1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/string.h> 3 #include <linux/kernel.h> 4 #include <linux/of.h> 5 #include <linux/of_device.h> 6 #include <linux/of_address.h> 7 #include <linux/of_iommu.h> 8 #include <linux/dma-mapping.h> 9 #include <linux/init.h> 10 #include <linux/module.h> 11 #include <linux/mod_devicetable.h> 12 #include <linux/slab.h> 13 #include <linux/platform_device.h> 14 15 #include <asm/errno.h> 16 #include "of_private.h" 17 18 /** 19 * of_match_device - Tell if a struct device matches an of_device_id list 20 * @ids: array of of device match structures to search in 21 * @dev: the of device structure to match against 22 * 23 * Used by a driver to check whether an platform_device present in the 24 * system is in its list of supported devices. 25 */ 26 const struct of_device_id *of_match_device(const struct of_device_id *matches, 27 const struct device *dev) 28 { 29 if ((!matches) || (!dev->of_node)) 30 return NULL; 31 return of_match_node(matches, dev->of_node); 32 } 33 EXPORT_SYMBOL(of_match_device); 34 35 struct platform_device *of_dev_get(struct platform_device *dev) 36 { 37 struct device *tmp; 38 39 if (!dev) 40 return NULL; 41 tmp = get_device(&dev->dev); 42 if (tmp) 43 return to_platform_device(tmp); 44 else 45 return NULL; 46 } 47 EXPORT_SYMBOL(of_dev_get); 48 49 void of_dev_put(struct platform_device *dev) 50 { 51 if (dev) 52 put_device(&dev->dev); 53 } 54 EXPORT_SYMBOL(of_dev_put); 55 56 int of_device_add(struct platform_device *ofdev) 57 { 58 BUG_ON(ofdev->dev.of_node == NULL); 59 60 /* name and id have to be set so that the platform bus doesn't get 61 * confused on matching */ 62 ofdev->name = dev_name(&ofdev->dev); 63 ofdev->id = PLATFORM_DEVID_NONE; 64 65 /* 66 * If this device has not binding numa node in devicetree, that is 67 * of_node_to_nid returns NUMA_NO_NODE. device_add will assume that this 68 * device is on the same node as the parent. 69 */ 70 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node)); 71 72 return device_add(&ofdev->dev); 73 } 74 75 /** 76 * of_dma_configure - Setup DMA configuration 77 * @dev: Device to apply DMA configuration 78 * @np: Pointer to OF node having DMA configuration 79 * 80 * Try to get devices's DMA configuration from DT and update it 81 * accordingly. 82 * 83 * If platform code needs to use its own special DMA configuration, it 84 * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events 85 * to fix up DMA configuration. 86 */ 87 int of_dma_configure(struct device *dev, struct device_node *np) 88 { 89 u64 dma_addr, paddr, size = 0; 90 int ret; 91 bool coherent; 92 unsigned long offset; 93 const struct iommu_ops *iommu; 94 u64 mask; 95 96 ret = of_dma_get_range(np, &dma_addr, &paddr, &size); 97 if (ret < 0) { 98 /* 99 * For legacy reasons, we have to assume some devices need 100 * DMA configuration regardless of whether "dma-ranges" is 101 * correctly specified or not. 102 */ 103 if (!dev->bus->force_dma) 104 return ret == -ENODEV ? 0 : ret; 105 106 dma_addr = offset = 0; 107 } else { 108 offset = PFN_DOWN(paddr - dma_addr); 109 110 /* 111 * Add a work around to treat the size as mask + 1 in case 112 * it is defined in DT as a mask. 113 */ 114 if (size & 1) { 115 dev_warn(dev, "Invalid size 0x%llx for dma-range\n", 116 size); 117 size = size + 1; 118 } 119 120 if (!size) { 121 dev_err(dev, "Adjusted size 0x%llx invalid\n", size); 122 return -EINVAL; 123 } 124 dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset); 125 } 126 127 /* 128 * Set default coherent_dma_mask to 32 bit. Drivers are expected to 129 * setup the correct supported mask. 130 */ 131 if (!dev->coherent_dma_mask) 132 dev->coherent_dma_mask = DMA_BIT_MASK(32); 133 /* 134 * Set it to coherent_dma_mask by default if the architecture 135 * code has not set it. 136 */ 137 if (!dev->dma_mask) 138 dev->dma_mask = &dev->coherent_dma_mask; 139 140 if (!size) 141 size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); 142 143 dev->dma_pfn_offset = offset; 144 145 /* 146 * Limit coherent and dma mask based on size and default mask 147 * set by the driver. 148 */ 149 mask = DMA_BIT_MASK(ilog2(dma_addr + size - 1) + 1); 150 dev->coherent_dma_mask &= mask; 151 *dev->dma_mask &= mask; 152 153 coherent = of_dma_is_coherent(np); 154 dev_dbg(dev, "device is%sdma coherent\n", 155 coherent ? " " : " not "); 156 157 iommu = of_iommu_configure(dev, np); 158 if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER) 159 return -EPROBE_DEFER; 160 161 dev_dbg(dev, "device is%sbehind an iommu\n", 162 iommu ? " " : " not "); 163 164 arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent); 165 166 return 0; 167 } 168 EXPORT_SYMBOL_GPL(of_dma_configure); 169 170 /** 171 * of_dma_deconfigure - Clean up DMA configuration 172 * @dev: Device for which to clean up DMA configuration 173 * 174 * Clean up all configuration performed by of_dma_configure_ops() and free all 175 * resources that have been allocated. 