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/string.h>
14 #include <linux/platform_device.h>
15 #include <linux/of_device.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/bootmem.h>
20 #include <linux/err.h>
21 #include <linux/slab.h>
22 #include <linux/pm_runtime.h>
26 #define to_platform_driver(drv) (container_of((drv), struct platform_driver, \
29 struct device platform_bus = {
30 .init_name = "platform",
32 EXPORT_SYMBOL_GPL(platform_bus);
35 * platform_get_resource - get a resource for a device
36 * @dev: platform device
37 * @type: resource type
38 * @num: resource index
40 struct resource *platform_get_resource(struct platform_device *dev,
41 unsigned int type, unsigned int num)
45 for (i = 0; i < dev->num_resources; i++) {
46 struct resource *r = &dev->resource[i];
48 if (type == resource_type(r) && num-- == 0)
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
74 struct resource *platform_get_resource_byname(struct platform_device *dev,
80 for (i = 0; i < dev->num_resources; i++) {
81 struct resource *r = &dev->resource[i];
83 if (type == resource_type(r) && !strcmp(r->name, name))
88 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
91 * platform_get_irq - get an IRQ for a device
92 * @dev: platform device
95 int platform_get_irq_byname(struct platform_device *dev, const char *name)
97 struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
100 return r ? r->start : -ENXIO;
102 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
105 * platform_add_devices - add a numbers of platform devices
106 * @devs: array of platform devices to add
107 * @num: number of platform devices in array
109 int platform_add_devices(struct platform_device **devs, int num)
113 for (i = 0; i < num; i++) {
114 ret = platform_device_register(devs[i]);
117 platform_device_unregister(devs[i]);
124 EXPORT_SYMBOL_GPL(platform_add_devices);
126 struct platform_object {
127 struct platform_device pdev;
132 * platform_device_put - destroy a platform device
133 * @pdev: platform device to free
135 * Free all memory associated with a platform device. This function must
136 * _only_ be externally called in error cases. All other usage is a bug.
138 void platform_device_put(struct platform_device *pdev)
141 put_device(&pdev->dev);
143 EXPORT_SYMBOL_GPL(platform_device_put);
145 static void platform_device_release(struct device *dev)
147 struct platform_object *pa = container_of(dev, struct platform_object,
150 kfree(pa->pdev.dev.platform_data);
151 kfree(pa->pdev.resource);
156 * platform_device_alloc - create a platform device
157 * @name: base name of the device we're adding
160 * Create a platform device object which can have other objects attached
161 * to it, and which will have attached objects freed when it is released.
163 struct platform_device *platform_device_alloc(const char *name, int id)
165 struct platform_object *pa;
167 pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
169 strcpy(pa->name, name);
170 pa->pdev.name = pa->name;
172 device_initialize(&pa->pdev.dev);
173 pa->pdev.dev.release = platform_device_release;
176 return pa ? &pa->pdev : NULL;
178 EXPORT_SYMBOL_GPL(platform_device_alloc);
181 * platform_device_add_resources - add resources to a platform device
182 * @pdev: platform device allocated by platform_device_alloc to add resources to
183 * @res: set of resources that needs to be allocated for the device
184 * @num: number of resources
186 * Add a copy of the resources to the platform device. The memory
187 * associated with the resources will be freed when the platform device is
190 int platform_device_add_resources(struct platform_device *pdev,
191 const struct resource *res, unsigned int num)
195 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
198 pdev->num_resources = num;
203 EXPORT_SYMBOL_GPL(platform_device_add_resources);
206 * platform_device_add_data - add platform-specific data to a platform device
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
212 * platform_data pointer. The memory associated with the platform data
213 * will be freed when the platform device is released.
215 int platform_device_add_data(struct platform_device *pdev, const void *data,
218 void *d = kmemdup(data, size, GFP_KERNEL);
221 pdev->dev.platform_data = d;
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 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
250 dev_set_name(&pdev->dev, "%s", pdev->name);
252 for (i = 0; i < pdev->num_resources; i++) {
253 struct resource *p, *r = &pdev->resource[i];
256 r->name = dev_name(&pdev->dev);
260 if (resource_type(r) == IORESOURCE_MEM)
262 else if (resource_type(r) == IORESOURCE_IO)
263 p = &ioport_resource;
266 if (p && insert_resource(p, r)) {
268 "%s: failed to claim resource %d\n",
269 dev_name(&pdev->dev), i);
275 pr_debug("Registering platform device '%s'. Parent at %s\n",
276 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
278 ret = device_add(&pdev->dev);
284 struct resource *r = &pdev->resource[i];
285 unsigned long type = resource_type(r);
287 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
293 EXPORT_SYMBOL_GPL(platform_device_add);
296 * platform_device_del - remove a platform-level device
297 * @pdev: platform device we're removing
299 * Note that this function will also release all memory- and port-based
300 * resources owned by the device (@dev->resource). This function must
301 * _only_ be externally called in error cases. All other usage is a bug.
