// SPDX-License-Identifier: GPL-2.0-only
/*
 * V4L2 fwnode binding parsing library
 *
 * The origins of the V4L2 fwnode library are in V4L2 OF library that
 * formerly was located in v4l2-of.c.
 *
 * Copyright (c) 2016 Intel Corporation.
 * Author: Sakari Ailus <sakari.ailus@linux.intel.com>
 *
 * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
 * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
 *
 * Copyright (C) 2012 Renesas Electronics Corp.
 * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
 */
#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/types.h>

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

#include "v4l2-subdev-priv.h"

static const struct v4l2_fwnode_bus_conv {
        enum v4l2_fwnode_bus_type fwnode_bus_type;
        enum v4l2_mbus_type mbus_type;
        const char *name;
} buses[] = {
        {
                V4L2_FWNODE_BUS_TYPE_GUESS,
                V4L2_MBUS_UNKNOWN,
                "not specified",
        }, {
                V4L2_FWNODE_BUS_TYPE_CSI2_CPHY,
                V4L2_MBUS_CSI2_CPHY,
                "MIPI CSI-2 C-PHY",
        }, {
                V4L2_FWNODE_BUS_TYPE_CSI1,
                V4L2_MBUS_CSI1,
                "MIPI CSI-1",
        }, {
                V4L2_FWNODE_BUS_TYPE_CCP2,
                V4L2_MBUS_CCP2,
                "compact camera port 2",
        }, {
                V4L2_FWNODE_BUS_TYPE_CSI2_DPHY,
                V4L2_MBUS_CSI2_DPHY,
                "MIPI CSI-2 D-PHY",
        }, {
                V4L2_FWNODE_BUS_TYPE_PARALLEL,
                V4L2_MBUS_PARALLEL,
                "parallel",
        }, {
                V4L2_FWNODE_BUS_TYPE_BT656,
                V4L2_MBUS_BT656,
                "Bt.656",
        }, {
                V4L2_FWNODE_BUS_TYPE_DPI,
                V4L2_MBUS_DPI,
                "DPI",
        }
};

static const struct v4l2_fwnode_bus_conv *
get_v4l2_fwnode_bus_conv_by_fwnode_bus(enum v4l2_fwnode_bus_type type)
{
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(buses); i++)
                if (buses[i].fwnode_bus_type == type)
                        return &buses[i];

        return NULL;
}

static enum v4l2_mbus_type
v4l2_fwnode_bus_type_to_mbus(enum v4l2_fwnode_bus_type type)
{
        const struct v4l2_fwnode_bus_conv *conv =
                get_v4l2_fwnode_bus_conv_by_fwnode_bus(type);

        return conv ? conv->mbus_type : V4L2_MBUS_INVALID;
}

static const char *
v4l2_fwnode_bus_type_to_string(enum v4l2_fwnode_bus_type type)
{
        const struct v4l2_fwnode_bus_conv *conv =
                get_v4l2_fwnode_bus_conv_by_fwnode_bus(type);

        return conv ? conv->name : "not found";
}

static const struct v4l2_fwnode_bus_conv *
get_v4l2_fwnode_bus_conv_by_mbus(enum v4l2_mbus_type type)
{
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(buses); i++)
                if (buses[i].mbus_type == type)
                        return &buses[i];

        return NULL;
}

static const char *
v4l2_fwnode_mbus_type_to_string(enum v4l2_mbus_type type)
{
        const struct v4l2_fwnode_bus_conv *conv =
                get_v4l2_fwnode_bus_conv_by_mbus(type);

        return conv ? conv->name : "not found";
}

static int v4l2_fwnode_endpoint_parse_csi2_bus(struct fwnode_handle *fwnode,
                                               struct v4l2_fwnode_endpoint *vep,
                                               enum v4l2_mbus_type bus_type)
{
        struct v4l2_mbus_config_mipi_csi2 *bus = &vep->bus.mipi_csi2;
        bool have_clk_lane = false, have_data_lanes = false,
                have_lane_polarities = false, have_line_orders = false;
        unsigned int flags = 0, lanes_used = 0;
        u32 array[1 + V4L2_MBUS_CSI2_MAX_DATA_LANES];
        u32 clock_lane = 0;
        unsigned int num_data_lanes = 0;
        bool use_default_lane_mapping = false;
        unsigned int i;
        u32 v;
        int rval;

        if (bus_type == V4L2_MBUS_CSI2_DPHY ||
            bus_type == V4L2_MBUS_CSI2_CPHY) {
                use_default_lane_mapping = true;

                num_data_lanes = min_t(u32, bus->num_data_lanes,
                                       V4L2_MBUS_CSI2_MAX_DATA_LANES);

                clock_lane = bus->clock_lane;
                if (clock_lane)
                        use_default_lane_mapping = false;

                for (i = 0; i < num_data_lanes; i++) {
                        array[i] = bus->data_lanes[i];
                        if (array[i])
                                use_default_lane_mapping = false;
                }

                if (use_default_lane_mapping)
                        pr_debug("no lane mapping given, using defaults\n");
        }

        rval = fwnode_property_count_u32(fwnode, "data-lanes");
        if (rval > 0) {
                num_data_lanes =
                        min_t(int, V4L2_MBUS_CSI2_MAX_DATA_LANES, rval);

