root/drivers/media/platform/synopsys/dw-mipi-csi2rx.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Synopsys DesignWare MIPI CSI-2 Receiver Driver
 *
 * Copyright (C) 2019 Rockchip Electronics Co., Ltd.
 * Copyright (C) 2025 Michael Riesch <michael.riesch@wolfvision.net>
 * Copyright (C) 2026 Collabora, Ltd.
 */

#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/property.h>
#include <linux/reset.h>

#include <media/mipi-csi2.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-mc.h>
#include <media/v4l2-subdev.h>

#define SW_CPHY_EN(x)           ((x) << 0)
#define SW_DSI_EN(x)            ((x) << 4)
#define SW_DATATYPE_FS(x)       ((x) << 8)
#define SW_DATATYPE_FE(x)       ((x) << 14)
#define SW_DATATYPE_LS(x)       ((x) << 20)
#define SW_DATATYPE_LE(x)       ((x) << 26)

#define DW_REG_EXIST            BIT(31)
#define DW_REG(x)               (DW_REG_EXIST | (x))

#define DPHY_STOPSTATE_CLK_LANE         BIT(16)

#define DPHY_TEST_CTRL0_TEST_CLR        BIT(0)

#define IPI_VCID_VC(x)                  FIELD_PREP(GENMASK(1, 0), (x))
#define IPI_VCID_VC_0_1(x)              FIELD_PREP(GENMASK(3, 2), (x))
#define IPI_VCID_VC_2                   BIT(4)

#define IPI_DATA_TYPE_DT(x)             FIELD_PREP(GENMASK(5, 0), (x))
#define IPI_DATA_TYPE_EMB_DATA_EN       BIT(8)

#define IPI_MODE_CONTROLLER             BIT(1)
#define IPI_MODE_COLOR_MODE16           BIT(8)
#define IPI_MODE_CUT_THROUGH            BIT(16)
#define IPI_MODE_ENABLE                 BIT(24)

#define IPI_MEM_FLUSH_AUTO              BIT(8)

enum dw_mipi_csi2rx_regs_index {
        DW_MIPI_CSI2RX_N_LANES,
        DW_MIPI_CSI2RX_RESETN,
        DW_MIPI_CSI2RX_PHY_STATE,
        DW_MIPI_CSI2RX_ERR1,
        DW_MIPI_CSI2RX_ERR2,
        DW_MIPI_CSI2RX_MSK1,
        DW_MIPI_CSI2RX_MSK2,
        DW_MIPI_CSI2RX_CONTROL,
        /* imx93 (v150) new register */
        DW_MIPI_CSI2RX_DPHY_RSTZ,
        DW_MIPI_CSI2RX_PHY_TST_CTRL0,
        DW_MIPI_CSI2RX_PHY_TST_CTRL1,
        DW_MIPI_CSI2RX_PHY_SHUTDOWNZ,
        DW_MIPI_CSI2RX_PHY_STOPSTATE,
        DW_MIPI_CSI2RX_IPI_DATATYPE,
        DW_MIPI_CSI2RX_IPI_MEM_FLUSH,
        DW_MIPI_CSI2RX_IPI_MODE,
        DW_MIPI_CSI2RX_IPI_SOFTRSTN,
        DW_MIPI_CSI2RX_IPI_VCID,

        DW_MIPI_CSI2RX_MAX,
};

enum {
        DW_MIPI_CSI2RX_PAD_SINK,
        DW_MIPI_CSI2RX_PAD_SRC,
        DW_MIPI_CSI2RX_PAD_MAX,
};

struct dw_mipi_csi2rx_device;

struct dw_mipi_csi2rx_drvdata {
        const u32 *regs;
        void (*dphy_assert_reset)(struct dw_mipi_csi2rx_device *csi2);
        void (*dphy_deassert_reset)(struct dw_mipi_csi2rx_device *csi2);
        void (*ipi_enable)(struct dw_mipi_csi2rx_device *csi2);
        int (*wait_for_phy_stopstate)(struct dw_mipi_csi2rx_device *csi2);
};

struct dw_mipi_csi2rx_format {
        u32 code;
        u8 depth;
        u8 csi_dt;
};

struct dw_mipi_csi2rx_device {
        struct device *dev;

        void __iomem *base_addr;
        struct clk_bulk_data *clks;
        unsigned int clks_num;
        struct phy *phy;
        struct reset_control *reset;

        const struct dw_mipi_csi2rx_format *formats;
        unsigned int formats_num;

        struct media_pad pads[DW_MIPI_CSI2RX_PAD_MAX];
        struct v4l2_async_notifier notifier;
        struct v4l2_subdev sd;

        enum v4l2_mbus_type bus_type;
        u32 lanes_num;
        u64 enabled_streams;

        const struct dw_mipi_csi2rx_drvdata *drvdata;
};

