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 void 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 = 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; 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 dev_dbg(dev, "device is%sbehind an iommu\n", 148 iommu ? " " : " not "); 149 150 arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent); 151 } 152 EXPORT_SYMBOL_GPL(of_dma_configure); 153 154 int of_device_register(struct platform_device *pdev) 155 { 156 device_initialize(&pdev->dev); 157 return of_device_add(pdev); 158 } 159 EXPORT_SYMBOL(of_device_register); 160 161 void of_device_unregister(struct platform_device *ofdev) 162 { 163 device_unregister(&ofdev->dev); 164 } 165 EXPORT_SYMBOL(of_device_unregister); 166 167 const void *of_device_get_match_data(const struct device *dev) 168 { 169 const struct of_device_id *match; 170 171 match = of_match_device(dev->driver->of_match_table, dev); 172 if (!match) 173 return NULL; 174 175 return match->data; 176 } 177 EXPORT_SYMBOL(of_device_get_match_data); 178 179 ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len) 180 { 181 const char *compat; 182 int cplen, i; 183 ssize_t tsize, csize, repend; 184 185 if ((!dev) || (!dev->of_node)) 186 return -ENODEV; 187 188 /* Name & Type */ 189 csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name, 190 dev->of_node->type); 191 192 /* Get compatible property if any */ 193 compat = of_get_property(dev->of_node, "compatible", &cplen); 194 if (!compat) 195 return csize; 196 197 /* Find true end (we tolerate multiple \0 at the end */ 198 for (i = (cplen - 1); i >= 0 && !compat[i]; i--) 199 cplen--; 200 if (!cplen) 201 return csize; 202 cplen++; 203 204 /* Check space (need cplen+1 chars including final \0) */ 205 tsize = csize + cplen; 206 repend = tsize; 207 208 if (csize >= len) /* @ the limit, all is already filled */ 209 return tsize; 210 211 if (tsize >= len) { /* limit compat list */ 212 cplen = len - csize - 1; 213 repend = len; 214 } 215 216 /* Copy and do char replacement */ 217 memcpy(&str[csize + 1], compat, cplen); 218 for (i = csize; i < repend; i++) { 219 char c = str[i]; 220 if (c == '\0') 221 str[i] = 'C'; 222 else if (c == ' ') 223 str[i] = '_'; 224 } 225 226 return tsize; 227 } 228 229 /** 230 * of_device_uevent - Display OF related uevent information 231 */ 232 void of_device_uevent(struct device *dev, struct kobj_uevent_env *env) 233 { 234 const char *compat; 235 struct alias_prop *app; 236 int seen = 0, cplen, sl; 237 238 if ((!dev) || (!dev->of_node)) 239 return; 240 241 add_uevent_var(env, "OF_NAME=%s", dev->of_node->name); 242 add_uevent_var(env, "OF_FULLNAME=%s", dev->of_node->full_name); 243 if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0) 244 add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type); 245 246 /* Since the compatible field can contain pretty much anything 247 * it's not really legal to split it out with commas. We split it 248 * up using a number of environment variables instead. */ 249 compat = of_get_property(dev->of_node, "compatible", &cplen); 250 while (compat && *compat && cplen > 0) { 251 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat); 252 sl = strlen(compat) + 1; 253 compat += sl; 254 cplen -= sl; 255 seen++; 256 } 257 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen); 258 259 seen = 0; 260 mutex_lock(&of_mutex); 261 list_for_each_entry(app, &aliases_lookup, link) { 262 if (dev->of_node == app->np) { 263 add_uevent_var(env, "OF_ALIAS_%d=%s", seen, 264 app->alias); 265 seen++; 266 } 267 } 268 mutex_unlock(&of_mutex); 269 } 270 271 int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env) 272 { 273 int sl; 274 275 if ((!dev) || (!dev->of_node)) 276 return -ENODEV; 277 278 /* Devicetree modalias is tricky, we add it in 2 steps */ 279 if (add_uevent_var(env, "MODALIAS=")) 280 return -ENOMEM; 281 282 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1], 283 sizeof(env->buf) - env->buflen); 284 if (sl >= (sizeof(env->buf) - env->buflen)) 285 return -ENOMEM; 286 env->buflen += sl; 287 288 return 0; 289 } 290