// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2023 Intel Corporation. All rights reserved.
 * Intel Visual Sensing Controller CSI Linux driver
 */

/*
 * To set ownership of CSI-2 link and to configure CSI-2 link, there
 * are specific commands, which are sent via MEI protocol. The send
 * command function uses "completion" as a synchronization mechanism.
 * The response for command is received via a mei callback which wakes
 * up the caller. There can be only one outstanding command at a time.
 */

#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/math64.h>
#include <linux/mei_cl_bus.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/units.h>
#include <linux/uuid.h>
#include <linux/workqueue.h>

#include <media/ipu-bridge.h>
#include <media/ipu6-pci-table.h>
#include <media/v4l2-async.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-subdev.h>

#define MEI_CSI_ENTITY_NAME "Intel IVSC CSI"

/* the 5s used here is based on experiment */
#define CSI_CMD_TIMEOUT (5 * HZ)
/* to setup CSI-2 link an extra delay needed and determined experimentally */
#define CSI_FW_READY_DELAY_MS 100
/* link frequency unit is 100kHz */
#define CSI_LINK_FREQ(x) ((u32)(div_u64(x, 100 * HZ_PER_KHZ)))

/*
 * identify the command id supported by firmware
 * IPC, as well as the privacy notification id
 * used when processing privacy event.
 */
enum csi_cmd_id {
        /* used to set csi ownership */
        CSI_SET_OWNER = 0,

        /* used to configure CSI-2 link */
        CSI_SET_CONF = 2,

        /* privacy notification id used when privacy state changes */
        CSI_PRIVACY_NOTIF = 6,
};

/* CSI-2 link ownership definition */
enum csi_link_owner {
        CSI_LINK_IVSC,
        CSI_LINK_HOST,
};

/* privacy status definition */
enum ivsc_privacy_status {
        CSI_PRIVACY_OFF,
        CSI_PRIVACY_ON,
        CSI_PRIVACY_MAX,
};

enum csi_pads {
        CSI_PAD_SINK,
        CSI_PAD_SOURCE,
        CSI_NUM_PADS
};

/* configuration of the CSI-2 link between host and IVSC */
struct csi_link_cfg {
        /* number of data lanes used on the CSI-2 link */
        u32 nr_of_lanes;

        /* frequency of the CSI-2 link */
        u32 link_freq;

        /* for future use */
        u32 rsvd[2];
} __packed;

/* CSI command structure */
struct csi_cmd {
        u32 cmd_id;
        union _cmd_param {
                u32 param;
                struct csi_link_cfg conf;
        } param;
} __packed;

/* CSI notification structure */
struct csi_notif {
        u32 cmd_id;
        int status;
        union _resp_cont {
                u32 cont;
                struct csi_link_cfg conf;
        } cont;
} __packed;

struct mei_csi {
        struct mei_cl_device *cldev;

        /* command response */
        struct csi_notif cmd_response;
        /* used to wait for command response from firmware */
        struct completion cmd_completion;
        /* protect command download */
        struct mutex lock;

        struct v4l2_subdev subdev;
        struct media_pad *remote;
        struct v4l2_async_notifier notifier;
        struct v4l2_ctrl_handler ctrl_handler;
        struct v4l2_ctrl *freq_ctrl;
        struct v4l2_ctrl *privacy_ctrl;
        /* lock for v4l2 controls */
        struct mutex ctrl_lock;
        /* start streaming or not */
        int streaming;

        struct media_pad pads[CSI_NUM_PADS];

        /* number of data lanes used on the CSI-2 link */
        u32 nr_of_lanes;
        /* frequency of the CSI-2 link */
        u64 link_freq;
};

static const struct v4l2_mbus_framefmt mei_csi_format_mbus_default = {
        .width = 1,
        .height = 1,
        .code = MEDIA_BUS_FMT_Y8_1X8,
        .field = V4L2_FIELD_NONE,
};

static inline struct mei_csi *notifier_to_csi(struct v4l2_async_notifier *n)
{
        return container_of(n, struct mei_csi, notifier);
}

static inline struct mei_csi *sd_to_csi(struct v4l2_subdev *sd)
{
        return container_of(sd, struct mei_csi, subdev);
}

