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/of_irq.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/bootmem.h>
21 #include <linux/err.h>
22 #include <linux/slab.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/idr.h>
25 #include <linux/acpi.h>
28 #include "power/power.h"
30 /* For automatically allocated device IDs */
31 static DEFINE_IDA(platform_devid_ida);
33 struct device platform_bus = {
34 .init_name = "platform",
36 EXPORT_SYMBOL_GPL(platform_bus);
39 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
40 * @pdev: platform device
42 * This is called before platform_device_add() such that any pdev_archdata may
43 * be setup before the platform_notifier is called. So if a user needs to
44 * manipulate any relevant information in the pdev_archdata they can do:
46 * platform_device_alloc()
48 * platform_device_add()
50 * And if they don't care they can just call platform_device_register() and
51 * everything will just work out.
53 void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
58 * platform_get_resource - get a resource for a device
59 * @dev: platform device
60 * @type: resource type
61 * @num: resource index
63 struct resource *platform_get_resource(struct platform_device *dev,
64 unsigned int type, unsigned int num)
68 for (i = 0; i < dev->num_resources; i++) {
69 struct resource *r = &dev->resource[i];
71 if (type == resource_type(r) && num-- == 0)
76 EXPORT_SYMBOL_GPL(platform_get_resource);
79 * platform_get_irq - get an IRQ for a device
80 * @dev: platform device
81 * @num: IRQ number index
83 int platform_get_irq(struct platform_device *dev, unsigned int num)
86 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
87 if (!dev || num >= dev->archdata.num_irqs)
89 return dev->archdata.irqs[num];
92 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node)
93 return of_irq_get(dev->dev.of_node, num);
95 r = platform_get_resource(dev, IORESOURCE_IRQ, num);
97 return r ? r->start : -ENXIO;
100 EXPORT_SYMBOL_GPL(platform_get_irq);
103 * platform_get_resource_byname - get a resource for a device by name
104 * @dev: platform device
105 * @type: resource type
106 * @name: resource name
108 struct resource *platform_get_resource_byname(struct platform_device *dev,
114 for (i = 0; i < dev->num_resources; i++) {
115 struct resource *r = &dev->resource[i];
117 if (unlikely(!r->name))
120 if (type == resource_type(r) && !strcmp(r->name, name))
125 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
128 * platform_get_irq_byname - get an IRQ for a device by name
129 * @dev: platform device
132 int platform_get_irq_byname(struct platform_device *dev, const char *name)
134 struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
137 return r ? r->start : -ENXIO;
139 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
142 * platform_add_devices - add a numbers of platform devices
143 * @devs: array of platform devices to add
144 * @num: number of platform devices in array
146 int platform_add_devices(struct platform_device **devs, int num)
150 for (i = 0; i < num; i++) {
151 ret = platform_device_register(devs[i]);
154 platform_device_unregister(devs[i]);
161 EXPORT_SYMBOL_GPL(platform_add_devices);
163 struct platform_object {
164 struct platform_device pdev;
169 * platform_device_put - destroy a platform device
170 * @pdev: platform device to free
172 * Free all memory associated with a platform device. This function must
173 * _only_ be externally called in error cases. All other usage is a bug.
175 void platform_device_put(struct platform_device *pdev)
178 put_device(&pdev->dev);
180 EXPORT_SYMBOL_GPL(platform_device_put);
182 static void platform_device_release(struct device *dev)
184 struct platform_object *pa = container_of(dev, struct platform_object,
187 of_device_node_put(&pa->pdev.dev);
188 kfree(pa->pdev.dev.platform_data);
189 kfree(pa->pdev.mfd_cell);
190 kfree(pa->pdev.resource);
195 * platform_device_alloc - create a platform device
196 * @name: base name of the device we're adding
199 * Create a platform device object which can have other objects attached
200 * to it, and which will have attached objects freed when it is released.
