1 /* 2 * Copyright (c) 2010 Red Hat Inc. 3 * Author : Dave Airlie <airlied@redhat.com> 4 * 5 * Licensed under GPLv2 6 * 7 * ATPX support for both Intel/ATI 8 */ 9 #include <linux/vga_switcheroo.h> 10 #include <linux/slab.h> 11 #include <acpi/acpi.h> 12 #include <acpi/acpi_bus.h> 13 #include <linux/pci.h> 14 15 #define ATPX_VERSION 0 16 #define ATPX_GPU_PWR 2 17 #define ATPX_MUX_SELECT 3 18 #define ATPX_I2C_MUX_SELECT 4 19 #define ATPX_SWITCH_START 5 20 #define ATPX_SWITCH_END 6 21 22 #define ATPX_INTEGRATED 0 23 #define ATPX_DISCRETE 1 24 25 #define ATPX_MUX_IGD 0 26 #define ATPX_MUX_DISCRETE 1 27 28 static struct radeon_atpx_priv { 29 bool atpx_detected; 30 /* handle for device - and atpx */ 31 acpi_handle dhandle; 32 acpi_handle atpx_handle; 33 } radeon_atpx_priv; 34 35 static int radeon_atpx_get_version(acpi_handle handle) 36 { 37 acpi_status status; 38 union acpi_object atpx_arg_elements[2], *obj; 39 struct acpi_object_list atpx_arg; 40 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 41 42 atpx_arg.count = 2; 43 atpx_arg.pointer = &atpx_arg_elements[0]; 44 45 atpx_arg_elements[0].type = ACPI_TYPE_INTEGER; 46 atpx_arg_elements[0].integer.value = ATPX_VERSION; 47 48 atpx_arg_elements[1].type = ACPI_TYPE_INTEGER; 49 atpx_arg_elements[1].integer.value = ATPX_VERSION; 50 51 status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer); 52 if (ACPI_FAILURE(status)) { 53 printk("%s: failed to call ATPX: %s\n", __func__, acpi_format_exception(status)); 54 return -ENOSYS; 55 } 56 obj = (union acpi_object *)buffer.pointer; 57 if (obj && (obj->type == ACPI_TYPE_BUFFER)) 58 printk(KERN_INFO "radeon atpx: version is %d\n", *((u8 *)(obj->buffer.pointer) + 2)); 59 kfree(buffer.pointer); 60 return 0; 61 } 62 63 static int radeon_atpx_execute(acpi_handle handle, int cmd_id, u16 value) 64 { 65 acpi_status status; 66 union acpi_object atpx_arg_elements[2]; 67 struct acpi_object_list atpx_arg; 68 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 69 uint8_t buf[4] = {0}; 70 71 if (!handle) 72 return -EINVAL; 73 74 atpx_arg.count = 2; 75 atpx_arg.pointer = &atpx_arg_elements[0]; 76 77 atpx_arg_elements[0].type = ACPI_TYPE_INTEGER; 78 atpx_arg_elements[0].integer.value = cmd_id; 79 80 buf[2] = value & 0xff; 81 buf[3] = (value >> 8) & 0xff; 82 83 atpx_arg_elements[1].type = ACPI_TYPE_BUFFER; 84 atpx_arg_elements[1].buffer.length = 4; 85 atpx_arg_elements[1].buffer.pointer = buf; 86 87 status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer); 88 if (ACPI_FAILURE(status)) { 89 printk("%s: failed to call ATPX: %s\n", __func__, acpi_format_exception(status)); 90 return -ENOSYS; 91 } 92 kfree(buffer.pointer); 93 94 return 0; 95 } 96 97 static int radeon_atpx_set_discrete_state(acpi_handle handle, int state) 98 { 99 return radeon_atpx_execute(handle, ATPX_GPU_PWR, state); 100 } 101 102 static int radeon_atpx_switch_mux(acpi_handle handle, int mux_id) 103 { 104 return radeon_atpx_execute(handle, ATPX_MUX_SELECT, mux_id); 105 } 106 107 static int radeon_atpx_switch_i2c_mux(acpi_handle handle, int mux_id) 108 { 109 return radeon_atpx_execute(handle, ATPX_I2C_MUX_SELECT, mux_id); 110 } 111 112 static int radeon_atpx_switch_start(acpi_handle handle, int