static const u32 rk3568_regs[DW_MIPI_CSI2RX_MAX] = {
        [DW_MIPI_CSI2RX_N_LANES] = DW_REG(0x4),
        [DW_MIPI_CSI2RX_RESETN] = DW_REG(0x10),
        [DW_MIPI_CSI2RX_PHY_STATE] = DW_REG(0x14),
        [DW_MIPI_CSI2RX_ERR1] = DW_REG(0x20),
        [DW_MIPI_CSI2RX_ERR2] = DW_REG(0x24),
        [DW_MIPI_CSI2RX_MSK1] = DW_REG(0x28),
        [DW_MIPI_CSI2RX_MSK2] = DW_REG(0x2c),
        [DW_MIPI_CSI2RX_CONTROL] = DW_REG(0x40),
};

static const struct dw_mipi_csi2rx_drvdata rk3568_drvdata = {
        .regs = rk3568_regs,
};

static const u32 imx93_regs[DW_MIPI_CSI2RX_MAX] = {
        [DW_MIPI_CSI2RX_N_LANES] = DW_REG(0x4),
        [DW_MIPI_CSI2RX_RESETN] = DW_REG(0x8),
        [DW_MIPI_CSI2RX_PHY_SHUTDOWNZ] = DW_REG(0x40),
        [DW_MIPI_CSI2RX_DPHY_RSTZ] = DW_REG(0x44),
        [DW_MIPI_CSI2RX_PHY_STATE] = DW_REG(0x48),
        [DW_MIPI_CSI2RX_PHY_STOPSTATE] = DW_REG(0x4c),
        [DW_MIPI_CSI2RX_PHY_TST_CTRL0] = DW_REG(0x50),
        [DW_MIPI_CSI2RX_PHY_TST_CTRL1] = DW_REG(0x54),
        [DW_MIPI_CSI2RX_IPI_MODE] = DW_REG(0x80),
        [DW_MIPI_CSI2RX_IPI_VCID] = DW_REG(0x84),
        [DW_MIPI_CSI2RX_IPI_DATATYPE] = DW_REG(0x88),
        [DW_MIPI_CSI2RX_IPI_MEM_FLUSH] = DW_REG(0x8c),
        [DW_MIPI_CSI2RX_IPI_SOFTRSTN] = DW_REG(0xa0),
};

static const u32 imx95_regs[DW_MIPI_CSI2RX_MAX] = {
        [DW_MIPI_CSI2RX_N_LANES] = DW_REG(0x4),
        [DW_MIPI_CSI2RX_RESETN] = DW_REG(0x8),
        [DW_MIPI_CSI2RX_PHY_SHUTDOWNZ] = DW_REG(0x40),
        [DW_MIPI_CSI2RX_DPHY_RSTZ] = DW_REG(0x44),
        [DW_MIPI_CSI2RX_PHY_STATE] = DW_REG(0x48),
        [DW_MIPI_CSI2RX_PHY_STOPSTATE] = DW_REG(0x4c),
        [DW_MIPI_CSI2RX_PHY_TST_CTRL0] = DW_REG(0x50),
        [DW_MIPI_CSI2RX_PHY_TST_CTRL1] = DW_REG(0x54),
};

static const struct v4l2_mbus_framefmt default_format = {
        .width = 3840,
        .height = 2160,
        .code = MEDIA_BUS_FMT_SRGGB10_1X10,
        .field = V4L2_FIELD_NONE,
        .colorspace = V4L2_COLORSPACE_RAW,
        .ycbcr_enc = V4L2_YCBCR_ENC_601,
        .quantization = V4L2_QUANTIZATION_FULL_RANGE,
        .xfer_func = V4L2_XFER_FUNC_NONE,
};