/* send a command to firmware and mutex must be held by caller */
static int mei_csi_send(struct mei_csi *csi, u8 *buf, size_t len)
{
        struct csi_cmd *cmd = (struct csi_cmd *)buf;
        int ret;

        reinit_completion(&csi->cmd_completion);

        ret = mei_cldev_send(csi->cldev, buf, len);
        if (ret < 0)
                goto out;

        ret = wait_for_completion_killable_timeout(&csi->cmd_completion,
                                                   CSI_CMD_TIMEOUT);
        if (ret < 0) {
                goto out;
        } else if (!ret) {
                ret = -ETIMEDOUT;
                goto out;
        }

        /* command response status */
        ret = csi->cmd_response.status;
        if (ret == -1) {
                /* notify privacy on instead of reporting error */
                ret = 0;
                v4l2_ctrl_s_ctrl(csi->privacy_ctrl, 1);
        } else if (ret) {
                ret = -EINVAL;
                goto out;
        }

        if (csi->cmd_response.cmd_id != cmd->cmd_id)
                ret = -EINVAL;

out:
        return ret;
}

/* set CSI-2 link ownership */
static int csi_set_link_owner(struct mei_csi *csi, enum csi_link_owner owner)
{
        struct csi_cmd cmd = { 0 };
        size_t cmd_size;
        int ret;

        cmd.cmd_id = CSI_SET_OWNER;
        cmd.param.param = owner;
        cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.param);

        mutex_lock(&csi->lock);

        ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);

        mutex_unlock(&csi->lock);

        return ret;
}

/* configure CSI-2 link between host and IVSC */
static int csi_set_link_cfg(struct mei_csi *csi)
{
        struct csi_cmd cmd = { 0 };
        size_t cmd_size;
        int ret;

        cmd.cmd_id = CSI_SET_CONF;
        cmd.param.conf.nr_of_lanes = csi->nr_of_lanes;
        cmd.param.conf.link_freq = CSI_LINK_FREQ(csi->link_freq);
        cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.conf);

        mutex_lock(&csi->lock);

        ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);
        /*
         * wait configuration ready if download success. placing
         * delay under mutex is to make sure current command flow
         * completed before starting a possible new one.
         */
        if (!ret)
                msleep(CSI_FW_READY_DELAY_MS);

        mutex_unlock(&csi->lock);

        return ret;
}

/* callback for receive */
static void mei_csi_rx(struct mei_cl_device *cldev)
{
        struct mei_csi *csi = mei_cldev_get_drvdata(cldev);
        struct csi_notif notif = { 0 };
        int ret;

        ret = mei_cldev_recv(cldev, (u8 *)&notif, sizeof(notif));
        if (ret < 0) {
                dev_err(&cldev->dev, "recv error: %d\n", ret);
                return;
        }

        switch (notif.cmd_id) {
        case CSI_PRIVACY_NOTIF:
                if (notif.cont.cont < CSI_PRIVACY_MAX)
                        v4l2_ctrl_s_ctrl(csi->privacy_ctrl,
                                         notif.cont.cont == CSI_PRIVACY_ON);
                break;
        case CSI_SET_OWNER:
        case CSI_SET_CONF:
                memcpy(&csi->cmd_response, &notif, ret);

                complete(&csi->cmd_completion);
                break;
        default:
                break;
        }
}

static int mei_csi_set_stream(struct v4l2_subdev *sd, int enable)
{
        struct mei_csi *csi = sd_to_csi(sd);
        struct v4l2_subdev *remote_sd =
                media_entity_to_v4l2_subdev(csi->remote->entity);
        s64 freq;
        int ret;

        if (enable && csi->streaming == 0) {
                freq = v4l2_get_link_freq(csi->remote, 0, 0);
                if (freq < 0) {
                        dev_err(&csi->cldev->dev,
                                "error %lld, invalid link_freq\n", freq);
                        ret = freq;
                        goto err;
                }
                csi->link_freq = freq;

