2 * platform.c - platform 'pseudo' bus for legacy devices
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
7 * This file is released under the GPLv2
9 * Please see Documentation/driver-model/platform.txt for more
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>
23 #define to_platform_driver(drv) (container_of((drv), struct platform_driver, driver))
25 struct device platform_bus = {
28 EXPORT_SYMBOL_GPL(platform_bus);
31 * platform_get_resource - get a resource for a device
32 * @dev: platform device
33 * @type: resource type
34 * @num: resource index
37 platform_get_resource(struct platform_device *dev, unsigned int type,
42 for (i = 0; i < dev->num_resources; i++) {
43 struct resource *r = &dev->resource[i];
45 if ((r->flags & (IORESOURCE_IO|IORESOURCE_MEM|
46 IORESOURCE_IRQ|IORESOURCE_DMA))
53 EXPORT_SYMBOL_GPL(platform_get_resource);
56 * platform_get_irq - get an IRQ for a device
57 * @dev: platform device
58 * @num: IRQ number index
60 int platform_get_irq(struct platform_device *dev, unsigned int num)
62 struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
64 return r ? r->start : -ENXIO;
66 EXPORT_SYMBOL_GPL(platform_get_irq);
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
75 platform_get_resource_byname(struct platform_device *dev, unsigned int type,
80 for (i = 0; i < dev->num_resources; i++) {
81 struct resource *r = &dev->resource[i];
83 if ((r->flags & (IORESOURCE_IO|IORESOURCE_MEM|
84 IORESOURCE_IRQ|IORESOURCE_DMA)) == type)
85 if (!strcmp(r->name, name))
90 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
93 * platform_get_irq - get an IRQ for a device
94 * @dev: platform device
97 int platform_get_irq_byname(struct platform_device *dev, char *name)
99 struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
101 return r ? r->start : -ENXIO;
103 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
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
110 int platform_add_devices(struct platform_device **devs, int num)
114 for (i = 0; i < num; i++) {
115 ret = platform_device_register(devs[i]);
118 platform_device_unregister(devs[i]);
125 EXPORT_SYMBOL_GPL(platform_add_devices);
127 struct platform_object {
128 struct platform_device pdev;
133 * platform_device_put
134 * @pdev: platform device to free
136 * Free all memory associated with a platform device. This function
137 * must _only_ be externally called in error cases. All other usage
140 void platform_device_put(struct platform_device *pdev)
143 put_device(&pdev->dev);
145 EXPORT_SYMBOL_GPL(platform_device_put);
147 static void platform_device_release(struct device *dev)
149 struct platform_object *pa = container_of(dev, struct platform_object, pdev.dev);
151 kfree(pa->pdev.dev.platform_data);
152 kfree(pa->pdev.resource);
157 * platform_device_alloc
158 * @name: base name of the device we're adding
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.
164 struct platform_device *platform_device_alloc(const char *name, unsigned int id)
166 struct platform_object *pa;
168 pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
170 strcpy(pa->name, name);
171 pa->pdev.name = pa->name;
173 device_initialize(&pa->pdev.dev);
174 pa->pdev.dev.release = platform_device_release;
177 return pa ? &pa->pdev : NULL;
179 EXPORT_SYMBOL_GPL(platform_device_alloc);
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
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.
191 int platform_device_add_resources(struct platform_device *pdev, struct resource *res, unsigned int num)
195 r = kmalloc(sizeof(struct resource) * num, GFP_KERNEL);
197 memcpy(r, res, sizeof(struct resource) * num);
199 pdev->num_resources = num;
201 return r ? 0 : -ENOMEM;
203 EXPORT_SYMBOL_GPL(platform_device_add_resources);
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
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.
215 int platform_device_add_data(struct platform_device *pdev, void *data, size_t size)
219 d = kmalloc(size, GFP_KERNEL);
221 memcpy(d, data, size);
222 pdev->dev.platform_data = d;
224 return d ? 0 : -ENOMEM;
226 EXPORT_SYMBOL_GPL(platform_device_add_data);
229 * platform_device_add - add a platform device to device hierarchy
230 * @pdev: platform device we're adding
232 * This is part 2 of platform_device_register(), though may be called
233 * separately _iff_ pdev was allocated by platform_device_alloc().