static const struct dw_mipi_csi2rx_format formats[] = {
        /* YUV formats */
        {
                .code = MEDIA_BUS_FMT_YUYV8_1X16,
                .depth = 16,
                .csi_dt = MIPI_CSI2_DT_YUV422_8B,
        },
        {
                .code = MEDIA_BUS_FMT_UYVY8_1X16,
                .depth = 16,
                .csi_dt = MIPI_CSI2_DT_YUV422_8B,
        },
        {
                .code = MEDIA_BUS_FMT_YVYU8_1X16,
                .depth = 16,
                .csi_dt = MIPI_CSI2_DT_YUV422_8B,
        },
        {
                .code = MEDIA_BUS_FMT_VYUY8_1X16,
                .depth = 16,
                .csi_dt = MIPI_CSI2_DT_YUV422_8B,
        },
        /* RGB formats */
        {
                .code = MEDIA_BUS_FMT_RGB888_1X24,
                .depth = 24,
                .csi_dt = MIPI_CSI2_DT_RGB888,
        },
        {
                .code = MEDIA_BUS_FMT_BGR888_1X24,
                .depth = 24,
                .csi_dt = MIPI_CSI2_DT_RGB888,
        },
        /* Bayer formats */
        {
                .code = MEDIA_BUS_FMT_SBGGR8_1X8,
                .depth = 8,
                .csi_dt = MIPI_CSI2_DT_RAW8,
        },
        {
                .code = MEDIA_BUS_FMT_SGBRG8_1X8,
                .depth = 8,
                .csi_dt = MIPI_CSI2_DT_RAW8,
        },
        {
                .code = MEDIA_BUS_FMT_SGRBG8_1X8,
                .depth = 8,
                .csi_dt = MIPI_CSI2_DT_RAW8,
        },
        {
                .code = MEDIA_BUS_FMT_SRGGB8_1X8,
                .depth = 8,
                .csi_dt = MIPI_CSI2_DT_RAW8,
        },
        {
                .code = MEDIA_BUS_FMT_SBGGR10_1X10,
                .depth = 10,
                .csi_dt = MIPI_CSI2_DT_RAW10,
        },
        {
                .code = MEDIA_BUS_FMT_SGBRG10_1X10,
                .depth = 10,
                .csi_dt = MIPI_CSI2_DT_RAW10,
        },
        {
                .code = MEDIA_BUS_FMT_SGRBG10_1X10,
                .depth = 10,
                .csi_dt = MIPI_CSI2_DT_RAW10,
        },
        {
                .code = MEDIA_BUS_FMT_SRGGB10_1X10,
                .depth = 10,
                .csi_dt = MIPI_CSI2_DT_RAW10,
        },
        {
                .code = MEDIA_BUS_FMT_SBGGR12_1X12,
                .depth = 12,
                .csi_dt = MIPI_CSI2_DT_RAW12,
        },
        {
                .code = MEDIA_BUS_FMT_SGBRG12_1X12,
                .depth = 12,
                .csi_dt = MIPI_CSI2_DT_RAW12,
        },
        {
                .code = MEDIA_BUS_FMT_SGRBG12_1X12,
                .depth = 12,
                .csi_dt = MIPI_CSI2_DT_RAW12,
        },
        {
                .code = MEDIA_BUS_FMT_SRGGB12_1X12,
                .depth = 12,
                .csi_dt = MIPI_CSI2_DT_RAW12,
        },
        {
                .code = MEDIA_BUS_FMT_SBGGR16_1X16,
                .depth = 16,
                .csi_dt = MIPI_CSI2_DT_RAW16,
        },
        {
                .code = MEDIA_BUS_FMT_SGBRG16_1X16,
                .depth = 16,
                .csi_dt = MIPI_CSI2_DT_RAW16,
        },
        {
                .code = MEDIA_BUS_FMT_SGRBG16_1X16,
                .depth = 16,
                .csi_dt = MIPI_CSI2_DT_RAW16,
        },
        {
                .code = MEDIA_BUS_FMT_SRGGB16_1X16,
                .depth = 16,
                .csi_dt = MIPI_CSI2_DT_RAW16,
        },
};

static inline struct dw_mipi_csi2rx_device *to_csi2(struct v4l2_subdev *sd)
{
        return container_of(sd, struct dw_mipi_csi2rx_device, sd);
}

static bool dw_mipi_csi2rx_has_reg(struct dw_mipi_csi2rx_device *csi2,
                                   enum dw_mipi_csi2rx_regs_index index)
{
        if (index < DW_MIPI_CSI2RX_MAX &&
            (csi2->drvdata->regs[index] & DW_REG_EXIST))
                return true;

        return false;
}

static void __iomem *
dw_mipi_csi2rx_get_regaddr(struct dw_mipi_csi2rx_device *csi2,
                           enum dw_mipi_csi2rx_regs_index index)
{
        u32 off = (~DW_REG_EXIST) & csi2->drvdata->regs[index];

        return csi2->base_addr + off;
}

static inline void dw_mipi_csi2rx_write(struct dw_mipi_csi2rx_device *csi2,
                                        enum dw_mipi_csi2rx_regs_index index,
                                        u32 val)
{
        if (!dw_mipi_csi2rx_has_reg(csi2, index)) {
                dev_err_once(csi2->dev,
                             "write to non-existent register index: %d\n",
                             index);
                return;
        }

        writel(val, dw_mipi_csi2rx_get_regaddr(csi2, index));
}

static inline u32 dw_mipi_csi2rx_read(struct dw_mipi_csi2rx_device *csi2,
                                      enum dw_mipi_csi2rx_regs_index index)
{
        if (!dw_mipi_csi2rx_has_reg(csi2, index)) {
                dev_err_once(csi2->dev,
                             "read non-existent register index: %d\n", index);
                /* return 0 for non-existent registers */
                return 0;
        }

        return readl(dw_mipi_csi2rx_get_regaddr(csi2, index));
}

static const struct dw_mipi_csi2rx_format *
dw_mipi_csi2rx_find_format(struct dw_mipi_csi2rx_device *csi2, u32 mbus_code)
{
        WARN_ON(csi2->formats_num == 0);

        for (unsigned int i = 0; i < csi2->formats_num; i++) {
                const struct dw_mipi_csi2rx_format *format = &formats[i];

                if (format->code == mbus_code)
                        return format;
        }

        return NULL;
}

static int dw_mipi_csi2rx_start(struct dw_mipi_csi2rx_device *csi2)
{
        struct media_pad *source_pad;
        union phy_configure_opts opts;
        u32 lanes = csi2->lanes_num;
        u32 control = 0;
        s64 link_freq;
        int ret;

        if (lanes < 1 || lanes > 4)
                return -EINVAL;

        source_pad = media_pad_remote_pad_unique(
                &csi2->pads[DW_MIPI_CSI2RX_PAD_SINK]);
        if (IS_ERR(source_pad))
                return PTR_ERR(source_pad);

