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 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 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 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 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