1 #include <linux/string.h> 2 #include <linux/kernel.h> 3 #include <linux/of.h> 4 #include <linux/of_device.h> 5 #include <linux/of_address.h> 6 #include <linux/of_iommu.h> 7 #include <linux/dma-mapping.h> 8 #include <linux/init.h> 9 #include <linux/module.h> 10 #include <linux/mod_devicetable.h> 11 #include <linux/slab.h> 12 13 #include <asm/errno.h> 14 #include "of_private.h" 15 16 /** 17 * of_match_device - Tell if a struct device matches an of_device_id list 18 * @ids: array of of device match structures to search in 19 * @dev: the of device structure to match against 20 * 21 * Used by a driver to check whether an platform_device present in the 22 * system is in its list of supported devices. 23 */ 24 const struct of_device_id *of_match_device(const struct of_device_id *matches, 25 const struct device *dev) 26 { 27 if ((!matches) || (!dev->of_node)) 28 return NULL; 29 return of_match_node(matches, dev->of_node); 30 } 31 EXPORT_SYMBOL(of_match_device); 32 33 struct platform_device *of_dev_get(struct platform_device *dev) 34 { 35 struct device *tmp; 36 37 if (!dev) 38 return NULL; 39 tmp = get_device(&dev->dev); 40 if (tmp) 41 return to_platform_device(tmp); 42 else 43 return NULL; 44 } 45 EXPORT_SYMBOL(of_dev_get); 46 47 void of_dev_put(struct platform_device *dev) 48 { 49 if (dev) 50 put_device(&dev->dev); 51 } 52 EXPORT_SYMBOL(of_dev_put); 53 54 int of_device_add(struct platform_device *ofdev) 55 { 56 BUG_ON(ofdev->dev.of_node == NULL); 57 58 /* name and id have to be set so that the platform bus doesn't get 59 * confused on matching */ 60 ofdev->name = dev_name(&ofdev->dev); 61 ofdev->id = PLATFORM_DEVID_NONE; 62 63 /* 64 * If this device has not binding numa node in devicetree, that is 65 * of_node_to_nid returns NUMA_NO_NODE. device_add will assume that this 66 * device is on the same node as the parent. 67 */ 68 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node)); 69 70 return device_add(&ofdev->dev); 71 } 72 73 /** 74 * of_dma_configure - Setup DMA configuration 75 * @dev: Device to apply DMA configuration 76 * @np: Pointer to OF node having DMA configuration 77 * 78 * Try to get devices's DMA configuration from DT and update it 79 * accordingly. 80 * 81 * If platform code needs to use its own special DMA configuration, it 82 * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events 83 * to fix up DMA configuration. 84 */ 85 int of_dma_configure(struct device *dev, struct device_node *np) 86 { 87 u64 dma_addr, paddr, size; 88 int ret; 89 bool coherent; 90 unsigned long offset; 91 const struct iommu_ops *iommu; 92 u64 mask; 93 94 /* 95 * Set default coherent_dma_mask to 32 bit. Drivers are expected to 96 * setup the correct supported mask. 97 */ 98 if (!dev->coherent_dma_mask) 99 dev->coherent_dma_mask = DMA_BIT_MASK(32); 100 101 /* 102 * Set it to coherent_dma_mask by default if the architecture 103 * code has not set it. 104 */ 105 if (!dev->dma_mask) 106 dev->dma_mask = &dev->coherent_dma_mask; 107 108 ret = of_dma_get_range(np, &dma_addr, &paddr, &size); 109 if (ret < 0) { 110 dma_addr = offset = 0; 111 size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); 112 } else { 113 offset = PFN_DOWN(paddr - dma_addr); 114 115 /* 116 * Add a work around to treat the size as mask + 1 in case 117 * it is defined in DT as a mask. 118 */ 119 if (size & 1) { 120 dev_warn(dev, "Invalid size 0x%llx for dma-range\n", 121 size); 122 size = size + 1; 123 } 124 125 if (!size) { 126 dev_err(dev, "Adjusted size 0x%llx invalid\n", size); 127 return -EINVAL; 128 } 129 dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset); 130 } 131 132 dev->dma_pfn_offset = offset; 133 134 /* 135 * Limit coherent and dma mask based on size and default mask 136 * set by the driver. 137 */ 138 mask = DMA_BIT_MASK(ilog2(dma_addr + size - 1) + 1); 139 dev->coherent_dma_mask &= mask; 140 *dev->dma_mask &= mask; 141 142 coherent = of_dma_is_coherent(np); 143 dev_dbg(dev, "device is%sdma coherent\n", 144 coherent ? " " : " not "); 145 146 iommu = of_iommu_configure(dev, np); 147 if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER) 148 return -EPROBE_DEFER; 149 150 dev_dbg(dev, "device is%sbehind an iommu\n", 151 iommu ? " " : " not "); 152 153 arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent); 154 155 return 0; 156 } 157 EXPORT_SYMBOL_GPL(of_dma_configure); 158 159 /** 160 * of_dma_deconfigure - Clean up DMA configuration 161 * @dev: Device for which to clean up DMA configuration 162 * 163 * Clean up all configuration performed by of_dma_configure_ops() and free all 164 * resources that have been allocated. 