202 struct platform_device *platform_device_alloc(const char *name, int id)
204 struct platform_object *pa;
206 pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
208 strcpy(pa->name, name);
209 pa->pdev.name = pa->name;
211 device_initialize(&pa->pdev.dev);
212 pa->pdev.dev.release = platform_device_release;
213 arch_setup_pdev_archdata(&pa->pdev);
216 return pa ? &pa->pdev : NULL;
218 EXPORT_SYMBOL_GPL(platform_device_alloc);
221 * platform_device_add_resources - add resources to a platform device
222 * @pdev: platform device allocated by platform_device_alloc to add resources to
223 * @res: set of resources that needs to be allocated for the device
224 * @num: number of resources
226 * Add a copy of the resources to the platform device. The memory
227 * associated with the resources will be freed when the platform device is
230 int platform_device_add_resources(struct platform_device *pdev,
231 const struct resource *res, unsigned int num)
233 struct resource *r = NULL;
236 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
241 kfree(pdev->resource);
243 pdev->num_resources = num;
246 EXPORT_SYMBOL_GPL(platform_device_add_resources);
249 * platform_device_add_data - add platform-specific data to a platform device
250 * @pdev: platform device allocated by platform_device_alloc to add resources to
251 * @data: platform specific data for this platform device
252 * @size: size of platform specific data
254 * Add a copy of platform specific data to the platform device's
255 * platform_data pointer. The memory associated with the platform data
256 * will be freed when the platform device is released.
258 int platform_device_add_data(struct platform_device *pdev, const void *data,
264 d = kmemdup(data, size, GFP_KERNEL);
269 kfree(pdev->dev.platform_data);
270 pdev->dev.platform_data = d;
273 EXPORT_SYMBOL_GPL(platform_device_add_data);
276 * platform_device_add - add a platform device to device hierarchy
277 * @pdev: platform device we're adding
279 * This is part 2 of platform_device_register(), though may be called
280 * separately _iff_ pdev was allocated by platform_device_alloc().
282 int platform_device_add(struct platform_device *pdev)
289 if (!pdev->dev.parent)
290 pdev->dev.parent = &platform_bus;
292 pdev->dev.bus = &platform_bus_type;
296 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
298 case PLATFORM_DEVID_NONE:
299 dev_set_name(&pdev->dev, "%s", pdev->name);
301 case PLATFORM_DEVID_AUTO:
303 * Automatically allocated device ID. We mark it as such so
304 * that we remember it must be freed, and we append a suffix
305 * to avoid namespace collision with explicit IDs.
307 ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
311 pdev->id_auto = true;
312 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
316 for (i = 0; i < pdev->num_resources; i++) {
317 struct resource *p, *r = &pdev->resource[i];
320 r->name = dev_name(&pdev->dev);
324 if (resource_type(r) == IORESOURCE_MEM)
326 else if (resource_type(r) == IORESOURCE_IO)
327 p = &ioport_resource;
330 if (p && insert_resource(p, r)) {
331 dev_err(&pdev->dev, "failed to claim resource %d\n", i);
337 pr_debug("Registering platform device '%s'. Parent at %s\n",
338 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
340 ret = device_add(&pdev->dev);
346 ida_simple_remove(&platform_devid_ida, pdev->id);
347 pdev->id = PLATFORM_DEVID_AUTO;
351 struct resource *r = &pdev->resource[i];
352 unsigned long type = resource_type(r);
354 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
361 EXPORT_SYMBOL_GPL(platform_device_add);
364 * platform_device_del - remove a platform-level device
365 * @pdev: platform device we're removing
367 * Note that this function will also release all memory- and port-based
368 * resources owned by the device (@dev->resource). This function must
369 * _only_ be externally called in error cases. All other usage is a bug.
371 void platform_device_del(struct platform_device *pdev)
376 device_del(&pdev->dev);
379 ida_simple_remove(&platform_devid_ida, pdev->id);
380 pdev->id = PLATFORM_DEVID_AUTO;
383 for (i = 0; i < pdev->num_resources; i++) {
384 struct resource *r = &pdev->resource[i];
385 unsigned long type = resource_type(r);
387 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
392 EXPORT_SYMBOL_GPL(platform_device_del);
395 * platform_device_register - add a platform-level device
396 * @pdev: platform device we're adding
398 int platform_device_register(struct platform_device *pdev)
400 device_initialize(&pdev->dev);
401 arch_setup_pdev_archdata(pdev);
402 return platform_device_add(pdev);
404 EXPORT_SYMBOL_GPL(platform_device_register);
407 * platform_device_unregister - unregister a platform-level device
408 * @pdev: platform device we're unregistering
410 * Unregistration is done in 2 steps. First we release all resources
411 * and remove it from the subsystem, then we drop reference count by
412 * calling platform_device_put().