                /* switch CSI-2 link to host */
                ret = csi_set_link_owner(csi, CSI_LINK_HOST);
                if (ret < 0)
                        goto err;

                /* configure CSI-2 link */
                ret = csi_set_link_cfg(csi);
                if (ret < 0)
                        goto err_switch;

                ret = v4l2_subdev_call(remote_sd, video, s_stream, 1);
                if (ret)
                        goto err_switch;
        } else if (!enable && csi->streaming == 1) {
                v4l2_subdev_call(remote_sd, video, s_stream, 0);

                /* switch CSI-2 link to IVSC */
                ret = csi_set_link_owner(csi, CSI_LINK_IVSC);
                if (ret < 0)
                        dev_warn(&csi->cldev->dev,
                                 "failed to switch CSI2 link: %d\n", ret);
        }

        csi->streaming = enable;

        return 0;

err_switch:
        csi_set_link_owner(csi, CSI_LINK_IVSC);

err:
        return ret;
}

static int mei_csi_init_state(struct v4l2_subdev *sd,
                              struct v4l2_subdev_state *sd_state)
{
        struct v4l2_mbus_framefmt *mbusformat;
        unsigned int i;

        for (i = 0; i < sd->entity.num_pads; i++) {
                mbusformat = v4l2_subdev_state_get_format(sd_state, i);
                *mbusformat = mei_csi_format_mbus_default;
        }

        return 0;
}

static int mei_csi_set_fmt(struct v4l2_subdev *sd,
                           struct v4l2_subdev_state *sd_state,
                           struct v4l2_subdev_format *format)
{
        struct v4l2_mbus_framefmt *source_fmt;
        struct v4l2_mbus_framefmt *sink_fmt;

        sink_fmt = v4l2_subdev_state_get_format(sd_state, CSI_PAD_SINK);
        source_fmt = v4l2_subdev_state_get_format(sd_state, CSI_PAD_SOURCE);

        if (format->pad) {
                *source_fmt = *sink_fmt;

                return 0;
        }

        v4l_bound_align_image(&format->format.width, 1, 65536, 0,
                              &format->format.height, 1, 65536, 0, 0);

