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 = -1; 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 93 /* 94 * Set default coherent_dma_mask to 32 bit. Drivers are expected to 95 * setup the correct supported mask. 96 */ 97 if (!dev->coherent_dma_mask) 98 dev->coherent_dma_mask = DMA_BIT_MASK(32); 99 100 /* 101 * Set it to coherent_dma_mask by default if the architecture 102 * code has not set it. 103 */ 104 if (!dev->dma_mask) 105 dev->dma_mask = &dev->coherent_dma_mask; 106 107 ret = of_dma_get_range(np, &dma_addr, &paddr, &size); 108 if (ret < 0) { 109 dma_addr = offset = 0; 110 size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); 111 } else { 112 offset = PFN_DOWN(paddr - dma_addr); 113 114 /* 115 * Add a work around to treat the size as mask + 1 in case 116 * it is defined in DT as a mask. 117 */ 118 if (size & 1) { 119 dev_warn(dev, "Invalid size 0x%llx for dma-range\n", 120 size); 121 size = size + 1; 122 } 123 124 if (!size) { 125 dev_err(dev, "Adjusted size 0x%llx invalid\n", size); 126 return -EINVAL; 127 } 128 dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset); 129 } 130 131 dev->dma_pfn_offset = offset; 132 133 /* 134 * Limit coherent and dma mask based on size and default mask 135 * set by the driver. 136 */ 137 dev->coherent_dma_mask = min(dev->coherent_dma_mask, 138 DMA_BIT_MASK(ilog2(dma_addr + size))); 139 *dev->dma_mask = min((*dev->dma_mask), 140 DMA_BIT_MASK(ilog2(dma_addr + size))); 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 int cplen, i; 200 ssize_t tsize, csize, repend; 201 202 if ((!dev) || (!dev->of_node)) 203 return -ENODEV; 204 205 /* Name & Type */ 206 csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name, 207 dev->of_node->type); 208 209 /* Get compatible property if any */ 210 compat = of_get_property(dev->of_node, "compatible", &cplen); 211 if (!compat) 212 return csize; 213 214 /* Find true end (we tolerate multiple \0 at the end */ 215 for (i = (cplen - 1); i >= 0 && !compat[i]; i--) 216 cplen--; 217 if (!cplen) 218 return csize; 219 cplen++; 220 221 /* Check space (need cplen+1 chars including final \0) */ 222 tsize = csize + cplen; 223 repend = tsize; 224 225 if (csize >= len) /* @ the limit, all is already filled */ 226 return tsize; 227 228 if (tsize >= len) { /* limit compat list */ 229 cplen = len - csize - 1; 230 repend = len; 231 } 232 233 /* Copy and do char replacement */ 234 memcpy(&str[csize + 1], compat, cplen); 235 for (i = csize; i < repend; i++) { 236 char c = str[i]; 237 if (c == '\0') 238 str[i] = 'C'; 239 else if (c == ' ') 240 str[i] = '_'; 241 } 242 243 return repend; 244 } 245 246 int of_device_request_module(struct device *dev) 247 { 248 char *str; 249 ssize_t size; 250 int ret; 251 252 size = of_device_get_modalias(dev, NULL, 0); 253 if (size < 0) 254 return size; 255 256 str = kmalloc(size + 1, GFP_KERNEL); 257 if (!str) 258 return -ENOMEM; 259 260 of_device_get_modalias(dev, str, size); 261 str[size] = '\0'; 262 ret = request_module(str); 263 kfree(str); 264 265 return ret; 266 } 267 EXPORT_SYMBOL_GPL(of_device_request_module); 268 269 /** 270 * of_device_modalias - Fill buffer with newline terminated modalias string 271 */ 272 ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len) 273 { 274 ssize_t sl = of_device_get_modalias(dev, str, len - 2); 275 if (sl < 0) 276 return sl; 277 278 str[sl++] = '\n'; 279 str[sl] = 0; 280 return sl; 281 } 282 EXPORT_SYMBOL_GPL(of_device_modalias); 283 284 /** 285 * of_device_uevent - Display OF related uevent information 286 */ 287 void of_device_uevent(struct device *dev, struct kobj_uevent_env *env) 288 { 289 const char *compat; 290 struct alias_prop *app; 291 int seen = 0, cplen, sl; 292 293 if ((!dev) || (!dev->of_node)) 294 return; 295 296 add_uevent_var(env, "OF_NAME=%s", dev->of_node->name); 297 add_uevent_var(env, "OF_FULLNAME=%s", dev->of_node->full_name); 298 if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0) 299 add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type); 300 301 /* Since the compatible field can contain pretty much anything 302 * it's not really legal to split it out with commas. We split it 303 * up using a number of environment variables instead. */ 304 compat = of_get_property(dev->of_node, "compatible", &cplen); 305 while (compat && *compat && cplen > 0) { 306 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat); 307 sl = strlen(compat) + 1; 308 compat += sl; 309 cplen -= sl; 310 seen++; 311 } 312 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen); 313 314 seen = 0; 315 mutex_lock(&of_mutex); 316 list_for_each_entry(app, &aliases_lookup, link) { 317 if (dev->of_node == app->np) { 318 add_uevent_var(env, "OF_ALIAS_%d=%s", seen, 319 app->alias); 320 seen++; 321 } 322 } 323 mutex_unlock(&of_mutex); 324 } 325 326 int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env) 327 { 328 int sl; 329 330 if ((!dev) || (!dev->of_node)) 331 return -ENODEV; 332 333 /* Devicetree modalias is tricky, we add it in 2 steps */ 334 if (add_uevent_var(env, "MODALIAS=")) 335 return -ENOMEM; 336 337 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1], 338 sizeof(env->buf) - env->buflen); 339 if (sl >= (sizeof(env->buf) - env->buflen)) 340 return -ENOMEM; 341 env->buflen += sl; 342 343 return 0; 344 } 345 EXPORT_SYMBOL_GPL(of_device_uevent_modalias); 346