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
22 if (state == VGA_SWITCHEROO_ON) {
23 drm_info(&i915->drm, "switched on\n");
24 i915->drm.switch_power_state = DRM_SWITCH_POWER_CHANGING;
25 /* i915 resume handler doesn't set to D0 */
26 pci_set_power_state(pdev, PCI_D0);
27 i915_resume_switcheroo(i915);
28 i915->drm.switch_power_state = DRM_SWITCH_POWER_ON;
29 } else {
30 drm_info(&i915->drm, "switched off\n");
31 i915->drm.switch_power_state = DRM_SWITCH_POWER_CHANGING;
32 i915_suspend_switcheroo(i915, pmm);
33 i915->drm.switch_power_state = DRM_SWITCH_POWER_OFF;
34 }
35 }
36
i915_switcheroo_can_switch(struct pci_dev * pdev)37 static bool i915_switcheroo_can_switch(struct pci_dev *pdev)
38 {
39 struct drm_i915_private *i915 = pdev_to_i915(pdev);
40
41 /*
42 * FIXME: open_count is protected by drm_global_mutex but that would lead to
43 * locking inversion with the driver load path. And the access here is
44 * completely racy anyway. So don't bother with locking for now.
45 */
46 return i915 && atomic_read(&i915->drm.open_count) == 0;
47 }
48
49 static const struct vga_switcheroo_client_ops i915_switcheroo_ops = {
50 .set_gpu_state = i915_switcheroo_set_state,
51 .reprobe = NULL,
52 .can_switch = i915_switcheroo_can_switch,
53 };
54
i915_switcheroo_register(struct drm_i915_private * i915)55 int i915_switcheroo_register(struct drm_i915_private *i915)
56 {
57 struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
58
59 return vga_switcheroo_register_client(pdev, &i915_switcheroo_ops, false);
60 }
61
i915_switcheroo_unregister(struct drm_i915_private * i915)62 void i915_switcheroo_unregister(struct drm_i915_private *i915)
63 {
64 struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
65
66 vga_switcheroo_unregister_client(pdev);
67 }
68