        /* set mult and div to 0, thus completely rely on V4L2_CID_LINK_FREQ */
        link_freq = v4l2_get_link_freq(source_pad, 0, 0);
        if (link_freq < 0)
                return link_freq;

        switch (csi2->bus_type) {
        case V4L2_MBUS_CSI2_DPHY:
                ret = phy_mipi_dphy_get_default_config_for_hsclk(link_freq * 2,
                                                                 lanes, &opts.mipi_dphy);
                if (ret)
                        return ret;

                ret = phy_set_mode(csi2->phy, PHY_MODE_MIPI_DPHY);
                if (ret)
                        return ret;

                ret = phy_configure(csi2->phy, &opts);
                if (ret)
                        return ret;

                control |= SW_CPHY_EN(0);
                break;

        case V4L2_MBUS_CSI2_CPHY:
                /* TODO: implement CPHY configuration */
                return -EOPNOTSUPP;
        default:
                return -EINVAL;
        }

        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_RESETN, 0);

        if (csi2->drvdata->dphy_assert_reset)
                csi2->drvdata->dphy_assert_reset(csi2);

        control |= SW_DATATYPE_FS(0x00) | SW_DATATYPE_FE(0x01) |
                   SW_DATATYPE_LS(0x02) | SW_DATATYPE_LE(0x03);

        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_N_LANES, lanes - 1);

        if (dw_mipi_csi2rx_has_reg(csi2, DW_MIPI_CSI2RX_CONTROL))
                dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_CONTROL, control);

        ret = phy_power_on(csi2->phy);
        if (ret)
                return ret;

        if (csi2->drvdata->dphy_deassert_reset)
                csi2->drvdata->dphy_deassert_reset(csi2);

        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_RESETN, 1);

        if (csi2->drvdata->ipi_enable)
                csi2->drvdata->ipi_enable(csi2);

        return 0;
}

static void dw_mipi_csi2rx_stop(struct dw_mipi_csi2rx_device *csi2)
{
        phy_power_off(csi2->phy);

        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_RESETN, 0);

        if (dw_mipi_csi2rx_has_reg(csi2, DW_MIPI_CSI2RX_MSK1))
                dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_MSK1, ~0);

        if (dw_mipi_csi2rx_has_reg(csi2, DW_MIPI_CSI2RX_MSK2))
                dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_MSK2, ~0);
}

static const struct media_entity_operations dw_mipi_csi2rx_media_ops = {
        .link_validate = v4l2_subdev_link_validate,
};

static int
dw_mipi_csi2rx_enum_mbus_code(struct v4l2_subdev *sd,
                              struct v4l2_subdev_state *sd_state,
                              struct v4l2_subdev_mbus_code_enum *code)
{
        struct dw_mipi_csi2rx_device *csi2 = to_csi2(sd);

        switch (code->pad) {
        case DW_MIPI_CSI2RX_PAD_SRC:
                if (code->index)
                        return -EINVAL;

                code->code =
                        v4l2_subdev_state_get_format(sd_state,
                                                     DW_MIPI_CSI2RX_PAD_SINK)->code;

                return 0;
        case DW_MIPI_CSI2RX_PAD_SINK:
                if (code->index >= csi2->formats_num)
                        return -EINVAL;

                code->code = formats[code->index].code;
                return 0;
        default:
                return -EINVAL;
        }
}

static int dw_mipi_csi2rx_set_fmt(struct v4l2_subdev *sd,
                                  struct v4l2_subdev_state *state,
                                  struct v4l2_subdev_format *format)
{
        struct dw_mipi_csi2rx_device *csi2 = to_csi2(sd);
        const struct dw_mipi_csi2rx_format *fmt;
        struct v4l2_mbus_framefmt *sink, *src;

        /* the format on the source pad always matches the sink pad */
        if (format->pad == DW_MIPI_CSI2RX_PAD_SRC)
                return v4l2_subdev_get_fmt(sd, state, format);

        sink = v4l2_subdev_state_get_format(state, format->pad, format->stream);
        if (!sink)
                return -EINVAL;

        fmt = dw_mipi_csi2rx_find_format(csi2, format->format.code);
        if (!fmt)
                format->format = default_format;

        *sink = format->format;

        /* propagate the format to the source pad */
        src = v4l2_subdev_state_get_opposite_stream_format(state, format->pad,
                                                           format->stream);
        if (!src)
                return -EINVAL;

        *src = *sink;

