drivers/base/platform.c

   1 /*
   2  * platform.c - platform 'pseudo' bus for legacy devices
   3  *
   4  * Copyright (c) 2002-3 Patrick Mochel
   5  * Copyright (c) 2002-3 Open Source Development Labs
   6  *
   7  * This file is released under the GPLv2
   8  *
   9  * Please see Documentation/driver-model/platform.txt for more
  10  * information.
  11  */
  12
  13 #include <linux/platform_device.h>
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/dma-mapping.h>
  17 #include <linux/bootmem.h>
  18 #include <linux/err.h>
  19 #include <linux/slab.h>
  20
  21 #include "base.h"
  22
  23 #define to_platform_driver(drv) (container_of((drv), struct platform_driver, driver))
  24
  25 struct device platform_bus = {
  26         .bus_id         = "platform",
  27 };
  28 EXPORT_SYMBOL_GPL(platform_bus);
  29
  30 /**
  31  *      platform_get_resource - get a resource for a device
  32  *      @dev: platform device
  33  *      @type: resource type
  34  *      @num: resource index
  35  */
  36 struct resource *
  37 platform_get_resource(struct platform_device *dev, unsigned int type,
  38                       unsigned int num)
  39 {
  40         int i;
  41
  42         for (i = 0; i < dev->num_resources; i++) {
  43                 struct resource *r = &dev->resource[i];
  44
  45                 if ((r->flags & (IORESOURCE_IO|IORESOURCE_MEM|
  46                                  IORESOURCE_IRQ|IORESOURCE_DMA))
  47                     == type)
  48                         if (num-- == 0)
  49                                 return r;
  50         }
  51         return NULL;
  52 }
  53 EXPORT_SYMBOL_GPL(platform_get_resource);
  54
  55 /**
  56  *      platform_get_irq - get an IRQ for a device
  57  *      @dev: platform device
  58  *      @num: IRQ number index
  59  */
  60 int platform_get_irq(struct platform_device *dev, unsigned int num)
  61 {
  62         struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
  63
  64         return r ? r->start : 0;
  65 }
  66 EXPORT_SYMBOL_GPL(platform_get_irq);
  67
  68 /**
  69  *      platform_get_resource_byname - get a resource for a device by name
  70  *      @dev: platform device
  71  *      @type: resource type
  72  *      @name: resource name
  73  */
  74 struct resource *
  75 platform_get_resource_byname(struct platform_device *dev, unsigned int type,
  76                       char *name)
  77 {
  78         int i;
  79
  80         for (i = 0; i < dev->num_resources; i++) {
  81                 struct resource *r = &dev->resource[i];
  82
  83                 if ((r->flags & (IORESOURCE_IO|IORESOURCE_MEM|
  84                                  IORESOURCE_IRQ|IORESOURCE_DMA)) == type)
  85                         if (!strcmp(r->name, name))
  86                                 return r;
  87         }
  88         return NULL;
  89 }
  90 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
  91
  92 /**
  93  *      platform_get_irq - get an IRQ for a device
  94  *      @dev: platform device
  95  *      @name: IRQ name
  96  */
  97 int platform_get_irq_byname(struct platform_device *dev, char *name)
  98 {
  99         struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 100
 101         return r ? r->start : 0;
 102 }
 103 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 104
 105 /**
 106  *      platform_add_devices - add a numbers of platform devices
 107  *      @devs: array of platform devices to add
 108  *      @num: number of platform devices in array
 109  */
 110 int platform_add_devices(struct platform_device **devs, int num)
 111 {
 112         int i, ret = 0;
 113
 114         for (i = 0; i < num; i++) {
 115                 ret = platform_device_register(devs[i]);
 116                 if (ret) {
 117                         while (--i >= 0)
 118                                 platform_device_unregister(devs[i]);
 119                         break;
 120                 }
 121         }
 122
 123         return ret;
 124 }
 125 EXPORT_SYMBOL_GPL(platform_add_devices);
 126
 127 struct platform_object {
 128         struct platform_device pdev;
 129         char name[1];
 130 };
 131
 132 /**
 133  *      platform_device_put
 134  *      @pdev:  platform device to free
 135  *
 136  *      Free all memory associated with a platform device.  This function
 137  *      must _only_ be externally called in error cases.  All other usage
 138  *      is a bug.