        switch (format->format.code) {
        case MEDIA_BUS_FMT_RGB444_1X12:
        case MEDIA_BUS_FMT_RGB444_2X8_PADHI_BE:
        case MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE:
        case MEDIA_BUS_FMT_RGB555_2X8_PADHI_BE:
        case MEDIA_BUS_FMT_RGB555_2X8_PADHI_LE:
        case MEDIA_BUS_FMT_RGB565_1X16:
        case MEDIA_BUS_FMT_BGR565_2X8_BE:
        case MEDIA_BUS_FMT_BGR565_2X8_LE:
        case MEDIA_BUS_FMT_RGB565_2X8_BE:
        case MEDIA_BUS_FMT_RGB565_2X8_LE:
        case MEDIA_BUS_FMT_RGB666_1X18:
        case MEDIA_BUS_FMT_RBG888_1X24:
        case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
        case MEDIA_BUS_FMT_BGR888_1X24:
        case MEDIA_BUS_FMT_GBR888_1X24:
        case MEDIA_BUS_FMT_RGB888_1X24:
        case MEDIA_BUS_FMT_RGB888_2X12_BE:
        case MEDIA_BUS_FMT_RGB888_2X12_LE:
        case MEDIA_BUS_FMT_ARGB8888_1X32:
        case MEDIA_BUS_FMT_RGB888_1X32_PADHI:
        case MEDIA_BUS_FMT_RGB101010_1X30:
        case MEDIA_BUS_FMT_RGB121212_1X36:
        case MEDIA_BUS_FMT_RGB161616_1X48:
        case MEDIA_BUS_FMT_Y8_1X8:
        case MEDIA_BUS_FMT_UV8_1X8:
        case MEDIA_BUS_FMT_UYVY8_1_5X8:
        case MEDIA_BUS_FMT_VYUY8_1_5X8:
        case MEDIA_BUS_FMT_YUYV8_1_5X8:
        case MEDIA_BUS_FMT_YVYU8_1_5X8:
        case MEDIA_BUS_FMT_UYVY8_2X8:
        case MEDIA_BUS_FMT_VYUY8_2X8:
        case MEDIA_BUS_FMT_YUYV8_2X8:
        case MEDIA_BUS_FMT_YVYU8_2X8:
        case MEDIA_BUS_FMT_Y10_1X10:
        case MEDIA_BUS_FMT_UYVY10_2X10:
        case MEDIA_BUS_FMT_VYUY10_2X10:
        case MEDIA_BUS_FMT_YUYV10_2X10:
        case MEDIA_BUS_FMT_YVYU10_2X10:
        case MEDIA_BUS_FMT_Y12_1X12:
        case MEDIA_BUS_FMT_UYVY12_2X12:
        case MEDIA_BUS_FMT_VYUY12_2X12:
        case MEDIA_BUS_FMT_YUYV12_2X12:
        case MEDIA_BUS_FMT_YVYU12_2X12:
        case MEDIA_BUS_FMT_UYVY8_1X16:
        case MEDIA_BUS_FMT_VYUY8_1X16:
        case MEDIA_BUS_FMT_YUYV8_1X16:
        case MEDIA_BUS_FMT_YVYU8_1X16:
        case MEDIA_BUS_FMT_YDYUYDYV8_1X16:
        case MEDIA_BUS_FMT_UYVY10_1X20:
        case MEDIA_BUS_FMT_VYUY10_1X20:
        case MEDIA_BUS_FMT_YUYV10_1X20:
        case MEDIA_BUS_FMT_YVYU10_1X20:
        case MEDIA_BUS_FMT_VUY8_1X24:
        case MEDIA_BUS_FMT_YUV8_1X24:
        case MEDIA_BUS_FMT_UYYVYY8_0_5X24:
        case MEDIA_BUS_FMT_UYVY12_1X24:
        case MEDIA_BUS_FMT_VYUY12_1X24:
        case MEDIA_BUS_FMT_YUYV12_1X24:
        case MEDIA_BUS_FMT_YVYU12_1X24:
        case MEDIA_BUS_FMT_YUV10_1X30:
        case MEDIA_BUS_FMT_UYYVYY10_0_5X30:
        case MEDIA_BUS_FMT_AYUV8_1X32:
        case MEDIA_BUS_FMT_UYYVYY12_0_5X36:
        case MEDIA_BUS_FMT_YUV12_1X36:
        case MEDIA_BUS_FMT_YUV16_1X48:
        case MEDIA_BUS_FMT_UYYVYY16_0_5X48:
        case MEDIA_BUS_FMT_JPEG_1X8:
        case MEDIA_BUS_FMT_AHSV8888_1X32:
        case MEDIA_BUS_FMT_SBGGR8_1X8:
        case MEDIA_BUS_FMT_SGBRG8_1X8:
        case MEDIA_BUS_FMT_SGRBG8_1X8:
        case MEDIA_BUS_FMT_SRGGB8_1X8:
        case MEDIA_BUS_FMT_SBGGR10_1X10:
        case MEDIA_BUS_FMT_SGBRG10_1X10:
        case MEDIA_BUS_FMT_SGRBG10_1X10:
        case MEDIA_BUS_FMT_SRGGB10_1X10:
        case MEDIA_BUS_FMT_SBGGR12_1X12:
        case MEDIA_BUS_FMT_SGBRG12_1X12:
        case MEDIA_BUS_FMT_SGRBG12_1X12:
        case MEDIA_BUS_FMT_SRGGB12_1X12:
        case MEDIA_BUS_FMT_SBGGR14_1X14:
        case MEDIA_BUS_FMT_SGBRG14_1X14:
        case MEDIA_BUS_FMT_SGRBG14_1X14:
        case MEDIA_BUS_FMT_SRGGB14_1X14:
        case MEDIA_BUS_FMT_SBGGR16_1X16:
        case MEDIA_BUS_FMT_SGBRG16_1X16:
        case MEDIA_BUS_FMT_SGRBG16_1X16:
        case MEDIA_BUS_FMT_SRGGB16_1X16:
                break;
        default:
                format->format.code = MEDIA_BUS_FMT_Y8_1X8;
                break;
        }

        if (format->format.field == V4L2_FIELD_ANY)
                format->format.field = V4L2_FIELD_NONE;