        /* Store the CSIS format descriptor for active formats. */
        if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
                csi2->formats = fmt ? :
                        dw_mipi_csi2rx_find_format(csi2, default_format.code);

                if (!csi2->formats) {
                        dev_err(csi2->dev, "Failed to find valid format\n");
                        return -EINVAL;
                }
        }

        return 0;
}

static int dw_mipi_csi2rx_set_routing(struct v4l2_subdev *sd,
                                      struct v4l2_subdev_state *state,
                                      enum v4l2_subdev_format_whence which,
                                      struct v4l2_subdev_krouting *routing)
{
        int ret;

        ret = v4l2_subdev_routing_validate(sd, routing,
                                           V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
        if (ret)
                return ret;

        return v4l2_subdev_set_routing_with_fmt(sd, state, routing,
                                                &default_format);
}

static int dw_mipi_csi2rx_enable_streams(struct v4l2_subdev *sd,
                                         struct v4l2_subdev_state *state,
                                         u32 pad, u64 streams_mask)
{
        struct dw_mipi_csi2rx_device *csi2 = to_csi2(sd);
        struct v4l2_subdev *remote_sd;
        struct media_pad *sink_pad, *remote_pad;
        struct device *dev = csi2->dev;
        u64 mask;
        int ret;

        sink_pad = &sd->entity.pads[DW_MIPI_CSI2RX_PAD_SINK];
        remote_pad = media_pad_remote_pad_first(sink_pad);
        remote_sd = media_entity_to_v4l2_subdev(remote_pad->entity);

        mask = v4l2_subdev_state_xlate_streams(state, DW_MIPI_CSI2RX_PAD_SINK,
                                               DW_MIPI_CSI2RX_PAD_SRC,
                                               &streams_mask);

        if (!csi2->enabled_streams) {
                ret = pm_runtime_resume_and_get(dev);
                if (ret)
                        goto err;

                ret = dw_mipi_csi2rx_start(csi2);
                if (ret) {
                        dev_err(dev, "failed to enable CSI hardware\n");
                        goto err_pm_runtime_put;
                }
        }

        ret = v4l2_subdev_enable_streams(remote_sd, remote_pad->index, mask);
        if (ret)
                goto err_csi_stop;

        if (!csi2->enabled_streams &&
            csi2->drvdata->wait_for_phy_stopstate) {
                ret = csi2->drvdata->wait_for_phy_stopstate(csi2);
                if (ret)
                        goto err_disable_streams;
        }

        csi2->enabled_streams |= streams_mask;

        return 0;

err_disable_streams:
        v4l2_subdev_disable_streams(remote_sd, remote_pad->index, mask);
err_csi_stop:
        /* Stop CSI hardware if no streams are enabled */
        if (!csi2->enabled_streams)
                dw_mipi_csi2rx_stop(csi2);
err_pm_runtime_put:
        if (!csi2->enabled_streams)
                pm_runtime_put(dev);
err:
        return ret;
}

static int dw_mipi_csi2rx_disable_streams(struct v4l2_subdev *sd,
                                          struct v4l2_subdev_state *state,
                                          u32 pad, u64 streams_mask)
{
        struct dw_mipi_csi2rx_device *csi2 = to_csi2(sd);
        struct v4l2_subdev *remote_sd;
        struct media_pad *sink_pad, *remote_pad;
        struct device *dev = csi2->dev;
        u64 mask;
        int ret;

        sink_pad = &sd->entity.pads[DW_MIPI_CSI2RX_PAD_SINK];
        remote_pad = media_pad_remote_pad_first(sink_pad);
        remote_sd = media_entity_to_v4l2_subdev(remote_pad->entity);

        mask = v4l2_subdev_state_xlate_streams(state, DW_MIPI_CSI2RX_PAD_SINK,
                                               DW_MIPI_CSI2RX_PAD_SRC,
                                               &streams_mask);

        ret = v4l2_subdev_disable_streams(remote_sd, remote_pad->index, mask);
        if (ret)
                dev_err(dev, "failed to disable streams on remote subdev: %d\n", ret);

        csi2->enabled_streams &= ~streams_mask;

        if (!csi2->enabled_streams) {
                dw_mipi_csi2rx_stop(csi2);
                pm_runtime_put(dev);
        }

        return ret;
}

static int
dw_mipi_csi2rx_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad,
                              struct v4l2_mbus_frame_desc *fd)
{
        struct dw_mipi_csi2rx_device *csi2 = to_csi2(sd);
        struct v4l2_subdev *remote_sd;
        struct media_pad *remote_pad;

        remote_pad = media_pad_remote_pad_unique(&csi2->pads[DW_MIPI_CSI2RX_PAD_SINK]);
        if (IS_ERR(remote_pad)) {
                dev_err(csi2->dev, "can't get remote source pad\n");
                return PTR_ERR(remote_pad);
        }

        remote_sd = media_entity_to_v4l2_subdev(remote_pad->entity);

        return v4l2_subdev_call(remote_sd, pad, get_frame_desc,
                                remote_pad->index, fd);
}

static const struct v4l2_subdev_pad_ops dw_mipi_csi2rx_pad_ops = {
        .enum_mbus_code = dw_mipi_csi2rx_enum_mbus_code,
        .get_fmt = v4l2_subdev_get_fmt,
        .set_fmt = dw_mipi_csi2rx_set_fmt,
        .get_frame_desc = dw_mipi_csi2rx_get_frame_desc,
        .set_routing = dw_mipi_csi2rx_set_routing,
        .enable_streams = dw_mipi_csi2rx_enable_streams,
        .disable_streams = dw_mipi_csi2rx_disable_streams,
};

