1 // SPDX-License-Identifier: MIT
2 /*
3 * Copyright © 2019 Intel Corporation
4 */
5
6 #include <linux/vga_switcheroo.h>
7
8 #include "i915_drv.h"
9 #include "i915_switcheroo.h"
10
i915_switcheroo_set_state(struct pci_dev * pdev,enum vga_switcheroo_state state)11 static void i915_switcheroo_set_state(struct pci_dev *pdev,
12 enum vga_switcheroo_state state)
13 {
14 struct drm_i915_private *i915 = pdev_to_i915(pdev);
15 pm_message_t pmm = { .event = PM_EVENT_SUSPEND };
16
17 if (!i915) {
18 dev_err(&pdev->dev, "DRM not initialized, aborting switch.\n");
19 return;
20 }
21 if (!HAS_DISPLAY(i915)) {
22 dev_err(&pdev->dev, "Device state not initialized, aborting switch.\n");
23 return;
24 }
25
26 if (state == VGA_SWITCHEROO_ON) {
27 drm_info(&i915->drm, "switched on\n");
28 i915->drm.switch_power_state = DRM_SWITCH_POWER_CHANGING;
29 /* i915 resume handler doesn't set to D0 */
30 pci_set_power_state(pdev, PCI_D0);
31 i915_resume_switcheroo(i915);
32 i915->drm.switch_power_state = DRM_SWITCH_POWER_ON;
33 } else {
34 drm_info(&i915->drm, "switched off\n");
35 i915->drm.switch_power_state = DRM_SWITCH_POWER_CHANGING;
36 i915_suspend_switcheroo(i915, pmm);
37 i915->drm.switch_power_state = DRM_SWITCH_POWER_OFF;
38 }
39 }
40
i915_switcheroo_can_switch(struct pci_dev * pdev)41 static bool i915_switcheroo_can_switch(struct pci_dev *pdev)
42 {
43 struct drm_i915_private *i915 = pdev_to_i915(pdev);
44
45 /*
46 * FIXME: open_count is protected by drm_global_mutex but that would lead to
47 * locking inversion with the driver load path. And the access here is
48 * completely racy anyway. So don't bother with locking for now.
49 */
50 return i915 && HAS_DISPLAY(i915) && atomic_read(&i915->drm.open_count) == 0;
51 }
52
53 static const struct vga_switcheroo_client_ops i915_switcheroo_ops = {
54 .set_gpu_state = i915_switcheroo_set_state,
55 .reprobe = NULL,
56 .can_switch = i915_switcheroo_can_switch,
57 };
58
i915_switcheroo_register(struct drm_i915_private * i915)59 int i915_switcheroo_register(struct drm_i915_private *i915)
60 {
61 struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
62
63 return vga_switcheroo_register_client(pdev, &i915_switcheroo_ops, false);
64 }
65
i915_switcheroo_unregister(struct drm_i915_private * i915)66 void i915_switcheroo_unregister(struct drm_i915_private *i915)
67 {
68 struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
69
70 vga_switcheroo_unregister_client(pdev);
71 }
72