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>
23 #include <linux/idr.h>
24 #include <linux/acpi.h>
27 #include "power/power.h"
29 /* For automatically allocated device IDs */
30 static DEFINE_IDA(platform_devid_ida);
32 struct device platform_bus = {
33 .init_name = "platform",
35 EXPORT_SYMBOL_GPL(platform_bus);
38 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
39 * @pdev: platform device
41 * This is called before platform_device_add() such that any pdev_archdata may
42 * be setup before the platform_notifier is called. So if a user needs to
43 * manipulate any relevant information in the pdev_archdata they can do:
45 * platform_device_alloc()
47 * platform_device_add()
49 * And if they don't care they can just call platform_device_register() and
50 * everything will just work out.
52 void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
57 * platform_get_resource - get a resource for a device
58 * @dev: platform device
59 * @type: resource type
60 * @num: resource index
62 struct resource *platform_get_resource(struct platform_device *dev,
63 unsigned int type, unsigned int num)
67 for (i = 0; i < dev->num_resources; i++) {
68 struct resource *r = &dev->resource[i];
70 if (type == resource_type(r) && num-- == 0)
75 EXPORT_SYMBOL_GPL(platform_get_resource);
78 * platform_get_irq - get an IRQ for a device
79 * @dev: platform device
80 * @num: IRQ number index
82 int platform_get_irq(struct platform_device *dev, unsigned int num)
85 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
86 if (!dev || num >= dev->archdata.num_irqs)
88 return dev->archdata.irqs[num];
90 struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
92 return r ? r->start : -ENXIO;
95 EXPORT_SYMBOL_GPL(platform_get_irq);
98 * platform_get_resource_byname - get a resource for a device by name
99 * @dev: platform device
100 * @type: resource type
101 * @name: resource name
103 struct resource *platform_get_resource_byname(struct platform_device *dev,
109 for (i = 0; i < dev->num_resources; i++) {
110 struct resource *r = &dev->resource[i];
112 if (unlikely(!r->name))
115 if (type == resource_type(r) && !strcmp(r->name, name))
120 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
123 * platform_get_irq_byname - get an IRQ for a device by name
124 * @dev: platform device
127 int platform_get_irq_byname(struct platform_device *dev, const char *name)
129 struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
132 return r ? r->start : -ENXIO;
134 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
137 * platform_add_devices - add a numbers of platform devices
138 * @devs: array of platform devices to add
139 * @num: number of platform devices in array
141 int platform_add_devices(struct platform_device **devs, int num)
145 for (i = 0; i < num; i++) {
146 ret = platform_device_register(devs[i]);
149 platform_device_unregister(devs[i]);
156 EXPORT_SYMBOL_GPL(platform_add_devices);
158 struct platform_object {
159 struct platform_device pdev;
164 * platform_device_put - destroy a platform device
165 * @pdev: platform device to free
167 * Free all memory associated with a platform device. This function must
168 * _only_ be externally called in error cases. All other usage is a bug.
170 void platform_device_put(struct platform_device *pdev)
173 put_device(&pdev->dev);
175 EXPORT_SYMBOL_GPL(platform_device_put);
177 static void platform_device_release(struct device *dev)
179 struct platform_object *pa = container_of(dev, struct platform_object,
182 of_device_node_put(&pa->pdev.dev);
183 kfree(pa->pdev.dev.platform_data);
184 kfree(pa->pdev.mfd_cell);
185 kfree(pa->pdev.resource);
190 * platform_device_alloc - create a platform device
191 * @name: base name of the device we're adding
194 * Create a platform device object which can have other objects attached
195 * to it, and which will have attached objects freed when it is released.