                fwnode_property_read_u32_array(fwnode, "data-lanes", array,
                                               num_data_lanes);

                have_data_lanes = true;
                if (use_default_lane_mapping) {
                        pr_debug("data-lanes property exists; disabling default mapping\n");
                        use_default_lane_mapping = false;
                }
        }

        for (i = 0; i < num_data_lanes; i++) {
                if (lanes_used & BIT(array[i])) {
                        if (have_data_lanes || !use_default_lane_mapping)
                                pr_warn("duplicated lane %u in data-lanes, using defaults\n",
                                        array[i]);
                        use_default_lane_mapping = true;
                }
                lanes_used |= BIT(array[i]);

                if (have_data_lanes)
                        pr_debug("lane %u position %u\n", i, array[i]);
        }

        rval = fwnode_property_count_u32(fwnode, "lane-polarities");
        if (rval > 0) {
                if (rval != 1 + num_data_lanes /* clock+data */) {
                        pr_warn("invalid number of lane-polarities entries (need %u, got %u)\n",
                                1 + num_data_lanes, rval);
                        return -EINVAL;
                }

                have_lane_polarities = true;
        }

        rval = fwnode_property_count_u32(fwnode, "line-orders");
        if (rval > 0) {
                if (rval != num_data_lanes) {
                        pr_warn("invalid number of line-orders entries (need %u, got %u)\n",
                                num_data_lanes, rval);
                        return -EINVAL;
                }

                have_line_orders = true;
        }

        if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) {
                clock_lane = v;
                pr_debug("clock lane position %u\n", v);
                have_clk_lane = true;
        }

        if (have_clk_lane && lanes_used & BIT(clock_lane) &&
            !use_default_lane_mapping) {
                pr_warn("duplicated lane %u in clock-lanes, using defaults\n",
                        v);
                use_default_lane_mapping = true;
        }

        if (fwnode_property_present(fwnode, "clock-noncontinuous")) {
                flags |= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
                pr_debug("non-continuous clock\n");
        }

        if (bus_type == V4L2_MBUS_CSI2_DPHY ||
            bus_type == V4L2_MBUS_CSI2_CPHY ||
            lanes_used || have_clk_lane || flags) {
                /* Only D-PHY has a clock lane. */
                unsigned int dfl_data_lane_index =
                        bus_type == V4L2_MBUS_CSI2_DPHY;

                bus->flags = flags;
                if (bus_type == V4L2_MBUS_UNKNOWN)
                        vep->bus_type = V4L2_MBUS_CSI2_DPHY;
                bus->num_data_lanes = num_data_lanes;

                if (use_default_lane_mapping) {
                        bus->clock_lane = 0;
                        for (i = 0; i < num_data_lanes; i++)
                                bus->data_lanes[i] = dfl_data_lane_index + i;
                } else {
                        bus->clock_lane = clock_lane;
                        for (i = 0; i < num_data_lanes; i++)
                                bus->data_lanes[i] = array[i];
                }

                if (have_lane_polarities) {
                        fwnode_property_read_u32_array(fwnode,
                                                       "lane-polarities", array,
                                                       1 + num_data_lanes);

                        for (i = 0; i < 1 + num_data_lanes; i++) {
                                bus->lane_polarities[i] = array[i];
                                pr_debug("lane %u polarity %sinverted",
                                         i, array[i] ? "" : "not ");
                        }
                } else {
                        pr_debug("no lane polarities defined, assuming not inverted\n");
                }

                if (have_line_orders) {
                        fwnode_property_read_u32_array(fwnode,
                                                       "line-orders", array,
                                                       num_data_lanes);

                        for (i = 0; i < num_data_lanes; i++) {
                                static const char * const orders[] = {
                                        "ABC", "ACB", "BAC", "BCA", "CAB", "CBA"
                                };

                                if (array[i] >= ARRAY_SIZE(orders)) {
                                        pr_warn("lane %u invalid line-order assuming ABC (got %u)\n",
                                                i, array[i]);
                                        bus->line_orders[i] =
                                                V4L2_MBUS_CSI2_CPHY_LINE_ORDER_ABC;
                                        continue;
                                }

                                bus->line_orders[i] = array[i];
                                pr_debug("lane %u line order %s", i,
                                         orders[array[i]]);
                        }
                } else {
                        for (i = 0; i < num_data_lanes; i++)
                                bus->line_orders[i] =
                                        V4L2_MBUS_CSI2_CPHY_LINE_ORDER_ABC;

                        pr_debug("no line orders defined, assuming ABC\n");
                }
        }

        return 0;
}

#define PARALLEL_MBUS_FLAGS (V4L2_MBUS_HSYNC_ACTIVE_HIGH |      \
                             V4L2_MBUS_HSYNC_ACTIVE_LOW |       \
                             V4L2_MBUS_VSYNC_ACTIVE_HIGH |      \
                             V4L2_MBUS_VSYNC_ACTIVE_LOW |       \
                             V4L2_MBUS_FIELD_EVEN_HIGH |        \
                             V4L2_MBUS_FIELD_EVEN_LOW)

static void
v4l2_fwnode_endpoint_parse_parallel_bus(struct fwnode_handle *fwnode,
                                        struct v4l2_fwnode_endpoint *vep,
                                        enum v4l2_mbus_type bus_type)
{
        struct v4l2_mbus_config_parallel *bus = &vep->bus.parallel;
        unsigned int flags = 0;
        u32 v;

