// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012 Avionic Design GmbH
 * Copyright (C) 2012 NVIDIA CORPORATION.  All rights reserved.
 */

#include <linux/i2c.h>
#include <linux/of.h>

#include <drm/drm_atomic_helper.h>
#include <drm/drm_edid.h>
#include <drm/drm_of.h>
#include <drm/drm_panel.h>
#include <drm/drm_simple_kms_helper.h>

#include "drm.h"
#include "dc.h"

#include <media/cec-notifier.h>

int tegra_output_connector_get_modes(struct drm_connector *connector)
{
        struct tegra_output *output = connector_to_output(connector);
        const struct drm_edid *drm_edid = NULL;
        int err = 0;

        /*
         * If the panel provides one or more modes, use them exclusively and
         * ignore any other means of obtaining a mode.
         */
        if (output->panel) {
                err = drm_panel_get_modes(output->panel, connector);
                if (err > 0)
                        return err;
        }

        if (output->drm_edid)
                drm_edid = drm_edid_dup(output->drm_edid);
        else if (output->ddc)
                drm_edid = drm_edid_read_ddc(connector, output->ddc);

        drm_edid_connector_update(connector, drm_edid);
        cec_notifier_set_phys_addr(output->cec,
                                   connector->display_info.source_physical_address);

        err = drm_edid_connector_add_modes(connector);
        drm_edid_free(drm_edid);

        return err;
}

enum drm_connector_status
tegra_output_connector_detect(struct drm_connector *connector, bool force)
{
        struct tegra_output *output = connector_to_output(connector);
        enum drm_connector_status status = connector_status_unknown;

        if (output->hpd_gpio) {
                if (gpiod_get_value(output->hpd_gpio) == 0)
                        status = connector_status_disconnected;
                else
                        status = connector_status_connected;
        } else {
                if (!output->panel)
                        status = connector_status_disconnected;
                else
                        status = connector_status_connected;
        }

        if (status != connector_status_connected)
                cec_notifier_phys_addr_invalidate(output->cec);

        return status;
}

void tegra_output_connector_destroy(struct drm_connector *connector)
{
        struct tegra_output *output = connector_to_output(connector);

        if (output->cec)
                cec_notifier_conn_unregister(output->cec);

        drm_connector_unregister(connector);
        drm_connector_cleanup(connector);
}

static irqreturn_t hpd_irq(int irq, void *data)
{
        struct tegra_output *output = data;

        if (output->connector.dev)
                drm_helper_hpd_irq_event(output->connector.dev);

        return IRQ_HANDLED;
}

int tegra_output_probe(struct tegra_output *output)
{
        struct device_node *ddc, *panel;
        const void *edid;
        unsigned long flags;
        int err, size;

        if (!output->of_node)
                output->of_node = output->dev->of_node;

        err = drm_of_find_panel_or_bridge(output->of_node, -1, -1,
                                          &output->panel, &output->bridge);
        if (err && err != -ENODEV)
                return err;

        panel = of_parse_phandle(output->of_node, "nvidia,panel", 0);
        if (panel) {
                /*
                 * Don't mix nvidia,panel phandle with the graph in a
                 * device-tree.
                 */
                WARN_ON(output->panel || output->bridge);

                output->panel = of_drm_find_panel(panel);
                of_node_put(panel);

                if (IS_ERR(output->panel))
                        return PTR_ERR(output->panel);
        }

        ddc = of_parse_phandle(output->of_node, "nvidia,ddc-i2c-bus", 0);
        if (ddc) {
                output->ddc = of_get_i2c_adapter_by_node(ddc);
                of_node_put(ddc);

                if (!output->ddc) {
                        err = -EPROBE_DEFER;
                        return err;
                }
        }

        edid = of_get_property(output->of_node, "nvidia,edid", &size);
        output->drm_edid = drm_edid_alloc(edid, size);