165 */ 166 void of_dma_deconfigure(struct device *dev) 167 { 168 arch_teardown_dma_ops(dev); 169 } 170 171 int of_device_register(struct platform_device *pdev) 172 { 173 device_initialize(&pdev->dev); 174 return of_device_add(pdev); 175 } 176 EXPORT_SYMBOL(of_device_register); 177 178 void of_device_unregister(struct platform_device *ofdev) 179 { 180 device_unregister(&ofdev->dev); 181 } 182 EXPORT_SYMBOL(of_device_unregister); 183 184 const void *of_device_get_match_data(const struct device *dev) 185 { 186 const struct of_device_id *match; 187 188 match = of_match_device(dev->driver->of_match_table, dev); 189 if (!match) 190 return NULL; 191 192 return match->data; 193 } 194 EXPORT_SYMBOL(of_device_get_match_data); 195 196 static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len) 197 { 198 const char *compat; 199 char *c; 200 struct property *p; 201 ssize_t csize; 202 ssize_t tsize; 203 204 if ((!dev) || (!dev->of_node)) 205 return -ENODEV; 206 207 /* Name & Type */ 208 csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name, 209 dev->of_node->type); 210 tsize = csize; 211 len -= csize; 212 if (str) 213 str += csize; 214 215 of_property_for_each_string(dev->of_node, "compatible", p, compat) { 216 csize = strlen(compat) + 1; 217 tsize += csize; 218 if (csize > len) 219 continue; 220 221 csize = snprintf(str, len, "C%s", compat); 222 for (c = str; c; ) { 223 c = strchr(c, ' '); 224 if (c) 225 *c++ = '_'; 226 } 227 len -= csize; 228 str += csize; 229 } 230 231 return tsize; 232 } 233 234 int of_device_request_module(struct device *dev) 235 { 236 char *str; 237 ssize_t size; 238 int ret; 239 240 size = of_device_get_modalias(dev, NULL, 0); 241 if (size < 0) 242 return size; 243 244 str = kmalloc(size + 1, GFP_KERNEL); 245 if (!str) 246 return -ENOMEM; 247 248 of_device_get_modalias(dev, str, size); 249 str[size] = '\0'; 250 ret = request_module(str); 251 kfree(str); 252 253 return ret; 254 } 255 EXPORT_SYMBOL_GPL(of_device_request_module); 256 257 /** 258 * of_device_modalias - Fill buffer with newline terminated modalias string 259 */ 260 ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len) 261 { 262 ssize_t sl = of_device_get_modalias(dev, str, len - 2); 263 if (sl < 0) 264 return sl; 265 if (sl > len - 2) 266 return -ENOMEM; 267 268 str[sl++] = '\n'; 269 str[sl] = 0; 270 return sl; 271 } 272 EXPORT_SYMBOL_GPL(of_device_modalias); 273 274 /** 275 * of_device_uevent - Display OF related uevent information 276 */ 277 void of_device_uevent(struct device *dev, struct kobj_uevent_env *env) 278 { 279 const char *compat; 280 struct alias_prop *app; 281 struct property *p; 282 int seen = 0; 283 284 if ((!dev) || (!dev->of_node)) 285 return; 286 287 add_uevent_var(env, "OF_NAME=%s", dev->of_node->name); 288 add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node); 289 if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0) 290 add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type); 291 292 /* Since the compatible field can contain pretty much anything 293 * it's not really legal to split it out with commas. We split it 294 * up using a number of environment variables instead. */ 295 of_property_for_each_string(dev->of_node, "compatible", p, compat) { 296 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat); 297 seen++; 298 } 299 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen); 300 301 seen = 0; 302 mutex_lock(&of_mutex); 303 list_for_each_entry(app, &aliases_lookup, link) { 304 if (dev->of_node == app->np) { 305 add_uevent_var(env, "OF_ALIAS_%d=%s", seen, 306 app->alias); 307 seen++; 308 } 309 } 310 mutex_unlock(&of_mutex); 311 } 312 313 int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env) 314 { 315 int sl; 316 317 if ((!dev) || (!dev->of_node)) 318 return -ENODEV; 319 320 /* Devicetree modalias is tricky, we add it in 2 steps */ 321 if (add_uevent_var(env, "MODALIAS=")) 322 return -ENOMEM; 323 324 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1], 325 sizeof(env->buf) - env->buflen); 326 if (sl >= (sizeof(env->buf) - env->buflen)) 327 return -ENOMEM; 328 env->buflen += sl; 329 330 return 0; 331 } 332 EXPORT_SYMBOL_GPL(of_device_uevent_modalias); 333