303 void platform_device_del(struct platform_device *pdev)
308 device_del(&pdev->dev);
310 for (i = 0; i < pdev->num_resources; i++) {
311 struct resource *r = &pdev->resource[i];
312 unsigned long type = resource_type(r);
314 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
319 EXPORT_SYMBOL_GPL(platform_device_del);
322 * platform_device_register - add a platform-level device
323 * @pdev: platform device we're adding
325 int platform_device_register(struct platform_device *pdev)
327 device_initialize(&pdev->dev);
328 return platform_device_add(pdev);
330 EXPORT_SYMBOL_GPL(platform_device_register);
333 * platform_device_unregister - unregister a platform-level device
334 * @pdev: platform device we're unregistering
336 * Unregistration is done in 2 steps. First we release all resources
337 * and remove it from the subsystem, then we drop reference count by
338 * calling platform_device_put().
340 void platform_device_unregister(struct platform_device *pdev)
342 platform_device_del(pdev);
343 platform_device_put(pdev);
345 EXPORT_SYMBOL_GPL(platform_device_unregister);
348 * platform_device_register_resndata - add a platform-level device with
349 * resources and platform-specific data
351 * @parent: parent device for the device we're adding
352 * @name: base name of the device we're adding
354 * @res: set of resources that needs to be allocated for the device
355 * @num: number of resources
356 * @data: platform specific data for this platform device
357 * @size: size of platform specific data
359 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
361 struct platform_device *__init_or_module platform_device_register_resndata(
362 struct device *parent,
363 const char *name, int id,
364 const struct resource *res, unsigned int num,
365 const void *data, size_t size)
368 struct platform_device *pdev;
370 pdev = platform_device_alloc(name, id);
374 pdev->dev.parent = parent;
377 ret = platform_device_add_resources(pdev, res, num);
383 ret = platform_device_add_data(pdev, data, size);
388 ret = platform_device_add(pdev);
391 platform_device_put(pdev);
397 EXPORT_SYMBOL_GPL(platform_device_register_resndata);
399 static int platform_drv_probe(struct device *_dev)
401 struct platform_driver *drv = to_platform_driver(_dev->driver);
402 struct platform_device *dev = to_platform_device(_dev);
404 return drv->probe(dev);
407 static int platform_drv_probe_fail(struct device *_dev)
412 static int platform_drv_remove(struct device *_dev)
414 struct platform_driver *drv = to_platform_driver(_dev->driver);
415 struct platform_device *dev = to_platform_device(_dev);
417 return drv->remove(dev);
420 static void platform_drv_shutdown(struct device *_dev)
422 struct platform_driver *drv = to_platform_driver(_dev->driver);
423 struct platform_device *dev = to_platform_device(_dev);
429 * platform_driver_register - register a driver for platform-level devices
430 * @drv: platform driver structure
432 int platform_driver_register(struct platform_driver *drv)
434 drv->driver.bus = &platform_bus_type;
436 drv->driver.probe = platform_drv_probe;
438 drv->driver.remove = platform_drv_remove;
440 drv->driver.shutdown = platform_drv_shutdown;
442 return driver_register(&drv->driver);
444 EXPORT_SYMBOL_GPL(platform_driver_register);
447 * platform_driver_unregister - unregister a driver for platform-level devices
448 * @drv: platform driver structure
450 void platform_driver_unregister(struct platform_driver *drv)
452 driver_unregister(&drv->driver);
454 EXPORT_SYMBOL_GPL(platform_driver_unregister);
457 * platform_driver_probe - register driver for non-hotpluggable device
458 * @drv: platform driver structure
459 * @probe: the driver probe routine, probably from an __init section
461 * Use this instead of platform_driver_register() when you know the device
462 * is not hotpluggable and has already been registered, and you want to
463 * remove its run-once probe() infrastructure from memory after the driver
464 * has bound to the device.