235 int platform_device_add(struct platform_device *pdev)
242 if (!pdev->dev.parent)
243 pdev->dev.parent = &platform_bus;
245 pdev->dev.bus = &platform_bus_type;
248 snprintf(pdev->dev.bus_id, BUS_ID_SIZE, "%s.%u", pdev->name, pdev->id);
250 strlcpy(pdev->dev.bus_id, pdev->name, BUS_ID_SIZE);
252 for (i = 0; i < pdev->num_resources; i++) {
253 struct resource *p, *r = &pdev->resource[i];
256 r->name = pdev->dev.bus_id;
260 if (r->flags & IORESOURCE_MEM)
262 else if (r->flags & IORESOURCE_IO)
263 p = &ioport_resource;
266 if (p && insert_resource(p, r)) {
268 "%s: failed to claim resource %d\n",
269 pdev->dev.bus_id, i);
275 pr_debug("Registering platform device '%s'. Parent at %s\n",
276 pdev->dev.bus_id, pdev->dev.parent->bus_id);
278 ret = device_add(&pdev->dev);
284 if (pdev->resource[i].flags & (IORESOURCE_MEM|IORESOURCE_IO))
285 release_resource(&pdev->resource[i]);
288 EXPORT_SYMBOL_GPL(platform_device_add);
291 * platform_device_del - remove a platform-level device
292 * @pdev: platform device we're removing
294 * Note that this function will also release all memory- and port-based
295 * resources owned by the device (@dev->resource).
297 void platform_device_del(struct platform_device *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))
308 device_del(&pdev->dev);
311 EXPORT_SYMBOL_GPL(platform_device_del);
314 * platform_device_register - add a platform-level device
315 * @pdev: platform device we're adding
318 int platform_device_register(struct platform_device * pdev)
320 device_initialize(&pdev->dev);
321 return platform_device_add(pdev);
323 EXPORT_SYMBOL_GPL(platform_device_register);
326 * platform_device_unregister - unregister a platform-level device
327 * @pdev: platform device we're unregistering
329 * Unregistration is done in 2 steps. First we release all resources
330 * and remove it from the subsystem, then we drop reference count by
331 * calling platform_device_put().
333 void platform_device_unregister(struct platform_device * pdev)
335 platform_device_del(pdev);
336 platform_device_put(pdev);
338 EXPORT_SYMBOL_GPL(platform_device_unregister);
341 * platform_device_register_simple
342 * @name: base name of the device we're adding
344 * @res: set of resources that needs to be allocated for the device
345 * @num: number of resources
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
353 struct platform_device *platform_device_register_simple(char *name, unsigned int id,
354 struct resource *res, unsigned int num)
356 struct platform_device *pdev;
359 pdev = platform_device_alloc(name, id);
366 retval = platform_device_add_resources(pdev, res, num);
371 retval = platform_device_add(pdev);
378 platform_device_put(pdev);
379 return ERR_PTR(retval);
381 EXPORT_SYMBOL_GPL(platform_device_register_simple);
383 static int platform_drv_probe(struct device *_dev)
385 struct platform_driver *drv = to_platform_driver(_dev->driver);
386 struct platform_device *dev = to_platform_device(_dev);
388 return drv->probe(dev);
391 static int platform_drv_remove(struct device *_dev)
393 struct platform_driver *drv = to_platform_driver(_dev->driver);
394 struct platform_device *dev = to_platform_device(_dev);
396 return drv->remove(dev);
399 static void platform_drv_shutdown(struct device *_dev)
401 struct platform_driver *drv = to_platform_driver(_dev->driver);
402 struct platform_device *dev = to_platform_device(_dev);
407 static int platform_drv_suspend(struct device *_dev, pm_message_t state)
409 struct platform_driver *drv = to_platform_driver(_dev->driver);
410 struct platform_device *dev = to_platform_device(_dev);
412 return drv->suspend(dev, state);
415 static int platform_drv_resume(struct device *_dev)
417 struct platform_driver *drv = to_platform_driver(_dev->driver);
418 struct platform_device *dev = to_platform_device(_dev);
420 return drv->resume(dev);
424 * platform_driver_register
425 * @drv: platform driver structure
427 int platform_driver_register(struct platform_driver *drv)
429 drv->driver.bus = &platform_bus_type;
431 drv->driver.probe = platform_drv_probe;