197 struct platform_device *platform_device_alloc(const char *name, int id)
199 struct platform_object *pa;
201 pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
203 strcpy(pa->name, name);
204 pa->pdev.name = pa->name;
206 device_initialize(&pa->pdev.dev);
207 pa->pdev.dev.release = platform_device_release;
208 arch_setup_pdev_archdata(&pa->pdev);
211 return pa ? &pa->pdev : NULL;
213 EXPORT_SYMBOL_GPL(platform_device_alloc);
216 * platform_device_add_resources - add resources to a platform device
217 * @pdev: platform device allocated by platform_device_alloc to add resources to
218 * @res: set of resources that needs to be allocated for the device
219 * @num: number of resources
221 * Add a copy of the resources to the platform device. The memory
222 * associated with the resources will be freed when the platform device is
225 int platform_device_add_resources(struct platform_device *pdev,
226 const struct resource *res, unsigned int num)
228 struct resource *r = NULL;
231 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
236 kfree(pdev->resource);
238 pdev->num_resources = num;
241 EXPORT_SYMBOL_GPL(platform_device_add_resources);
244 * platform_device_add_data - add platform-specific data to a platform device
245 * @pdev: platform device allocated by platform_device_alloc to add resources to
246 * @data: platform specific data for this platform device
247 * @size: size of platform specific data
249 * Add a copy of platform specific data to the platform device's
250 * platform_data pointer. The memory associated with the platform data
251 * will be freed when the platform device is released.
253 int platform_device_add_data(struct platform_device *pdev, const void *data,
259 d = kmemdup(data, size, GFP_KERNEL);
264 kfree(pdev->dev.platform_data);
265 pdev->dev.platform_data = d;
268 EXPORT_SYMBOL_GPL(platform_device_add_data);
271 * platform_device_add - add a platform device to device hierarchy
272 * @pdev: platform device we're adding
274 * This is part 2 of platform_device_register(), though may be called
275 * separately _iff_ pdev was allocated by platform_device_alloc().
277 int platform_device_add(struct platform_device *pdev)
284 if (!pdev->dev.parent)
285 pdev->dev.parent = &platform_bus;
287 pdev->dev.bus = &platform_bus_type;
291 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
293 case PLATFORM_DEVID_NONE:
294 dev_set_name(&pdev->dev, "%s", pdev->name);
296 case PLATFORM_DEVID_AUTO:
298 * Automatically allocated device ID. We mark it as such so
299 * that we remember it must be freed, and we append a suffix
300 * to avoid namespace collision with explicit IDs.
302 ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
306 pdev->id_auto = true;
307 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
311 for (i = 0; i < pdev->num_resources; i++) {
312 struct resource *p, *r = &pdev->resource[i];
315 r->name = dev_name(&pdev->dev);
319 if (resource_type(r) == IORESOURCE_MEM)
321 else if (resource_type(r) == IORESOURCE_IO)
322 p = &ioport_resource;
325 if (p && insert_resource(p, r)) {
326 dev_err(&pdev->dev, "failed to claim resource %d\n", i);
332 pr_debug("Registering platform device '%s'. Parent at %s\n",
333 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
335 ret = device_add(&pdev->dev);
341 ida_simple_remove(&platform_devid_ida, pdev->id);
342 pdev->id = PLATFORM_DEVID_AUTO;
346 struct resource *r = &pdev->resource[i];
347 unsigned long type = resource_type(r);
349 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
356 EXPORT_SYMBOL_GPL(platform_device_add);
359 * platform_device_del - remove a platform-level device
360 * @pdev: platform device we're removing
362 * Note that this function will also release all memory- and port-based
363 * resources owned by the device (@dev->resource). This function must
364 * _only_ be externally called in error cases. All other usage is a bug.
366 void platform_device_del(struct platform_device *pdev)
371 device_del(&pdev->dev);
374 ida_simple_remove(&platform_devid_ida, pdev->id);
375 pdev->id = PLATFORM_DEVID_AUTO;
378 for (i = 0; i < pdev->num_resources; i++) {
379 struct resource *r = &pdev->resource[i];
380 unsigned long type = resource_type(r);
382 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
387 EXPORT_SYMBOL_GPL(platform_device_del);
390 * platform_device_register - add a platform-level device
391 * @pdev: platform device we're adding
393 int platform_device_register(struct platform_device *pdev)
395 device_initialize(&pdev->dev);
396 arch_setup_pdev_archdata(pdev);
397 return platform_device_add(pdev);
399 EXPORT_SYMBOL_GPL(platform_device_register);
402 * platform_device_unregister - unregister a platform-level device
403 * @pdev: platform device we're unregistering
405 * Unregistration is done in 2 steps. First we release all resources
406 * and remove it from the subsystem, then we drop reference count by
407 * calling platform_device_put().