        *sink_fmt = format->format;
        *source_fmt = *sink_fmt;

        return 0;
}

static int mei_csi_get_mbus_config(struct v4l2_subdev *sd, unsigned int pad,
                                   struct v4l2_mbus_config *mbus_config)
{
        struct mei_csi *csi = sd_to_csi(sd);
        unsigned int i;
        s64 freq;

        mbus_config->type = V4L2_MBUS_CSI2_DPHY;
        for (i = 0; i < V4L2_MBUS_CSI2_MAX_DATA_LANES; i++)
                mbus_config->bus.mipi_csi2.data_lanes[i] = i + 1;
        mbus_config->bus.mipi_csi2.num_data_lanes = csi->nr_of_lanes;

        freq = v4l2_get_link_freq(csi->remote, 0, 0);
        if (freq < 0) {
                dev_err(&csi->cldev->dev,
                        "error %lld, invalid link_freq\n", freq);
                return -EINVAL;
        }

        csi->link_freq = freq;
        mbus_config->link_freq = freq;

        return 0;
}

static const struct v4l2_subdev_video_ops mei_csi_video_ops = {
        .s_stream = mei_csi_set_stream,
};

static const struct v4l2_subdev_pad_ops mei_csi_pad_ops = {
        .get_fmt = v4l2_subdev_get_fmt,
        .set_fmt = mei_csi_set_fmt,
        .get_mbus_config = mei_csi_get_mbus_config,
};

static const struct v4l2_subdev_ops mei_csi_subdev_ops = {
        .video = &mei_csi_video_ops,
        .pad = &mei_csi_pad_ops,
};

static const struct v4l2_subdev_internal_ops mei_csi_internal_ops = {
        .init_state = mei_csi_init_state,
};

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

static int mei_csi_notify_bound(struct v4l2_async_notifier *notifier,
                                struct v4l2_subdev *subdev,
                                struct v4l2_async_connection *asd)
{
        struct mei_csi *csi = notifier_to_csi(notifier);
        int pad;

        pad = media_entity_get_fwnode_pad(&subdev->entity, asd->match.fwnode,
                                          MEDIA_PAD_FL_SOURCE);
        if (pad < 0)
                return pad;

        csi->remote = &subdev->entity.pads[pad];

        return media_create_pad_link(&subdev->entity, pad,
                                     &csi->subdev.entity, CSI_PAD_SINK,
                                     MEDIA_LNK_FL_ENABLED |
                                     MEDIA_LNK_FL_IMMUTABLE);
}

static void mei_csi_notify_unbind(struct v4l2_async_notifier *notifier,
                                  struct v4l2_subdev *subdev,
                                  struct v4l2_async_connection *asd)
{
        struct mei_csi *csi = notifier_to_csi(notifier);

        csi->remote = NULL;
}

static const struct v4l2_async_notifier_operations mei_csi_notify_ops = {
        .bound = mei_csi_notify_bound,
        .unbind = mei_csi_notify_unbind,
};

static int mei_csi_init_controls(struct mei_csi *csi)
{
        int ret;

        mutex_init(&csi->ctrl_lock);

        ret = v4l2_ctrl_handler_init(&csi->ctrl_handler, 1);
        if (ret)
                return ret;

        csi->ctrl_handler.lock = &csi->ctrl_lock;