        if (bus_type == V4L2_MBUS_PARALLEL || bus_type == V4L2_MBUS_BT656)
                flags = bus->flags;

        if (!fwnode_property_read_u32(fwnode, "hsync-active", &v)) {
                flags &= ~(V4L2_MBUS_HSYNC_ACTIVE_HIGH |
                           V4L2_MBUS_HSYNC_ACTIVE_LOW);
                flags |= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH :
                        V4L2_MBUS_HSYNC_ACTIVE_LOW;
                pr_debug("hsync-active %s\n", v ? "high" : "low");
        }

        if (!fwnode_property_read_u32(fwnode, "vsync-active", &v)) {
                flags &= ~(V4L2_MBUS_VSYNC_ACTIVE_HIGH |
                           V4L2_MBUS_VSYNC_ACTIVE_LOW);
                flags |= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH :
                        V4L2_MBUS_VSYNC_ACTIVE_LOW;
                pr_debug("vsync-active %s\n", v ? "high" : "low");
        }

        if (!fwnode_property_read_u32(fwnode, "field-even-active", &v)) {
                flags &= ~(V4L2_MBUS_FIELD_EVEN_HIGH |
                           V4L2_MBUS_FIELD_EVEN_LOW);
                flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH :
                        V4L2_MBUS_FIELD_EVEN_LOW;
                pr_debug("field-even-active %s\n", v ? "high" : "low");
        }

        if (!fwnode_property_read_u32(fwnode, "pclk-sample", &v)) {
                flags &= ~(V4L2_MBUS_PCLK_SAMPLE_RISING |
                           V4L2_MBUS_PCLK_SAMPLE_FALLING |
                           V4L2_MBUS_PCLK_SAMPLE_DUALEDGE);
                switch (v) {
                case 0:
                        flags |= V4L2_MBUS_PCLK_SAMPLE_FALLING;
                        pr_debug("pclk-sample low\n");
                        break;
                case 1:
                        flags |= V4L2_MBUS_PCLK_SAMPLE_RISING;
                        pr_debug("pclk-sample high\n");
                        break;
                case 2:
                        flags |= V4L2_MBUS_PCLK_SAMPLE_DUALEDGE;
                        pr_debug("pclk-sample dual edge\n");
                        break;
                default:
                        pr_warn("invalid argument for pclk-sample");
                        break;
                }
        }

        if (!fwnode_property_read_u32(fwnode, "data-active", &v)) {
                flags &= ~(V4L2_MBUS_DATA_ACTIVE_HIGH |
                           V4L2_MBUS_DATA_ACTIVE_LOW);
                flags |= v ? V4L2_MBUS_DATA_ACTIVE_HIGH :
                        V4L2_MBUS_DATA_ACTIVE_LOW;
                pr_debug("data-active %s\n", v ? "high" : "low");
        }

        if (fwnode_property_present(fwnode, "slave-mode")) {
                pr_debug("slave mode\n");
                flags &= ~V4L2_MBUS_MASTER;
                flags |= V4L2_MBUS_SLAVE;
        } else {
                flags &= ~V4L2_MBUS_SLAVE;
                flags |= V4L2_MBUS_MASTER;
        }

        if (!fwnode_property_read_u32(fwnode, "bus-width", &v)) {
                bus->bus_width = v;
                pr_debug("bus-width %u\n", v);
        }

        if (!fwnode_property_read_u32(fwnode, "data-shift", &v)) {
                bus->data_shift = v;
                pr_debug("data-shift %u\n", v);
        }

        if (!fwnode_property_read_u32(fwnode, "sync-on-green-active", &v)) {
                flags &= ~(V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH |
                           V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW);
                flags |= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH :
                        V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW;
                pr_debug("sync-on-green-active %s\n", v ? "high" : "low");
        }

        if (!fwnode_property_read_u32(fwnode, "data-enable-active", &v)) {
                flags &= ~(V4L2_MBUS_DATA_ENABLE_HIGH |
                           V4L2_MBUS_DATA_ENABLE_LOW);
                flags |= v ? V4L2_MBUS_DATA_ENABLE_HIGH :
                        V4L2_MBUS_DATA_ENABLE_LOW;
                pr_debug("data-enable-active %s\n", v ? "high" : "low");
        }

        switch (bus_type) {
        default:
                bus->flags = flags;
                if (flags & PARALLEL_MBUS_FLAGS)
                        vep->bus_type = V4L2_MBUS_PARALLEL;
                else
                        vep->bus_type = V4L2_MBUS_BT656;
                break;
        case V4L2_MBUS_PARALLEL:
                vep->bus_type = V4L2_MBUS_PARALLEL;
                bus->flags = flags;
                break;
        case V4L2_MBUS_BT656:
                vep->bus_type = V4L2_MBUS_BT656;
                bus->flags = flags & ~PARALLEL_MBUS_FLAGS;
                break;
        }
}

static void
v4l2_fwnode_endpoint_parse_csi1_bus(struct fwnode_handle *fwnode,
                                    struct v4l2_fwnode_endpoint *vep,
                                    enum v4l2_mbus_type bus_type)
{
        struct v4l2_mbus_config_mipi_csi1 *bus = &vep->bus.mipi_csi1;
        u32 v;

