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) {
95 ret = of_irq_get(dev->dev.of_node, num);
96 if (ret >= 0 || ret == -EPROBE_DEFER)
100 r = platform_get_resource(dev, IORESOURCE_IRQ, num);
102 return r ? r->start : -ENXIO;
105 EXPORT_SYMBOL_GPL(platform_get_irq);
108 * platform_get_resource_byname - get a resource for a device by name
109 * @dev: platform device
110 * @type: resource type
111 * @name: resource name
113 struct resource *platform_get_resource_byname(struct platform_device *dev,
119 for (i = 0; i < dev->num_resources; i++) {
120 struct resource *r = &dev->resource[i];
122 if (unlikely(!r->name))
125 if (type == resource_type(r) && !strcmp(r->name, name))
130 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
133 * platform_get_irq_byname - get an IRQ for a device by name
134 * @dev: platform device
137 int platform_get_irq_byname(struct platform_device *dev, const char *name)
139 struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
142 return r ? r->start : -ENXIO;
144 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
147 * platform_add_devices - add a numbers of platform devices
148 * @devs: array of platform devices to add
149 * @num: number of platform devices in array
151 int platform_add_devices(struct platform_device **devs, int num)
155 for (i = 0; i < num; i++) {
156 ret = platform_device_register(devs[i]);
159 platform_device_unregister(devs[i]);
166 EXPORT_SYMBOL_GPL(platform_add_devices);
168 struct platform_object {
169 struct platform_device pdev;
174 * platform_device_put - destroy a platform device
175 * @pdev: platform device to free
177 * Free all memory associated with a platform device. This function must
178 * _only_ be externally called in error cases. All other usage is a bug.
180 void platform_device_put(struct platform_device *pdev)
183 put_device(&pdev->dev);
185 EXPORT_SYMBOL_GPL(platform_device_put);
187 static void platform_device_release(struct device *dev)
189 struct platform_object *pa = container_of(dev, struct platform_object,
192 of_device_node_put(&pa->pdev.dev);
193 kfree(pa->pdev.dev.platform_data);
194 kfree(pa->pdev.mfd_cell);
195 kfree(pa->pdev.resource);
200 * platform_device_alloc - create a platform device
201 * @name: base name of the device we're adding
204 * Create a platform device object which can have other objects attached
205 * to it, and which will have attached objects freed when it is released.
207 struct platform_device *platform_device_alloc(const char *name, int id)
209 struct platform_object *pa;
211 pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
213 strcpy(pa->name, name);
214 pa->pdev.name = pa->name;
216 device_initialize(&pa->pdev.dev);
217 pa->pdev.dev.release = platform_device_release;
218 arch_setup_pdev_archdata(&pa->pdev);
221 return pa ? &pa->pdev : NULL;
223 EXPORT_SYMBOL_GPL(platform_device_alloc);
226 * platform_device_add_resources - add resources to a platform device
227 * @pdev: platform device allocated by platform_device_alloc to add resources to
228 * @res: set of resources that needs to be allocated for the device
229 * @num: number of resources
231 * Add a copy of the resources to the platform device. The memory
232 * associated with the resources will be freed when the platform device is
235 int platform_device_add_resources(struct platform_device *pdev,
236 const struct resource *res, unsigned int num)
238 struct resource *r = NULL;
241 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
246 kfree(pdev->resource);
248 pdev->num_resources = num;
251 EXPORT_SYMBOL_GPL(platform_device_add_resources);
254 * platform_device_add_data - add platform-specific data to a platform device
255 * @pdev: platform device allocated by platform_device_alloc to add resources to
256 * @data: platform specific data for this platform device
257 * @size: size of platform specific data
259 * Add a copy of platform specific data to the platform device's
260 * platform_data pointer. The memory associated with the platform data
261 * will be freed when the platform device is released.
263 int platform_device_add_data(struct platform_device *pdev, const void *data,
269 d = kmemdup(data, size, GFP_KERNEL);
274 kfree(pdev->dev.platform_data);
275 pdev->dev.platform_data = d;
278 EXPORT_SYMBOL_GPL(platform_device_add_data);
281 * platform_device_add - add a platform device to device hierarchy
282 * @pdev: platform device we're adding
284 * This is part 2 of platform_device_register(), though may be called
285 * separately _iff_ pdev was allocated by platform_device_alloc().