466 * One typical use for this would be with drivers for controllers integrated
467 * into system-on-chip processors, where the controller devices have been
468 * configured as part of board setup.
470 * Returns zero if the driver registered and bound to a device, else returns
471 * a negative error code and with the driver not registered.
473 int __init_or_module platform_driver_probe(struct platform_driver *drv,
474 int (*probe)(struct platform_device *))
478 /* make sure driver won't have bind/unbind attributes */
479 drv->driver.suppress_bind_attrs = true;
481 /* temporary section violation during probe() */
483 retval = code = platform_driver_register(drv);
486 * Fixup that section violation, being paranoid about code scanning
487 * the list of drivers in order to probe new devices. Check to see
488 * if the probe was successful, and make sure any forced probes of
491 spin_lock(&platform_bus_type.p->klist_drivers.k_lock);
493 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
495 drv->driver.probe = platform_drv_probe_fail;
496 spin_unlock(&platform_bus_type.p->klist_drivers.k_lock);
499 platform_driver_unregister(drv);
502 EXPORT_SYMBOL_GPL(platform_driver_probe);
505 * platform_create_bundle - register driver and create corresponding device
506 * @driver: platform driver structure
507 * @probe: the driver probe routine, probably from an __init section
508 * @res: set of resources that needs to be allocated for the device
509 * @n_res: number of resources
510 * @data: platform specific data for this platform device
511 * @size: size of platform specific data
513 * Use this in legacy-style modules that probe hardware directly and
514 * register a single platform device and corresponding platform driver.
516 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
518 struct platform_device * __init_or_module platform_create_bundle(
519 struct platform_driver *driver,
520 int (*probe)(struct platform_device *),
521 struct resource *res, unsigned int n_res,
522 const void *data, size_t size)
524 struct platform_device *pdev;
527 pdev = platform_device_alloc(driver->driver.name, -1);
534 error = platform_device_add_resources(pdev, res, n_res);
540 error = platform_device_add_data(pdev, data, size);
545 error = platform_device_add(pdev);
549 error = platform_driver_probe(driver, probe);
556 platform_device_del(pdev);
558 platform_device_put(pdev);
560 return ERR_PTR(error);
562 EXPORT_SYMBOL_GPL(platform_create_bundle);
564 /* modalias support enables more hands-off userspace setup:
565 * (a) environment variable lets new-style hotplug events work once system is
566 * fully running: "modprobe $MODALIAS"
567 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
568 * mishandled before system is fully running: "modprobe $(cat modalias)"
570 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
573 struct platform_device *pdev = to_platform_device(dev);
574 int len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
576 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
579 static struct device_attribute platform_dev_attrs[] = {
584 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
586 struct platform_device *pdev = to_platform_device(dev);
589 /* Some devices have extra OF data and an OF-style MODALIAS */
590 rc = of_device_uevent(dev,env);
594 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
595 (pdev->id_entry) ? pdev->id_entry->name : pdev->name);
599 static const struct platform_device_id *platform_match_id(
600 const struct platform_device_id *id,
601 struct platform_device *pdev)
603 while (id->name[0]) {
604 if (strcmp(pdev->name, id->name) == 0) {
614 * platform_match - bind platform device to platform driver.
