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, \
26 struct device platform_bus = {
27 .init_name = "platform",
29 EXPORT_SYMBOL_GPL(platform_bus);
32 * platform_get_resource - get a resource for a device
33 * @dev: platform device
34 * @type: resource type
35 * @num: resource index
37 struct resource *platform_get_resource(struct platform_device *dev,
38 unsigned int type, unsigned int num)
42 for (i = 0; i < dev->num_resources; i++) {
43 struct resource *r = &dev->resource[i];
45 if (type == resource_type(r) && num-- == 0)
50 EXPORT_SYMBOL_GPL(platform_get_resource);
53 * platform_get_irq - get an IRQ for a device
54 * @dev: platform device
55 * @num: IRQ number index
57 int platform_get_irq(struct platform_device *dev, unsigned int num)
59 struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
61 return r ? r->start : -ENXIO;
63 EXPORT_SYMBOL_GPL(platform_get_irq);
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
71 struct resource *platform_get_resource_byname(struct platform_device *dev,
72 unsigned int type, char *name)
76 for (i = 0; i < dev->num_resources; i++) {
77 struct resource *r = &dev->resource[i];
79 if (type == resource_type(r) && !strcmp(r->name, name))
84 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
87 * platform_get_irq - get an IRQ for a device
88 * @dev: platform device
91 int platform_get_irq_byname(struct platform_device *dev, char *name)
93 struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
96 return r ? r->start : -ENXIO;
98 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
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
105 int platform_add_devices(struct platform_device **devs, int num)
109 for (i = 0; i < num; i++) {
110 ret = platform_device_register(devs[i]);
113 platform_device_unregister(devs[i]);
120 EXPORT_SYMBOL_GPL(platform_add_devices);
122 struct platform_object {
123 struct platform_device pdev;
128 * platform_device_put
129 * @pdev: platform device to free
131 * Free all memory associated with a platform device. This function must
132 * _only_ be externally called in error cases. All other usage is a bug.
134 void platform_device_put(struct platform_device *pdev)
137 put_device(&pdev->dev);
139 EXPORT_SYMBOL_GPL(platform_device_put);
141 static void platform_device_release(struct device *dev)
143 struct platform_object *pa = container_of(dev, struct platform_object,
146 kfree(pa->pdev.dev.platform_data);
147 kfree(pa->pdev.resource);
152 * platform_device_alloc
153 * @name: base name of the device we're adding
156 * Create a platform device object which can have other objects attached
157 * to it, and which will have attached objects freed when it is released.
159 struct platform_device *platform_device_alloc(const char *name, int id)
161 struct platform_object *pa;
163 pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
165 strcpy(pa->name, name);
166 pa->pdev.name = pa->name;
168 device_initialize(&pa->pdev.dev);
169 pa->pdev.dev.release = platform_device_release;
172 return pa ? &pa->pdev : NULL;
174 EXPORT_SYMBOL_GPL(platform_device_alloc);
177 * platform_device_add_resources
178 * @pdev: platform device allocated by platform_device_alloc to add resources to
179 * @res: set of resources that needs to be allocated for the device
180 * @num: number of resources
182 * Add a copy of the resources to the platform device. The memory
183 * associated with the resources will be freed when the platform device is
186 int platform_device_add_resources(struct platform_device *pdev,
187 struct resource *res, unsigned int num)
191 r = kmalloc(sizeof(struct resource) * num, GFP_KERNEL);
193 memcpy(r, res, sizeof(struct resource) * num);
195 pdev->num_resources = num;
197 return r ? 0 : -ENOMEM;
199 EXPORT_SYMBOL_GPL(platform_device_add_resources);
202 * platform_device_add_data
203 * @pdev: platform device allocated by platform_device_alloc to add resources to
204 * @data: platform specific data for this platform device
205 * @size: size of platform specific data
207 * Add a copy of platform specific data to the platform device's
208 * platform_data pointer. The memory associated with the platform data
209 * will be freed when the platform device is released.
211 int platform_device_add_data(struct platform_device *pdev, const void *data,
216 d = kmalloc(size, GFP_KERNEL);
218 memcpy(d, data, size);
219 pdev->dev.platform_data = d;
221 return d ? 0 : -ENOMEM;
223 EXPORT_SYMBOL_GPL(platform_device_add_data);
226 * platform_device_add - add a platform device to device hierarchy
227 * @pdev: platform device we're adding
229 * This is part 2 of platform_device_register(), though may be called
230 * separately _iff_ pdev was allocated by platform_device_alloc().