409 void platform_device_unregister(struct platform_device *pdev)
411 platform_device_del(pdev);
412 platform_device_put(pdev);
414 EXPORT_SYMBOL_GPL(platform_device_unregister);
417 * platform_device_register_full - add a platform-level device with
418 * resources and platform-specific data
420 * @pdevinfo: data used to create device
422 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
424 struct platform_device *platform_device_register_full(
425 const struct platform_device_info *pdevinfo)
428 struct platform_device *pdev;
430 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
434 pdev->dev.parent = pdevinfo->parent;
435 ACPI_COMPANION_SET(&pdev->dev, pdevinfo->acpi_node.companion);
437 if (pdevinfo->dma_mask) {
439 * This memory isn't freed when the device is put,
440 * I don't have a nice idea for that though. Conceptually
441 * dma_mask in struct device should not be a pointer.
442 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
445 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
446 if (!pdev->dev.dma_mask)
449 *pdev->dev.dma_mask = pdevinfo->dma_mask;
450 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
453 ret = platform_device_add_resources(pdev,
454 pdevinfo->res, pdevinfo->num_res);
458 ret = platform_device_add_data(pdev,
459 pdevinfo->data, pdevinfo->size_data);
463 ret = platform_device_add(pdev);
466 ACPI_COMPANION_SET(&pdev->dev, NULL);
467 kfree(pdev->dev.dma_mask);
470 platform_device_put(pdev);
476 EXPORT_SYMBOL_GPL(platform_device_register_full);
478 static int platform_drv_probe(struct device *_dev)
480 struct platform_driver *drv = to_platform_driver(_dev->driver);
481 struct platform_device *dev = to_platform_device(_dev);
484 if (ACPI_HANDLE(_dev))
485 acpi_dev_pm_attach(_dev, true);
487 ret = drv->probe(dev);
488 if (ret && ACPI_HANDLE(_dev))
489 acpi_dev_pm_detach(_dev, true);
491 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
492 dev_warn(_dev, "probe deferral not supported\n");
499 static int platform_drv_probe_fail(struct device *_dev)
504 static int platform_drv_remove(struct device *_dev)
506 struct platform_driver *drv = to_platform_driver(_dev->driver);
507 struct platform_device *dev = to_platform_device(_dev);
510 ret = drv->remove(dev);
511 if (ACPI_HANDLE(_dev))
512 acpi_dev_pm_detach(_dev, true);
517 static void platform_drv_shutdown(struct device *_dev)
519 struct platform_driver *drv = to_platform_driver(_dev->driver);
520 struct platform_device *dev = to_platform_device(_dev);
523 if (ACPI_HANDLE(_dev))
524 acpi_dev_pm_detach(_dev, true);
528 * __platform_driver_register - register a driver for platform-level devices
529 * @drv: platform driver structure
530 * @owner: owning module/driver
532 int __platform_driver_register(struct platform_driver *drv,
533 struct module *owner)
535 drv->driver.owner = owner;
536 drv->driver.bus = &platform_bus_type;
538 drv->driver.probe = platform_drv_probe;
540 drv->driver.remove = platform_drv_remove;
542 drv->driver.shutdown = platform_drv_shutdown;
544 return driver_register(&drv->driver);
546 EXPORT_SYMBOL_GPL(__platform_driver_register);
549 * platform_driver_unregister - unregister a driver for platform-level devices
550 * @drv: platform driver structure
552 void platform_driver_unregister(struct platform_driver *drv)
554 driver_unregister(&drv->driver);
556 EXPORT_SYMBOL_GPL(platform_driver_unregister);
559 * platform_driver_probe - register driver for non-hotpluggable device
560 * @drv: platform driver structure
561 * @probe: the driver probe routine, probably from an __init section
563 * Use this instead of platform_driver_register() when you know the device
564 * is not hotpluggable and has already been registered, and you want to
565 * remove its run-once probe() infrastructure from memory after the driver
566 * has bound to the device.
568 * One typical use for this would be with drivers for controllers integrated
569 * into system-on-chip processors, where the controller devices have been
570 * configured as part of board setup.
572 * Note that this is incompatible with deferred probing.
574 * Returns zero if the driver registered and bound to a device, else returns
575 * a negative error code and with the driver not registered.
577 int __init_or_module platform_driver_probe(struct platform_driver *drv,
578 int (*probe)(struct platform_device *))
583 * Prevent driver from requesting probe deferral to avoid further
584 * futile probe attempts.