        if (!fwnode_property_read_u32(fwnode, "clock-inv", &v)) {
                bus->clock_inv = v;
                pr_debug("clock-inv %u\n", v);
        }

        if (!fwnode_property_read_u32(fwnode, "strobe", &v)) {
                bus->strobe = v;
                pr_debug("strobe %u\n", v);
        }

        if (!fwnode_property_read_u32(fwnode, "data-lanes", &v)) {
                bus->data_lane = v;
                pr_debug("data-lanes %u\n", v);
        }

        if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) {
                bus->clock_lane = v;
                pr_debug("clock-lanes %u\n", v);
        }

        if (bus_type == V4L2_MBUS_CCP2)
                vep->bus_type = V4L2_MBUS_CCP2;
        else
                vep->bus_type = V4L2_MBUS_CSI1;
}

static int __v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
                                        struct v4l2_fwnode_endpoint *vep)
{
        u32 bus_type = V4L2_FWNODE_BUS_TYPE_GUESS;
        enum v4l2_mbus_type mbus_type;
        int rval;

        if (!fwnode)
                return -EINVAL;

        pr_debug("===== begin parsing endpoint %pfw\n", fwnode);

        fwnode_property_read_u32(fwnode, "bus-type", &bus_type);
        pr_debug("fwnode video bus type %s (%u), mbus type %s (%u)\n",
                 v4l2_fwnode_bus_type_to_string(bus_type), bus_type,
                 v4l2_fwnode_mbus_type_to_string(vep->bus_type),
                 vep->bus_type);
        mbus_type = v4l2_fwnode_bus_type_to_mbus(bus_type);
        if (mbus_type == V4L2_MBUS_INVALID) {
                pr_debug("unsupported bus type %u\n", bus_type);
                return -EINVAL;
        }

        if (vep->bus_type != V4L2_MBUS_UNKNOWN) {
                if (mbus_type != V4L2_MBUS_UNKNOWN &&
                    vep->bus_type != mbus_type) {
                        pr_debug("expecting bus type %s\n",
                                 v4l2_fwnode_mbus_type_to_string(vep->bus_type));
                        return -ENXIO;
                }
        } else {
                vep->bus_type = mbus_type;
        }

        switch (vep->bus_type) {
        case V4L2_MBUS_UNKNOWN:
                rval = v4l2_fwnode_endpoint_parse_csi2_bus(fwnode, vep,
                                                           V4L2_MBUS_UNKNOWN);
                if (rval)
                        return rval;

                if (vep->bus_type == V4L2_MBUS_UNKNOWN)
                        v4l2_fwnode_endpoint_parse_parallel_bus(fwnode, vep,
                                                                V4L2_MBUS_UNKNOWN);

                pr_debug("assuming media bus type %s (%u)\n",
                         v4l2_fwnode_mbus_type_to_string(vep->bus_type),
                         vep->bus_type);

                break;
        case V4L2_MBUS_CCP2:
        case V4L2_MBUS_CSI1:
                v4l2_fwnode_endpoint_parse_csi1_bus(fwnode, vep, vep->bus_type);

                break;
        case V4L2_MBUS_CSI2_DPHY:
        case V4L2_MBUS_CSI2_CPHY:
                rval = v4l2_fwnode_endpoint_parse_csi2_bus(fwnode, vep,
                                                           vep->bus_type);
                if (rval)
                        return rval;

                break;
        case V4L2_MBUS_PARALLEL:
        case V4L2_MBUS_BT656:
                v4l2_fwnode_endpoint_parse_parallel_bus(fwnode, vep,
                                                        vep->bus_type);

                break;
        default:
                pr_warn("unsupported bus type %u\n", mbus_type);
                return -EINVAL;
        }

        fwnode_graph_parse_endpoint(fwnode, &vep->base);

        return 0;
}

int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
                               struct v4l2_fwnode_endpoint *vep)
{
        int ret;

        ret = __v4l2_fwnode_endpoint_parse(fwnode, vep);

        pr_debug("===== end parsing endpoint %pfw\n", fwnode);

        return ret;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_parse);

void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep)
{
        if (IS_ERR_OR_NULL(vep))
                return;

        kfree(vep->link_frequencies);
        vep->link_frequencies = NULL;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_free);

int v4l2_fwnode_endpoint_alloc_parse(struct fwnode_handle *fwnode,
                                     struct v4l2_fwnode_endpoint *vep)
{
        int rval;

        rval = __v4l2_fwnode_endpoint_parse(fwnode, vep);
        if (rval < 0)
                return rval;

        rval = fwnode_property_count_u64(fwnode, "link-frequencies");
        if (rval > 0) {
                unsigned int i;

                vep->link_frequencies =
                        kmalloc_array(rval, sizeof(*vep->link_frequencies),
                                      GFP_KERNEL);
                if (!vep->link_frequencies)
                        return -ENOMEM;

                vep->nr_of_link_frequencies = rval;

                rval = fwnode_property_read_u64_array(fwnode,
                                                      "link-frequencies",
                                                      vep->link_frequencies,
                                                      vep->nr_of_link_frequencies);
                if (rval < 0) {
                        v4l2_fwnode_endpoint_free(vep);
                        return rval;
                }

                for (i = 0; i < vep->nr_of_link_frequencies; i++)
                        pr_debug("link-frequencies %u value %llu\n", i,
                                 vep->link_frequencies[i]);
        }

