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 of_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 (!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 of_device *of_dev_get(struct of_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_of_device(tmp); 38 else 39 return NULL; 40 } 41 EXPORT_SYMBOL(of_dev_get); 42 43 void of_dev_put(struct of_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 of_device *ofdev; 54 55 ofdev = to_of_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 of_device *ofdev; 63 64 ofdev = to_of_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 struct of_device *ofdev = to_of_device(dev); 72 ssize_t len = 0; 73 74 len = of_device_get_modalias(ofdev, buf, PAGE_SIZE - 2); 75 buf[len] = '\n'; 76 buf[len+1] = 0; 77 return len+1; 78 } 79 80 struct device_attribute of_platform_device_attrs[] = { 81 __ATTR_RO(devspec), 82 __ATTR_RO(name), 83 __ATTR_RO(modalias), 84 __ATTR_NULL 85 }; 86 87 /** 88 * of_release_dev - free an of device structure when all users of it are finished. 89 * @dev: device that's been disconnected 90 * 91 * Will be called only by the device core when all users of this of device are 92 * done. 93 */ 94 void of_release_dev(struct device *dev) 95 { 96 struct of_device *ofdev; 97 98 ofdev = to_of_device(dev); 99 of_node_put(ofdev->dev.of_node); 100 kfree(ofdev); 101 } 102 EXPORT_SYMBOL(of_release_dev); 103 104 int of_device_register(struct of_device *ofdev) 105 { 106 BUG_ON(ofdev->dev.of_node == NULL); 107 108 device_initialize(&ofdev->dev); 109 110 /* device_add will assume that this device is on the same node as 111 * the parent. If there is no parent defined, set the node 112 * explicitly */ 113 if (!ofdev->dev.parent) 114 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node)); 115 116 return device_add(&ofdev->dev); 117 } 118 EXPORT_SYMBOL(of_device_register); 119 120 void of_device_unregister(struct of_device *ofdev) 121 { 122 device_unregister(&ofdev->dev); 123 } 124 EXPORT_SYMBOL(of_device_unregister); 125 126 ssize_t of_device_get_modalias(struct of_device *ofdev, 127 char *str, ssize_t len) 128 { 129 const char *compat; 130 int cplen, i; 131 ssize_t tsize, csize, repend; 132 133 /* Name & Type */ 134 csize = snprintf(str, len, "of:N%sT%s", ofdev->dev.of_node->name, 135 ofdev->dev.of_node->type); 136 137 /* Get compatible property if any */ 138 compat = of_get_property(ofdev->dev.of_node, "compatible", &cplen); 139 if (!compat) 140 return csize; 141 142 /* Find true end (we tolerate multiple \0 at the end */ 143 for (i = (cplen - 1); i >= 0 && !compat[i]; i--) 144 cplen--; 145 if (!cplen) 146 return csize; 147 cplen++; 148 149 /* Check space (need cplen+1 chars including final \0) */ 150 tsize = csize + cplen; 151 repend = tsize; 152 153 if (csize >= len) /* @ the limit, all is already filled */ 154 return tsize; 155 156 if (tsize >= len) { /* limit compat list */ 157 cplen = len - csize - 1; 158 repend = len; 159 } 160 161 /* Copy and do char replacement */ 162 memcpy(&str[csize + 1], compat, cplen); 163 for (i = csize; i < repend; i++) { 164 char c = str[i]; 165 if (c == '\0') 166 str[i] = 'C'; 167 else if (c == ' ') 168 str[i] = '_'; 169 } 170 171 return tsize; 172 } 173