232 int platform_device_add(struct platform_device *pdev)
239 if (!pdev->dev.parent)
240 pdev->dev.parent = &platform_bus;
242 pdev->dev.bus = &platform_bus_type;
245 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
247 dev_set_name(&pdev->dev, pdev->name);
249 for (i = 0; i < pdev->num_resources; i++) {
250 struct resource *p, *r = &pdev->resource[i];
253 r->name = dev_name(&pdev->dev);
257 if (resource_type(r) == IORESOURCE_MEM)
259 else if (resource_type(r) == IORESOURCE_IO)
260 p = &ioport_resource;
263 if (p && insert_resource(p, r)) {
265 "%s: failed to claim resource %d\n",
266 dev_name(&pdev->dev), i);
272 pr_debug("Registering platform device '%s'. Parent at %s\n",
273 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
275 ret = device_add(&pdev->dev);
281 struct resource *r = &pdev->resource[i];
282 unsigned long type = resource_type(r);
284 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
290 EXPORT_SYMBOL_GPL(platform_device_add);
293 * platform_device_del - remove a platform-level device
294 * @pdev: platform device we're removing
296 * Note that this function will also release all memory- and port-based
297 * resources owned by the device (@dev->resource). This function must
298 * _only_ be externally called in error cases. All other usage is a bug.
300 void platform_device_del(struct platform_device *pdev)
305 device_del(&pdev->dev);
307 for (i = 0; i < pdev->num_resources; i++) {
308 struct resource *r = &pdev->resource[i];
309 unsigned long type = resource_type(r);
311 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
316 EXPORT_SYMBOL_GPL(platform_device_del);
319 * platform_device_register - add a platform-level device
320 * @pdev: platform device we're adding
322 int platform_device_register(struct platform_device *pdev)
324 device_initialize(&pdev->dev);
325 return platform_device_add(pdev);
327 EXPORT_SYMBOL_GPL(platform_device_register);
330 * platform_device_unregister - unregister a platform-level device
331 * @pdev: platform device we're unregistering
333 * Unregistration is done in 2 steps. First we release all resources
334 * and remove it from the subsystem, then we drop reference count by
335 * calling platform_device_put().
337 void platform_device_unregister(struct platform_device *pdev)
339 platform_device_del(pdev);
340 platform_device_put(pdev);
342 EXPORT_SYMBOL_GPL(platform_device_unregister);
345 * platform_device_register_simple
346 * @name: base name of the device we're adding
348 * @res: set of resources that needs to be allocated for the device
349 * @num: number of resources
351 * This function creates a simple platform device that requires minimal
352 * resource and memory management. Canned release function freeing memory
353 * allocated for the device allows drivers using such devices to be
354 * unloaded without waiting for the last reference to the device to be
357 * This interface is primarily intended for use with legacy drivers which
358 * probe hardware directly. Because such drivers create sysfs device nodes
359 * themselves, rather than letting system infrastructure handle such device
360 * enumeration tasks, they don't fully conform to the Linux driver model.