        pr_debug("===== end parsing endpoint %pfw\n", fwnode);

        return 0;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_alloc_parse);

int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode,
                           struct v4l2_fwnode_link *link)
{
        struct fwnode_endpoint fwep;

        memset(link, 0, sizeof(*link));

        fwnode_graph_parse_endpoint(fwnode, &fwep);
        link->local_id = fwep.id;
        link->local_port = fwep.port;
        link->local_node = fwnode_graph_get_port_parent(fwnode);
        if (!link->local_node)
                return -ENOLINK;

        fwnode = fwnode_graph_get_remote_endpoint(fwnode);
        if (!fwnode)
                goto err_put_local_node;

        fwnode_graph_parse_endpoint(fwnode, &fwep);
        link->remote_id = fwep.id;
        link->remote_port = fwep.port;
        link->remote_node = fwnode_graph_get_port_parent(fwnode);
        if (!link->remote_node)
                goto err_put_remote_endpoint;

        return 0;

err_put_remote_endpoint:
        fwnode_handle_put(fwnode);

err_put_local_node:
        fwnode_handle_put(link->local_node);

        return -ENOLINK;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_link);

void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link)
{
        fwnode_handle_put(link->local_node);
        fwnode_handle_put(link->remote_node);
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_put_link);

static const struct v4l2_fwnode_connector_conv {
        enum v4l2_connector_type type;
        const char *compatible;
} connectors[] = {
        {
                .type = V4L2_CONN_COMPOSITE,
                .compatible = "composite-video-connector",
        }, {
                .type = V4L2_CONN_SVIDEO,
                .compatible = "svideo-connector",
        },
};

static enum v4l2_connector_type
v4l2_fwnode_string_to_connector_type(const char *con_str)
{
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(connectors); i++)
                if (!strcmp(con_str, connectors[i].compatible))
                        return connectors[i].type;

        return V4L2_CONN_UNKNOWN;
}

static void
v4l2_fwnode_connector_parse_analog(struct fwnode_handle *fwnode,
                                   struct v4l2_fwnode_connector *vc)
{
        u32 stds;
        int ret;

        ret = fwnode_property_read_u32(fwnode, "sdtv-standards", &stds);

        /* The property is optional. */
        vc->connector.analog.sdtv_stds = ret ? V4L2_STD_ALL : stds;
}

void v4l2_fwnode_connector_free(struct v4l2_fwnode_connector *connector)
{
        struct v4l2_connector_link *link, *tmp;

        if (IS_ERR_OR_NULL(connector) || connector->type == V4L2_CONN_UNKNOWN)
                return;

        list_for_each_entry_safe(link, tmp, &connector->links, head) {
                v4l2_fwnode_put_link(&link->fwnode_link);
                list_del(&link->head);
                kfree(link);
        }

        kfree(connector->label);
        connector->label = NULL;
        connector->type = V4L2_CONN_UNKNOWN;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_connector_free);

static enum v4l2_connector_type
v4l2_fwnode_get_connector_type(struct fwnode_handle *fwnode)
{
        const char *type_name;
        int err;

        if (!fwnode)
                return V4L2_CONN_UNKNOWN;

        /* The connector-type is stored within the compatible string. */
        err = fwnode_property_read_string(fwnode, "compatible", &type_name);
        if (err)
                return V4L2_CONN_UNKNOWN;

        return v4l2_fwnode_string_to_connector_type(type_name);
}

int v4l2_fwnode_connector_parse(struct fwnode_handle *fwnode,
                                struct v4l2_fwnode_connector *connector)
{
        struct fwnode_handle *connector_node;
        enum v4l2_connector_type connector_type;
        const char *label;
        int err;

        if (!fwnode)
                return -EINVAL;

        memset(connector, 0, sizeof(*connector));

        INIT_LIST_HEAD(&connector->links);

        connector_node = fwnode_graph_get_port_parent(fwnode);
        connector_type = v4l2_fwnode_get_connector_type(connector_node);
        if (connector_type == V4L2_CONN_UNKNOWN) {
                fwnode_handle_put(connector_node);
                connector_node = fwnode_graph_get_remote_port_parent(fwnode);
                connector_type = v4l2_fwnode_get_connector_type(connector_node);
        }

        if (connector_type == V4L2_CONN_UNKNOWN) {
                pr_err("Unknown connector type\n");
                err = -ENOTCONN;
                goto out;
        }

        connector->type = connector_type;
        connector->name = fwnode_get_name(connector_node);
        err = fwnode_property_read_string(connector_node, "label", &label);
        connector->label = err ? NULL : kstrdup_const(label, GFP_KERNEL);