618 * Platform device IDs are assumed to be encoded like this:
619 * "<name><instance>", where <name> is a short description of the type of
620 * device, like "pci" or "floppy", and <instance> is the enumerated
621 * instance of the device, like '0' or '42'. Driver IDs are simply
622 * "<name>". So, extract the <name> from the platform_device structure,
623 * and compare it against the name of the driver. Return whether they match
626 static int platform_match(struct device *dev, struct device_driver *drv)
628 struct platform_device *pdev = to_platform_device(dev);
629 struct platform_driver *pdrv = to_platform_driver(drv);
631 /* Attempt an OF style match first */
632 if (of_driver_match_device(dev, drv))
635 /* Then try to match against the id table */
637 return platform_match_id(pdrv->id_table, pdev) != NULL;
639 /* fall-back to driver name match */
640 return (strcmp(pdev->name, drv->name) == 0);
643 #ifdef CONFIG_PM_SLEEP
645 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
647 struct platform_driver *pdrv = to_platform_driver(dev->driver);
648 struct platform_device *pdev = to_platform_device(dev);
651 if (dev->driver && pdrv->suspend)
652 ret = pdrv->suspend(pdev, mesg);
657 static int platform_legacy_resume(struct device *dev)
659 struct platform_driver *pdrv = to_platform_driver(dev->driver);
660 struct platform_device *pdev = to_platform_device(dev);
663 if (dev->driver && pdrv->resume)
664 ret = pdrv->resume(pdev);
669 static int platform_pm_prepare(struct device *dev)
671 struct device_driver *drv = dev->driver;
674 if (drv && drv->pm && drv->pm->prepare)
675 ret = drv->pm->prepare(dev);
680 static void platform_pm_complete(struct device *dev)
682 struct device_driver *drv = dev->driver;
684 if (drv && drv->pm && drv->pm->complete)
685 drv->pm->complete(dev);
688 #else /* !CONFIG_PM_SLEEP */
690 #define platform_pm_prepare NULL
691 #define platform_pm_complete NULL
693 #endif /* !CONFIG_PM_SLEEP */
695 #ifdef CONFIG_SUSPEND
697 int __weak platform_pm_suspend(struct device *dev)
699 struct device_driver *drv = dev->driver;
706 if (drv->pm->suspend)
707 ret = drv->pm->suspend(dev);
709 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
715 int __weak platform_pm_suspend_noirq(struct device *dev)
717 struct device_driver *drv = dev->driver;
724 if (drv->pm->suspend_noirq)
725 ret = drv->pm->suspend_noirq(dev);
731 int __weak platform_pm_resume(struct device *dev)
733 struct device_driver *drv = dev->driver;
741 ret = drv->pm->resume(dev);
743 ret = platform_legacy_resume(dev);
749 int __weak platform_pm_resume_noirq(struct device *dev)
751 struct device_driver *drv = dev->driver;
758 if (drv->pm->resume_noirq)
759 ret = drv->pm->resume_noirq(dev);
765 #else /* !CONFIG_SUSPEND */
767 #define platform_pm_suspend NULL
768 #define platform_pm_resume NULL
769 #define platform_pm_suspend_noirq NULL
770 #define platform_pm_resume_noirq NULL
772 #endif /* !CONFIG_SUSPEND */
774 #ifdef CONFIG_HIBERNATION
776 static int platform_pm_freeze(struct device *dev)
778 struct device_driver *drv = dev->driver;
786 ret = drv->pm->freeze(dev);
788 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
794 static int platform_pm_freeze_noirq(struct device *dev)
796 struct device_driver *drv = dev->driver;
803 if (drv->pm->freeze_noirq)
804 ret = drv->pm->freeze_noirq(dev);
810 static int platform_pm_thaw(struct device *dev)
812 struct device_driver *drv = dev->driver;
820 ret = drv->pm->thaw(dev);
822 ret = platform_legacy_resume(dev);
828 static int platform_pm_thaw_noirq(struct device *dev)
830 struct device_driver *drv = dev->driver;
837 if (drv->pm->thaw_noirq)
838 ret = drv->pm->thaw_noirq(dev);
844 static int platform_pm_poweroff(struct device *dev)
846 struct device_driver *drv = dev->driver;
853 if (drv->pm->poweroff)
854 ret = drv->pm->poweroff(dev);
856 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
862 static int platform_pm_poweroff_noirq(struct device *dev)
864 struct device_driver *drv = dev->driver;
871 if (drv->pm->poweroff_noirq)
872 ret = drv->pm->poweroff_noirq(dev);
878 static int platform_pm_restore(struct device *dev)
880 struct device_driver *drv = dev->driver;
887 if (drv->pm->restore)
888 ret = drv->pm->restore(dev);
890 ret = platform_legacy_resume(dev);
896 static int platform_pm_restore_noirq(struct device *dev)
898 struct device_driver *drv = dev->driver;
905 if (drv->pm->restore_noirq)
906 ret = drv->pm->restore_noirq(dev);
912 #else /* !CONFIG_HIBERNATION */
914 #define platform_pm_freeze NULL