414 void platform_device_unregister(struct platform_device *pdev)
416 platform_device_del(pdev);
417 platform_device_put(pdev);
419 EXPORT_SYMBOL_GPL(platform_device_unregister);
422 * platform_device_register_full - add a platform-level device with
423 * resources and platform-specific data
425 * @pdevinfo: data used to create device
427 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
429 struct platform_device *platform_device_register_full(
430 const struct platform_device_info *pdevinfo)
433 struct platform_device *pdev;
435 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
439 pdev->dev.parent = pdevinfo->parent;
440 ACPI_COMPANION_SET(&pdev->dev, pdevinfo->acpi_node.companion);
442 if (pdevinfo->dma_mask) {
444 * This memory isn't freed when the device is put,
445 * I don't have a nice idea for that though. Conceptually
446 * dma_mask in struct device should not be a pointer.
447 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
450 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
451 if (!pdev->dev.dma_mask)
454 *pdev->dev.dma_mask = pdevinfo->dma_mask;
455 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
458 ret = platform_device_add_resources(pdev,
459 pdevinfo->res, pdevinfo->num_res);
463 ret = platform_device_add_data(pdev,
464 pdevinfo->data, pdevinfo->size_data);
468 ret = platform_device_add(pdev);
471 ACPI_COMPANION_SET(&pdev->dev, NULL);
472 kfree(pdev->dev.dma_mask);
475 platform_device_put(pdev);
481 EXPORT_SYMBOL_GPL(platform_device_register_full);
483 static int platform_drv_probe(struct device *_dev)
485 struct platform_driver *drv = to_platform_driver(_dev->driver);
486 struct platform_device *dev = to_platform_device(_dev);
489 acpi_dev_pm_attach(_dev, true);
491 ret = drv->probe(dev);
493 acpi_dev_pm_detach(_dev, true);
495 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
496 dev_warn(_dev, "probe deferral not supported\n");
503 static int platform_drv_probe_fail(struct device *_dev)
508 static int platform_drv_remove(struct device *_dev)
510 struct platform_driver *drv = to_platform_driver(_dev->driver);
511 struct platform_device *dev = to_platform_device(_dev);
514 ret = drv->remove(dev);
515 acpi_dev_pm_detach(_dev, true);
520 static void platform_drv_shutdown(struct device *_dev)
522 struct platform_driver *drv = to_platform_driver(_dev->driver);
523 struct platform_device *dev = to_platform_device(_dev);
526 acpi_dev_pm_detach(_dev, true);
530 * __platform_driver_register - register a driver for platform-level devices
531 * @drv: platform driver structure
532 * @owner: owning module/driver
534 int __platform_driver_register(struct platform_driver *drv,
535 struct module *owner)
537 drv->driver.owner = owner;
538 drv->driver.bus = &platform_bus_type;
540 drv->driver.probe = platform_drv_probe;
542 drv->driver.remove = platform_drv_remove;
544 drv->driver.shutdown = platform_drv_shutdown;
546 return driver_register(&drv->driver);
548 EXPORT_SYMBOL_GPL(__platform_driver_register);
551 * platform_driver_unregister - unregister a driver for platform-level devices
552 * @drv: platform driver structure
554 void platform_driver_unregister(struct platform_driver *drv)
556 driver_unregister(&drv->driver);
558 EXPORT_SYMBOL_GPL(platform_driver_unregister);
561 * platform_driver_probe - register driver for non-hotpluggable device
562 * @drv: platform driver structure
563 * @probe: the driver probe routine, probably from an __init section
565 * Use this instead of platform_driver_register() when you know the device
566 * is not hotpluggable and has already been registered, and you want to
567 * remove its run-once probe() infrastructure from memory after the driver
568 * has bound to the device.
570 * One typical use for this would be with drivers for controllers integrated
571 * into system-on-chip processors, where the controller devices have been
572 * configured as part of board setup.
574 * Note that this is incompatible with deferred probing.
576 * Returns zero if the driver registered and bound to a device, else returns
577 * a negative error code and with the driver not registered.
579 int __init_or_module platform_driver_probe(struct platform_driver *drv,
580 int (*probe)(struct platform_device *))
585 * Prevent driver from requesting probe deferral to avoid further
586 * futile probe attempts.