433 drv->driver.remove = platform_drv_remove;
435 drv->driver.shutdown = platform_drv_shutdown;
437 drv->driver.suspend = platform_drv_suspend;
439 drv->driver.resume = platform_drv_resume;
440 return driver_register(&drv->driver);
442 EXPORT_SYMBOL_GPL(platform_driver_register);
445 * platform_driver_unregister
446 * @drv: platform driver structure
448 void platform_driver_unregister(struct platform_driver *drv)
450 driver_unregister(&drv->driver);
452 EXPORT_SYMBOL_GPL(platform_driver_unregister);
455 /* modalias support enables more hands-off userspace setup:
456 * (a) environment variable lets new-style hotplug events work once system is
457 * fully running: "modprobe $MODALIAS"
458 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
459 * mishandled before system is fully running: "modprobe $(cat modalias)"
462 modalias_show(struct device *dev, struct device_attribute *a, char *buf)
464 struct platform_device *pdev = to_platform_device(dev);
465 int len = snprintf(buf, PAGE_SIZE, "%s\n", pdev->name);
467 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
470 static struct device_attribute platform_dev_attrs[] = {
475 static int platform_uevent(struct device *dev, char **envp, int num_envp,
476 char *buffer, int buffer_size)
478 struct platform_device *pdev = to_platform_device(dev);
481 snprintf(buffer, buffer_size, "MODALIAS=%s", pdev->name);
487 * platform_match - bind platform device to platform driver.
491 * Platform device IDs are assumed to be encoded like this:
492 * "<name><instance>", where <name> is a short description of the
493 * type of device, like "pci" or "floppy", and <instance> is the
494 * enumerated instance of the device, like '0' or '42'.
495 * Driver IDs are simply "<name>".
496 * So, extract the <name> from the platform_device structure,
497 * and compare it against the name of the driver. Return whether
501 static int platform_match(struct device * dev, struct device_driver * drv)
503 struct platform_device *pdev = container_of(dev, struct platform_device, dev);
505 return (strncmp(pdev->name, drv->name, BUS_ID_SIZE) == 0);
508 static int platform_suspend(struct device *dev, pm_message_t mesg)
512 if (dev->driver && dev->driver->suspend)
513 ret = dev->driver->suspend(dev, mesg);
518 static int platform_suspend_late(struct device *dev, pm_message_t mesg)
520 struct platform_driver *drv = to_platform_driver(dev->driver);
521 struct platform_device *pdev = container_of(dev, struct platform_device, dev);
524 if (dev->driver && drv->suspend_late)
525 ret = drv->suspend_late(pdev, mesg);
530 static int platform_resume_early(struct device *dev)
532 struct platform_driver *drv = to_platform_driver(dev->driver);
533 struct platform_device *pdev = container_of(dev, struct platform_device, dev);
536 if (dev->driver && drv->resume_early)
537 ret = drv->resume_early(pdev);
542 static int platform_resume(struct device * dev)
546 if (dev->driver && dev->driver->resume)
547 ret = dev->driver->resume(dev);
552 struct bus_type platform_bus_type = {
554 .dev_attrs = platform_dev_attrs,
555 .match = platform_match,
556 .uevent = platform_uevent,
557 .suspend = platform_suspend,
558 .suspend_late = platform_suspend_late,
559 .resume_early = platform_resume_early,
560 .resume = platform_resume,
562 EXPORT_SYMBOL_GPL(platform_bus_type);
564 int __init platform_bus_init(void)
566 device_register(&platform_bus);
567 return bus_register(&platform_bus_type);
570 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
571 u64 dma_get_required_mask(struct device *dev)
573 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
574 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
577 if (!high_totalram) {
578 /* convert to mask just covering totalram */
579 low_totalram = (1 << (fls(low_totalram) - 1));
580 low_totalram += low_totalram - 1;
583 high_totalram = (1 << (fls(high_totalram) - 1));
584 high_totalram += high_totalram - 1;
585 mask = (((u64)high_totalram) << 32) + 0xffffffff;
587 return mask & *dev->dma_mask;
589 EXPORT_SYMBOL_GPL(dma_get_required_mask);