915 #define platform_pm_thaw NULL
916 #define platform_pm_poweroff NULL
917 #define platform_pm_restore NULL
918 #define platform_pm_freeze_noirq NULL
919 #define platform_pm_thaw_noirq NULL
920 #define platform_pm_poweroff_noirq NULL
921 #define platform_pm_restore_noirq NULL
923 #endif /* !CONFIG_HIBERNATION */
925 #ifdef CONFIG_PM_RUNTIME
927 int __weak platform_pm_runtime_suspend(struct device *dev)
929 return pm_generic_runtime_suspend(dev);
932 int __weak platform_pm_runtime_resume(struct device *dev)
934 return pm_generic_runtime_resume(dev);
937 int __weak platform_pm_runtime_idle(struct device *dev)
939 return pm_generic_runtime_idle(dev);
942 #else /* !CONFIG_PM_RUNTIME */
944 #define platform_pm_runtime_suspend NULL
945 #define platform_pm_runtime_resume NULL
946 #define platform_pm_runtime_idle NULL
948 #endif /* !CONFIG_PM_RUNTIME */
950 static const struct dev_pm_ops platform_dev_pm_ops = {
951 .prepare = platform_pm_prepare,
952 .complete = platform_pm_complete,
953 .suspend = platform_pm_suspend,
954 .resume = platform_pm_resume,
955 .freeze = platform_pm_freeze,
956 .thaw = platform_pm_thaw,
957 .poweroff = platform_pm_poweroff,
958 .restore = platform_pm_restore,
959 .suspend_noirq = platform_pm_suspend_noirq,
960 .resume_noirq = platform_pm_resume_noirq,
961 .freeze_noirq = platform_pm_freeze_noirq,
962 .thaw_noirq = platform_pm_thaw_noirq,
963 .poweroff_noirq = platform_pm_poweroff_noirq,
964 .restore_noirq = platform_pm_restore_noirq,
965 .runtime_suspend = platform_pm_runtime_suspend,
966 .runtime_resume = platform_pm_runtime_resume,
967 .runtime_idle = platform_pm_runtime_idle,
970 struct bus_type platform_bus_type = {
972 .dev_attrs = platform_dev_attrs,
973 .match = platform_match,
974 .uevent = platform_uevent,
975 .pm = &platform_dev_pm_ops,
977 EXPORT_SYMBOL_GPL(platform_bus_type);
979 int __init platform_bus_init(void)
983 early_platform_cleanup();
985 error = device_register(&platform_bus);
988 error = bus_register(&platform_bus_type);
990 device_unregister(&platform_bus);
994 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
995 u64 dma_get_required_mask(struct device *dev)
997 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
998 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1001 if (!high_totalram) {
1002 /* convert to mask just covering totalram */
1003 low_totalram = (1 << (fls(low_totalram) - 1));
1004 low_totalram += low_totalram - 1;
1005 mask = low_totalram;
1007 high_totalram = (1 << (fls(high_totalram) - 1));
1008 high_totalram += high_totalram - 1;
1009 mask = (((u64)high_totalram) << 32) + 0xffffffff;
1013 EXPORT_SYMBOL_GPL(dma_get_required_mask);
1016 static __initdata LIST_HEAD(early_platform_driver_list);
1017 static __initdata LIST_HEAD(early_platform_device_list);
1020 * early_platform_driver_register - register early platform driver
1021 * @epdrv: early_platform driver structure
1022 * @buf: string passed from early_param()
1024 * Helper function for early_platform_init() / early_platform_init_buffer()
1026 int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1032 /* Simply add the driver to the end of the global list.
1033 * Drivers will by default be put on the list in compiled-in order.
1035 if (!epdrv->list.next) {
1036 INIT_LIST_HEAD(&epdrv->list);
1037 list_add_tail(&epdrv->list, &early_platform_driver_list);
1040 /* If the user has specified device then make sure the driver
1041 * gets prioritized. The driver of the last device specified on
1042 * command line will be put first on the list.
1044 n = strlen(epdrv->pdrv->driver.name);
1045 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1046 list_move(&epdrv->list, &early_platform_driver_list);
1048 /* Allow passing parameters after device name */
1049 if (buf[n] == '\0' || buf[n] == ',')
1050 epdrv->requested_id = -1;
1052 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1055 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1056 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1059 n += strcspn(&buf[n + 1], ",") + 1;
1065 if (epdrv->bufsize) {
1066 memcpy(epdrv->buffer, &buf[n],
1067 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1068 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1076 * early_platform_add_devices - adds a number of early platform devices
1077 * @devs: array of early platform devices to add
1078 * @num: number of early platform devices in array
1080 * Used by early architecture code to register early platform devices and
1081 * their platform data.
