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 int of_device_add(struct platform_device *ofdev) 85 { 86 BUG_ON(ofdev->dev.of_node == NULL); 87 88 /* name and id have to be set so that the platform bus doesn't get 89 * confused on matching */ 90 ofdev->name = dev_name(&ofdev->dev); 91 ofdev->id = -1; 92 93 /* device_add will assume that this device is on the same node as 94 * the parent. If there is no parent defined, set the node 95 * explicitly */ 96 if (!ofdev->dev.parent) 97 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node)); 98 99 return device_add(&ofdev->dev); 100 } 101 102 int of_device_register(struct platform_device *pdev) 103 { 104 device_initialize(&pdev->dev); 105 return of_device_add(pdev); 106 } 107 EXPORT_SYMBOL(of_device_register); 108 109 void of_device_unregister(struct platform_device *ofdev) 110 { 111 device_unregister(&ofdev->dev); 112 } 113 EXPORT_SYMBOL(of_device_unregister); 114 115 ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len) 116 { 117 const char *compat; 118 int cplen, i; 119 ssize_t tsize, csize, repend; 120 121 /* Name & Type */ 122 csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name, 123 dev->of_node->type); 124 125 /* Get compatible property if any */ 126 compat = of_get_property(dev->of_node, "compatible", &cplen); 127 if (!compat) 128 return csize; 129 130 /* Find true end (we tolerate multiple \0 at the end */ 131 for (i = (cplen - 1); i >= 0 && !compat[i]; i--) 132 cplen--; 133 if (!cplen) 134 return csize; 135 cplen++; 136 137 /* Check space (need cplen+1 chars including final \0) */ 138 tsize = csize + cplen; 139 repend = tsize; 140 141 if (csize >= len) /* @ the limit, all is already filled */ 142 return tsize; 143 144 if (tsize >= len) { /* limit compat list */ 145 cplen = len - csize - 1; 146 repend = len; 147 } 148 149 /* Copy and do char replacement */ 150 memcpy(&str[csize + 1], compat, cplen); 151 for (i = csize; i < repend; i++) { 152 char c = str[i]; 153 if (c == '\0') 154 str[i] = 'C'; 155 else if (c == ' ') 156 str[i] = '_'; 157 } 158 159 return tsize; 160 } 161 162 /** 163 * of_device_uevent - Display OF related uevent information 164 */ 165 int of_device_uevent(struct device *dev, struct kobj_uevent_env *env) 166 { 167 const char *compat; 168 int seen = 0, cplen, sl; 169 170 if ((!dev) || (!dev->of_node)) 171 return -ENODEV; 172 173 if (add_uevent_var(env, "OF_NAME=%s", dev->of_node->name)) 174 return -ENOMEM; 175 176 if (add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type)) 177 return -ENOMEM; 178 179 /* Since the compatible field can contain pretty much anything 180 * it's not really legal to split it out with commas. We split it 181 * up using a number of environment variables instead. */ 182 183 compat = of_get_property(dev->of_node, "compatible", &cplen); 184 while (compat && *compat && cplen > 0) { 185 if (add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat)) 186 return -ENOMEM; 187 188 sl = strlen(compat) + 1; 189 compat += sl; 190 cplen -= sl; 191 seen++; 192 } 193 194 if (add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen)) 195 return -ENOMEM; 196 197 /* modalias is trickier, we add it in 2 steps */ 198 if (add_uevent_var(env, "MODALIAS=")) 199 return -ENOMEM; 200 201 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1], 202 sizeof(env->buf) - env->buflen); 203 if (sl >= (sizeof(env->buf) - env->buflen)) 204 return -ENOMEM; 205 env->buflen += sl; 206 207 return 0; 208 } 209