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5
6#include <linux/pci.h>
7#include <linux/acpi.h>
8#include <drm/drmP.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 struct intel_dsm_priv {
15 acpi_handle dhandle;
16} intel_dsm_priv;
17
18static const u8 intel_dsm_guid[] = {
19 0xd3, 0x73, 0xd8, 0x7e,
20 0xd0, 0xc2,
21 0x4f, 0x4e,
22 0xa8, 0x54,
23 0x0f, 0x13, 0x17, 0xb0, 0x1c, 0x2c
24};
25
26static char *intel_dsm_port_name(u8 id)
27{
28 switch (id) {
29 case 0:
30 return "Reserved";
31 case 1:
32 return "Analog VGA";
33 case 2:
34 return "LVDS";
35 case 3:
36 return "Reserved";
37 case 4:
38 return "HDMI/DVI_B";
39 case 5:
40 return "HDMI/DVI_C";
41 case 6:
42 return "HDMI/DVI_D";
43 case 7:
44 return "DisplayPort_A";
45 case 8:
46 return "DisplayPort_B";
47 case 9:
48 return "DisplayPort_C";
49 case 0xa:
50 return "DisplayPort_D";
51 case 0xb:
52 case 0xc:
53 case 0xd:
54 return "Reserved";
55 case 0xe:
56 return "WiDi";
57 default:
58 return "bad type";
59 }
60}
61
62static char *intel_dsm_mux_type(u8 type)
63{
64 switch (type) {
65 case 0:
66 return "unknown";
67 case 1:
68 return "No MUX, iGPU only";
69 case 2:
70 return "No MUX, dGPU only";
71 case 3:
72 return "MUXed between iGPU and dGPU";
73 default:
74 return "bad type";
75 }
76}
77
78static void intel_dsm_platform_mux_info(void)
79{
80 int i;
81 union acpi_object *pkg, *connector_count;
82
83 pkg = acpi_evaluate_dsm_typed(intel_dsm_priv.dhandle, intel_dsm_guid,
84 INTEL_DSM_REVISION_ID, INTEL_DSM_FN_PLATFORM_MUX_INFO,
85 NULL, ACPI_TYPE_PACKAGE);
86 if (!pkg) {
87 DRM_DEBUG_DRIVER("failed to evaluate _DSM\n");
88 return;
89 }
90
91 connector_count = &pkg->package.elements[0];
92 DRM_DEBUG_DRIVER("MUX info connectors: %lld\n",
93 (unsigned long long)connector_count->integer.value);
94 for (i = 1; i < pkg->package.count; i++) {
95 union acpi_object *obj = &pkg->package.elements[i];
96 union acpi_object *connector_id = &obj->package.elements[0];
97 union acpi_object *info = &obj->package.elements[1];
98 DRM_DEBUG_DRIVER("Connector id: 0x%016llx\n",
99 (unsigned long long)connector_id->integer.value);
100 DRM_DEBUG_DRIVER(" port id: %s\n",
101 intel_dsm_port_name(info->buffer.pointer[0]));
102 DRM_DEBUG_DRIVER(" display mux info: %s\n",
103 intel_dsm_mux_type(info->buffer.pointer[1]));
104 DRM_DEBUG_DRIVER(" aux/dc mux info: %s\n",
105 intel_dsm_mux_type(info->buffer.pointer[2]));
106 DRM_DEBUG_DRIVER(" hpd mux info: %s\n",
107 intel_dsm_mux_type(info->buffer.pointer[3]));
108 }
109
110 ACPI_FREE(pkg);
111}
112
113static bool intel_dsm_pci_probe(struct pci_dev *pdev)
114{
115 acpi_handle dhandle;
116
117 dhandle = ACPI_HANDLE(&pdev->dev);
118 if (!dhandle)
119 return false;
120
121 if (!acpi_check_dsm(dhandle, intel_dsm_guid, INTEL_DSM_REVISION_ID,
122 1 << INTEL_DSM_FN_PLATFORM_MUX_INFO)) {
123 DRM_DEBUG_KMS("no _DSM method for intel device\n");
124 return false;
125 }
126
127 intel_dsm_priv.dhandle = dhandle;
128 intel_dsm_platform_mux_info();
129
130 return true;
131}
132
133static bool intel_dsm_detect(void)
134{
135 char acpi_method_name[255] = { 0 };
136 struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
137 struct pci_dev *pdev = NULL;
138 bool has_dsm = false;
139 int vga_count = 0;
140
141 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
142 vga_count++;
143 has_dsm |= intel_dsm_pci_probe(pdev);
144 }
145
146 if (vga_count == 2 && has_dsm) {
147 acpi_get_name(intel_dsm_priv.dhandle, ACPI_FULL_PATHNAME, &buffer);
148 DRM_DEBUG_DRIVER("vga_switcheroo: detected DSM switching method %s handle\n",
149 acpi_method_name);
150 return true;
151 }
152
153 return false;
154}
155
156void intel_register_dsm_handler(void)
157{
158 if (!intel_dsm_detect())
159 return;
160}
161
162void intel_unregister_dsm_handler(void)
163{
164}
165