1083 void __init early_platform_add_devices(struct platform_device **devs, int num)
1088 /* simply add the devices to list */
1089 for (i = 0; i < num; i++) {
1090 dev = &devs[i]->dev;
1092 if (!dev->devres_head.next) {
1093 INIT_LIST_HEAD(&dev->devres_head);
1094 list_add_tail(&dev->devres_head,
1095 &early_platform_device_list);
1101 * early_platform_driver_register_all - register early platform drivers
1102 * @class_str: string to identify early platform driver class
1104 * Used by architecture code to register all early platform drivers
1105 * for a certain class. If omitted then only early platform drivers
1106 * with matching kernel command line class parameters will be registered.
1108 void __init early_platform_driver_register_all(char *class_str)
1110 /* The "class_str" parameter may or may not be present on the kernel
1111 * command line. If it is present then there may be more than one
1112 * matching parameter.
1114 * Since we register our early platform drivers using early_param()
1115 * we need to make sure that they also get registered in the case
1116 * when the parameter is missing from the kernel command line.
1118 * We use parse_early_options() to make sure the early_param() gets
1119 * called at least once. The early_param() may be called more than
1120 * once since the name of the preferred device may be specified on
1121 * the kernel command line. early_platform_driver_register() handles
1124 parse_early_options(class_str);
1128 * early_platform_match - find early platform device matching driver
1129 * @epdrv: early platform driver structure
1130 * @id: id to match against
1132 static __init struct platform_device *
1133 early_platform_match(struct early_platform_driver *epdrv, int id)
1135 struct platform_device *pd;
1137 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1138 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1146 * early_platform_left - check if early platform driver has matching devices
1147 * @epdrv: early platform driver structure
1148 * @id: return true if id or above exists
1150 static __init int early_platform_left(struct early_platform_driver *epdrv,
1153 struct platform_device *pd;
1155 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1156 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1164 * early_platform_driver_probe_id - probe drivers matching class_str and id
1165 * @class_str: string to identify early platform driver class
1166 * @id: id to match against
1167 * @nr_probe: number of platform devices to successfully probe before exiting
1169 static int __init early_platform_driver_probe_id(char *class_str,
1173 struct early_platform_driver *epdrv;
1174 struct platform_device *match;
1179 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1180 /* only use drivers matching our class_str */
1181 if (strcmp(class_str, epdrv->class_str))
1185 match_id = epdrv->requested_id;
1190 left += early_platform_left(epdrv, id);
1192 /* skip requested id */
1193 switch (epdrv->requested_id) {
1194 case EARLY_PLATFORM_ID_ERROR:
1195 case EARLY_PLATFORM_ID_UNSET:
1198 if (epdrv->requested_id == id)
1199 match_id = EARLY_PLATFORM_ID_UNSET;
1204 case EARLY_PLATFORM_ID_ERROR:
1205 pr_warning("%s: unable to parse %s parameter\n",
1206 class_str, epdrv->pdrv->driver.name);
1208 case EARLY_PLATFORM_ID_UNSET:
1212 match = early_platform_match(epdrv, match_id);
1217 * Set up a sensible init_name to enable
1218 * dev_name() and others to be used before the
1219 * rest of the driver core is initialized.
1221 if (!match->dev.init_name && slab_is_available()) {
1222 if (match->id != -1)
1223 match->dev.init_name =
1224 kasprintf(GFP_KERNEL, "%s.%d",
1228 match->dev.init_name =
1229 kasprintf(GFP_KERNEL, "%s",
1232 if (!match->dev.init_name)
1236 if (epdrv->pdrv->probe(match))
1237 pr_warning("%s: unable to probe %s early.\n",
1238 class_str, match->name);
1254 * early_platform_driver_probe - probe a class of registered drivers
1255 * @class_str: string to identify early platform driver class
1256 * @nr_probe: number of platform devices to successfully probe before exiting
1257 * @user_only: only probe user specified early platform devices
1259 * Used by architecture code to probe registered early platform drivers
1260 * within a certain class. For probe to happen a registered early platform
1261 * device matching a registered early platform driver is needed.
1263 int __init early_platform_driver_probe(char *class_str,
1270 for (i = -2; n < nr_probe; i++) {
1271 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1286 * early_platform_cleanup - clean up early platform code
1288 void __init early_platform_cleanup(void)
1290 struct platform_device *pd, *pd2;
1292 /* clean up the devres list used to chain devices */
1293 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1295 list_del(&pd->dev.devres_head);
1296 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));