1
2
3
4
5
6
7#include <linux/pci.h>
8#include <linux/acpi.h>
9#include "i915_drv.h"
10
11#define INTEL_DSM_REVISION_ID 1
12#define INTEL_DSM_FN_PLATFORM_MUX_INFO 1
13
14static const guid_t intel_dsm_guid =
15 GUID_INIT(0x7ed873d3, 0xc2d0, 0x4e4f,
16 0xa8, 0x54, 0x0f, 0x13, 0x17, 0xb0, 0x1c, 0x2c);
17
18static char *intel_dsm_port_name(u8 id)
19{
20 switch (id) {
21 case 0:
22 return "Reserved";
23 case 1:
24 return "Analog VGA";
25 case 2:
26 return "LVDS";
27 case 3:
28 return "Reserved";
29 case 4:
30 return "HDMI/DVI_B";
31 case 5:
32 return "HDMI/DVI_C";
33 case 6:
34 return "HDMI/DVI_D";
35 case 7:
36 return "DisplayPort_A";
37 case 8:
38 return "DisplayPort_B";
39 case 9:
40 return "DisplayPort_C";
41 case 0xa:
42 return "DisplayPort_D";
43 case 0xb:
44 case 0xc:
45 case 0xd:
46 return "Reserved";
47 case 0xe:
48 return "WiDi";
49 default:
50 return "bad type";
51 }
52}
53
54static char *intel_dsm_mux_type(u8 type)
55{
56 switch (type) {
57 case 0:
58 return "unknown";
59 case 1:
60 return "No MUX, iGPU only";
61 case 2:
62 return "No MUX, dGPU only";
63 case 3:
64 return "MUXed between iGPU and dGPU";
65 default:
66 return "bad type";
67 }
68}
69
70static void intel_dsm_platform_mux_info(acpi_handle dhandle)
71{
72 int i;
73 union acpi_object *pkg, *connector_count;
74
75 pkg = acpi_evaluate_dsm_typed(dhandle, &intel_dsm_guid,
76 INTEL_DSM_REVISION_ID, INTEL_DSM_FN_PLATFORM_MUX_INFO,
77 NULL, ACPI_TYPE_PACKAGE);
78 if (!pkg) {
79 DRM_DEBUG_DRIVER("failed to evaluate _DSM\n");
80 return;
81 }
82
83 connector_count = &pkg->package.elements[0];
84 DRM_DEBUG_DRIVER("MUX info connectors: %lld\n",
85 (unsigned long long)connector_count->integer.value);
86 for (i = 1; i < pkg->package.count; i++) {
87 union acpi_object *obj = &pkg->package.elements[i];
88 union acpi_object *connector_id = &obj->package.elements[0];
89 union acpi_object *info = &obj->package.elements[1];
90 DRM_DEBUG_DRIVER("Connector id: 0x%016llx\n",
91 (unsigned long long)connector_id->integer.value);
92 DRM_DEBUG_DRIVER(" port id: %s\n",
93 intel_dsm_port_name(info->buffer.pointer[0]));
94 DRM_DEBUG_DRIVER(" display mux info: %s\n",
95 intel_dsm_mux_type(info->buffer.pointer[1]));
96 DRM_DEBUG_DRIVER(" aux/dc mux info: %s\n",
97 intel_dsm_mux_type(info->buffer.pointer[2]));
98 DRM_DEBUG_DRIVER(" hpd mux info: %s\n",
99 intel_dsm_mux_type(info->buffer.pointer[3]));
100 }
101
102 ACPI_FREE(pkg);
103}
104
105static acpi_handle intel_dsm_pci_probe(struct pci_dev *pdev)
106{
107 acpi_handle dhandle;
108
109 dhandle = ACPI_HANDLE(&pdev->dev);
110 if (!dhandle)
111 return NULL;
112
113 if (!acpi_check_dsm(dhandle, &intel_dsm_guid, INTEL_DSM_REVISION_ID,
114 1 << INTEL_DSM_FN_PLATFORM_MUX_INFO)) {
115 DRM_DEBUG_KMS("no _DSM method for intel device\n");
116 return NULL;
117 }
118
119 intel_dsm_platform_mux_info(dhandle);
120
121 return dhandle;
122}
123
124static bool intel_dsm_detect(void)
125{
126 acpi_handle dhandle = NULL;
127 char acpi_method_name[255] = { 0 };
128 struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
129 struct pci_dev *pdev = NULL;
130 int vga_count = 0;
131
132 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
133 vga_count++;
134 dhandle = intel_dsm_pci_probe(pdev) ?: dhandle;
135 }
136
137 if (vga_count == 2 && dhandle) {
138 acpi_get_name(dhandle, ACPI_FULL_PATHNAME, &buffer);
139 DRM_DEBUG_DRIVER("vga_switcheroo: detected DSM switching method %s handle\n",
140 acpi_method_name);
141 return true;
142 }
143
144 return false;
145}
146
147void intel_register_dsm_handler(void)
148{
149 if (!intel_dsm_detect())
150 return;
151}
152
153void intel_unregister_dsm_handler(void)
154{
155}
156
