4 * _DSM related code stolen from nouveau_acpi.c.
7 #include <linux/acpi.h>
8 #include <linux/vga_switcheroo.h>
9 #include <acpi/acpi_drivers.h>
14 #define INTEL_DSM_REVISION_ID 1 /* For Calpella anyway... */
16 #define INTEL_DSM_FN_SUPPORTED_FUNCTIONS 0 /* No args */
17 #define INTEL_DSM_FN_PLATFORM_MUX_INFO 1 /* No args */
19 static struct intel_dsm_priv {
23 static const u8 intel_dsm_guid[] = {
24 0xd3, 0x73, 0xd8, 0x7e,
28 0x0f, 0x13, 0x17, 0xb0, 0x1c, 0x2c
31 static int intel_dsm(acpi_handle handle, int func)
33 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
34 struct acpi_object_list input;
35 union acpi_object params[4];
36 union acpi_object *obj;
41 input.pointer = params;
42 params[0].type = ACPI_TYPE_BUFFER;
43 params[0].buffer.length = sizeof(intel_dsm_guid);
44 params[0].buffer.pointer = (char *)intel_dsm_guid;
45 params[1].type = ACPI_TYPE_INTEGER;
46 params[1].integer.value = INTEL_DSM_REVISION_ID;
47 params[2].type = ACPI_TYPE_INTEGER;
48 params[2].integer.value = func;
49 params[3].type = ACPI_TYPE_PACKAGE;
50 params[3].package.count = 0;
51 params[3].package.elements = NULL;
53 ret = acpi_evaluate_object(handle, "_DSM", &input, &output);
55 DRM_DEBUG_DRIVER("failed to evaluate _DSM: %d\n", ret);
59 obj = (union acpi_object *)output.pointer;
63 case ACPI_TYPE_INTEGER:
64 result = obj->integer.value;
67 case ACPI_TYPE_BUFFER:
68 if (obj->buffer.length == 4) {
69 result = (obj->buffer.pointer[0] |
70 (obj->buffer.pointer[1] << 8) |
71 (obj->buffer.pointer[2] << 16) |
72 (obj->buffer.pointer[3] << 24));
79 if (result == 0x80000002)
82 kfree(output.pointer);
86 static char *intel_dsm_port_name(u8 id)
104 return "DisplayPort_A";
106 return "DisplayPort_B";
108 return "DisplayPort_C";
110 return "DisplayPort_D";
122 static char *intel_dsm_mux_type(u8 type)
128 return "No MUX, iGPU only";
130 return "No MUX, dGPU only";
132 return "MUXed between iGPU and dGPU";
138 static void intel_dsm_platform_mux_info(void)
140 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
141 struct acpi_object_list input;
142 union acpi_object params[4];
143 union acpi_object *pkg;
147 input.pointer = params;
148 params[0].type = ACPI_TYPE_BUFFER;
149 params[0].buffer.length = sizeof(intel_dsm_guid);
150 params[0].buffer.pointer = (char *)intel_dsm_guid;
151 params[1].type = ACPI_TYPE_INTEGER;
152 params[1].integer.value = INTEL_DSM_REVISION_ID;
153 params[2].type = ACPI_TYPE_INTEGER;
154 params[2].integer.value = INTEL_DSM_FN_PLATFORM_MUX_INFO;
155 params[3].type = ACPI_TYPE_PACKAGE;
156 params[3].package.count = 0;
157 params[3].package.elements = NULL;
159 ret = acpi_evaluate_object(intel_dsm_priv.dhandle, "_DSM", &input,
162 DRM_DEBUG_DRIVER("failed to evaluate _DSM: %d\n", ret);
166 pkg = (union acpi_object *)output.pointer;
168 if (pkg->type == ACPI_TYPE_PACKAGE) {
169 union acpi_object *connector_count = &pkg->package.elements[0];
170 DRM_DEBUG_DRIVER("MUX info connectors: %lld\n",
171 (unsigned long long)connector_count->integer.value);
172 for (i = 1; i < pkg->package.count; i++) {
173 union acpi_object *obj = &pkg->package.elements[i];
174 union acpi_object *connector_id =
175 &obj->package.elements[0];
176 union acpi_object *info = &obj->package.elements[1];
177 DRM_DEBUG_DRIVER("Connector id: 0x%016llx\n",
178 (unsigned long long)connector_id->integer.value);
179 DRM_DEBUG_DRIVER(" port id: %s\n",
180 intel_dsm_port_name(info->buffer.pointer[0]));
181 DRM_DEBUG_DRIVER(" display mux info: %s\n",
182 intel_dsm_mux_type(info->buffer.pointer[1]));
183 DRM_DEBUG_DRIVER(" aux/dc mux info: %s\n",
184 intel_dsm_mux_type(info->buffer.pointer[2]));
185 DRM_DEBUG_DRIVER(" hpd mux info: %s\n",
186 intel_dsm_mux_type(info->buffer.pointer[3]));
191 kfree(output.pointer);
194 static bool intel_dsm_pci_probe(struct pci_dev *pdev)
199 dhandle = ACPI_HANDLE(&pdev->dev);
203 if (!acpi_has_method(dhandle, "_DSM")) {
204 DRM_DEBUG_KMS("no _DSM method for intel device\n");
208 ret = intel_dsm(dhandle, INTEL_DSM_FN_SUPPORTED_FUNCTIONS);
210 DRM_DEBUG_KMS("failed to get supported _DSM functions\n");
214 intel_dsm_priv.dhandle = dhandle;
216 intel_dsm_platform_mux_info();
220 static bool intel_dsm_detect(void)
222 char acpi_method_name[255] = { 0 };
223 struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
224 struct pci_dev *pdev = NULL;
225 bool has_dsm = false;
228 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
230 has_dsm |= intel_dsm_pci_probe(pdev);
233 if (vga_count == 2 && has_dsm) {
234 acpi_get_name(intel_dsm_priv.dhandle, ACPI_FULL_PATHNAME, &buffer);
235 DRM_DEBUG_DRIVER("VGA switcheroo: detected DSM switching method %s handle\n",
243 void intel_register_dsm_handler(void)
245 if (!intel_dsm_detect())
249 void intel_unregister_dsm_handler(void)