588 drv->prevent_deferred_probe = true;
590 /* make sure driver won't have bind/unbind attributes */
591 drv->driver.suppress_bind_attrs = true;
593 /* temporary section violation during probe() */
595 retval = code = platform_driver_register(drv);
598 * Fixup that section violation, being paranoid about code scanning
599 * the list of drivers in order to probe new devices. Check to see
600 * if the probe was successful, and make sure any forced probes of
603 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
605 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
607 drv->driver.probe = platform_drv_probe_fail;
608 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
611 platform_driver_unregister(drv);
614 EXPORT_SYMBOL_GPL(platform_driver_probe);
617 * platform_create_bundle - register driver and create corresponding device
618 * @driver: platform driver structure
619 * @probe: the driver probe routine, probably from an __init section
620 * @res: set of resources that needs to be allocated for the device
621 * @n_res: number of resources
622 * @data: platform specific data for this platform device
623 * @size: size of platform specific data
625 * Use this in legacy-style modules that probe hardware directly and
626 * register a single platform device and corresponding platform driver.
628 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
630 struct platform_device * __init_or_module platform_create_bundle(
631 struct platform_driver *driver,
632 int (*probe)(struct platform_device *),
633 struct resource *res, unsigned int n_res,
634 const void *data, size_t size)
636 struct platform_device *pdev;
639 pdev = platform_device_alloc(driver->driver.name, -1);
645 error = platform_device_add_resources(pdev, res, n_res);
649 error = platform_device_add_data(pdev, data, size);
653 error = platform_device_add(pdev);
657 error = platform_driver_probe(driver, probe);
664 platform_device_del(pdev);
666 platform_device_put(pdev);
668 return ERR_PTR(error);
670 EXPORT_SYMBOL_GPL(platform_create_bundle);
672 /* modalias support enables more hands-off userspace setup:
673 * (a) environment variable lets new-style hotplug events work once system is
674 * fully running: "modprobe $MODALIAS"
675 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
676 * mishandled before system is fully running: "modprobe $(cat modalias)"
678 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
681 struct platform_device *pdev = to_platform_device(dev);
684 len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
688 len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
692 len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
694 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
696 static DEVICE_ATTR_RO(modalias);
698 static struct attribute *platform_dev_attrs[] = {
699 &dev_attr_modalias.attr,
702 ATTRIBUTE_GROUPS(platform_dev);
704 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
706 struct platform_device *pdev = to_platform_device(dev);
709 /* Some devices have extra OF data and an OF-style MODALIAS */
710 rc = of_device_uevent_modalias(dev, env);
714 rc = acpi_device_uevent_modalias(dev, env);
718 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
723 static const struct platform_device_id *platform_match_id(
724 const struct platform_device_id *id,
725 struct platform_device *pdev)
727 while (id->name[0]) {
728 if (strcmp(pdev->name, id->name) == 0) {
738 * platform_match - bind platform device to platform driver.
742 * Platform device IDs are assumed to be encoded like this:
743 * "<name><instance>", where <name> is a short description of the type of
744 * device, like "pci" or "floppy", and <instance> is the enumerated
745 * instance of the device, like '0' or '42'. Driver IDs are simply
746 * "<name>". So, extract the <name> from the platform_device structure,
747 * and compare it against the name of the driver. Return whether they match
750 static int platform_match(struct device *dev, struct device_driver *drv)
752 struct platform_device *pdev = to_platform_device(dev);
753 struct platform_driver *pdrv = to_platform_driver(drv);
755 /* Attempt an OF style match first */
756 if (of_driver_match_device(dev, drv))
759 /* Then try ACPI style match */
760 if (acpi_driver_match_device(dev, drv))
763 /* Then try to match against the id table */
765 return platform_match_id(pdrv->id_table, pdev) != NULL;
767 /* fall-back to driver name match */
768 return (strcmp(pdev->name, drv->name) == 0);
771 #ifdef CONFIG_PM_SLEEP
773 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
775 struct platform_driver *pdrv = to_platform_driver(dev->driver);
776 struct platform_device *pdev = to_platform_device(dev);