 139  */
 140 void platform_device_put(struct platform_device *pdev)
 141 {
 142         if (pdev)
 143                 put_device(&pdev->dev);
 144 }
 145 EXPORT_SYMBOL_GPL(platform_device_put);
 146
 147 static void platform_device_release(struct device *dev)
 148 {
 149         struct platform_object *pa = container_of(dev, struct platform_object, pdev.dev);
 150
 151         kfree(pa->pdev.dev.platform_data);
 152         kfree(pa->pdev.resource);
 153         kfree(pa);
 154 }
 155
 156 /**
 157  *      platform_device_alloc
 158  *      @name:  base name of the device we're adding
 159  *      @id:    instance id
 160  *
 161  *      Create a platform device object which can have other objects attached
 162  *      to it, and which will have attached objects freed when it is released.
 163  */
 164 struct platform_device *platform_device_alloc(const char *name, unsigned int id)
 165 {
 166         struct platform_object *pa;
 167
 168         pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
 169         if (pa) {
 170                 strcpy(pa->name, name);
 171                 pa->pdev.name = pa->name;
 172                 pa->pdev.id = id;
 173                 device_initialize(&pa->pdev.dev);
 174                 pa->pdev.dev.release = platform_device_release;
 175         }
 176
 177         return pa ? &pa->pdev : NULL;
 178 }
 179 EXPORT_SYMBOL_GPL(platform_device_alloc);
 180
 181 /**
 182  *      platform_device_add_resources
 183  *      @pdev:  platform device allocated by platform_device_alloc to add resources to
 184  *      @res:   set of resources that needs to be allocated for the device
 185  *      @num:   number of resources
 186  *
 187  *      Add a copy of the resources to the platform device.  The memory
 188  *      associated with the resources will be freed when the platform
 189  *      device is released.
 190  */
 191 int platform_device_add_resources(struct platform_device *pdev, struct resource *res, unsigned int num)
 192 {
 193         struct resource *r;
 194
 195         r = kmalloc(sizeof(struct resource) * num, GFP_KERNEL);
 196         if (r) {
 197                 memcpy(r, res, sizeof(struct resource) * num);
 198                 pdev->resource = r;
 199                 pdev->num_resources = num;
 200         }
 201         return r ? 0 : -ENOMEM;
 202 }
 203 EXPORT_SYMBOL_GPL(platform_device_add_resources);
 204
 205 /**
 206  *      platform_device_add_data
 207  *      @pdev:  platform device allocated by platform_device_alloc to add resources to
 208  *      @data:  platform specific data for this platform device
 209  *      @size:  size of platform specific data
 210  *
 211  *      Add a copy of platform specific data to the platform device's platform_data
 212  *      pointer.  The memory associated with the platform data will be freed
 213  *      when the platform device is released.
 214  */
 215 int platform_device_add_data(struct platform_device *pdev, void *data, size_t size)
 216 {
 217         void *d;
 218
 219         d = kmalloc(size, GFP_KERNEL);
 220         if (d) {
 221                 memcpy(d, data, size);
 222                 pdev->dev.platform_data = d;
 223         }
 224         return d ? 0 : -ENOMEM;
 225 }
 226 EXPORT_SYMBOL_GPL(platform_device_add_data);
 227
 228 /**
 229  *      platform_device_add - add a platform device to device hierarchy
 230  *      @pdev:  platform device we're adding
 231  *
 232  *      This is part 2 of platform_device_register(), though may be called
 233  *      separately _iff_ pdev was allocated by platform_device_alloc().
 234  */
 235 int platform_device_add(struct platform_device *pdev)
 236 {
 237         int i, ret = 0;
 238
 239         if (!pdev)
 240                 return -EINVAL;
 241
 242         if (!pdev->dev.parent)
 243                 pdev->dev.parent = &platform_bus;
 244
 245         pdev->dev.bus = &platform_bus_type;
 246
 247         if (pdev->id != -1)
 248                 snprintf(pdev->dev.bus_id, BUS_ID_SIZE, "%s.%u", pdev->name, pdev->id);
 249         else
 250                 strlcpy(pdev->dev.bus_id, pdev->name, BUS_ID_SIZE);
 251
 252         for (i = 0; i < pdev->num_resources; i++) {
 253                 struct resource *p, *r = &pdev->resource[i];
 254
 255                 if (r->name == NULL)
 256                         r->name = pdev->dev.bus_id;
 257
 258                 p = r->parent;
 259                 if (!p) {
 260                         if (r->flags & IORESOURCE_MEM)
 261                                 p = &iomem_resource;
 262                         else if (r->flags & IORESOURCE_IO)
 263                                 p = &ioport_resource;
 264                 }
 265
 266                 if (p && insert_resource(p, r)) {
 267                         printk(KERN_ERR
 268                                "%s: failed to claim resource %d\n",
 269                                pdev->dev.bus_id, i);
 270                         ret = -EBUSY;
 271                         goto failed;
 272                 }
 273         }
 274
 275         pr_debug("Registering platform device '%s'. Parent at %s\n",
 276                  pdev->dev.bus_id, pdev->dev.parent->bus_id);
 277
 278         ret = device_register(&pdev->dev);
 279         if (ret == 0)
 280                 return ret;
 281
 282  failed:
 283         while (--i >= 0)
 284                 if (pdev->resource[i].flags & (IORESOURCE_MEM|IORESOURCE_IO))
 285                         release_resource(&pdev->resource[i]);
 286         return ret;
 287 }
 288 EXPORT_SYMBOL_GPL(platform_device_add);
 289
 290 /**
 291  *      platform_device_del - remove a platform-level device
 292  *      @pdev:  platform device we're removing
 293  *
 294  *      Note that this function will also release all memory- and port-based
 295  *      resources owned by the device (@dev->resource).