287 int platform_device_add(struct platform_device *pdev)
294 if (!pdev->dev.parent)
295 pdev->dev.parent = &platform_bus;
297 pdev->dev.bus = &platform_bus_type;
301 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
303 case PLATFORM_DEVID_NONE:
304 dev_set_name(&pdev->dev, "%s", pdev->name);
306 case PLATFORM_DEVID_AUTO:
308 * Automatically allocated device ID. We mark it as such so
309 * that we remember it must be freed, and we append a suffix
310 * to avoid namespace collision with explicit IDs.
312 ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
316 pdev->id_auto = true;
317 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
321 for (i = 0; i < pdev->num_resources; i++) {
322 struct resource *p, *r = &pdev->resource[i];
325 r->name = dev_name(&pdev->dev);
329 if (resource_type(r) == IORESOURCE_MEM)
331 else if (resource_type(r) == IORESOURCE_IO)
332 p = &ioport_resource;
335 if (p && insert_resource(p, r)) {
336 dev_err(&pdev->dev, "failed to claim resource %d\n", i);
342 pr_debug("Registering platform device '%s'. Parent at %s\n",
343 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
345 ret = device_add(&pdev->dev);
351 ida_simple_remove(&platform_devid_ida, pdev->id);
352 pdev->id = PLATFORM_DEVID_AUTO;
356 struct resource *r = &pdev->resource[i];
357 unsigned long type = resource_type(r);
359 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
366 EXPORT_SYMBOL_GPL(platform_device_add);
369 * platform_device_del - remove a platform-level device
370 * @pdev: platform device we're removing
372 * Note that this function will also release all memory- and port-based
373 * resources owned by the device (@dev->resource). This function must
374 * _only_ be externally called in error cases. All other usage is a bug.
376 void platform_device_del(struct platform_device *pdev)
381 device_del(&pdev->dev);
384 ida_simple_remove(&platform_devid_ida, pdev->id);
385 pdev->id = PLATFORM_DEVID_AUTO;
388 for (i = 0; i < pdev->num_resources; i++) {
389 struct resource *r = &pdev->resource[i];
390 unsigned long type = resource_type(r);
392 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
397 EXPORT_SYMBOL_GPL(platform_device_del);
400 * platform_device_register - add a platform-level device
401 * @pdev: platform device we're adding
403 int platform_device_register(struct platform_device *pdev)
405 device_initialize(&pdev->dev);
406 arch_setup_pdev_archdata(pdev);
407 return platform_device_add(pdev);
409 EXPORT_SYMBOL_GPL(platform_device_register);
412 * platform_device_unregister - unregister a platform-level device
413 * @pdev: platform device we're unregistering
415 * Unregistration is done in 2 steps. First we release all resources
416 * and remove it from the subsystem, then we drop reference count by
417 * calling platform_device_put().
419 void platform_device_unregister(struct platform_device *pdev)
421 platform_device_del(pdev);
422 platform_device_put(pdev);
424 EXPORT_SYMBOL_GPL(platform_device_unregister);
427 * platform_device_register_full - add a platform-level device with
428 * resources and platform-specific data
430 * @pdevinfo: data used to create device
432 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
434 struct platform_device *platform_device_register_full(
435 const struct platform_device_info *pdevinfo)
438 struct platform_device *pdev;
440 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
444 pdev->dev.parent = pdevinfo->parent;
445 ACPI_COMPANION_SET(&pdev->dev, pdevinfo->acpi_node.companion);
447 if (pdevinfo->dma_mask) {
449 * This memory isn't freed when the device is put,
450 * I don't have a nice idea for that though. Conceptually
451 * dma_mask in struct device should not be a pointer.