779 if (dev->driver && pdrv->suspend)
780 ret = pdrv->suspend(pdev, mesg);
785 static int platform_legacy_resume(struct device *dev)
787 struct platform_driver *pdrv = to_platform_driver(dev->driver);
788 struct platform_device *pdev = to_platform_device(dev);
791 if (dev->driver && pdrv->resume)
792 ret = pdrv->resume(pdev);
797 #endif /* CONFIG_PM_SLEEP */
799 #ifdef CONFIG_SUSPEND
801 int platform_pm_suspend(struct device *dev)
803 struct device_driver *drv = dev->driver;
810 if (drv->pm->suspend)
811 ret = drv->pm->suspend(dev);
813 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
819 int platform_pm_resume(struct device *dev)
821 struct device_driver *drv = dev->driver;
829 ret = drv->pm->resume(dev);
831 ret = platform_legacy_resume(dev);
837 #endif /* CONFIG_SUSPEND */
839 #ifdef CONFIG_HIBERNATE_CALLBACKS
841 int platform_pm_freeze(struct device *dev)
843 struct device_driver *drv = dev->driver;
851 ret = drv->pm->freeze(dev);
853 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
859 int platform_pm_thaw(struct device *dev)
861 struct device_driver *drv = dev->driver;
869 ret = drv->pm->thaw(dev);
871 ret = platform_legacy_resume(dev);
877 int platform_pm_poweroff(struct device *dev)
879 struct device_driver *drv = dev->driver;
886 if (drv->pm->poweroff)
887 ret = drv->pm->poweroff(dev);
889 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
895 int platform_pm_restore(struct device *dev)
897 struct device_driver *drv = dev->driver;
904 if (drv->pm->restore)
905 ret = drv->pm->restore(dev);
907 ret = platform_legacy_resume(dev);
913 #endif /* CONFIG_HIBERNATE_CALLBACKS */
915 static const struct dev_pm_ops platform_dev_pm_ops = {
916 .runtime_suspend = pm_generic_runtime_suspend,
917 .runtime_resume = pm_generic_runtime_resume,
918 USE_PLATFORM_PM_SLEEP_OPS
921 struct bus_type platform_bus_type = {
923 .dev_groups = platform_dev_groups,
924 .match = platform_match,
925 .uevent = platform_uevent,
926 .pm = &platform_dev_pm_ops,
928 EXPORT_SYMBOL_GPL(platform_bus_type);
930 int __init platform_bus_init(void)
934 early_platform_cleanup();
936 error = device_register(&platform_bus);
939 error = bus_register(&platform_bus_type);
941 device_unregister(&platform_bus);
945 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
946 u64 dma_get_required_mask(struct device *dev)
948 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
949 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
952 if (!high_totalram) {
953 /* convert to mask just covering totalram */
954 low_totalram = (1 << (fls(low_totalram) - 1));
955 low_totalram += low_totalram - 1;
958 high_totalram = (1 << (fls(high_totalram) - 1));
959 high_totalram += high_totalram - 1;
960 mask = (((u64)high_totalram) << 32) + 0xffffffff;
964 EXPORT_SYMBOL_GPL(dma_get_required_mask);
967 static __initdata LIST_HEAD(early_platform_driver_list);
968 static __initdata LIST_HEAD(early_platform_device_list);
971 * early_platform_driver_register - register early platform driver
972 * @epdrv: early_platform driver structure
973 * @buf: string passed from early_param()
975 * Helper function for early_platform_init() / early_platform_init_buffer()
977 int __init early_platform_driver_register(struct early_platform_driver *epdrv,
983 /* Simply add the driver to the end of the global list.
984 * Drivers will by default be put on the list in compiled-in order.
986 if (!epdrv->list.next) {
987 INIT_LIST_HEAD(&epdrv->list);
988 list_add_tail(&epdrv->list, &early_platform_driver_list);
991 /* If the user has specified device then make sure the driver
992 * gets prioritized. The driver of the last device specified on
993 * command line will be put first on the list.
995 n = strlen(epdrv->pdrv->driver.name);
996 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
997 list_move(&epdrv->list, &early_platform_driver_list);
999 /* Allow passing parameters after device name */
1000 if (buf[n] == '\0' || buf[n] == ',')
1001 epdrv->requested_id = -1;
1003 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1006 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1007 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1010 n += strcspn(&buf[n + 1], ",") + 1;
1016 if (epdrv->bufsize) {
1017 memcpy(epdrv->buffer, &buf[n],
1018 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1019 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1027 * early_platform_add_devices - adds a number of early platform devices
1028 * @devs: array of early platform devices to add
1029 * @num: number of early platform devices in array
1031 * Used by early architecture code to register early platform devices and
1032 * their platform data.