        output->hpd_gpio = devm_fwnode_gpiod_get(output->dev,
                                        of_fwnode_handle(output->of_node),
                                        "nvidia,hpd",
                                        GPIOD_IN,
                                        "HDMI hotplug detect");
        if (IS_ERR(output->hpd_gpio)) {
                if (PTR_ERR(output->hpd_gpio) != -ENOENT) {
                        err = PTR_ERR(output->hpd_gpio);
                        goto put_i2c;
                }

                output->hpd_gpio = NULL;
        }

        if (output->hpd_gpio) {
                err = gpiod_to_irq(output->hpd_gpio);
                if (err < 0) {
                        dev_err(output->dev, "gpiod_to_irq(): %d\n", err);
                        goto put_i2c;
                }

                output->hpd_irq = err;

                flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
                        IRQF_ONESHOT;

                err = request_threaded_irq(output->hpd_irq, NULL, hpd_irq,
                                           flags, "hpd", output);
                if (err < 0) {
                        dev_err(output->dev, "failed to request IRQ#%u: %d\n",
                                output->hpd_irq, err);
                        goto put_i2c;
                }

                output->connector.polled = DRM_CONNECTOR_POLL_HPD;

                /*
                 * Disable the interrupt until the connector has been
                 * initialized to avoid a race in the hotplug interrupt
                 * handler.
                 */
                disable_irq(output->hpd_irq);
        }

        return 0;

put_i2c:
        if (output->ddc)
                i2c_put_adapter(output->ddc);

        drm_edid_free(output->drm_edid);

        return err;
}

void tegra_output_remove(struct tegra_output *output)
{
        if (output->hpd_gpio)
                free_irq(output->hpd_irq, output);

        if (output->ddc)
                i2c_put_adapter(output->ddc);

        drm_edid_free(output->drm_edid);
}

int tegra_output_init(struct drm_device *drm, struct tegra_output *output)
{
        int connector_type;

        /*
         * The connector is now registered and ready to receive hotplug events
         * so the hotplug interrupt can be enabled.
         */
        if (output->hpd_gpio)
                enable_irq(output->hpd_irq);

        connector_type = output->connector.connector_type;
        /*
         * Create a CEC notifier for HDMI connector.
         */
        if (connector_type == DRM_MODE_CONNECTOR_HDMIA ||
            connector_type == DRM_MODE_CONNECTOR_HDMIB) {
                struct cec_connector_info conn_info;

                cec_fill_conn_info_from_drm(&conn_info, &output->connector);
                output->cec = cec_notifier_conn_register(output->dev, NULL,
                                                         &conn_info);
                if (!output->cec)
                        return -ENOMEM;
        }

        return 0;
}

void tegra_output_exit(struct tegra_output *output)
{
        /*
         * The connector is going away, so the interrupt must be disabled to
         * prevent the hotplug interrupt handler from potentially crashing.
         */
        if (output->hpd_gpio)
                disable_irq(output->hpd_irq);
}

void tegra_output_find_possible_crtcs(struct tegra_output *output,
                                      struct drm_device *drm)
{
        struct device *dev = output->dev;
        struct drm_crtc *crtc;
        unsigned int mask = 0;

        drm_for_each_crtc(crtc, drm) {
                struct tegra_dc *dc = to_tegra_dc(crtc);

                if (tegra_dc_has_output(dc, dev))
                        mask |= drm_crtc_mask(crtc);
        }

        if (mask == 0) {
                dev_warn(dev, "missing output definition for heads in DT\n");
                mask = 0x3;
        }

        output->encoder.possible_crtcs = mask;
}

int tegra_output_suspend(struct tegra_output *output)
{
        if (output->hpd_irq)
                disable_irq(output->hpd_irq);

        return 0;
}

int tegra_output_resume(struct tegra_output *output)
{
        if (output->hpd_irq)
                enable_irq(output->hpd_irq);

        return 0;
}