361 * In particular, when such drivers are built as modules, they can't be
364 struct platform_device *platform_device_register_simple(const char *name,
366 struct resource *res,
369 struct platform_device *pdev;
372 pdev = platform_device_alloc(name, id);
379 retval = platform_device_add_resources(pdev, res, num);
384 retval = platform_device_add(pdev);
391 platform_device_put(pdev);
392 return ERR_PTR(retval);
394 EXPORT_SYMBOL_GPL(platform_device_register_simple);
397 * platform_device_register_data
398 * @parent: parent device for the device we're adding
399 * @name: base name of the device we're adding
401 * @data: platform specific data for this platform device
402 * @size: size of platform specific data
404 * This function creates a simple platform device that requires minimal
405 * resource and memory management. Canned release function freeing memory
406 * allocated for the device allows drivers using such devices to be
407 * unloaded without waiting for the last reference to the device to be
410 struct platform_device *platform_device_register_data(
411 struct device *parent,
412 const char *name, int id,
413 const void *data, size_t size)
415 struct platform_device *pdev;
418 pdev = platform_device_alloc(name, id);
424 pdev->dev.parent = parent;
427 retval = platform_device_add_data(pdev, data, size);
432 retval = platform_device_add(pdev);
439 platform_device_put(pdev);
440 return ERR_PTR(retval);
443 static int platform_drv_probe(struct device *_dev)
445 struct platform_driver *drv = to_platform_driver(_dev->driver);
446 struct platform_device *dev = to_platform_device(_dev);
448 return drv->probe(dev);
451 static int platform_drv_probe_fail(struct device *_dev)
456 static int platform_drv_remove(struct device *_dev)
458 struct platform_driver *drv = to_platform_driver(_dev->driver);
459 struct platform_device *dev = to_platform_device(_dev);
461 return drv->remove(dev);
464 static void platform_drv_shutdown(struct device *_dev)
466 struct platform_driver *drv = to_platform_driver(_dev->driver);
467 struct platform_device *dev = to_platform_device(_dev);
472 static int platform_drv_suspend(struct device *_dev, pm_message_t state)
474 struct platform_driver *drv = to_platform_driver(_dev->driver);
475 struct platform_device *dev = to_platform_device(_dev);
477 return drv->suspend(dev, state);
480 static int platform_drv_resume(struct device *_dev)
482 struct platform_driver *drv = to_platform_driver(_dev->driver);
483 struct platform_device *dev = to_platform_device(_dev);
485 return drv->resume(dev);
489 * platform_driver_register
490 * @drv: platform driver structure
492 int platform_driver_register(struct platform_driver *drv)
494 drv->driver.bus = &platform_bus_type;
496 drv->driver.probe = platform_drv_probe;
498 drv->driver.remove = platform_drv_remove;
500 drv->driver.shutdown = platform_drv_shutdown;
502 drv->driver.suspend = platform_drv_suspend;
504 drv->driver.resume = platform_drv_resume;
505 return driver_register(&drv->driver);
507 EXPORT_SYMBOL_GPL(platform_driver_register);
510 * platform_driver_unregister
511 * @drv: platform driver structure
513 void platform_driver_unregister(struct platform_driver *drv)
515 driver_unregister(&drv->driver);
517 EXPORT_SYMBOL_GPL(platform_driver_unregister);
520 * platform_driver_probe - register driver for non-hotpluggable device
521 * @drv: platform driver structure
522 * @probe: the driver probe routine, probably from an __init section
524 * Use this instead of platform_driver_register() when you know the device
525 * is not hotpluggable and has already been registered, and you want to
526 * remove its run-once probe() infrastructure from memory after the driver
527 * has bound to the device.
529 * One typical use for this would be with drivers for controllers integrated
530 * into system-on-chip processors, where the controller devices have been
531 * configured as part of board setup.
533 * Returns zero if the driver registered and bound to a device, else returns
534 * a negative error code and with the driver not registered.
536 int __init_or_module platform_driver_probe(struct platform_driver *drv,
537 int (*probe)(struct platform_device *))
541 /* temporary section violation during probe() */
543 retval = code = platform_driver_register(drv);
545 /* Fixup that section violation, being paranoid about code scanning
546 * the list of drivers in order to probe new devices. Check to see
547 * if the probe was successful, and make sure any forced probes of
550 spin_lock(&platform_bus_type.p->klist_drivers.k_lock);
552 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
554 drv->driver.probe = platform_drv_probe_fail;
555 spin_unlock(&platform_bus_type.p->klist_drivers.k_lock);
558 platform_driver_unregister(drv);
561 EXPORT_SYMBOL_GPL(platform_driver_probe);
563 /* modalias support enables more hands-off userspace setup:
564 * (a) environment variable lets new-style hotplug events work once system is
565 * fully running: "modprobe $MODALIAS"
566 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
567 * mishandled before system is fully running: "modprobe $(cat modalias)"
569 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
572 struct platform_device *pdev = to_platform_device(dev);
573 int len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
575 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
578 static struct device_attribute platform_dev_attrs[] = {
583 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
585 struct platform_device *pdev = to_platform_device(dev);
587 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
588 (pdev->id_entry) ? pdev->id_entry->name : pdev->name);
592 static const struct platform_device_id *platform_match_id(
593 struct platform_device_id *id,
594 struct platform_device *pdev)
596 while (id->name[0]) {
597 if (strcmp(pdev->name, id->name) == 0) {
607 * platform_match - bind platform device to platform driver.