1034 void __init early_platform_add_devices(struct platform_device **devs, int num)
1039 /* simply add the devices to list */
1040 for (i = 0; i < num; i++) {
1041 dev = &devs[i]->dev;
1043 if (!dev->devres_head.next) {
1044 pm_runtime_early_init(dev);
1045 INIT_LIST_HEAD(&dev->devres_head);
1046 list_add_tail(&dev->devres_head,
1047 &early_platform_device_list);
1053 * early_platform_driver_register_all - register early platform drivers
1054 * @class_str: string to identify early platform driver class
1056 * Used by architecture code to register all early platform drivers
1057 * for a certain class. If omitted then only early platform drivers
1058 * with matching kernel command line class parameters will be registered.
1060 void __init early_platform_driver_register_all(char *class_str)
1062 /* The "class_str" parameter may or may not be present on the kernel
1063 * command line. If it is present then there may be more than one
1064 * matching parameter.
1066 * Since we register our early platform drivers using early_param()
1067 * we need to make sure that they also get registered in the case
1068 * when the parameter is missing from the kernel command line.
1070 * We use parse_early_options() to make sure the early_param() gets
1071 * called at least once. The early_param() may be called more than
1072 * once since the name of the preferred device may be specified on
1073 * the kernel command line. early_platform_driver_register() handles
1076 parse_early_options(class_str);
1080 * early_platform_match - find early platform device matching driver
1081 * @epdrv: early platform driver structure
1082 * @id: id to match against
1084 static struct platform_device * __init
1085 early_platform_match(struct early_platform_driver *epdrv, int id)
1087 struct platform_device *pd;
1089 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1090 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1098 * early_platform_left - check if early platform driver has matching devices
1099 * @epdrv: early platform driver structure
1100 * @id: return true if id or above exists
1102 static int __init early_platform_left(struct early_platform_driver *epdrv,
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_driver_probe_id - probe drivers matching class_str and id
1117 * @class_str: string to identify early platform driver class
1118 * @id: id to match against
1119 * @nr_probe: number of platform devices to successfully probe before exiting
1121 static int __init early_platform_driver_probe_id(char *class_str,
1125 struct early_platform_driver *epdrv;
1126 struct platform_device *match;
1131 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1132 /* only use drivers matching our class_str */
1133 if (strcmp(class_str, epdrv->class_str))
1137 match_id = epdrv->requested_id;
1142 left += early_platform_left(epdrv, id);
1144 /* skip requested id */
1145 switch (epdrv->requested_id) {
1146 case EARLY_PLATFORM_ID_ERROR:
1147 case EARLY_PLATFORM_ID_UNSET:
1150 if (epdrv->requested_id == id)
1151 match_id = EARLY_PLATFORM_ID_UNSET;
1156 case EARLY_PLATFORM_ID_ERROR:
1157 pr_warn("%s: unable to parse %s parameter\n",
1158 class_str, epdrv->pdrv->driver.name);
1160 case EARLY_PLATFORM_ID_UNSET:
1164 match = early_platform_match(epdrv, match_id);
1169 * Set up a sensible init_name to enable
1170 * dev_name() and others to be used before the
1171 * rest of the driver core is initialized.
1173 if (!match->dev.init_name && slab_is_available()) {
1174 if (match->id != -1)
1175 match->dev.init_name =
1176 kasprintf(GFP_KERNEL, "%s.%d",
1180 match->dev.init_name =
1181 kasprintf(GFP_KERNEL, "%s",
1184 if (!match->dev.init_name)
1188 if (epdrv->pdrv->probe(match))
1189 pr_warn("%s: unable to probe %s early.\n",
1190 class_str, match->name);
1206 * early_platform_driver_probe - probe a class of registered drivers
1207 * @class_str: string to identify early platform driver class
1208 * @nr_probe: number of platform devices to successfully probe before exiting
1209 * @user_only: only probe user specified early platform devices
1211 * Used by architecture code to probe registered early platform drivers
1212 * within a certain class. For probe to happen a registered early platform
1213 * device matching a registered early platform driver is needed.
1215 int __init early_platform_driver_probe(char *class_str,
1222 for (i = -2; n < nr_probe; i++) {
1223 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1238 * early_platform_cleanup - clean up early platform code
1240 void __init early_platform_cleanup(void)
1242 struct platform_device *pd, *pd2;
1244 /* clean up the devres list used to chain devices */
1245 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1247 list_del(&pd->dev.devres_head);
1248 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));