        csi->privacy_ctrl = v4l2_ctrl_new_std(&csi->ctrl_handler, NULL,
                                              V4L2_CID_PRIVACY, 0, 1, 1, 0);
        if (csi->privacy_ctrl)
                csi->privacy_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;

        if (csi->ctrl_handler.error)
                return csi->ctrl_handler.error;

        csi->subdev.ctrl_handler = &csi->ctrl_handler;

        return 0;
}

static int mei_csi_parse_firmware(struct mei_csi *csi)
{
        struct v4l2_fwnode_endpoint v4l2_ep = {
                .bus_type = V4L2_MBUS_CSI2_DPHY,
        };
        struct device *dev = &csi->cldev->dev;
        struct v4l2_async_connection *asd;
        struct fwnode_handle *sink_ep, *source_ep;
        int ret;

        sink_ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0, 0);
        if (!sink_ep) {
                dev_err(dev, "can't obtain sink endpoint\n");
                return -EINVAL;
        }

        v4l2_async_subdev_nf_init(&csi->notifier, &csi->subdev);
        csi->notifier.ops = &mei_csi_notify_ops;

        ret = v4l2_fwnode_endpoint_parse(sink_ep, &v4l2_ep);
        if (ret) {
                dev_err(dev, "could not parse v4l2 sink endpoint\n");
                goto out_nf_cleanup;
        }

        csi->nr_of_lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;

        source_ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 1, 0, 0);
        if (!source_ep) {
                ret = -ENOTCONN;
                dev_err(dev, "can't obtain source endpoint\n");
                goto out_nf_cleanup;
        }

        ret = v4l2_fwnode_endpoint_parse(source_ep, &v4l2_ep);
        fwnode_handle_put(source_ep);
        if (ret) {
                dev_err(dev, "could not parse v4l2 source endpoint\n");
                goto out_nf_cleanup;
        }

        if (csi->nr_of_lanes != v4l2_ep.bus.mipi_csi2.num_data_lanes) {
                ret = -EINVAL;
                dev_err(dev,
                        "the number of lanes does not match (%u vs. %u)\n",
                        csi->nr_of_lanes, v4l2_ep.bus.mipi_csi2.num_data_lanes);
                goto out_nf_cleanup;
        }

        asd = v4l2_async_nf_add_fwnode_remote(&csi->notifier, sink_ep,
                                              struct v4l2_async_connection);
        if (IS_ERR(asd)) {
                ret = PTR_ERR(asd);
                goto out_nf_cleanup;
        }

        ret = v4l2_async_nf_register(&csi->notifier);
        if (ret)
                goto out_nf_cleanup;

        fwnode_handle_put(sink_ep);

        return 0;

out_nf_cleanup:
        v4l2_async_nf_cleanup(&csi->notifier);
        fwnode_handle_put(sink_ep);

        return ret;
}

static int mei_csi_probe(struct mei_cl_device *cldev,
                         const struct mei_cl_device_id *id)
{
        struct device *dev = &cldev->dev;
        struct pci_dev *ipu;
        struct mei_csi *csi;
        unsigned int i;
        int ret;

        for (i = 0, ipu = NULL; !ipu && ipu6_pci_tbl[i].vendor; i++)
                ipu = pci_get_device(ipu6_pci_tbl[i].vendor,
                                     ipu6_pci_tbl[i].device, NULL);

        if (!ipu)
                return -ENODEV;

        ret = ipu_bridge_init(&ipu->dev, ipu_bridge_parse_ssdb);
        put_device(&ipu->dev);
        if (ret < 0)
                return ret;
        if (!dev_fwnode(dev)) {
                dev_err(dev, "mei-csi probed without device fwnode!\n");
                return -ENXIO;
        }

        csi = devm_kzalloc(dev, sizeof(struct mei_csi), GFP_KERNEL);
        if (!csi)
                return -ENOMEM;

        csi->cldev = cldev;
        mutex_init(&csi->lock);
        init_completion(&csi->cmd_completion);

        mei_cldev_set_drvdata(cldev, csi);