        /* Parse the connector specific properties. */
        switch (connector->type) {
        case V4L2_CONN_COMPOSITE:
        case V4L2_CONN_SVIDEO:
                v4l2_fwnode_connector_parse_analog(connector_node, connector);
                break;
        /* Avoid compiler warnings */
        case V4L2_CONN_UNKNOWN:
                break;
        }

out:
        fwnode_handle_put(connector_node);

        return err;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_connector_parse);

int v4l2_fwnode_connector_add_link(struct fwnode_handle *fwnode,
                                   struct v4l2_fwnode_connector *connector)
{
        struct fwnode_handle *connector_ep;
        struct v4l2_connector_link *link;
        int err;

        if (!fwnode || !connector || connector->type == V4L2_CONN_UNKNOWN)
                return -EINVAL;

        connector_ep = fwnode_graph_get_remote_endpoint(fwnode);
        if (!connector_ep)
                return -ENOTCONN;

        link = kzalloc_obj(*link);
        if (!link) {
                err = -ENOMEM;
                goto err;
        }

        err = v4l2_fwnode_parse_link(connector_ep, &link->fwnode_link);
        if (err)
                goto err;

        fwnode_handle_put(connector_ep);

        list_add(&link->head, &connector->links);
        connector->nr_of_links++;

        return 0;

err:
        kfree(link);
        fwnode_handle_put(connector_ep);

        return err;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_connector_add_link);

int v4l2_fwnode_device_parse(struct device *dev,
                             struct v4l2_fwnode_device_properties *props)
{
        struct fwnode_handle *fwnode = dev_fwnode(dev);
        u32 val;
        int ret;

        memset(props, 0, sizeof(*props));

        props->orientation = V4L2_FWNODE_PROPERTY_UNSET;
        ret = fwnode_property_read_u32(fwnode, "orientation", &val);
        if (!ret) {
                switch (val) {
                case V4L2_FWNODE_ORIENTATION_FRONT:
                case V4L2_FWNODE_ORIENTATION_BACK:
                case V4L2_FWNODE_ORIENTATION_EXTERNAL:
                        break;
                default:
                        dev_warn(dev, "Unsupported device orientation: %u\n", val);
                        return -EINVAL;
                }

                props->orientation = val;
                dev_dbg(dev, "device orientation: %u\n", val);
        }

        props->rotation = V4L2_FWNODE_PROPERTY_UNSET;
        ret = fwnode_property_read_u32(fwnode, "rotation", &val);
        if (!ret) {
                if (val >= 360) {
                        dev_warn(dev, "Unsupported device rotation: %u\n", val);
                        return -EINVAL;
                }

                props->rotation = val;
                dev_dbg(dev, "device rotation: %u\n", val);
        }

        return 0;
}
EXPORT_SYMBOL_GPL(v4l2_fwnode_device_parse);

/*
 * v4l2_fwnode_reference_parse - parse references for async sub-devices
 * @dev: the device node the properties of which are parsed for references
 * @notifier: the async notifier where the async subdevs will be added
 * @prop: the name of the property
 *
 * Return: 0 on success
 *         -ENOENT if no entries were found
 *         -ENOMEM if memory allocation failed
 *         -EINVAL if property parsing failed
 */
static int v4l2_fwnode_reference_parse(struct device *dev,
                                       struct v4l2_async_notifier *notifier,
                                       const char *prop)
{
        struct fwnode_reference_args args;
        unsigned int index;
        int ret;

        for (index = 0;
             !(ret = fwnode_property_get_reference_args(dev_fwnode(dev), prop,
                                                        NULL, 0, index, &args));
             index++) {
                struct v4l2_async_connection *asd;

                asd = v4l2_async_nf_add_fwnode(notifier, args.fwnode,
                                               struct v4l2_async_connection);
                fwnode_handle_put(args.fwnode);
                if (IS_ERR(asd)) {
                        /* not an error if asd already exists */
                        if (PTR_ERR(asd) == -EEXIST)
                                continue;

                        return PTR_ERR(asd);
                }
        }

        /* -ENOENT here means successful parsing */
        if (ret != -ENOENT)
                return ret;

        /* Return -ENOENT if no references were found */
        return index ? 0 : -ENOENT;
}