586 drv->prevent_deferred_probe = true;
588 /* make sure driver won't have bind/unbind attributes */
589 drv->driver.suppress_bind_attrs = true;
591 /* temporary section violation during probe() */
593 retval = code = platform_driver_register(drv);
596 * Fixup that section violation, being paranoid about code scanning
597 * the list of drivers in order to probe new devices. Check to see
598 * if the probe was successful, and make sure any forced probes of
601 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
603 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
605 drv->driver.probe = platform_drv_probe_fail;
606 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
609 platform_driver_unregister(drv);
612 EXPORT_SYMBOL_GPL(platform_driver_probe);
615 * platform_create_bundle - register driver and create corresponding device
616 * @driver: platform driver structure
617 * @probe: the driver probe routine, probably from an __init section
618 * @res: set of resources that needs to be allocated for the device
619 * @n_res: number of resources
620 * @data: platform specific data for this platform device
621 * @size: size of platform specific data
623 * Use this in legacy-style modules that probe hardware directly and
624 * register a single platform device and corresponding platform driver.
626 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
628 struct platform_device * __init_or_module platform_create_bundle(
629 struct platform_driver *driver,
630 int (*probe)(struct platform_device *),
631 struct resource *res, unsigned int n_res,
632 const void *data, size_t size)
634 struct platform_device *pdev;
637 pdev = platform_device_alloc(driver->driver.name, -1);
643 error = platform_device_add_resources(pdev, res, n_res);
647 error = platform_device_add_data(pdev, data, size);
651 error = platform_device_add(pdev);
655 error = platform_driver_probe(driver, probe);
662 platform_device_del(pdev);
664 platform_device_put(pdev);
666 return ERR_PTR(error);
668 EXPORT_SYMBOL_GPL(platform_create_bundle);
670 /* modalias support enables more hands-off userspace setup:
671 * (a) environment variable lets new-style hotplug events work once system is
672 * fully running: "modprobe $MODALIAS"
673 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
674 * mishandled before system is fully running: "modprobe $(cat modalias)"
676 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
679 struct platform_device *pdev = to_platform_device(dev);
682 len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
686 len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
690 len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
692 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
694 static DEVICE_ATTR_RO(modalias);
696 static struct attribute *platform_dev_attrs[] = {
697 &dev_attr_modalias.attr,
700 ATTRIBUTE_GROUPS(platform_dev);
702 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
704 struct platform_device *pdev = to_platform_device(dev);
707 /* Some devices have extra OF data and an OF-style MODALIAS */
708 rc = of_device_uevent_modalias(dev, env);
712 rc = acpi_device_uevent_modalias(dev, env);
716 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
721 static const struct platform_device_id *platform_match_id(
722 const struct platform_device_id *id,
723 struct platform_device *pdev)
725 while (id->name[0]) {
726 if (strcmp(pdev->name, id->name) == 0) {
736 * platform_match - bind platform device to platform driver.
740 * Platform device IDs are assumed to be encoded like this:
741 * "<name><instance>", where <name> is a short description of the type of
742 * device, like "pci" or "floppy", and <instance> is the enumerated
743 * instance of the device, like '0' or '42'. Driver IDs are simply
744 * "<name>". So, extract the <name> from the platform_device structure,
745 * and compare it against the name of the driver. Return whether they match
748 static int platform_match(struct device *dev, struct device_driver *drv)
750 struct platform_device *pdev = to_platform_device(dev);
751 struct platform_driver *pdrv = to_platform_driver(drv);
753 /* Attempt an OF style match first */
754 if (of_driver_match_device(dev, drv))
757 /* Then try ACPI style match */
758 if (acpi_driver_match_device(dev, drv))
761 /* Then try to match against the id table */
763 return platform_match_id(pdrv->id_table, pdev) != NULL;
765 /* fall-back to driver name match */
766 return (strcmp(pdev->name, drv->name) == 0);
769 #ifdef CONFIG_PM_SLEEP
771 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
773 struct platform_driver *pdrv = to_platform_driver(dev->driver);
774 struct platform_device *pdev = to_platform_device(dev);
