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_add_devices - add a numbers of platform devices
62 * @devs: array of platform devices to add
63 * @num: number of platform devices in array
65 int platform_add_devices(struct platform_device **devs, int num)
69 for (i = 0; i < num; i++) {
70 ret = platform_device_register(devs[i]);
73 platform_device_unregister(devs[i]);
82 * platform_device_register - add a platform-level device
83 * @dev: platform device we're adding
86 int platform_device_register(struct platform_device * pdev)
93 if (!pdev->dev.parent)
94 pdev->dev.parent = &platform_bus;
96 pdev->dev.bus = &platform_bus_type;
99 snprintf(pdev->dev.bus_id, BUS_ID_SIZE, "%s%u", pdev->name, pdev->id);
101 strlcpy(pdev->dev.bus_id, pdev->name, BUS_ID_SIZE);
103 for (i = 0; i < pdev->num_resources; i++) {
104 struct resource *p, *r = &pdev->resource[i];
106 r->name = pdev->dev.bus_id;
109 if (r->flags & IORESOURCE_MEM)
111 else if (r->flags & IORESOURCE_IO)
112 p = &ioport_resource;
114 if (p && request_resource(p, r)) {
116 "%s: failed to claim resource %d\n",
117 pdev->dev.bus_id, i);
123 pr_debug("Registering platform device '%s'. Parent at %s\n",
124 pdev->dev.bus_id, pdev->dev.parent->bus_id);
126 ret = device_register(&pdev->dev);
132 if (pdev->resource[i].flags & (IORESOURCE_MEM|IORESOURCE_IO))
133 release_resource(&pdev->resource[i]);
138 * platform_device_unregister - remove a platform-level device
139 * @dev: platform device we're removing
141 * Note that this function will also release all memory- and port-based
142 * resources owned by the device (@dev->resource).
144 void platform_device_unregister(struct platform_device * pdev)
149 for (i = 0; i < pdev->num_resources; i++) {
150 struct resource *r = &pdev->resource[i];
151 if (r->flags & (IORESOURCE_MEM|IORESOURCE_IO))
155 device_unregister(&pdev->dev);
159 struct platform_object {
160 struct platform_device pdev;
161 struct resource resources[0];
164 static void platform_device_release_simple(struct device *dev)
166 struct platform_device *pdev = to_platform_device(dev);
168 kfree(container_of(pdev, struct platform_object, pdev));
172 * platform_device_register_simple
173 * @name: base name of the device we're adding
175 * @res: set of resources that needs to be allocated for the device
176 * @num: number of resources
178 * This function creates a simple platform device that requires minimal
179 * resource and memory management. Canned release function freeing
180 * memory allocated for the device allows drivers using such devices
181 * to be unloaded iwithout waiting for the last reference to the device
184 struct platform_device *platform_device_register_simple(char *name, unsigned int id,
185 struct resource *res, unsigned int num)
187 struct platform_object *pobj;
190 pobj = kmalloc(sizeof(struct platform_object) + sizeof(struct resource) * num, GFP_KERNEL);
196 memset(pobj, 0, sizeof(*pobj));
197 pobj->pdev.name = name;
199 pobj->pdev.dev.release = platform_device_release_simple;
202 memcpy(pobj->resources, res, sizeof(struct resource) * num);
203 pobj->pdev.resource = pobj->resources;
204 pobj->pdev.num_resources = num;
207 retval = platform_device_register(&pobj->pdev);
215 return ERR_PTR(retval);
220 * platform_match - bind platform device to platform driver.
224 * Platform device IDs are assumed to be encoded like this:
225 * "<name><instance>", where <name> is a short description of the
226 * type of device, like "pci" or "floppy", and <instance> is the
227 * enumerated instance of the device, like '0' or '42'.
228 * Driver IDs are simply "<name>".
229 * So, extract the <name> from the platform_device structure,
230 * and compare it against the name of the driver. Return whether
234 static int platform_match(struct device * dev, struct device_driver * drv)
236 struct platform_device *pdev = container_of(dev, struct platform_device, dev);
238 return (strncmp(pdev->name, drv->name, BUS_ID_SIZE) == 0);
241 static int platform_suspend(struct device * dev, u32 state)
245 if (dev->driver && dev->driver->suspend) {
246 ret = dev->driver->suspend(dev, state, SUSPEND_DISABLE);
248 ret = dev->driver->suspend(dev, state, SUSPEND_SAVE_STATE);
250 ret = dev->driver->suspend(dev, state, SUSPEND_POWER_DOWN);
255 static int platform_resume(struct device * dev)
259 if (dev->driver && dev->driver->resume) {
260 ret = dev->driver->resume(dev, RESUME_POWER_ON);
262 ret = dev->driver->resume(dev, RESUME_RESTORE_STATE);
264 ret = dev->driver->resume(dev, RESUME_ENABLE);
269 struct bus_type platform_bus_type = {
271 .match = platform_match,
272 .suspend = platform_suspend,
273 .resume = platform_resume,
276 int __init platform_bus_init(void)
278 device_register(&platform_bus);
279 return bus_register(&platform_bus_type);
282 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
283 u64 dma_get_required_mask(struct device *dev)
285 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
286 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
289 if (!high_totalram) {
290 /* convert to mask just covering totalram */
291 low_totalram = (1 << (fls(low_totalram) - 1));
292 low_totalram += low_totalram - 1;
295 high_totalram = (1 << (fls(high_totalram) - 1));
296 high_totalram += high_totalram - 1;
297 mask = (((u64)high_totalram) << 32) + 0xffffffff;
299 return mask & *dev->dma_mask;
301 EXPORT_SYMBOL(dma_get_required_mask);
304 EXPORT_SYMBOL(platform_bus);
305 EXPORT_SYMBOL(platform_bus_type);
306 EXPORT_SYMBOL(platform_device_register);
307 EXPORT_SYMBOL(platform_device_register_simple);
308 EXPORT_SYMBOL(platform_device_unregister);
309 EXPORT_SYMBOL(platform_get_irq);
310 EXPORT_SYMBOL(platform_get_resource);