452 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
455 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
456 if (!pdev->dev.dma_mask)
459 *pdev->dev.dma_mask = pdevinfo->dma_mask;
460 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
463 ret = platform_device_add_resources(pdev,
464 pdevinfo->res, pdevinfo->num_res);
468 ret = platform_device_add_data(pdev,
469 pdevinfo->data, pdevinfo->size_data);
473 ret = platform_device_add(pdev);
476 ACPI_COMPANION_SET(&pdev->dev, NULL);
477 kfree(pdev->dev.dma_mask);
480 platform_device_put(pdev);
486 EXPORT_SYMBOL_GPL(platform_device_register_full);
488 static int platform_drv_probe(struct device *_dev)
490 struct platform_driver *drv = to_platform_driver(_dev->driver);
491 struct platform_device *dev = to_platform_device(_dev);
494 if (ACPI_HANDLE(_dev))
495 acpi_dev_pm_attach(_dev, true);
497 ret = drv->probe(dev);
498 if (ret && ACPI_HANDLE(_dev))
499 acpi_dev_pm_detach(_dev, true);
501 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
502 dev_warn(_dev, "probe deferral not supported\n");
509 static int platform_drv_probe_fail(struct device *_dev)
514 static int platform_drv_remove(struct device *_dev)
516 struct platform_driver *drv = to_platform_driver(_dev->driver);
517 struct platform_device *dev = to_platform_device(_dev);
520 ret = drv->remove(dev);
521 if (ACPI_HANDLE(_dev))
522 acpi_dev_pm_detach(_dev, true);
527 static void platform_drv_shutdown(struct device *_dev)
529 struct platform_driver *drv = to_platform_driver(_dev->driver);
530 struct platform_device *dev = to_platform_device(_dev);
533 if (ACPI_HANDLE(_dev))
534 acpi_dev_pm_detach(_dev, true);
538 * __platform_driver_register - register a driver for platform-level devices
539 * @drv: platform driver structure
540 * @owner: owning module/driver
542 int __platform_driver_register(struct platform_driver *drv,
543 struct module *owner)
545 drv->driver.owner = owner;
546 drv->driver.bus = &platform_bus_type;
548 drv->driver.probe = platform_drv_probe;
550 drv->driver.remove = platform_drv_remove;
552 drv->driver.shutdown = platform_drv_shutdown;
554 return driver_register(&drv->driver);
556 EXPORT_SYMBOL_GPL(__platform_driver_register);
559 * platform_driver_unregister - unregister a driver for platform-level devices
560 * @drv: platform driver structure
562 void platform_driver_unregister(struct platform_driver *drv)
564 driver_unregister(&drv->driver);
566 EXPORT_SYMBOL_GPL(platform_driver_unregister);
569 * platform_driver_probe - register driver for non-hotpluggable device
570 * @drv: platform driver structure
571 * @probe: the driver probe routine, probably from an __init section
573 * Use this instead of platform_driver_register() when you know the device
574 * is not hotpluggable and has already been registered, and you want to
575 * remove its run-once probe() infrastructure from memory after the driver
576 * has bound to the device.
578 * One typical use for this would be with drivers for controllers integrated
579 * into system-on-chip processors, where the controller devices have been
580 * configured as part of board setup.
582 * Note that this is incompatible with deferred probing.
584 * Returns zero if the driver registered and bound to a device, else returns
585 * a negative error code and with the driver not registered.
587 int __init_or_module platform_driver_probe(struct platform_driver *drv,
588 int (*probe)(struct platform_device *))
593 * Prevent driver from requesting probe deferral to avoid further
594 * futile probe attempts.
596 drv->prevent_deferred_probe = true;
598 /* make sure driver won't have bind/unbind attributes */
599 drv->driver.suppress_bind_attrs = true;
601 /* temporary section violation during probe() */
603 retval = code = platform_driver_register(drv);
606 * Fixup that section violation, being paranoid about code scanning
607 * the list of drivers in order to probe new devices. Check to see
608 * if the probe was successful, and make sure any forced probes of
611 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
613 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
615 drv->driver.probe = platform_drv_probe_fail;
616 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
619 platform_driver_unregister(drv);
622 EXPORT_SYMBOL_GPL(platform_driver_probe);
625 * platform_create_bundle - register driver and create corresponding device
626 * @driver: platform driver structure
627 * @probe: the driver probe routine, probably from an __init section
628 * @res: set of resources that needs to be allocated for the device
629 * @n_res: number of resources
630 * @data: platform specific data for this platform device
631 * @size: size of platform specific data
633 * Use this in legacy-style modules that probe hardware directly and
634 * register a single platform device and corresponding platform driver.
