1 #include <linux/string.h> 2 #include <linux/kernel.h> 3 #include <linux/of.h> 4 #include <linux/of_device.h> 5 #include <linux/init.h> 6 #include <linux/module.h> 7 #include <linux/mod_devicetable.h> 8 #include <linux/slab.h> 9 10 #include <asm/errno.h> 11 12 /** 13 * of_match_device - Tell if a struct device matches an of_device_id list 14 * @ids: array of of device match structures to search in 15 * @dev: the of device structure to match against 16 * 17 * Used by a driver to check whether an platform_device present in the 18 * system is in its list of supported devices. 19 */ 20 const struct of_device_id *of_match_device(const struct of_device_id *matches, 21 const struct device *dev) 22 { 23 if ((!matches) || (!dev->of_node)) 24 return NULL; 25 return of_match_node(matches, dev->of_node); 26 } 27 EXPORT_SYMBOL(of_match_device); 28 29 struct platform_device *of_dev_get(struct platform_device *dev) 30 { 31 struct device *tmp; 32 33 if (!dev) 34 return NULL; 35 tmp = get_device(&dev->dev); 36 if (tmp) 37 return to_platform_device(tmp); 38 else 39 return NULL; 40 } 41 EXPORT_SYMBOL(of_dev_get); 42 43 void of_dev_put(struct platform_device *dev) 44 { 45 if (dev) 46 put_device(&dev->dev); 47 } 48 EXPORT_SYMBOL(of_dev_put); 49 50 static ssize_t devspec_show(struct device *dev, 51 struct device_attribute *attr, char *buf) 52 { 53 struct platform_device *ofdev; 54 55 ofdev = to_platform_device(dev); 56 return sprintf(buf, "%s\n", ofdev->dev.of_node->full_name); 57 } 58 59 static ssize_t name_show(struct device *dev, 60 struct device_attribute *attr, char *buf) 61 { 62 struct platform_device *ofdev; 63 64 ofdev = to_platform_device(dev); 65 return sprintf(buf, "%s\n", ofdev->dev.of_node->name); 66 } 67 68 static ssize_t modalias_show(struct device *dev, 69 struct device_attribute *attr, char *buf) 70 { 71 ssize_t len = of_device_get_modalias(dev, buf, PAGE_SIZE - 2); 72 buf[len] = '\n'; 73 buf[len+1] = 0; 74 return len+1; 75 } 76 77 struct device_attribute of_platform_device_attrs[] = { 78 __ATTR_RO(devspec), 79 __ATTR_RO(name), 80 __ATTR_RO(modalias), 81 __ATTR_NULL 82 }; 83 84 /** 85 * of_release_dev - free an of device structure when all users of it are finished. 86 * @dev: device that's been disconnected 87 * 88 * Will be called only by the device core when all users of this of device are 89 * done. 90 */ 91 void of_release_dev(struct device *dev) 92 { 93 struct platform_device *ofdev; 94 95 ofdev = to_platform_device(dev); 96 of_node_put(ofdev->dev.of_node); 97 kfree(ofdev); 98 } 99 EXPORT_SYMBOL(of_release_dev); 100 101 int of_device_register(struct platform_device *ofdev) 102 { 103 BUG_ON(ofdev->dev.of_node == NULL); 104 105 device_initialize(&ofdev->dev); 106 107 /* name and id have to be set so that the platform bus doesn't get 108 * confused on matching */ 109 ofdev->name = dev_name(&ofdev->dev); 110 ofdev->id = -1; 111 112 /* device_add will assume that this device is on the same node as 113 * the parent. If there is no parent defined, set the node 114 * explicitly */ 115 if (!ofdev->dev.parent) 116 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node)); 117 118 return device_add(&ofdev->dev); 119 } 120 EXPORT_SYMBOL(of_device_register); 121 122 void of_device_unregister(struct platform_device *ofdev) 123 { 124 device_unregister(&ofdev->dev); 125 } 126 EXPORT_SYMBOL(of_device_unregister); 127 128 ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len) 129 { 130 const char *compat; 131 int cplen, i; 132 ssize_t tsize, csize, repend; 133 134 /* Name & Type */ 135 csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name, 136 dev->of_node->type); 137 138 /* Get compatible property if any */ 139 compat = of_get_property(dev->of_node, "compatible", &cplen); 140 if (!compat) 141 return csize; 142 143 /* Find true end (we tolerate multiple \0 at the end */ 144 for (i = (cplen - 1); i >= 0 && !compat[i]; i--) 145 cplen--; 146 if (!cplen) 147 return csize; 148 cplen++; 149 150 /* Check space (need cplen+1 chars including final \0) */ 151 tsize = csize + cplen; 152 repend = tsize; 153 154 if (csize >= len) /* @ the limit, all is already filled */ 155 return tsize; 156 157 if (tsize >= len) { /* limit compat list */ 158 cplen = len - csize - 1; 159 repend = len; 160 } 161 162 /* Copy and do char replacement */ 163 memcpy(&str[csize + 1], compat, cplen); 164 for (i = csize; i < repend; i++) { 165 char c = str[i]; 166 if (c == '\0') 167 str[i] = 'C'; 168 else if (c == ' ') 169 str[i] = '_'; 170 } 171 172 return tsize; 173 } 174 175 /** 176 * of_device_uevent - Display OF related uevent information 177 */ 178 int of_device_uevent(struct device *dev, struct kobj_uevent_env *env) 179 { 180 const char *compat; 181 int seen = 0, cplen, sl; 182 183 if ((!dev) || (!dev->of_node)) 184 return -ENODEV; 185 186 if (add_uevent_var(env, "OF_NAME=%s", dev->of_node->name)) 187 return -ENOMEM; 188 189 if (add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type)) 190 return -ENOMEM; 191 192 /* Since the compatible field can contain pretty much anything 193 * it's not really legal to split it out with commas. We split it 194 * up using a number of environment variables instead. */ 195 196 compat = of_get_property(dev->of_node, "compatible", &cplen); 197 while (compat && *compat && cplen > 0) { 198 if (add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat)) 199 return -ENOMEM; 200 201 sl = strlen(compat) + 1; 202 compat += sl; 203 cplen -= sl; 204 seen++; 205 } 206 207 if (add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen)) 208 return -ENOMEM; 209 210 /* modalias is trickier, we add it in 2 steps */ 211 if (add_uevent_var(env, "MODALIAS=")) 212 return -ENOMEM; 213 214 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1], 215 sizeof(env->buf) - env->buflen); 216 if (sl >= (sizeof(env->buf) - env->buflen)) 217 return -ENOMEM; 218 env->buflen += sl; 219 220 return 0; 221 } 222