777 if (dev->driver && pdrv->suspend)
778 ret = pdrv->suspend(pdev, mesg);
783 static int platform_legacy_resume(struct device *dev)
785 struct platform_driver *pdrv = to_platform_driver(dev->driver);
786 struct platform_device *pdev = to_platform_device(dev);
789 if (dev->driver && pdrv->resume)
790 ret = pdrv->resume(pdev);
795 #endif /* CONFIG_PM_SLEEP */
797 #ifdef CONFIG_SUSPEND
799 int platform_pm_suspend(struct device *dev)
801 struct device_driver *drv = dev->driver;
808 if (drv->pm->suspend)
809 ret = drv->pm->suspend(dev);
811 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
817 int platform_pm_resume(struct device *dev)
819 struct device_driver *drv = dev->driver;
827 ret = drv->pm->resume(dev);
829 ret = platform_legacy_resume(dev);
835 #endif /* CONFIG_SUSPEND */
837 #ifdef CONFIG_HIBERNATE_CALLBACKS
839 int platform_pm_freeze(struct device *dev)
841 struct device_driver *drv = dev->driver;
849 ret = drv->pm->freeze(dev);
851 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
857 int platform_pm_thaw(struct device *dev)
859 struct device_driver *drv = dev->driver;
867 ret = drv->pm->thaw(dev);
869 ret = platform_legacy_resume(dev);
875 int platform_pm_poweroff(struct device *dev)
877 struct device_driver *drv = dev->driver;
884 if (drv->pm->poweroff)
885 ret = drv->pm->poweroff(dev);
887 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
893 int platform_pm_restore(struct device *dev)
895 struct device_driver *drv = dev->driver;
902 if (drv->pm->restore)
903 ret = drv->pm->restore(dev);
905 ret = platform_legacy_resume(dev);
911 #endif /* CONFIG_HIBERNATE_CALLBACKS */
913 static const struct dev_pm_ops platform_dev_pm_ops = {
914 .runtime_suspend = pm_generic_runtime_suspend,
915 .runtime_resume = pm_generic_runtime_resume,
916 USE_PLATFORM_PM_SLEEP_OPS
919 struct bus_type platform_bus_type = {
921 .dev_groups = platform_dev_groups,
922 .match = platform_match,
923 .uevent = platform_uevent,
924 .pm = &platform_dev_pm_ops,
926 EXPORT_SYMBOL_GPL(platform_bus_type);
928 int __init platform_bus_init(void)
932 early_platform_cleanup();
934 error = device_register(&platform_bus);
937 error = bus_register(&platform_bus_type);
939 device_unregister(&platform_bus);
943 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
944 u64 dma_get_required_mask(struct device *dev)
946 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
947 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
950 if (!high_totalram) {
951 /* convert to mask just covering totalram */
952 low_totalram = (1 << (fls(low_totalram) - 1));
953 low_totalram += low_totalram - 1;
956 high_totalram = (1 << (fls(high_totalram) - 1));
957 high_totalram += high_totalram - 1;
958 mask = (((u64)high_totalram) << 32) + 0xffffffff;
962 EXPORT_SYMBOL_GPL(dma_get_required_mask);
965 static __initdata LIST_HEAD(early_platform_driver_list);
966 static __initdata LIST_HEAD(early_platform_device_list);
969 * early_platform_driver_register - register early platform driver
970 * @epdrv: early_platform driver structure
971 * @buf: string passed from early_param()
973 * Helper function for early_platform_init() / early_platform_init_buffer()
975 int __init early_platform_driver_register(struct early_platform_driver *epdrv,
981 /* Simply add the driver to the end of the global list.
982 * Drivers will by default be put on the list in compiled-in order.
984 if (!epdrv->list.next) {
985 INIT_LIST_HEAD(&epdrv->list);
986 list_add_tail(&epdrv->list, &early_platform_driver_list);
989 /* If the user has specified device then make sure the driver
990 * gets prioritized. The driver of the last device specified on
991 * command line will be put first on the list.
993 n = strlen(epdrv->pdrv->driver.name);
994 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
995 list_move(&epdrv->list, &early_platform_driver_list);
997 /* Allow passing parameters after device name */
998 if (buf[n] == '\0' || buf[n] == ',')
999 epdrv->requested_id = -1;
1001 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1004 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1005 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1008 n += strcspn(&buf[n + 1], ",") + 1;
1014 if (epdrv->bufsize) {
1015 memcpy(epdrv->buffer, &buf[n],
1016 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1017 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1025 * early_platform_add_devices - adds a number of early platform devices
1026 * @devs: array of early platform devices to add
1027 * @num: number of early platform devices in array
1029 * Used by early architecture code to register early platform devices and
1030 * their platform data.
