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
i915_switcheroo_set_state(struct pci_dev * pdev,enum vga_switcheroo_state state)12 static 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
i915_switcheroo_can_switch(struct pci_dev * pdev)42 static 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
54 static 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
i915_switcheroo_register(struct drm_i915_private * i915)60 int 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
i915_switcheroo_unregister(struct drm_i915_private * i915)67 void 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