611 * Platform device IDs are assumed to be encoded like this:
612 * "<name><instance>", where <name> is a short description of the type of
613 * device, like "pci" or "floppy", and <instance> is the enumerated
614 * instance of the device, like '0' or '42'. Driver IDs are simply
615 * "<name>". So, extract the <name> from the platform_device structure,
616 * and compare it against the name of the driver. Return whether they match
619 static int platform_match(struct device *dev, struct device_driver *drv)
621 struct platform_device *pdev = to_platform_device(dev);
622 struct platform_driver *pdrv = to_platform_driver(drv);
624 /* match against the id table first */
626 return platform_match_id(pdrv->id_table, pdev) != NULL;
628 /* fall-back to driver name match */
629 return (strcmp(pdev->name, drv->name) == 0);
632 #ifdef CONFIG_PM_SLEEP
634 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
638 if (dev->driver && dev->driver->suspend)
639 ret = dev->driver->suspend(dev, mesg);
644 static int platform_legacy_suspend_late(struct device *dev, pm_message_t mesg)
646 struct platform_driver *pdrv = to_platform_driver(dev->driver);
647 struct platform_device *pdev = to_platform_device(dev);
650 if (dev->driver && pdrv->suspend_late)
651 ret = pdrv->suspend_late(pdev, mesg);
656 static int platform_legacy_resume_early(struct device *dev)
658 struct platform_driver *pdrv = to_platform_driver(dev->driver);
659 struct platform_device *pdev = to_platform_device(dev);
662 if (dev->driver && pdrv->resume_early)
663 ret = pdrv->resume_early(pdev);
668 static int platform_legacy_resume(struct device *dev)
672 if (dev->driver && dev->driver->resume)
673 ret = dev->driver->resume(dev);
678 static int platform_pm_prepare(struct device *dev)
680 struct device_driver *drv = dev->driver;
683 if (drv && drv->pm && drv->pm->prepare)
684 ret = drv->pm->prepare(dev);
689 static void platform_pm_complete(struct device *dev)
691 struct device_driver *drv = dev->driver;
693 if (drv && drv->pm && drv->pm->complete)
694 drv->pm->complete(dev);
697 #ifdef CONFIG_SUSPEND
699 static int platform_pm_suspend(struct device *dev)
701 struct device_driver *drv = dev->driver;
708 if (drv->pm->suspend)
709 ret = drv->pm->suspend(dev);
711 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
717 static int platform_pm_suspend_noirq(struct device *dev)
719 struct device_driver *drv = dev->driver;
726 if (drv->pm->suspend_noirq)
727 ret = drv->pm->suspend_noirq(dev);
729 ret = platform_legacy_suspend_late(dev, PMSG_SUSPEND);
735 static int platform_pm_resume(struct device *dev)
737 struct device_driver *drv = dev->driver;
745 ret = drv->pm->resume(dev);
747 ret = platform_legacy_resume(dev);
753 static int platform_pm_resume_noirq(struct device *dev)
755 struct device_driver *drv = dev->driver;
762 if (drv->pm->resume_noirq)
763 ret = drv->pm->resume_noirq(dev);
765 ret = platform_legacy_resume_early(dev);
771 #else /* !CONFIG_SUSPEND */
773 #define platform_pm_suspend NULL
774 #define platform_pm_resume NULL
775 #define platform_pm_suspend_noirq NULL
776 #define platform_pm_resume_noirq NULL
778 #endif /* !CONFIG_SUSPEND */
780 #ifdef CONFIG_HIBERNATION
782 static int platform_pm_freeze(struct device *dev)
784 struct device_driver *drv = dev->driver;
792 ret = drv->pm->freeze(dev);
794 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
800 static int platform_pm_freeze_noirq(struct device *dev)
802 struct device_driver *drv = dev->driver;
809 if (drv->pm->freeze_noirq)
810 ret = drv->pm->freeze_noirq(dev);
812 ret = platform_legacy_suspend_late(dev, PMSG_FREEZE);
818 static int platform_pm_thaw(struct device *dev)
820 struct device_driver *drv = dev->driver;
828 ret = drv->pm->thaw(dev);
