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 an of_device structure has a matching 14 * of_match structure 15 * @ids: array of of device match structures to search in 16 * @dev: the of device structure to match against 17 * 18 * Used by a driver to check whether an of_device present in the 19 * system is in its list of supported devices. 20 */ 21 const struct of_device_id *of_match_device(const struct of_device_id *matches, 22 const struct of_device *dev) 23 { 24 if (!dev->node) 25 return NULL; 26 return of_match_node(matches, dev->node); 27 } 28 EXPORT_SYMBOL(of_match_device); 29 30 struct of_device *of_dev_get(struct of_device *dev) 31 { 32 struct device *tmp; 33 34 if (!dev) 35 return NULL; 36 tmp = get_device(&dev->dev); 37 if (tmp) 38 return to_of_device(tmp); 39 else 40 return NULL; 41 } 42 EXPORT_SYMBOL(of_dev_get); 43 44 void of_dev_put(struct of_device *dev) 45 { 46 if (dev) 47 put_device(&dev->dev); 48 } 49 EXPORT_SYMBOL(of_dev_put); 50 51 static ssize_t devspec_show(struct device *dev, 52 struct device_attribute *attr, char *buf) 53 { 54 struct of_device *ofdev; 55 56 ofdev = to_of_device(dev); 57 return sprintf(buf, "%s\n", ofdev->node->full_name); 58 } 59 60 static ssize_t name_show(struct device *dev, 61 struct device_attribute *attr, char *buf) 62 { 63 struct of_device *ofdev; 64 65 ofdev = to_of_device(dev); 66 return sprintf(buf, "%s\n", ofdev->node->name); 67 } 68 69 static ssize_t modalias_show(struct device *dev, 70 struct device_attribute *attr, char *buf) 71 { 72 struct of_device *ofdev = to_of_device(dev); 73 ssize_t len = 0; 74 75 len = of_device_get_modalias(ofdev, buf, PAGE_SIZE - 2); 76 buf[len] = '\n'; 77 buf[len+1] = 0; 78 return len+1; 79 } 80 81 struct device_attribute of_platform_device_attrs[] = { 82 __ATTR_RO(devspec), 83 __ATTR_RO(name), 84 __ATTR_RO(modalias), 85 __ATTR_NULL 86 }; 87 88 /** 89 * of_release_dev - free an of device structure when all users of it are finished. 90 * @dev: device that's been disconnected 91 * 92 * Will be called only by the device core when all users of this of device are 93 * done. 94 */ 95 void of_release_dev(struct device *dev) 96 { 97 struct of_device *ofdev; 98 99 ofdev = to_of_device(dev); 100 of_node_put(ofdev->node); 101 kfree(ofdev); 102 } 103 EXPORT_SYMBOL(of_release_dev); 104 105 int of_device_register(struct of_device *ofdev) 106 { 107 BUG_ON(ofdev->node == NULL); 108 return device_register(&ofdev->dev); 109 } 110 EXPORT_SYMBOL(of_device_register); 111 112 void of_device_unregister(struct of_device *ofdev) 113 { 114 device_unregister(&ofdev->dev); 115 } 116 EXPORT_SYMBOL(of_device_unregister); 117 118 ssize_t of_device_get_modalias(struct of_device *ofdev, 119 char *str, ssize_t len) 120 { 121 const char *compat; 122 int cplen, i; 123 ssize_t tsize, csize, repend; 124 125 /* Name & Type */ 126 csize = snprintf(str, len, "of:N%sT%s", 127 ofdev->node->name, ofdev->node->type); 128 129 /* Get compatible property if any */ 130 compat = of_get_property(ofdev->node, "compatible", &cplen); 131 if (!compat) 132 return csize; 133 134 /* Find true end (we tolerate multiple \0 at the end */ 135 for (i = (cplen - 1); i >= 0 && !compat[i]; i--) 136 cplen--; 137 if (!cplen) 138 return csize; 139 cplen++; 140 141 /* Check space (need cplen+1 chars including final \0) */ 142 tsize = csize + cplen; 143 repend = tsize; 144 145 if (csize >= len) /* @ the limit, all is already filled */ 146 return tsize; 147 148 if (tsize >= len) { /* limit compat list */ 149 cplen = len - csize - 1; 150 repend = len; 151 } 152 153 /* Copy and do char replacement */ 154 memcpy(&str[csize + 1], compat, cplen); 155 for (i = csize; i < repend; i++) { 156 char c = str[i]; 157 if (c == '\0') 158 str[i] = 'C'; 159 else if (c == ' ') 160 str[i] = '_'; 161 } 162 163 return tsize; 164 } 165