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 modalias_show(struct device *dev, 61 struct device_attribute *attr, char *buf) 62 { 63 struct of_device *ofdev = to_of_device(dev); 64 ssize_t len = 0; 65 66 len = of_device_get_modalias(ofdev, buf, PAGE_SIZE - 2); 67 buf[len] = '\n'; 68 buf[len+1] = 0; 69 return len+1; 70 } 71 72 struct device_attribute of_platform_device_attrs[] = { 73 __ATTR_RO(devspec), 74 __ATTR_RO(modalias), 75 __ATTR_NULL 76 }; 77 78 /** 79 * of_release_dev - free an of device structure when all users of it are finished. 80 * @dev: device that's been disconnected 81 * 82 * Will be called only by the device core when all users of this of device are 83 * done. 84 */ 85 void of_release_dev(struct device *dev) 86 { 87 struct of_device *ofdev; 88 89 ofdev = to_of_device(dev); 90 of_node_put(ofdev->node); 91 kfree(ofdev); 92 } 93 EXPORT_SYMBOL(of_release_dev); 94 95 int of_device_register(struct of_device *ofdev) 96 { 97 BUG_ON(ofdev->node == NULL); 98 return device_register(&ofdev->dev); 99 } 100 EXPORT_SYMBOL(of_device_register); 101 102 void of_device_unregister(struct of_device *ofdev) 103 { 104 device_unregister(&ofdev->dev); 105 } 106 EXPORT_SYMBOL(of_device_unregister); 107 108 ssize_t of_device_get_modalias(struct of_device *ofdev, 109 char *str, ssize_t len) 110 { 111 const char *compat; 112 int cplen, i; 113 ssize_t tsize, csize, repend; 114 115 /* Name & Type */ 116 csize = snprintf(str, len, "of:N%sT%s", 117 ofdev->node->name, ofdev->node->type); 118 119 /* Get compatible property if any */ 120 compat = of_get_property(ofdev->node, "compatible", &cplen); 121 if (!compat) 122 return csize; 123 124 /* Find true end (we tolerate multiple \0 at the end */ 125 for (i = (cplen - 1); i >= 0 && !compat[i]; i--) 126 cplen--; 127 if (!cplen) 128 return csize; 129 cplen++; 130 131 /* Check space (need cplen+1 chars including final \0) */ 132 tsize = csize + cplen; 133 repend = tsize; 134 135 if (csize >= len) /* @ the limit, all is already filled */ 136 return tsize; 137 138 if (tsize >= len) { /* limit compat list */ 139 cplen = len - csize - 1; 140 repend = len; 141 } 142 143 /* Copy and do char replacement */ 144 memcpy(&str[csize + 1], compat, cplen); 145 for (i = csize; i < repend; i++) { 146 char c = str[i]; 147 if (c == '\0') 148 str[i] = 'C'; 149 else if (c == ' ') 150 str[i] = '_'; 151 } 152 153 return tsize; 154 } 155