static const struct v4l2_subdev_ops dw_mipi_csi2rx_ops = {
        .pad = &dw_mipi_csi2rx_pad_ops,
};

static int dw_mipi_csi2rx_init_state(struct v4l2_subdev *sd,
                                     struct v4l2_subdev_state *state)
{
        struct v4l2_subdev_route routes[] = {
                {
                        .sink_pad = DW_MIPI_CSI2RX_PAD_SINK,
                        .sink_stream = 0,
                        .source_pad = DW_MIPI_CSI2RX_PAD_SRC,
                        .source_stream = 0,
                        .flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
                },
        };
        struct v4l2_subdev_krouting routing = {
                .len_routes = ARRAY_SIZE(routes),
                .num_routes = ARRAY_SIZE(routes),
                .routes = routes,
        };

        return v4l2_subdev_set_routing_with_fmt(sd, state, &routing,
                                                &default_format);
}

static const struct v4l2_subdev_internal_ops dw_mipi_csi2rx_internal_ops = {
        .init_state = dw_mipi_csi2rx_init_state,
};

static int dw_mipi_csi2rx_notifier_bound(struct v4l2_async_notifier *notifier,
                                         struct v4l2_subdev *sd,
                                         struct v4l2_async_connection *asd)
{
        struct dw_mipi_csi2rx_device *csi2 =
                container_of(notifier, struct dw_mipi_csi2rx_device, notifier);
        struct media_pad *sink_pad = &csi2->pads[DW_MIPI_CSI2RX_PAD_SINK];
        int ret;

        ret = v4l2_create_fwnode_links_to_pad(sd, sink_pad,
                                              MEDIA_LNK_FL_ENABLED);
        if (ret) {
                dev_err(csi2->dev, "failed to link source pad of %s\n",
                        sd->name);
                return ret;
        }

        return 0;
}

static const struct v4l2_async_notifier_operations dw_mipi_csi2rx_notifier_ops = {
        .bound = dw_mipi_csi2rx_notifier_bound,
};

static int dw_mipi_csi2rx_register_notifier(struct dw_mipi_csi2rx_device *csi2)
{
        struct v4l2_async_connection *asd;
        struct v4l2_async_notifier *ntf = &csi2->notifier;
        struct v4l2_fwnode_endpoint vep;
        struct v4l2_subdev *sd = &csi2->sd;
        struct device *dev = csi2->dev;
        int ret;

        struct fwnode_handle *ep __free(fwnode_handle) =
                fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0, 0);
        if (!ep)
                return dev_err_probe(dev, -ENODEV, "failed to get endpoint\n");

        vep.bus_type = V4L2_MBUS_UNKNOWN;
        ret = v4l2_fwnode_endpoint_parse(ep, &vep);
        if (ret)
                return dev_err_probe(dev, ret, "failed to parse endpoint\n");

        if (vep.bus_type != V4L2_MBUS_CSI2_DPHY &&
            vep.bus_type != V4L2_MBUS_CSI2_CPHY)
                return dev_err_probe(dev, -EINVAL,
                                     "invalid bus type of endpoint\n");

        csi2->bus_type = vep.bus_type;
        csi2->lanes_num = vep.bus.mipi_csi2.num_data_lanes;

        v4l2_async_subdev_nf_init(ntf, sd);
        ntf->ops = &dw_mipi_csi2rx_notifier_ops;

        asd = v4l2_async_nf_add_fwnode_remote(ntf, ep,
                                              struct v4l2_async_connection);
        if (IS_ERR(asd)) {
                ret = PTR_ERR(asd);
                goto err_nf_cleanup;
        }

        ret = v4l2_async_nf_register(ntf);
        if (ret) {
                ret = dev_err_probe(dev, ret, "failed to register notifier\n");
                goto err_nf_cleanup;
        }

        return 0;

err_nf_cleanup:
        v4l2_async_nf_cleanup(ntf);

        return ret;
}

static int dw_mipi_csi2rx_register(struct dw_mipi_csi2rx_device *csi2)
{
        struct media_pad *pads = csi2->pads;
        struct v4l2_subdev *sd = &csi2->sd;
        int ret;

        ret = dw_mipi_csi2rx_register_notifier(csi2);
        if (ret)
                goto err;

        v4l2_subdev_init(sd, &dw_mipi_csi2rx_ops);
        sd->dev = csi2->dev;
        sd->entity.ops = &dw_mipi_csi2rx_media_ops;
        sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
        sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
        sd->internal_ops = &dw_mipi_csi2rx_internal_ops;
        snprintf(sd->name, sizeof(sd->name), "dw-mipi-csi2rx %s",
                 dev_name(csi2->dev));

        pads[DW_MIPI_CSI2RX_PAD_SINK].flags = MEDIA_PAD_FL_SINK |
                                              MEDIA_PAD_FL_MUST_CONNECT;
        pads[DW_MIPI_CSI2RX_PAD_SRC].flags = MEDIA_PAD_FL_SOURCE;
        ret = media_entity_pads_init(&sd->entity, DW_MIPI_CSI2RX_PAD_MAX, pads);
        if (ret)
                goto err_notifier_unregister;