830 ret = platform_legacy_resume(dev);
836 static int platform_pm_thaw_noirq(struct device *dev)
838 struct device_driver *drv = dev->driver;
845 if (drv->pm->thaw_noirq)
846 ret = drv->pm->thaw_noirq(dev);
848 ret = platform_legacy_resume_early(dev);
854 static int platform_pm_poweroff(struct device *dev)
856 struct device_driver *drv = dev->driver;
863 if (drv->pm->poweroff)
864 ret = drv->pm->poweroff(dev);
866 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
872 static int platform_pm_poweroff_noirq(struct device *dev)
874 struct device_driver *drv = dev->driver;
881 if (drv->pm->poweroff_noirq)
882 ret = drv->pm->poweroff_noirq(dev);
884 ret = platform_legacy_suspend_late(dev, PMSG_HIBERNATE);
890 static int platform_pm_restore(struct device *dev)
892 struct device_driver *drv = dev->driver;
899 if (drv->pm->restore)
900 ret = drv->pm->restore(dev);
902 ret = platform_legacy_resume(dev);
908 static int platform_pm_restore_noirq(struct device *dev)
910 struct device_driver *drv = dev->driver;
917 if (drv->pm->restore_noirq)
918 ret = drv->pm->restore_noirq(dev);
920 ret = platform_legacy_resume_early(dev);
926 #else /* !CONFIG_HIBERNATION */
928 #define platform_pm_freeze NULL
929 #define platform_pm_thaw NULL
930 #define platform_pm_poweroff NULL
931 #define platform_pm_restore NULL
932 #define platform_pm_freeze_noirq NULL
933 #define platform_pm_thaw_noirq NULL
934 #define platform_pm_poweroff_noirq NULL
935 #define platform_pm_restore_noirq NULL
937 #endif /* !CONFIG_HIBERNATION */
939 static struct dev_pm_ops platform_dev_pm_ops = {
940 .prepare = platform_pm_prepare,
941 .complete = platform_pm_complete,
942 .suspend = platform_pm_suspend,
943 .resume = platform_pm_resume,
944 .freeze = platform_pm_freeze,
945 .thaw = platform_pm_thaw,
946 .poweroff = platform_pm_poweroff,
947 .restore = platform_pm_restore,
948 .suspend_noirq = platform_pm_suspend_noirq,
949 .resume_noirq = platform_pm_resume_noirq,
950 .freeze_noirq = platform_pm_freeze_noirq,
951 .thaw_noirq = platform_pm_thaw_noirq,
952 .poweroff_noirq = platform_pm_poweroff_noirq,
953 .restore_noirq = platform_pm_restore_noirq,
956 #define PLATFORM_PM_OPS_PTR (&platform_dev_pm_ops)
958 #else /* !CONFIG_PM_SLEEP */
960 #define PLATFORM_PM_OPS_PTR NULL
962 #endif /* !CONFIG_PM_SLEEP */
964 struct bus_type platform_bus_type = {
966 .dev_attrs = platform_dev_attrs,
967 .match = platform_match,
968 .uevent = platform_uevent,
969 .pm = PLATFORM_PM_OPS_PTR,
971 EXPORT_SYMBOL_GPL(platform_bus_type);
973 int __init platform_bus_init(void)
977 early_platform_cleanup();
979 error = device_register(&platform_bus);
982 error = bus_register(&platform_bus_type);
984 device_unregister(&platform_bus);
988 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
989 u64 dma_get_required_mask(struct device *dev)
991 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
992 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
995 if (!high_totalram) {
996 /* convert to mask just covering totalram */
997 low_totalram = (1 << (fls(low_totalram) - 1));
998 low_totalram += low_totalram - 1;
1001 high_totalram = (1 << (fls(high_totalram) - 1));
1002 high_totalram += high_totalram - 1;
1003 mask = (((u64)high_totalram) << 32) + 0xffffffff;
1007 EXPORT_SYMBOL_GPL(dma_get_required_mask);
1010 static __initdata LIST_HEAD(early_platform_driver_list);
1011 static __initdata LIST_HEAD(early_platform_device_list);
1014 * early_platform_driver_register
1015 * @epdrv: early_platform driver structure
1016 * @buf: string passed from early_param()
1018 int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1021 unsigned long index;
1024 /* Simply add the driver to the end of the global list.
1025 * Drivers will by default be put on the list in compiled-in order.