/*
 * v4l2_fwnode_reference_get_int_prop - parse a reference with integer
 *                                      arguments
 * @fwnode: fwnode to read @prop from
 * @notifier: notifier for @dev
 * @prop: the name of the property
 * @index: the index of the reference to get
 * @props: the array of integer property names
 * @nprops: the number of integer property names in @nprops
 *
 * First find an fwnode referred to by the reference at @index in @prop.
 *
 * Then under that fwnode, @nprops times, for each property in @props,
 * iteratively follow child nodes starting from fwnode such that they have the
 * property in @props array at the index of the child node distance from the
 * root node and the value of that property matching with the integer argument
 * of the reference, at the same index.
 *
 * The child fwnode reached at the end of the iteration is then returned to the
 * caller.
 *
 * The core reason for this is that you cannot refer to just any node in ACPI.
 * So to refer to an endpoint (easy in DT) you need to refer to a device, then
 * provide a list of (property name, property value) tuples where each tuple
 * uniquely identifies a child node. The first tuple identifies a child directly
 * underneath the device fwnode, the next tuple identifies a child node
 * underneath the fwnode identified by the previous tuple, etc. until you
 * reached the fwnode you need.
 *
 * THIS EXAMPLE EXISTS MERELY TO DOCUMENT THIS FUNCTION. DO NOT USE IT AS A
 * REFERENCE IN HOW ACPI TABLES SHOULD BE WRITTEN!! See documentation under
 * Documentation/firmware-guide/acpi/dsd/ instead and especially graph.txt,
 * data-node-references.txt and leds.txt .
 *
 *      Scope (\_SB.PCI0.I2C2)
 *      {
 *              Device (CAM0)
 *              {
 *                      Name (_DSD, Package () {
 *                              ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
 *                              Package () {
 *                                      Package () {
 *                                              "compatible",
 *                                              Package () { "nokia,smia" }
 *                                      },
 *                              },
 *                              ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
 *                              Package () {
 *                                      Package () { "port0", "PRT0" },
 *                              }
 *                      })
 *                      Name (PRT0, Package() {
 *                              ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
 *                              Package () {
 *                                      Package () { "port", 0 },
 *                              },
 *                              ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
 *                              Package () {
 *                                      Package () { "endpoint0", "EP00" },
 *                              }
 *                      })
 *                      Name (EP00, Package() {
 *                              ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
 *                              Package () {
 *                                      Package () { "endpoint", 0 },
 *                                      Package () {
 *                                              "remote-endpoint",
 *                                              Package() {
 *                                                      \_SB.PCI0.ISP, 4, 0
 *                                              }
 *                                      },
 *                              }
 *                      })
 *              }
 *      }
 *
 *      Scope (\_SB.PCI0)
 *      {
 *              Device (ISP)
 *              {
 *                      Name (_DSD, Package () {
 *                              ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
 *                              Package () {
 *                                      Package () { "port4", "PRT4" },
 *                              }
 *                      })
 *
 *                      Name (PRT4, Package() {
 *                              ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
 *                              Package () {
 *                                      Package () { "port", 4 },
 *                              },
 *                              ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
 *                              Package () {
 *                                      Package () { "endpoint0", "EP40" },
 *                              }
 *                      })
 *
 *                      Name (EP40, Package() {
 *                              ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
 *                              Package () {
 *                                      Package () { "endpoint", 0 },
 *                                      Package () {
 *                                              "remote-endpoint",
 *                                              Package () {
 *                                                      \_SB.PCI0.I2C2.CAM0,
 *                                                      0, 0
 *                                              }
 *                                      },
 *                              }
 *                      })
 *              }
 *      }
 *
 * From the EP40 node under ISP device, you could parse the graph remote
 * endpoint using v4l2_fwnode_reference_get_int_prop with these arguments:
 *
 *  @fwnode: fwnode referring to EP40 under ISP.
 *  @prop: "remote-endpoint"
 *  @index: 0
 *  @props: "port", "endpoint"
 *  @nprops: 2
 *
 * And you'd get back fwnode referring to EP00 under CAM0.
 *
 * The same works the other way around: if you use EP00 under CAM0 as the
 * fwnode, you'll get fwnode referring to EP40 under ISP.
 *
 * The same example in DT syntax would look like this:
 *
 * cam: cam0 {
 *      compatible = "nokia,smia";
 *
 *      port {
 *              port = <0>;
 *              endpoint {
 *                      endpoint = <0>;
 *                      remote-endpoint = <&isp 4 0>;
 *              };
 *      };
 * };
 *
 * isp: isp {
 *      ports {
 *              port@4 {
 *                      port = <4>;
 *                      endpoint {
 *                              endpoint = <0>;
 *                              remote-endpoint = <&cam 0 0>;
 *                      };
 *              };
 *      };
 * };
 *
 * Return: 0 on success
 *         -ENOENT if no entries (or the property itself) were found
 *         -EINVAL if property parsing otherwise failed
 *         -ENOMEM if memory allocation failed
 */
static struct fwnode_handle *
v4l2_fwnode_reference_get_int_prop(struct fwnode_handle *fwnode,
                                   const char *prop,
                                   unsigned int index,
                                   const char * const *props,
                                   unsigned int nprops)
{
        struct fwnode_reference_args fwnode_args;
        u64 *args = fwnode_args.args;
        struct fwnode_handle *child;
        int ret;

        /*
         * Obtain remote fwnode as well as the integer arguments.
         *
         * Note that right now both -ENODATA and -ENOENT may signal
         * out-of-bounds access. Return -ENOENT in that case.
         */
        ret = fwnode_property_get_reference_args(fwnode, prop, NULL, nprops,
                                                 index, &fwnode_args);
        if (ret)
                return ERR_PTR(ret == -ENODATA ? -ENOENT : ret);

        /*
         * Find a node in the tree under the referred fwnode corresponding to
         * the integer arguments.
         */
        fwnode = fwnode_args.fwnode;
        while (nprops--) {
                u32 val;

                /* Loop over all child nodes under fwnode. */
                fwnode_for_each_child_node(fwnode, child) {
                        if (fwnode_property_read_u32(child, *props, &val))
                                continue;

                        /* Found property, see if its value matches. */
                        if (val == *args)
                                break;
                }

                fwnode_handle_put(fwnode);

                /* No property found; return an error here. */
                if (!child) {
                        fwnode = ERR_PTR(-ENOENT);
                        break;
                }

                props++;
                args++;
                fwnode = child;
        }

        return fwnode;
}

struct v4l2_fwnode_int_props {
        const char *name;
        const char * const *props;
        unsigned int nprops;
};