        ret = v4l2_subdev_init_finalize(sd);
        if (ret)
                goto err_entity_cleanup;

        ret = v4l2_async_register_subdev(sd);
        if (ret) {
                dev_err(sd->dev, "failed to register CSI-2 subdev\n");
                goto err_subdev_cleanup;
        }

        return 0;

err_subdev_cleanup:
        v4l2_subdev_cleanup(sd);
err_entity_cleanup:
        media_entity_cleanup(&sd->entity);
err_notifier_unregister:
        v4l2_async_nf_unregister(&csi2->notifier);
        v4l2_async_nf_cleanup(&csi2->notifier);
err:
        return ret;
}

static void dw_mipi_csi2rx_unregister(struct dw_mipi_csi2rx_device *csi2)
{
        struct v4l2_subdev *sd = &csi2->sd;

        v4l2_async_unregister_subdev(sd);
        v4l2_subdev_cleanup(sd);
        media_entity_cleanup(&sd->entity);
        v4l2_async_nf_unregister(&csi2->notifier);
        v4l2_async_nf_cleanup(&csi2->notifier);
}

static void imx93_csi2rx_dphy_assert_reset(struct dw_mipi_csi2rx_device *csi2)
{
        u32 val;

        /* Release Synopsys DPHY test codes from reset */
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_DPHY_RSTZ, 0);
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_PHY_SHUTDOWNZ, 0);

        val = dw_mipi_csi2rx_read(csi2, DW_MIPI_CSI2RX_PHY_TST_CTRL0);
        val &= ~DPHY_TEST_CTRL0_TEST_CLR;
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_PHY_TST_CTRL0, val);

        val = dw_mipi_csi2rx_read(csi2, DW_MIPI_CSI2RX_PHY_TST_CTRL0);
        /* Wait for at least 15ns */
        ndelay(15);
        val |= DPHY_TEST_CTRL0_TEST_CLR;
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_PHY_TST_CTRL0, val);
}

static void imx93_csi2rx_dphy_deassert_reset(struct dw_mipi_csi2rx_device *csi2)
{
        /* Release PHY from reset */
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_PHY_SHUTDOWNZ, 0x1);
        /*
         * ndelay() is not necessary have MMIO operation, need dummy read to
         * ensure that the write operation above reaches its target.
         */
        dw_mipi_csi2rx_read(csi2, DW_MIPI_CSI2RX_PHY_SHUTDOWNZ);
        ndelay(5);
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_DPHY_RSTZ, 0x1);

        dw_mipi_csi2rx_read(csi2, DW_MIPI_CSI2RX_DPHY_RSTZ);
        ndelay(5);
}

static void imx93_csi2rx_dphy_ipi_enable(struct dw_mipi_csi2rx_device *csi2)
{
        int dt = csi2->formats->csi_dt;
        u32 val;

        /* Do IPI soft reset */
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_IPI_SOFTRSTN, 0x0);
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_IPI_SOFTRSTN, 0x1);

        /* Select virtual channel and data type to be processed by IPI */
        val = IPI_DATA_TYPE_DT(dt);
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_IPI_DATATYPE, val);

        /* Set virtual channel 0 as default */
        val  = IPI_VCID_VC(0);
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_IPI_VCID, val);

        /*
         * Select IPI camera timing mode and allow the pixel stream
         * to be non-continuous when pixel interface FIFO is empty
         */
        val = dw_mipi_csi2rx_read(csi2, DW_MIPI_CSI2RX_IPI_MODE);
        val &= ~IPI_MODE_CONTROLLER;
        val &= ~IPI_MODE_COLOR_MODE16;
        val |= IPI_MODE_CUT_THROUGH;
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_IPI_MODE, val);

        /* Memory is automatically flushed at each Frame Start */
        val = IPI_MEM_FLUSH_AUTO;
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_IPI_MEM_FLUSH, val);

        /* Enable IPI */
        val = dw_mipi_csi2rx_read(csi2, DW_MIPI_CSI2RX_IPI_MODE);
        val |= IPI_MODE_ENABLE;
        dw_mipi_csi2rx_write(csi2, DW_MIPI_CSI2RX_IPI_MODE, val);
}

static int imx93_csi2rx_wait_for_phy_stopstate(struct dw_mipi_csi2rx_device *csi2)
{
        struct device *dev = csi2->dev;
        u32 stopstate_mask;
        u32 val;
        int ret;

        stopstate_mask = DPHY_STOPSTATE_CLK_LANE | GENMASK(csi2->lanes_num - 1, 0);

        ret = read_poll_timeout(dw_mipi_csi2rx_read, val,
                                (val & stopstate_mask) == stopstate_mask,
                                 10, 1000, true,
                                 csi2, DW_MIPI_CSI2RX_PHY_STOPSTATE);
        if (ret)
                dev_err(dev, "lanes are not in stop state: %#x, expected %#x\n",
                        val, stopstate_mask);

