1 /************************************************************************** 2 * 3 * Copyright 2009 VMware, Inc., Palo Alto, CA., USA 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 24 * USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 /* 28 * Thanks to krh and jcristau for the tips on 29 * going from fd to pci id via fstat and udev. 30 */ 31 32 #include <errno.h> 33 #include <stdio.h> 34 #include <stdlib.h> 35 #include <xf86drm.h> 36 #include <string.h> 37 #include <unistd.h> 38 #include <sys/stat.h> 39 #include <sys/types.h> 40 #ifdef MAJOR_IN_MKDEV 41 #include <sys/mkdev.h> 42 #endif 43 #ifdef MAJOR_IN_SYSMACROS 44 #include <sys/sysmacros.h> 45 #endif 46 47 #include "libdrm_macros.h" 48 #include "internal.h" 49 50 #define PATH_SIZE 512 51 52 static int 53 linux_name_from_sysfs(int fd, char **out) 54 { 55 char path[PATH_SIZE+1] = ""; /* initialize to please valgrind */ 56 char link[PATH_SIZE+1] = ""; 57 struct stat buffer; 58 unsigned maj, min; 59 char* slash_name; 60 int ret; 61 62 /* 63 * Inside the sysfs directory for the device there is a symlink 64 * to the directory representing the driver module, that path 65 * happens to hold the name of the driver. 66 * 67 * So lets get the symlink for the drm device. Then read the link 68 * and filter out the last directory which happens to be the name 69 * of the driver, which we can use to load the correct interface. 70 * 71 * Thanks to Ray Strode of Plymouth for the code. 72 */ 73 74 ret = fstat(fd, &buffer); 75 if (ret) 76 return -EINVAL; 77 78 if (!S_ISCHR(buffer.st_mode)) 79 return -EINVAL; 80 81 maj = major(buffer.st_rdev); 82 min = minor(buffer.st_rdev); 83 84 snprintf(path, PATH_SIZE, "/sys/dev/char/%d:%d/device/driver", maj, min); 85 86 if (readlink(path, link, PATH_SIZE) < 0) 87 return -EINVAL; 88 89 /* link looks something like this: ../../../bus/pci/drivers/intel */ 90 slash_name = strrchr(link, '/'); 91 if (!slash_name) 92 return -EINVAL; 93 94 /* copy name and at the same time remove the slash */ 95 *out = strdup(slash_name + 1); 96 return 0; 97 } 98 99 static int 100 linux_from_sysfs(int fd, struct kms_driver **out) 101 { 102 char *name; 103 int ret; 104 105 ret = linux_name_from_sysfs(fd, &name); 106 if (ret) 107 return ret; 108 109 #if HAVE_INTEL 110 if (!strcmp(name, "intel")) 111 ret = intel_create(fd, out); 112 else 113 #endif 114 #if HAVE_VMWGFX 115 if (!strcmp(name, "vmwgfx")) 116 ret = vmwgfx_create(fd, out); 117 else 118 #endif 119 #if HAVE_NOUVEAU 120 if (!strcmp(name, "nouveau")) 121 ret = nouveau_create(fd, out); 122 else 123 #endif 124 #if HAVE_RADEON 125 if (!strcmp(name, "radeon")) 126 ret = radeon_create(fd, out); 127 else 128 #endif 129 #if HAVE_EXYNOS 130 if (!strcmp(name, "exynos")) 131 ret = exynos_create(fd, out); 132 else 133 #endif 134 ret = -ENOSYS; 135 136 free(name); 137 return ret; 138 } 139 140 drm_private int 141 linux_create(int fd, struct kms_driver **out) 142 { 143 if (!dumb_create(fd, out)) 144 return 0; 145 146 return linux_from_sysfs(fd, out); 147 } 148