gpu_id) 113 { 114 return radeon_atpx_execute(handle, ATPX_SWITCH_START, gpu_id); 115 } 116 117 static int radeon_atpx_switch_end(acpi_handle handle, int gpu_id) 118 { 119 return radeon_atpx_execute(handle, ATPX_SWITCH_END, gpu_id); 120 } 121 122 static int radeon_atpx_switchto(enum vga_switcheroo_client_id id) 123 { 124 int gpu_id; 125 126 if (id == VGA_SWITCHEROO_IGD) 127 gpu_id = ATPX_INTEGRATED; 128 else 129 gpu_id = ATPX_DISCRETE; 130 131 radeon_atpx_switch_start(radeon_atpx_priv.atpx_handle, gpu_id); 132 radeon_atpx_switch_mux(radeon_atpx_priv.atpx_handle, gpu_id); 133 radeon_atpx_switch_i2c_mux(radeon_atpx_priv.atpx_handle, gpu_id); 134 radeon_atpx_switch_end(radeon_atpx_priv.atpx_handle, gpu_id); 135 136 return 0; 137 } 138 139 static int radeon_atpx_power_state(enum vga_switcheroo_client_id id, 140 enum vga_switcheroo_state state) 141 { 142 /* on w500 ACPI can't change intel gpu state */ 143 if (id == VGA_SWITCHEROO_IGD) 144 return 0; 145 146 radeon_atpx_set_discrete_state(radeon_atpx_priv.atpx_handle, state); 147 return 0; 148 } 149 150 static bool radeon_atpx_pci_probe_handle(struct pci_dev *pdev) 151 { 152 acpi_handle dhandle, atpx_handle; 153 acpi_status status; 154 155 dhandle = DEVICE_ACPI_HANDLE(&pdev->dev); 156 if (!dhandle) 157 return false; 158 159 status = acpi_get_handle(dhandle, "ATPX", &atpx_handle); 160 if (ACPI_FAILURE(status)) 161 return false; 162 163 radeon_atpx_priv.dhandle = dhandle; 164 radeon_atpx_priv.atpx_handle = atpx_handle; 165 return true; 166 } 167 168 static int radeon_atpx_init(void) 169 { 170 /* set up the ATPX handle */ 171 172 radeon_atpx_get_version(radeon_atpx_priv.atpx_handle); 173 return 0; 174 } 175 176 static int radeon_atpx_get_client_id(struct pci_dev *pdev) 177 { 178 if (radeon_atpx_priv.dhandle == DEVICE_ACPI_HANDLE(&pdev->dev)) 179 return VGA_SWITCHEROO_IGD; 180 else 181 return VGA_SWITCHEROO_DIS; 182 } 183 184 static struct vga_switcheroo_handler radeon_atpx_handler = { 185 .switchto = radeon_atpx_switchto, 186 .power_state = radeon_atpx_power_state, 187 .init = radeon_atpx_init, 188 .get_client_id = radeon_atpx_get_client_id, 189 }; 190 191 static bool radeon_atpx_detect(void) 192 { 193 char acpi_method_name[255] = { 0 }; 194 struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name}; 195 struct pci_dev *pdev = NULL; 196 bool has_atpx = false; 197 int vga_count = 0; 198 199 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) { 200 vga_count++; 201 202 has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true); 203 } 204 205 if (has_atpx && vga_count == 2) { 206 acpi_get_name(radeon_atpx_priv.atpx_handle, ACPI_FULL_PATHNAME, &buffer); 207 printk(KERN_INFO "VGA switcheroo: detected switching method %s handle\n", 208 acpi_method_name); 209 radeon_atpx_priv.atpx_detected = true; 210 return true; 211 } 212 return false; 213 } 214 215 void radeon_register_atpx_handler(void) 216 { 217 bool r; 218 219 /* detect if we have any ATPX + 2 VGA in the system */ 220 r = radeon_atpx_detect(); 221 if (!r) 222 return; 223 224 vga_switcheroo_register_handler(&radeon_atpx_handler); 225 } 226 227 void radeon_unregister_atpx_handler(void) 228 { 229 vga_switcheroo_unregister_handler(); 230 } 231