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/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>
20 struct device platform_bus = {
25 * platform_get_resource - get a resource for a device
26 * @dev: platform device
27 * @type: resource type
28 * @num: resource index
31 platform_get_resource(struct platform_device *dev, unsigned int type,
36 for (i = 0; i < dev->num_resources; i++) {
37 struct resource *r = &dev->resource[i];
39 if ((r->flags & (IORESOURCE_IO|IORESOURCE_MEM|
40 IORESOURCE_IRQ|IORESOURCE_DMA))
49 * platform_get_irq - get an IRQ for a device
50 * @dev: platform device
51 * @num: IRQ number index
53 int platform_get_irq(struct platform_device *dev, unsigned int num)
55 struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
57 return r ? r->start : 0;
61 * platform_get_resource_byname - get a resource for a device by name
62 * @dev: platform device
63 * @type: resource type
64 * @name: resource name
67 platform_get_resource_byname(struct platform_device *dev, unsigned int type,
72 for (i = 0; i < dev->num_resources; i++) {
73 struct resource *r = &dev->resource[i];
75 if ((r->flags & (IORESOURCE_IO|IORESOURCE_MEM|
76 IORESOURCE_IRQ|IORESOURCE_DMA)) == type)
77 if (!strcmp(r->name, name))
84 * platform_get_irq - get an IRQ for a device
85 * @dev: platform device
88 int platform_get_irq_byname(struct platform_device *dev, char *name)
90 struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
92 return r ? r->start : 0;
96 * platform_add_devices - add a numbers of platform devices
97 * @devs: array of platform devices to add
98 * @num: number of platform devices in array
100 int platform_add_devices(struct platform_device **devs, int num)
104 for (i = 0; i < num; i++) {
105 ret = platform_device_register(devs[i]);
108 platform_device_unregister(devs[i]);
117 * platform_device_register - add a platform-level device
118 * @pdev: platform device we're adding
121 int platform_device_register(struct platform_device * pdev)
128 if (!pdev->dev.parent)
129 pdev->dev.parent = &platform_bus;
131 pdev->dev.bus = &platform_bus_type;
134 snprintf(pdev->dev.bus_id, BUS_ID_SIZE, "%s.%u", pdev->name, pdev->id);
136 strlcpy(pdev->dev.bus_id, pdev->name, BUS_ID_SIZE);
138 for (i = 0; i < pdev->num_resources; i++) {
139 struct resource *p, *r = &pdev->resource[i];
142 r->name = pdev->dev.bus_id;
146 if (r->flags & IORESOURCE_MEM)
148 else if (r->flags & IORESOURCE_IO)
149 p = &ioport_resource;
152 if (p && request_resource(p, r)) {
154 "%s: failed to claim resource %d\n",
155 pdev->dev.bus_id, i);
161 pr_debug("Registering platform device '%s'. Parent at %s\n",
162 pdev->dev.bus_id, pdev->dev.parent->bus_id);
164 ret = device_register(&pdev->dev);
170 if (pdev->resource[i].flags & (IORESOURCE_MEM|IORESOURCE_IO))
171 release_resource(&pdev->resource[i]);
176 * platform_device_unregister - remove a platform-level device
177 * @pdev: platform device we're removing
179 * Note that this function will also release all memory- and port-based
180 * resources owned by the device (@dev->resource).
