probe_cleanup_notifier;

        pm_runtime_set_active(dev);
        pm_runtime_enable(dev);
        ver = csi2dc_readl(csi2dc, CSI2DC_VERSION);

        /*
         * we must register the subdev after PM runtime has been requested,
         * otherwise we might bound immediately and request pm_runtime_resume
         * before runtime_enable.
         */
        ret = v4l2_async_register_subdev(&csi2dc->csi2dc_sd);
        if (ret) {
                dev_err(csi2dc->dev, "failed to register the subdevice\n");
                goto csi2dc_probe_cleanup_notifier;
        }

        dev_info(dev, "Microchip CSI2DC version %x\n", ver);

        return 0;

csi2dc_probe_cleanup_notifier:
        v4l2_async_nf_cleanup(&csi2dc->notifier);
csi2dc_probe_cleanup_entity:
        media_entity_cleanup(&csi2dc->csi2dc_sd.entity);

        return ret;
}

static void csi2dc_remove(struct platform_device *pdev)
{
        struct csi2dc_device *csi2dc = platform_get_drvdata(pdev);

        pm_runtime_disable(&pdev->dev);

        v4l2_async_unregister_subdev(&csi2dc->csi2dc_sd);
        v4l2_async_nf_unregister(&csi2dc->notifier);
        v4l2_async_nf_cleanup(&csi2dc->notifier);
        media_entity_cleanup(&csi2dc->csi2dc_sd.entity);
}

static int __maybe_unused csi2dc_runtime_suspend(struct device *dev)
{
        struct csi2dc_device *csi2dc = dev_get_drvdata(dev);

        return csi2dc_power(csi2dc, false);
}

static int __maybe_unused csi2dc_runtime_resume(struct device *dev)
{
        struct csi2dc_device *csi2dc = dev_get_drvdata(dev);

        return csi2dc_power(csi2dc, true);
}

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@microchip.com>");
MODULE_DESCRIPTION("Microchip CSI2 Demux Controller driver");
MODULE_LICENSE("GPL v2");