        return ret;
}

static const struct dw_mipi_csi2rx_drvdata imx93_drvdata = {
        .regs = imx93_regs,
        .dphy_assert_reset = imx93_csi2rx_dphy_assert_reset,
        .dphy_deassert_reset = imx93_csi2rx_dphy_deassert_reset,
        .ipi_enable = imx93_csi2rx_dphy_ipi_enable,
        .wait_for_phy_stopstate = imx93_csi2rx_wait_for_phy_stopstate,
};

static const struct dw_mipi_csi2rx_drvdata imx95_drvdata = {
        .regs = imx95_regs,
        .dphy_assert_reset = imx93_csi2rx_dphy_assert_reset,
        .dphy_deassert_reset = imx93_csi2rx_dphy_deassert_reset,
        .wait_for_phy_stopstate = imx93_csi2rx_wait_for_phy_stopstate,
};

static const struct of_device_id dw_mipi_csi2rx_of_match[] = {
        {
                .compatible = "fsl,imx93-mipi-csi2",
                .data = &imx93_drvdata,
        },
        {
                .compatible = "fsl,imx95-mipi-csi2",
                .data = &imx95_drvdata,
        },
        {
                .compatible = "rockchip,rk3568-mipi-csi2",
                .data = &rk3568_drvdata,
        },
        {}
};
MODULE_DEVICE_TABLE(of, dw_mipi_csi2rx_of_match);

static int dw_mipi_csi2rx_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct dw_mipi_csi2rx_device *csi2;
        int ret;

        csi2 = devm_kzalloc(dev, sizeof(*csi2), GFP_KERNEL);
        if (!csi2)
                return -ENOMEM;
        csi2->dev = dev;
        dev_set_drvdata(dev, csi2);

        csi2->base_addr = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(csi2->base_addr))
                return PTR_ERR(csi2->base_addr);

        csi2->drvdata = device_get_match_data(dev);
        if (!csi2->drvdata)
                return dev_err_probe(dev, -EINVAL,
                                     "failed to get driver data\n");

        ret = devm_clk_bulk_get_all(dev, &csi2->clks);
        if (ret < 0)
                return dev_err_probe(dev, -ENODEV, "failed to get clocks\n");
        csi2->clks_num = ret;

        csi2->phy = devm_phy_get(dev, NULL);
        if (IS_ERR(csi2->phy))
                return dev_err_probe(dev, PTR_ERR(csi2->phy),
                                     "failed to get MIPI CSI-2 PHY\n");

        csi2->reset = devm_reset_control_get_optional_exclusive(dev, NULL);
        if (IS_ERR(csi2->reset))
                return dev_err_probe(dev, PTR_ERR(csi2->reset),
                                     "failed to get reset\n");

        csi2->formats = formats;
        csi2->formats_num = ARRAY_SIZE(formats);

        ret = devm_pm_runtime_enable(dev);
        if (ret)
                return dev_err_probe(dev, ret, "failed to enable pm runtime\n");

        ret = phy_init(csi2->phy);
        if (ret)
                return dev_err_probe(dev, ret,
                                     "failed to initialize MIPI CSI-2 PHY\n");

        ret = dw_mipi_csi2rx_register(csi2);
        if (ret)
                goto err_phy_exit;

        return 0;

err_phy_exit:
        phy_exit(csi2->phy);

        return ret;
}

static void dw_mipi_csi2rx_remove(struct platform_device *pdev)
{
        struct dw_mipi_csi2rx_device *csi2 = platform_get_drvdata(pdev);

        dw_mipi_csi2rx_unregister(csi2);
        phy_exit(csi2->phy);
}

static int dw_mipi_csi2rx_runtime_suspend(struct device *dev)
{
        struct dw_mipi_csi2rx_device *csi2 = dev_get_drvdata(dev);

        clk_bulk_disable_unprepare(csi2->clks_num, csi2->clks);

        return 0;
}

static int dw_mipi_csi2rx_runtime_resume(struct device *dev)
{
        struct dw_mipi_csi2rx_device *csi2 = dev_get_drvdata(dev);
        int ret;

        reset_control_assert(csi2->reset);
        udelay(5);
        reset_control_deassert(csi2->reset);

        ret = clk_bulk_prepare_enable(csi2->clks_num, csi2->clks);
        if (ret) {
                dev_err(dev, "failed to enable clocks\n");
                return ret;
        }

        return 0;
}

static DEFINE_RUNTIME_DEV_PM_OPS(dw_mipi_csi2rx_pm_ops,
                                 dw_mipi_csi2rx_runtime_suspend,
                                 dw_mipi_csi2rx_runtime_resume, NULL);

static struct platform_driver dw_mipi_csi2rx_drv = {
        .driver = {
                .name = "dw-mipi-csi2rx",
                .of_match_table = dw_mipi_csi2rx_of_match,
                .pm = pm_ptr(&dw_mipi_csi2rx_pm_ops),
        },
        .probe = dw_mipi_csi2rx_probe,
        .remove = dw_mipi_csi2rx_remove,
};
module_platform_driver(dw_mipi_csi2rx_drv);

MODULE_DESCRIPTION("Synopsys DesignWare MIPI CSI-2 Receiver platform driver");
MODULE_LICENSE("GPL");