182 void platform_device_unregister(struct platform_device * pdev)
187 for (i = 0; i < pdev->num_resources; i++) {
188 struct resource *r = &pdev->resource[i];
189 if (r->flags & (IORESOURCE_MEM|IORESOURCE_IO))
193 device_unregister(&pdev->dev);
197 struct platform_object {
198 struct platform_device pdev;
199 struct resource resources[0];
202 static void platform_device_release_simple(struct device *dev)
204 struct platform_device *pdev = to_platform_device(dev);
206 kfree(container_of(pdev, struct platform_object, pdev));
210 * platform_device_register_simple
211 * @name: base name of the device we're adding
213 * @res: set of resources that needs to be allocated for the device
214 * @num: number of resources
216 * This function creates a simple platform device that requires minimal
217 * resource and memory management. Canned release function freeing
218 * memory allocated for the device allows drivers using such devices
219 * to be unloaded iwithout waiting for the last reference to the device
222 struct platform_device *platform_device_register_simple(char *name, unsigned int id,
223 struct resource *res, unsigned int num)
225 struct platform_object *pobj;
228 pobj = kzalloc(sizeof(*pobj) + sizeof(struct resource) * num, GFP_KERNEL);
234 pobj->pdev.name = name;
236 pobj->pdev.dev.release = platform_device_release_simple;
239 memcpy(pobj->resources, res, sizeof(struct resource) * num);
240 pobj->pdev.resource = pobj->resources;
241 pobj->pdev.num_resources = num;
244 retval = platform_device_register(&pobj->pdev);
252 return ERR_PTR(retval);
257 * platform_match - bind platform device to platform driver.
261 * Platform device IDs are assumed to be encoded like this:
262 * "<name><instance>", where <name> is a short description of the
263 * type of device, like "pci" or "floppy", and <instance> is the
264 * enumerated instance of the device, like '0' or '42'.
265 * Driver IDs are simply "<name>".
266 * So, extract the <name> from the platform_device structure,
267 * and compare it against the name of the driver. Return whether
271 static int platform_match(struct device * dev, struct device_driver * drv)
273 struct platform_device *pdev = container_of(dev, struct platform_device, dev);
275 return (strncmp(pdev->name, drv->name, BUS_ID_SIZE) == 0);
278 static int platform_suspend(struct device * dev, pm_message_t state)
282 if (dev->driver && dev->driver->suspend) {
283 ret = dev->driver->suspend(dev, state, SUSPEND_DISABLE);
285 ret = dev->driver->suspend(dev, state, SUSPEND_SAVE_STATE);
287 ret = dev->driver->suspend(dev, state, SUSPEND_POWER_DOWN);
292 static int platform_resume(struct device * dev)
296 if (dev->driver && dev->driver->resume) {
297 ret = dev->driver->resume(dev, RESUME_POWER_ON);
299 ret = dev->driver->resume(dev, RESUME_RESTORE_STATE);
301 ret = dev->driver->resume(dev, RESUME_ENABLE);
306 struct bus_type platform_bus_type = {
308 .match = platform_match,
309 .suspend = platform_suspend,
310 .resume = platform_resume,
313 int __init platform_bus_init(void)
315 device_register(&platform_bus);
316 return bus_register(&platform_bus_type);
319 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
320 u64 dma_get_required_mask(struct device *dev)
322 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
323 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
326 if (!high_totalram) {
327 /* convert to mask just covering totalram */
328 low_totalram = (1 << (fls(low_totalram) - 1));
329 low_totalram += low_totalram - 1;
332 high_totalram = (1 << (fls(high_totalram) - 1));
333 high_totalram += high_totalram - 1;
334 mask = (((u64)high_totalram) << 32) + 0xffffffff;
336 return mask & *dev->dma_mask;
338 EXPORT_SYMBOL_GPL(dma_get_required_mask);
341 EXPORT_SYMBOL_GPL(platform_bus);
342 EXPORT_SYMBOL_GPL(platform_bus_type);
343 EXPORT_SYMBOL_GPL(platform_add_devices);
344 EXPORT_SYMBOL_GPL(platform_device_register);
345 EXPORT_SYMBOL_GPL(platform_device_register_simple);
346 EXPORT_SYMBOL_GPL(platform_device_unregister);
347 EXPORT_SYMBOL_GPL(platform_get_irq);
348 EXPORT_SYMBOL_GPL(platform_get_resource);
349 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
350 EXPORT_SYMBOL_GPL(platform_get_resource_byname);