/*
 * v4l2_fwnode_reference_parse_int_props - parse references for async
 *                                         sub-devices
 * @dev: struct device pointer
 * @notifier: notifier for @dev
 * @prop: the name of the property
 * @props: the array of integer property names
 * @nprops: the number of integer properties
 *
 * Use v4l2_fwnode_reference_get_int_prop to find fwnodes through reference in
 * property @prop with integer arguments with child nodes matching in properties
 * @props. Then, set up V4L2 async sub-devices for those fwnodes in the notifier
 * accordingly.
 *
 * While it is technically possible to use this function on DT, it is only
 * meaningful on ACPI. On Device tree you can refer to any node in the tree but
 * on ACPI the references are limited to devices.
 *
 * Return: 0 on success
 *         -ENOENT if no entries (or the property itself) were found
 *         -EINVAL if property parsing otherwisefailed
 *         -ENOMEM if memory allocation failed
 */
static int
v4l2_fwnode_reference_parse_int_props(struct device *dev,
                                      struct v4l2_async_notifier *notifier,
                                      const struct v4l2_fwnode_int_props *p)
{
        struct fwnode_handle *fwnode;
        unsigned int index;
        int ret;
        const char *prop = p->name;
        const char * const *props = p->props;
        unsigned int nprops = p->nprops;

        index = 0;
        do {
                fwnode = v4l2_fwnode_reference_get_int_prop(dev_fwnode(dev),
                                                            prop, index,
                                                            props, nprops);
                if (IS_ERR(fwnode)) {
                        /*
                         * Note that right now both -ENODATA and -ENOENT may
                         * signal out-of-bounds access. Return the error in
                         * cases other than that.
                         */
                        if (PTR_ERR(fwnode) != -ENOENT &&
                            PTR_ERR(fwnode) != -ENODATA)
                                return PTR_ERR(fwnode);
                        break;
                }
                fwnode_handle_put(fwnode);
                index++;
        } while (1);

        for (index = 0;
             !IS_ERR((fwnode = v4l2_fwnode_reference_get_int_prop(dev_fwnode(dev),
                                                                  prop, index,
                                                                  props,
                                                                  nprops)));
             index++) {
                struct v4l2_async_connection *asd;

                asd = v4l2_async_nf_add_fwnode(notifier, fwnode,
                                               struct v4l2_async_connection);
                fwnode_handle_put(fwnode);
                if (IS_ERR(asd)) {
                        ret = PTR_ERR(asd);
                        /* not an error if asd already exists */
                        if (ret == -EEXIST)
                                continue;

                        return PTR_ERR(asd);
                }
        }

        return !fwnode || PTR_ERR(fwnode) == -ENOENT ? 0 : PTR_ERR(fwnode);
}

/**
 * v4l2_async_nf_parse_fwnode_sensor - parse common references on
 *                                           sensors for async sub-devices
 * @dev: the device node the properties of which are parsed for references
 * @notifier: the async notifier where the async subdevs will be added
 *
 * Parse common sensor properties for remote devices related to the
 * sensor and set up async sub-devices for them.
 *
 * Any notifier populated using this function must be released with a call to
 * v4l2_async_nf_release() after it has been unregistered and the async
 * sub-devices are no longer in use, even in the case the function returned an
 * error.
 *
 * Return: 0 on success
 *         -ENOMEM if memory allocation failed
 *         -EINVAL if property parsing failed
 */
static int
v4l2_async_nf_parse_fwnode_sensor(struct device *dev,
                                  struct v4l2_async_notifier *notifier)
{
        static const char * const led_props[] = { "led" };
        static const struct v4l2_fwnode_int_props props[] = {
                { "flash-leds", led_props, ARRAY_SIZE(led_props) },
                { "mipi-img-flash-leds", },
                { "lens-focus", },
                { "mipi-img-lens-focus", },
        };
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(props); i++) {
                int ret;

                if (props[i].props && is_acpi_node(dev_fwnode(dev)))
                        ret = v4l2_fwnode_reference_parse_int_props(dev,
                                                                    notifier,
                                                                    &props[i]);
                else
                        ret = v4l2_fwnode_reference_parse(dev, notifier,
                                                          props[i].name);
                if (ret && ret != -ENOENT) {
                        dev_warn(dev, "parsing property \"%s\" failed (%d)\n",
                                 props[i].name, ret);
                        return ret;
                }
        }

        return 0;
}

int v4l2_async_register_subdev_sensor(struct v4l2_subdev *sd)
{
        struct v4l2_async_notifier *notifier;
        int ret;

        if (WARN_ON(!sd->dev))
                return -ENODEV;

        notifier = kzalloc_obj(*notifier);
        if (!notifier)
                return -ENOMEM;

        v4l2_async_subdev_nf_init(notifier, sd);

        ret = v4l2_subdev_get_privacy_led(sd);
        if (ret < 0)
                goto out_cleanup;

        ret = v4l2_async_nf_parse_fwnode_sensor(sd->dev, notifier);
        if (ret < 0)
                goto out_cleanup;

        ret = v4l2_async_nf_register(notifier);
        if (ret < 0)
                goto out_cleanup;

        ret = v4l2_async_register_subdev(sd);
        if (ret < 0)
                goto out_unregister;

        sd->subdev_notifier = notifier;

        return 0;

out_unregister:
        v4l2_async_nf_unregister(notifier);

out_cleanup:
        v4l2_subdev_put_privacy_led(sd);
        v4l2_async_nf_cleanup(notifier);
        kfree(notifier);

        return ret;
}
EXPORT_SYMBOL_GPL(v4l2_async_register_subdev_sensor);

MODULE_DESCRIPTION("V4L2 fwnode binding parsing library");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Sakari Ailus <sakari.ailus@linux.intel.com>");
MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");