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>
13 #define INTEL_DSM_REVISION_ID 1 /* For Calpella anyway... */
15 #define INTEL_DSM_FN_SUPPORTED_FUNCTIONS 0 /* No args */
16 #define INTEL_DSM_FN_PLATFORM_MUX_INFO 1 /* No args */
18 static struct intel_dsm_priv {
22 static const u8 intel_dsm_guid[] = {
23 0xd3, 0x73, 0xd8, 0x7e,
27 0x0f, 0x13, 0x17, 0xb0, 0x1c, 0x2c
30 static int intel_dsm(acpi_handle handle, int func, int arg)
32 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
33 struct acpi_object_list input;
34 union acpi_object params[4];
35 union acpi_object *obj;
40 input.pointer = params;
41 params[0].type = ACPI_TYPE_BUFFER;
42 params[0].buffer.length = sizeof(intel_dsm_guid);
43 params[0].buffer.pointer = (char *)intel_dsm_guid;
44 params[1].type = ACPI_TYPE_INTEGER;
45 params[1].integer.value = INTEL_DSM_REVISION_ID;
46 params[2].type = ACPI_TYPE_INTEGER;
47 params[2].integer.value = func;
48 params[3].type = ACPI_TYPE_INTEGER;
49 params[3].integer.value = arg;
51 ret = acpi_evaluate_object(handle, "_DSM", &input, &output);
53 DRM_DEBUG_DRIVER("failed to evaluate _DSM: %d\n", ret);
57 obj = (union acpi_object *)output.pointer;
61 case ACPI_TYPE_INTEGER:
62 result = obj->integer.value;
65 case ACPI_TYPE_BUFFER:
66 if (obj->buffer.length == 4) {
67 result = (obj->buffer.pointer[0] |
68 (obj->buffer.pointer[1] << 8) |
69 (obj->buffer.pointer[2] << 16) |
70 (obj->buffer.pointer[3] << 24));
77 if (result == 0x80000002)
80 kfree(output.pointer);
84 static char *intel_dsm_port_name(u8 id)
102 return "DisplayPort_A";
104 return "DisplayPort_B";
106 return "DisplayPort_C";
108 return "DisplayPort_D";
120 static char *intel_dsm_mux_type(u8 type)
126 return "No MUX, iGPU only";
128 return "No MUX, dGPU only";
130 return "MUXed between iGPU and dGPU";
136 static void intel_dsm_platform_mux_info(void)
138 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
139 struct acpi_object_list input;
140 union acpi_object params[4];
141 union acpi_object *pkg;
145 input.pointer = params;
146 params[0].type = ACPI_TYPE_BUFFER;
147 params[0].buffer.length = sizeof(intel_dsm_guid);
148 params[0].buffer.pointer = (char *)intel_dsm_guid;
149 params[1].type = ACPI_TYPE_INTEGER;
150 params[1].integer.value = INTEL_DSM_REVISION_ID;
151 params[2].type = ACPI_TYPE_INTEGER;
152 params[2].integer.value = INTEL_DSM_FN_PLATFORM_MUX_INFO;
153 params[3].type = ACPI_TYPE_INTEGER;
154 params[3].integer.value = 0;
156 ret = acpi_evaluate_object(intel_dsm_priv.dhandle, "_DSM", &input,
159 DRM_DEBUG_DRIVER("failed to evaluate _DSM: %d\n", ret);
163 pkg = (union acpi_object *)output.pointer;
165 if (pkg->type == ACPI_TYPE_PACKAGE) {
166 union acpi_object *connector_count = &pkg->package.elements[0];
167 DRM_DEBUG_DRIVER("MUX info connectors: %lld\n",
168 (unsigned long long)connector_count->integer.value);
169 for (i = 1; i < pkg->package.count; i++) {
170 union acpi_object *obj = &pkg->package.elements[i];
171 union acpi_object *connector_id =
172 &obj->package.elements[0];
173 union acpi_object *info = &obj->package.elements[1];
174 DRM_DEBUG_DRIVER("Connector id: 0x%016llx\n",
175 (unsigned long long)connector_id->integer.value);
176 DRM_DEBUG_DRIVER(" port id: %s\n",
177 intel_dsm_port_name(info->buffer.pointer[0]));
178 DRM_DEBUG_DRIVER(" display mux info: %s\n",
179 intel_dsm_mux_type(info->buffer.pointer[1]));
180 DRM_DEBUG_DRIVER(" aux/dc mux info: %s\n",
181 intel_dsm_mux_type(info->buffer.pointer[2]));
182 DRM_DEBUG_DRIVER(" hpd mux info: %s\n",
183 intel_dsm_mux_type(info->buffer.pointer[3]));
186 DRM_ERROR("MUX INFO call failed\n");
190 kfree(output.pointer);
193 static bool intel_dsm_pci_probe(struct pci_dev *pdev)
195 acpi_handle dhandle, intel_handle;
199 dhandle = DEVICE_ACPI_HANDLE(&pdev->dev);
203 status = acpi_get_handle(dhandle, "_DSM", &intel_handle);
204 if (ACPI_FAILURE(status)) {
205 DRM_DEBUG_KMS("no _DSM method for intel device\n");
209 ret = intel_dsm(dhandle, INTEL_DSM_FN_SUPPORTED_FUNCTIONS, 0);
211 DRM_DEBUG_KMS("failed to get supported _DSM functions\n");
215 intel_dsm_priv.dhandle = dhandle;
217 intel_dsm_platform_mux_info();
221 static bool intel_dsm_detect(void)
223 char acpi_method_name[255] = { 0 };
224 struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
225 struct pci_dev *pdev = NULL;
226 bool has_dsm = false;
229 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
231 has_dsm |= intel_dsm_pci_probe(pdev);
234 if (vga_count == 2 && has_dsm) {
235 acpi_get_name(intel_dsm_priv.dhandle, ACPI_FULL_PATHNAME, &buffer);
236 DRM_DEBUG_DRIVER("VGA switcheroo: detected DSM switching method %s handle\n",
244 void intel_register_dsm_handler(void)
246 if (!intel_dsm_detect())
250 void intel_unregister_dsm_handler(void)