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 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 pr_info("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 pr_info("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 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 55 int i915_switcheroo_register(struct drm_i915_private *i915) 56 { 57 struct pci_dev *pdev = i915->drm.pdev; 58 59 return vga_switcheroo_register_client(pdev, &i915_switcheroo_ops, false); 60 } 61 62 void i915_switcheroo_unregister(struct drm_i915_private *i915) 63 { 64 struct pci_dev *pdev = i915->drm.pdev; 65 66 vga_switcheroo_unregister_client(pdev); 67 } 68