 296  */
 297 void platform_device_del(struct platform_device *pdev)
 298 {
 299         int i;
 300
 301         if (pdev) {
 302                 for (i = 0; i < pdev->num_resources; i++) {
 303                         struct resource *r = &pdev->resource[i];
 304                         if (r->flags & (IORESOURCE_MEM|IORESOURCE_IO))
 305                                 release_resource(r);
 306                 }
 307
 308                 device_del(&pdev->dev);
 309         }
 310 }
 311 EXPORT_SYMBOL_GPL(platform_device_del);
 312
 313 /**
 314  *      platform_device_register - add a platform-level device
 315  *      @pdev:  platform device we're adding
 316  *
 317  */
 318 int platform_device_register(struct platform_device * pdev)
 319 {
 320         device_initialize(&pdev->dev);
 321         return platform_device_add(pdev);
 322 }
 323 EXPORT_SYMBOL_GPL(platform_device_register);
 324
 325 /**
 326  *      platform_device_unregister - unregister a platform-level device
 327  *      @pdev:  platform device we're unregistering
 328  *
 329  *      Unregistration is done in 2 steps. Fisrt we release all resources
 330  *      and remove it from the sybsystem, then we drop reference count by
 331  *      calling platform_device_put().
 332  */
 333 void platform_device_unregister(struct platform_device * pdev)
 334 {
 335         platform_device_del(pdev);
 336         platform_device_put(pdev);
 337 }
 338 EXPORT_SYMBOL_GPL(platform_device_unregister);
 339
 340 /**
 341  *      platform_device_register_simple
 342  *      @name:  base name of the device we're adding
 343  *      @id:    instance id
 344  *      @res:   set of resources that needs to be allocated for the device
 345  *      @num:   number of resources
 346  *
 347  *      This function creates a simple platform device that requires minimal
 348  *      resource and memory management. Canned release function freeing
 349  *      memory allocated for the device allows drivers using such devices
 350  *      to be unloaded iwithout waiting for the last reference to the device
 351  *      to be dropped.
 352  */
 353 struct platform_device *platform_device_register_simple(char *name, unsigned int id,
 354                                                         struct resource *res, unsigned int num)
 355 {
 356         struct platform_device *pdev;
 357         int retval;
 358
 359         pdev = platform_device_alloc(name, id);
 360         if (!pdev) {
 361                 retval = -ENOMEM;
 362                 goto error;
 363         }
 364
 365         if (num) {
 366                 retval = platform_device_add_resources(pdev, res, num);
 367                 if (retval)
 368                         goto error;
 369         }
 370
 371         retval = platform_device_add(pdev);
 372         if (retval)
 373                 goto error;
 374
 375         return pdev;
 376
 377 error:
 378         platform_device_put(pdev);
 379         return ERR_PTR(retval);
 380 }
 381 EXPORT_SYMBOL_GPL(platform_device_register_simple);
 382
 383 static int platform_drv_probe(struct device *_dev)
 384 {
 385         struct platform_driver *drv = to_platform_driver(_dev->driver);
 386         struct platform_device *dev = to_platform_device(_dev);
 387
 388         return drv->probe(dev);
 389 }
 390
 391 static int platform_drv_remove(struct device *_dev)
 392 {
 393         struct platform_driver *drv = to_platform_driver(_dev->driver);
 394         struct platform_device *dev = to_platform_device(_dev);
 395
 396         return drv->remove(dev);
 397 }
 398
 399 static void platform_drv_shutdown(struct device *_dev)
 400 {
 401         struct platform_driver *drv = to_platform_driver(_dev->driver);
 402         struct platform_device *dev = to_platform_device(_dev);
 403
 404         drv->shutdown(dev);
 405 }
 406
 407 static int platform_drv_suspend(struct device *_dev, pm_message_t state)
 408 {
 409         struct platform_driver *drv = to_platform_driver(_dev->driver);
 410         struct platform_device *dev = to_platform_device(_dev);
 411
 412         return drv->suspend(dev, state);
 413 }
 414
