1// SPDX-License-Identifier: MIT
2/*
3 * Copyright �� 2019 Intel Corporation
4 */
5
6#include <linux/vga_switcheroo.h>
7
8#include "i915_driver.h"
9#include "i915_drv.h"
10#include "i915_switcheroo.h"
11
12static void i915_switcheroo_set_state(struct pci_dev *pdev,
13				      enum vga_switcheroo_state state)
14{
15	struct drm_i915_private *i915 = pdev_to_i915(pdev);
16	pm_message_t pmm = { .event = PM_EVENT_SUSPEND };
17
18	if (!i915) {
19		dev_err(&pdev->dev, "DRM not initialized, aborting switch.\n");
20		return;
21	}
22	if (!HAS_DISPLAY(i915)) {
23		dev_err(&pdev->dev, "Device state not initialized, aborting switch.\n");
24		return;
25	}
26
27	if (state == VGA_SWITCHEROO_ON) {
28		drm_info(&i915->drm, "switched on\n");
29		i915->drm.switch_power_state = DRM_SWITCH_POWER_CHANGING;
30		/* i915 resume handler doesn't set to D0 */
31		pci_set_power_state(pdev, PCI_D0);
32		i915_driver_resume_switcheroo(i915);
33		i915->drm.switch_power_state = DRM_SWITCH_POWER_ON;
34	} else {
35		drm_info(&i915->drm, "switched off\n");
36		i915->drm.switch_power_state = DRM_SWITCH_POWER_CHANGING;
37		i915_driver_suspend_switcheroo(i915, pmm);
38		i915->drm.switch_power_state = DRM_SWITCH_POWER_OFF;
39	}
40}
41
42static bool i915_switcheroo_can_switch(struct pci_dev *pdev)
43{
44	struct drm_i915_private *i915 = pdev_to_i915(pdev);
45
46	/*
47	 * FIXME: open_count is protected by drm_global_mutex but that would lead to
48	 * locking inversion with the driver load path. And the access here is
49	 * completely racy anyway. So don't bother with locking for now.
50	 */
51	return i915 && HAS_DISPLAY(i915) && atomic_read(&i915->drm.open_count) == 0;
52}
53
54static const struct vga_switcheroo_client_ops i915_switcheroo_ops = {
55	.set_gpu_state = i915_switcheroo_set_state,
56	.reprobe = NULL,
57	.can_switch = i915_switcheroo_can_switch,
58};
59
60int i915_switcheroo_register(struct drm_i915_private *i915)
61{
62	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
63
64	return vga_switcheroo_register_client(pdev, &i915_switcheroo_ops, false);
65}
66
67void i915_switcheroo_unregister(struct drm_i915_private *i915)
68{
69	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
70
71	vga_switcheroo_unregister_client(pdev);
72}
73