        ret = mei_cldev_enable(cldev);
        if (ret < 0) {
                dev_err(dev, "mei_cldev_enable failed: %d\n", ret);
                goto destroy_mutex;
        }

        ret = mei_cldev_register_rx_cb(cldev, mei_csi_rx);
        if (ret) {
                dev_err(dev, "event cb registration failed: %d\n", ret);
                goto err_disable;
        }

        ret = mei_csi_parse_firmware(csi);
        if (ret)
                goto err_disable;

        csi->subdev.dev = &cldev->dev;
        csi->subdev.state_lock = &csi->lock;
        v4l2_subdev_init(&csi->subdev, &mei_csi_subdev_ops);
        csi->subdev.internal_ops = &mei_csi_internal_ops;
        v4l2_set_subdevdata(&csi->subdev, csi);
        csi->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE |
                            V4L2_SUBDEV_FL_HAS_EVENTS;
        csi->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
        csi->subdev.entity.ops = &mei_csi_entity_ops;

        snprintf(csi->subdev.name, sizeof(csi->subdev.name),
                 MEI_CSI_ENTITY_NAME);

        ret = mei_csi_init_controls(csi);
        if (ret)
                goto err_ctrl_handler;

        csi->pads[CSI_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
        csi->pads[CSI_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
        ret = media_entity_pads_init(&csi->subdev.entity, CSI_NUM_PADS,
                                     csi->pads);
        if (ret)
                goto err_ctrl_handler;

        ret = v4l2_subdev_init_finalize(&csi->subdev);
        if (ret < 0)
                goto err_entity;

        ret = v4l2_async_register_subdev(&csi->subdev);
        if (ret < 0)
                goto err_subdev;

        pm_runtime_enable(&cldev->dev);

        return 0;

err_subdev:
        v4l2_subdev_cleanup(&csi->subdev);

err_entity:
        media_entity_cleanup(&csi->subdev.entity);

err_ctrl_handler:
        v4l2_ctrl_handler_free(&csi->ctrl_handler);
        mutex_destroy(&csi->ctrl_lock);
        v4l2_async_nf_unregister(&csi->notifier);
        v4l2_async_nf_cleanup(&csi->notifier);

err_disable:
        mei_cldev_disable(cldev);

destroy_mutex:
        mutex_destroy(&csi->lock);

        return ret;
}

static void mei_csi_remove(struct mei_cl_device *cldev)
{
        struct mei_csi *csi = mei_cldev_get_drvdata(cldev);

        v4l2_async_nf_unregister(&csi->notifier);
        v4l2_async_nf_cleanup(&csi->notifier);
        v4l2_ctrl_handler_free(&csi->ctrl_handler);
        mutex_destroy(&csi->ctrl_lock);
        v4l2_async_unregister_subdev(&csi->subdev);
        v4l2_subdev_cleanup(&csi->subdev);
        media_entity_cleanup(&csi->subdev.entity);

        pm_runtime_disable(&cldev->dev);

        mei_cldev_disable(cldev);

        mutex_destroy(&csi->lock);
}

#define MEI_CSI_UUID UUID_LE(0x92335FCF, 0x3203, 0x4472, \
                             0xAF, 0x93, 0x7b, 0x44, 0x53, 0xAC, 0x29, 0xDA)

static const struct mei_cl_device_id mei_csi_tbl[] = {
        { .uuid = MEI_CSI_UUID, .version = MEI_CL_VERSION_ANY },
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(mei, mei_csi_tbl);

static struct mei_cl_driver mei_csi_driver = {
        .id_table = mei_csi_tbl,
        .name = KBUILD_MODNAME,

        .probe = mei_csi_probe,
        .remove = mei_csi_remove,
};

module_mei_cl_driver(mei_csi_driver);

MODULE_IMPORT_NS("INTEL_IPU_BRIDGE");
MODULE_AUTHOR("Wentong Wu");
MODULE_AUTHOR("Zhifeng Wang <zhifeng.wang@intel.com>");
MODULE_DESCRIPTION("Device driver for IVSC CSI");
MODULE_LICENSE("GPL");