 415 static int platform_drv_resume(struct device *_dev)
 416 {
 417         struct platform_driver *drv = to_platform_driver(_dev->driver);
 418         struct platform_device *dev = to_platform_device(_dev);
 419
 420         return drv->resume(dev);
 421 }
 422
 423 /**
 424  *      platform_driver_register
 425  *      @drv: platform driver structure
 426  */
 427 int platform_driver_register(struct platform_driver *drv)
 428 {
 429         drv->driver.bus = &platform_bus_type;
 430         if (drv->probe)
 431                 drv->driver.probe = platform_drv_probe;
 432         if (drv->remove)
 433                 drv->driver.remove = platform_drv_remove;
 434         if (drv->shutdown)
 435                 drv->driver.shutdown = platform_drv_shutdown;
 436         if (drv->suspend)
 437                 drv->driver.suspend = platform_drv_suspend;
 438         if (drv->resume)
 439                 drv->driver.resume = platform_drv_resume;
 440         return driver_register(&drv->driver);
 441 }
 442 EXPORT_SYMBOL_GPL(platform_driver_register);
 443
 444 /**
 445  *      platform_driver_unregister
 446  *      @drv: platform driver structure
 447  */
 448 void platform_driver_unregister(struct platform_driver *drv)
 449 {
 450         driver_unregister(&drv->driver);
 451 }
 452 EXPORT_SYMBOL_GPL(platform_driver_unregister);
 453
 454
 455 /**
 456  *      platform_match - bind platform device to platform driver.
 457  *      @dev:   device.
 458  *      @drv:   driver.
 459  *
 460  *      Platform device IDs are assumed to be encoded like this:
 461  *      "<name><instance>", where <name> is a short description of the
 462  *      type of device, like "pci" or "floppy", and <instance> is the
 463  *      enumerated instance of the device, like '0' or '42'.
 464  *      Driver IDs are simply "<name>".
 465  *      So, extract the <name> from the platform_device structure,
 466  *      and compare it against the name of the driver. Return whether
 467  *      they match or not.
 468  */
 469
 470 static int platform_match(struct device * dev, struct device_driver * drv)
 471 {
 472         struct platform_device *pdev = container_of(dev, struct platform_device, dev);
 473
 474         return (strncmp(pdev->name, drv->name, BUS_ID_SIZE) == 0);
 475 }
 476
 477 static int platform_suspend(struct device * dev, pm_message_t state)
 478 {
 479         int ret = 0;
 480
 481         if (dev->driver && dev->driver->suspend)
 482                 ret = dev->driver->suspend(dev, state);
 483
 484         return ret;
 485 }
 486
 487 static int platform_resume(struct device * dev)
 488 {
 489         int ret = 0;
 490
 491         if (dev->driver && dev->driver->resume)
 492                 ret = dev->driver->resume(dev);
 493
 494         return ret;
 495 }
 496
 497 struct bus_type platform_bus_type = {
 498         .name           = "platform",
 499         .match          = platform_match,
 500         .suspend        = platform_suspend,
 501         .resume         = platform_resume,
 502 };
 503 EXPORT_SYMBOL_GPL(platform_bus_type);
 504
 505 int __init platform_bus_init(void)
 506 {
 507         device_register(&platform_bus);
 508         return bus_register(&platform_bus_type);
 509 }
 510
 511 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
 512 u64 dma_get_required_mask(struct device *dev)
 513 {
 514         u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
 515         u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
 516         u64 mask;
 517
 518         if (!high_totalram) {
 519                 /* convert to mask just covering totalram */
 520                 low_totalram = (1 << (fls(low_totalram) - 1));
 521                 low_totalram += low_totalram - 1;
 522                 mask = low_totalram;
 523         } else {
 524                 high_totalram = (1 << (fls(high_totalram) - 1));
 525                 high_totalram += high_totalram - 1;
 526                 mask = (((u64)high_totalram) << 32) + 0xffffffff;
 527         }
 528         return mask & *dev->dma_mask;
 529 }
 530 EXPORT_SYMBOL_GPL(dma_get_required_mask);
 531 #endif