1027 if (!epdrv->list.next) {
1028 INIT_LIST_HEAD(&epdrv->list);
1029 list_add_tail(&epdrv->list, &early_platform_driver_list);
1032 /* If the user has specified device then make sure the driver
1033 * gets prioritized. The driver of the last device specified on
1034 * command line will be put first on the list.
1036 n = strlen(epdrv->pdrv->driver.name);
1037 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1038 list_move(&epdrv->list, &early_platform_driver_list);
1040 if (!strcmp(buf, epdrv->pdrv->driver.name))
1041 epdrv->requested_id = -1;
1042 else if (buf[n] == '.' && strict_strtoul(&buf[n + 1], 10,
1044 epdrv->requested_id = index;
1046 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1053 * early_platform_add_devices - add a numbers of early platform devices
1054 * @devs: array of early platform devices to add
1055 * @num: number of early platform devices in array
1057 void __init early_platform_add_devices(struct platform_device **devs, int num)
1062 /* simply add the devices to list */
1063 for (i = 0; i < num; i++) {
1064 dev = &devs[i]->dev;
1066 if (!dev->devres_head.next) {
1067 INIT_LIST_HEAD(&dev->devres_head);
1068 list_add_tail(&dev->devres_head,
1069 &early_platform_device_list);
1075 * early_platform_driver_register_all
1076 * @class_str: string to identify early platform driver class
1078 void __init early_platform_driver_register_all(char *class_str)
1080 /* The "class_str" parameter may or may not be present on the kernel
1081 * command line. If it is present then there may be more than one
1082 * matching parameter.
1084 * Since we register our early platform drivers using early_param()
1085 * we need to make sure that they also get registered in the case
1086 * when the parameter is missing from the kernel command line.
1088 * We use parse_early_options() to make sure the early_param() gets
1089 * called at least once. The early_param() may be called more than
1090 * once since the name of the preferred device may be specified on
1091 * the kernel command line. early_platform_driver_register() handles
1094 parse_early_options(class_str);
1098 * early_platform_match
1099 * @epdrv: early platform driver structure
1100 * @id: id to match against
1102 static __init struct platform_device *
1103 early_platform_match(struct early_platform_driver *epdrv, int id)
1105 struct platform_device *pd;
1107 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1108 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1116 * early_platform_left
1117 * @epdrv: early platform driver structure
1118 * @id: return true if id or above exists
1120 static __init int early_platform_left(struct early_platform_driver *epdrv,
1123 struct platform_device *pd;
1125 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1126 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1134 * early_platform_driver_probe_id
1135 * @class_str: string to identify early platform driver class
1136 * @id: id to match against
1137 * @nr_probe: number of platform devices to successfully probe before exiting
1139 static int __init early_platform_driver_probe_id(char *class_str,
1143 struct early_platform_driver *epdrv;
1144 struct platform_device *match;
1149 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1150 /* only use drivers matching our class_str */
1151 if (strcmp(class_str, epdrv->class_str))
1155 match_id = epdrv->requested_id;
1160 left += early_platform_left(epdrv, id);
1162 /* skip requested id */
1163 switch (epdrv->requested_id) {
1164 case EARLY_PLATFORM_ID_ERROR:
1165 case EARLY_PLATFORM_ID_UNSET:
1168 if (epdrv->requested_id == id)
1169 match_id = EARLY_PLATFORM_ID_UNSET;
1174 case EARLY_PLATFORM_ID_ERROR:
1175 pr_warning("%s: unable to parse %s parameter\n",
1176 class_str, epdrv->pdrv->driver.name);
1178 case EARLY_PLATFORM_ID_UNSET:
1182 match = early_platform_match(epdrv, match_id);
1186 if (epdrv->pdrv->probe(match))
1187 pr_warning("%s: unable to probe %s early.\n",
1188 class_str, match->name);
1204 * early_platform_driver_probe
1205 * @class_str: string to identify early platform driver class
1206 * @nr_probe: number of platform devices to successfully probe before exiting
1207 * @user_only: only probe user specified early platform devices
1209 int __init early_platform_driver_probe(char *class_str,
1216 for (i = -2; n < nr_probe; i++) {
1217 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1232 * early_platform_cleanup - clean up early platform code
1234 void __init early_platform_cleanup(void)
1236 struct platform_device *pd, *pd2;
1238 /* clean up the devres list used to chain devices */
1239 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1241 list_del(&pd->dev.devres_head);
1242 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));