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