1032 void __init early_platform_add_devices(struct platform_device **devs, int num)
1037 /* simply add the devices to list */
1038 for (i = 0; i < num; i++) {
1039 dev = &devs[i]->dev;
1041 if (!dev->devres_head.next) {
1042 pm_runtime_early_init(dev);
1043 INIT_LIST_HEAD(&dev->devres_head);
1044 list_add_tail(&dev->devres_head,
1045 &early_platform_device_list);
1051 * early_platform_driver_register_all - register early platform drivers
1052 * @class_str: string to identify early platform driver class
1054 * Used by architecture code to register all early platform drivers
1055 * for a certain class. If omitted then only early platform drivers
1056 * with matching kernel command line class parameters will be registered.
1058 void __init early_platform_driver_register_all(char *class_str)
1060 /* The "class_str" parameter may or may not be present on the kernel
1061 * command line. If it is present then there may be more than one
1062 * matching parameter.
1064 * Since we register our early platform drivers using early_param()
1065 * we need to make sure that they also get registered in the case
1066 * when the parameter is missing from the kernel command line.
1068 * We use parse_early_options() to make sure the early_param() gets
1069 * called at least once. The early_param() may be called more than
1070 * once since the name of the preferred device may be specified on
1071 * the kernel command line. early_platform_driver_register() handles
1074 parse_early_options(class_str);
1078 * early_platform_match - find early platform device matching driver
1079 * @epdrv: early platform driver structure
1080 * @id: id to match against
1082 static struct platform_device * __init
1083 early_platform_match(struct early_platform_driver *epdrv, int id)
1085 struct platform_device *pd;
1087 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1088 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1096 * early_platform_left - check if early platform driver has matching devices
1097 * @epdrv: early platform driver structure
1098 * @id: return true if id or above exists
1100 static int __init early_platform_left(struct early_platform_driver *epdrv,
1103 struct platform_device *pd;
1105 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1106 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1114 * early_platform_driver_probe_id - probe drivers matching class_str and id
1115 * @class_str: string to identify early platform driver class
1116 * @id: id to match against
1117 * @nr_probe: number of platform devices to successfully probe before exiting
1119 static int __init early_platform_driver_probe_id(char *class_str,
1123 struct early_platform_driver *epdrv;
1124 struct platform_device *match;
1129 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1130 /* only use drivers matching our class_str */
1131 if (strcmp(class_str, epdrv->class_str))
1135 match_id = epdrv->requested_id;
1140 left += early_platform_left(epdrv, id);
1142 /* skip requested id */
1143 switch (epdrv->requested_id) {
1144 case EARLY_PLATFORM_ID_ERROR:
1145 case EARLY_PLATFORM_ID_UNSET:
1148 if (epdrv->requested_id == id)
1149 match_id = EARLY_PLATFORM_ID_UNSET;
1154 case EARLY_PLATFORM_ID_ERROR:
1155 pr_warn("%s: unable to parse %s parameter\n",
1156 class_str, epdrv->pdrv->driver.name);
1158 case EARLY_PLATFORM_ID_UNSET:
1162 match = early_platform_match(epdrv, match_id);
1167 * Set up a sensible init_name to enable
1168 * dev_name() and others to be used before the
1169 * rest of the driver core is initialized.
1171 if (!match->dev.init_name && slab_is_available()) {
1172 if (match->id != -1)
1173 match->dev.init_name =
1174 kasprintf(GFP_KERNEL, "%s.%d",
1178 match->dev.init_name =
1179 kasprintf(GFP_KERNEL, "%s",
1182 if (!match->dev.init_name)
1186 if (epdrv->pdrv->probe(match))
1187 pr_warn("%s: unable to probe %s early.\n",
1188 class_str, match->name);
1204 * early_platform_driver_probe - probe a class of registered drivers
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 * Used by architecture code to probe registered early platform drivers
1210 * within a certain class. For probe to happen a registered early platform
1211 * device matching a registered early platform driver is needed.
1213 int __init early_platform_driver_probe(char *class_str,
1220 for (i = -2; n < nr_probe; i++) {
1221 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1236 * early_platform_cleanup - clean up early platform code
1238 void __init early_platform_cleanup(void)
1240 struct platform_device *pd, *pd2;
1242 /* clean up the devres list used to chain devices */
1243 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1245 list_del(&pd->dev.devres_head);
1246 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));