176 */ 177 void of_dma_deconfigure(struct device *dev) 178 { 179 arch_teardown_dma_ops(dev); 180 } 181 182 int of_device_register(struct platform_device *pdev) 183 { 184 device_initialize(&pdev->dev); 185 return of_device_add(pdev); 186 } 187 EXPORT_SYMBOL(of_device_register); 188 189 void of_device_unregister(struct platform_device *ofdev) 190 { 191 device_unregister(&ofdev->dev); 192 } 193 EXPORT_SYMBOL(of_device_unregister); 194 195 const void *of_device_get_match_data(const struct device *dev) 196 { 197 const struct of_device_id *match; 198 199 match = of_match_device(dev->driver->of_match_table, dev); 200 if (!match) 201 return NULL; 202 203 return match->data; 204 } 205 EXPORT_SYMBOL(of_device_get_match_data); 206 207 static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len) 208 { 209 const char *compat; 210 char *c; 211 struct property *p; 212 ssize_t csize; 213 ssize_t tsize; 214 215 if ((!dev) || (!dev->of_node)) 216 return -ENODEV; 217 218 /* Name & Type */ 219 csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name, 220 dev->of_node->type); 221 tsize = csize; 222 len -= csize; 223 if (str) 224 str += csize; 225 226 of_property_for_each_string(dev->of_node, "compatible", p, compat) { 227 csize = strlen(compat) + 1; 228 tsize += csize; 229 if (csize > len) 230 continue; 231 232 csize = snprintf(str, len, "C%s", compat); 233 for (c = str; c; ) { 234 c = strchr(c, ' '); 235 if (c) 236 *c++ = '_'; 237 } 238 len -= csize; 239 str += csize; 240 } 241 242 return tsize; 243 } 244 245 int of_device_request_module(struct device *dev) 246 { 247 char *str; 248 ssize_t size; 249 int ret; 250 251 size = of_device_get_modalias(dev, NULL, 0); 252 if (size < 0) 253 return size; 254 255 str = kmalloc(size + 1, GFP_KERNEL); 256 if (!str) 257 return -ENOMEM; 258 259 of_device_get_modalias(dev, str, size); 260 str[size] = '\0'; 261 ret = request_module(str); 262 kfree(str); 263 264 return ret; 265 } 266 EXPORT_SYMBOL_GPL(of_device_request_module); 267 268 /** 269 * of_device_modalias - Fill buffer with newline terminated modalias string 270 */ 271 ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len) 272 { 273 ssize_t sl = of_device_get_modalias(dev, str, len - 2); 274 if (sl < 0) 275 return sl; 276 if (sl > len - 2) 277 return -ENOMEM; 278 279 str[sl++] = '\n'; 280 str[sl] = 0; 281 return sl; 282 } 283 EXPORT_SYMBOL_GPL(of_device_modalias); 284 285 /** 286 * of_device_uevent - Display OF related uevent information 287 */ 288 void of_device_uevent(struct device *dev, struct kobj_uevent_env *env) 289 { 290 const char *compat; 291 struct alias_prop *app; 292 struct property *p; 293 int seen = 0; 294 295 if ((!dev) || (!dev->of_node)) 296 return; 297 298 add_uevent_var(env, "OF_NAME=%s", dev->of_node->name); 299 add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node); 300 if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0) 301 add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type); 302 303 /* Since the compatible field can contain pretty much anything 304 * it's not really legal to split it out with commas. We split it 305 * up using a number of environment variables instead. */ 306 of_property_for_each_string(dev->of_node, "compatible", p, compat) { 307 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat); 308 seen++; 309 } 310 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen); 311 312 seen = 0; 313 mutex_lock(&of_mutex); 314 list_for_each_entry(app, &aliases_lookup, link) { 315 if (dev->of_node == app->np) { 316 add_uevent_var(env, "OF_ALIAS_%d=%s", seen, 317 app->alias); 318 seen++; 319 } 320 } 321 mutex_unlock(&of_mutex); 322 } 323 324 int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env) 325 { 326 int sl; 327 328 if ((!dev) || (!dev->of_node)) 329 return -ENODEV; 330 331 /* Devicetree modalias is tricky, we add it in 2 steps */ 332 if (add_uevent_var(env, "MODALIAS=")) 333 return -ENOMEM; 334 335 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1], 336 sizeof(env->buf) - env->buflen); 337 if (sl >= (sizeof(env->buf) - env->buflen)) 338 return -ENOMEM; 339 env->buflen += sl; 340 341 return 0; 342 } 343 EXPORT_SYMBOL_GPL(of_device_uevent_modalias); 344