static int nouveau_pmops_runtime_suspend(struct device *dev)
{
	struct pci_dev *pdev = to_pci_dev(dev);
	struct drm_device *drm_dev = pci_get_drvdata(pdev);
	int ret;

	if (nouveau_runtime_pm == 0) {
		pm_runtime_forbid(dev);
		return -EBUSY;
	}

	/* are we optimus enabled? */
	if (nouveau_runtime_pm == -1 && !nouveau_is_optimus() && !nouveau_is_v1_dsm()) {
		DRM_DEBUG_DRIVER("failing to power off - not optimus\n");
		pm_runtime_forbid(dev);
		return -EBUSY;
	}

	nv_debug_level(SILENT);
	drm_kms_helper_poll_disable(drm_dev);
	vga_switcheroo_set_dynamic_switch(pdev, VGA_SWITCHEROO_OFF);
	nouveau_switcheroo_optimus_dsm();
	ret = nouveau_do_suspend(drm_dev, true);
	pci_save_state(pdev);
	pci_disable_device(pdev);
	pci_set_power_state(pdev, PCI_D3cold);
	drm_dev->switch_power_state = DRM_SWITCH_POWER_DYNAMIC_OFF;
	return ret;
}

0000000000000855 <nouveau_pmops_runtime_suspend>:
     855:       e8 00 00 00 00          callq  85a <nouveau_pci_name+0x85a>
                        856: R_X86_64_PC32      __fentry__-0x4
     85a:       55                      push   %rbp
     85b:       48 89 e5                mov    %rsp,%rbp
     85e:       41 55                   push   %r13
     860:       41 54                   push   %r12
     862:       4c 8d a7 68 ff ff ff    lea    -0x98(%rdi),%r12
     869:       53                      push   %rbx
     86a:       48 89 fb                mov    %rdi,%rbx
     86d:       51                      push   %rcx
     86e:       8b 05 00 00 00 00       mov    0x0(%rip),%eax        # 874 <nouveau_pci_name+0x874>
                        870: R_X86_64_PC32      nouveau_runtime_pm-0x4
     874:       4c 8b af a0 00 00 00    mov    0xa0(%rdi),%r13
     87b:       85 c0                   test   %eax,%eax
     87d:       75 12                   jne    891 <nouveau_pci_name+0x891>
 +-> 87f:       48 89 df                mov    %rbx,%rdi
 |
###############
###############
 |   882:       e8 00 00 00 00          callq  887 <nouveau_pci_name+0x887>
 |                      883: R_X86_64_PC32      pm_runtime_forbid-0x4
###############
###############
 |   887:       b8 f0 ff ff ff          mov    $0xfffffff0,%eax
 |   88c:       e9 8e 00 00 00          jmpq   91f <nouveau_pci_name+0x91f>
 ^   891:       ff c0                   inc    %eax
 |   893:       75 30                   jne    8c5 <nouveau_pci_name+0x8c5>
 |   895:       e8 00 00 00 00          callq  89a <nouveau_pci_name+0x89a>
                        896: R_X86_64_PC32      nouveau_is_optimus-0x4
     89a:       84 c0                   test   %al,%al
     89c:       75 27                   jne    8c5 <nouveau_pci_name+0x8c5>
     89e:       e8 00 00 00 00          callq  8a3 <nouveau_pci_name+0x8a3>
                        89f: R_X86_64_PC32      nouveau_is_v1_dsm-0x4
     8a3:       84 c0                   test   %al,%al
     8a5:       75 1e                   jne    8c5 <nouveau_pci_name+0x8c5>
     8a7:       f6 05 00 00 00 00 02    testb  $0x2,0x0(%rip)        # 8ae <nouveau_pci_name+0x8ae>
                        8a9: R_X86_64_PC32      drm_debug-0x5
     8ae:       74 cf                   je     87f <nouveau_pci_name+0x87f>
     8b0:       48 c7 c6 00 00 00 00    mov    $0x0,%rsi
 ^                      8b3: R_X86_64_32S       .rodata.str1.1+0x135
 |   8b7:       48 c7 c7 00 00 00 00    mov    $0x0,%rdi
 |                      8ba: R_X86_64_32S       .rodata+0x20
 |   8be:       e8 00 00 00 00          callq  8c3 <nouveau_pci_name+0x8c3>
 |                      8bf: R_X86_64_PC32      drm_ut_debug_printk-0x4
 ^-  8c3:       eb ba                   jmp    87f <nouveau_pci_name+0x87f>
     8c5:       c7 05 00 00 00 00 04    movl   $0x4,0x0(%rip)        # 8cf <nouveau_pci_name+0x8cf>
     8cc:       00 00 00
                        8c7: R_X86_64_PC32      nv_info_debug_level-0x8
     8cf:       4c 89 ef                mov    %r13,%rdi
     8d2:       e8 00 00 00 00          callq  8d7 <nouveau_pci_name+0x8d7>
                        8d3: R_X86_64_PC32      drm_kms_helper_poll_disable-0x4
     8d7:       31 f6                   xor    %esi,%esi
     8d9:       4c 89 e7                mov    %r12,%rdi
     8dc:       e8 00 00 00 00          callq  8e1 <nouveau_pci_name+0x8e1>
                        8dd: R_X86_64_PC32      vga_switcheroo_set_dynamic_switch-0x4
     8e1:       e8 00 00 00 00          callq  8e6 <nouveau_pci_name+0x8e6>
                        8e2: R_X86_64_PC32      nouveau_switcheroo_optimus_dsm-0x4
     8e6:       be 01 00 00 00          mov    $0x1,%esi
     8eb:       4c 89 ef                mov    %r13,%rdi
     8ee:       e8 f4 f7 ff ff          callq  e7 <nouveau_pci_name+0xe7>
     8f3:       4c 89 e7                mov    %r12,%rdi
     8f6:       89 c3                   mov    %eax,%ebx
     8f6:       89 c3                   mov    %eax,%ebx
     8f8:       e8 00 00 00 00          callq  8fd <nouveau_pci_name+0x8fd>
                        8f9: R_X86_64_PC32      pci_save_state-0x4
     8fd:       4c 89 e7                mov    %r12,%rdi
     900:       e8 00 00 00 00          callq  905 <nouveau_pci_name+0x905>
                        901: R_X86_64_PC32      pci_disable_device-0x4
     905:       be 04 00 00 00          mov    $0x4,%esi
     90a:       4c 89 e7                mov    %r12,%rdi
     90d:       e8 00 00 00 00          callq  912 <nouveau_pci_name+0x912>
                        90e: R_X86_64_PC32      pci_set_power_state-0x4
     912:       89 d8                   mov    %ebx,%eax
     914:       41 c7 85 60 05 00 00    movl   $0x3,0x560(%r13)
     91b:       03 00 00 00
     91f:       5a                      pop    %rdx
     920:       5b                      pop    %rbx
     921:       41 5c                   pop    %r12
     923:       41 5d                   pop    %r13
     925:       5d                      pop    %rbp
     926:       c3                      retq