// SPDX-License-Identifier: MIT
/*
 * Copyright © 2019 Intel Corporation
 */

#include <linux/vga_switcheroo.h>

#include "display/intel_display_device.h"

#include "i915_driver.h"
#include "i915_drv.h"
#include "i915_switcheroo.h"

#ifdef notyet

static void i915_switcheroo_set_state(struct pci_dev *pdev,
                                      enum vga_switcheroo_state state)
{
        struct drm_i915_private *i915 = pdev_to_i915(pdev);
        struct intel_display *display = i915 ? i915->display : NULL;
        pm_message_t pmm = { .event = PM_EVENT_SUSPEND };

        if (!i915) {
                dev_err(&pdev->dev, "DRM not initialized, aborting switch.\n");
                return;
        }
        if (!intel_display_device_present(display)) {
                dev_err(&pdev->dev, "Device state not initialized, aborting switch.\n");
                return;
        }

        if (state == VGA_SWITCHEROO_ON) {
                drm_info(&i915->drm, "switched on\n");
                i915->drm.switch_power_state = DRM_SWITCH_POWER_CHANGING;
                /* i915 resume handler doesn't set to D0 */
                pci_set_power_state(pdev, PCI_D0);
                i915_driver_resume_switcheroo(i915);
                i915->drm.switch_power_state = DRM_SWITCH_POWER_ON;
        } else {
                drm_info(&i915->drm, "switched off\n");
                i915->drm.switch_power_state = DRM_SWITCH_POWER_CHANGING;
                i915_driver_suspend_switcheroo(i915, pmm);
                i915->drm.switch_power_state = DRM_SWITCH_POWER_OFF;
        }
}

static bool i915_switcheroo_can_switch(struct pci_dev *pdev)
{
        struct drm_i915_private *i915 = pdev_to_i915(pdev);
        struct intel_display *display = i915 ? i915->display : NULL;

        /*
         * FIXME: open_count is protected by drm_global_mutex but that would lead to
         * locking inversion with the driver load path. And the access here is
         * completely racy anyway. So don't bother with locking for now.
         */
        return i915 && intel_display_device_present(display) &&
                atomic_read(&i915->drm.open_count) == 0;
}

static const struct vga_switcheroo_client_ops i915_switcheroo_ops = {
        .set_gpu_state = i915_switcheroo_set_state,
        .reprobe = NULL,
        .can_switch = i915_switcheroo_can_switch,
};

#endif /* notyet */

int i915_switcheroo_register(struct drm_i915_private *i915)
{
#ifdef notyet
        struct pci_dev *pdev = to_pci_dev(i915->drm.dev);

        return vga_switcheroo_register_client(pdev, &i915_switcheroo_ops, false);
#else
        return 0;
#endif
}

void i915_switcheroo_unregister(struct drm_i915_private *i915)
{
#ifdef notyet
        struct pci_dev *pdev = to_pci_dev(i915->drm.dev);

        vga_switcheroo_unregister_client(pdev);
#endif
}