636 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
638 struct platform_device * __init_or_module platform_create_bundle(
639 struct platform_driver *driver,
640 int (*probe)(struct platform_device *),
641 struct resource *res, unsigned int n_res,
642 const void *data, size_t size)
644 struct platform_device *pdev;
647 pdev = platform_device_alloc(driver->driver.name, -1);
653 error = platform_device_add_resources(pdev, res, n_res);
657 error = platform_device_add_data(pdev, data, size);
661 error = platform_device_add(pdev);
665 error = platform_driver_probe(driver, probe);
672 platform_device_del(pdev);
674 platform_device_put(pdev);
676 return ERR_PTR(error);
678 EXPORT_SYMBOL_GPL(platform_create_bundle);
680 /* modalias support enables more hands-off userspace setup:
681 * (a) environment variable lets new-style hotplug events work once system is
682 * fully running: "modprobe $MODALIAS"
683 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
684 * mishandled before system is fully running: "modprobe $(cat modalias)"
686 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
689 struct platform_device *pdev = to_platform_device(dev);
692 len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
696 len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
700 len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
702 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
704 static DEVICE_ATTR_RO(modalias);
706 static struct attribute *platform_dev_attrs[] = {
707 &dev_attr_modalias.attr,
710 ATTRIBUTE_GROUPS(platform_dev);
712 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
714 struct platform_device *pdev = to_platform_device(dev);
717 /* Some devices have extra OF data and an OF-style MODALIAS */
718 rc = of_device_uevent_modalias(dev, env);
722 rc = acpi_device_uevent_modalias(dev, env);
726 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
731 static const struct platform_device_id *platform_match_id(
732 const struct platform_device_id *id,
733 struct platform_device *pdev)
735 while (id->name[0]) {
736 if (strcmp(pdev->name, id->name) == 0) {
746 * platform_match - bind platform device to platform driver.
750 * Platform device IDs are assumed to be encoded like this:
751 * "<name><instance>", where <name> is a short description of the type of
752 * device, like "pci" or "floppy", and <instance> is the enumerated
753 * instance of the device, like '0' or '42'. Driver IDs are simply
754 * "<name>". So, extract the <name> from the platform_device structure,
755 * and compare it against the name of the driver. Return whether they match
758 static int platform_match(struct device *dev, struct device_driver *drv)
760 struct platform_device *pdev = to_platform_device(dev);
761 struct platform_driver *pdrv = to_platform_driver(drv);
763 /* Attempt an OF style match first */
764 if (of_driver_match_device(dev, drv))
767 /* Then try ACPI style match */
768 if (acpi_driver_match_device(dev, drv))
771 /* Then try to match against the id table */
773 return platform_match_id(pdrv->id_table, pdev) != NULL;
775 /* fall-back to driver name match */
776 return (strcmp(pdev->name, drv->name) == 0);
779 #ifdef CONFIG_PM_SLEEP
781 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
783 struct platform_driver *pdrv = to_platform_driver(dev->driver);
784 struct platform_device *pdev = to_platform_device(dev);
787 if (dev->driver && pdrv->suspend)
788 ret = pdrv->suspend(pdev, mesg);
793 static int platform_legacy_resume(struct device *dev)
795 struct platform_driver *pdrv = to_platform_driver(dev->driver);
796 struct platform_device *pdev = to_platform_device(dev);
799 if (dev->driver && pdrv->resume)
800 ret = pdrv->resume(pdev);
805 #endif /* CONFIG_PM_SLEEP */
807 #ifdef CONFIG_SUSPEND
809 int platform_pm_suspend(struct device *dev)
811 struct device_driver *drv = dev->driver;
818 if (drv->pm->suspend)
819 ret = drv->pm->suspend(dev);
821 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
827 int platform_pm_resume(struct device *dev)
829 struct device_driver *drv = dev->driver;
837 ret = drv->pm->resume(dev);
839 ret = platform_legacy_resume(dev);
845 #endif /* CONFIG_SUSPEND */
847 #ifdef CONFIG_HIBERNATE_CALLBACKS
849 int platform_pm_freeze(struct device *dev)
851 struct device_driver *drv = dev->driver;
859 ret = drv->pm->freeze(dev);
861 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
867 int platform_pm_thaw(struct device *dev)
869 struct device_driver *drv = dev->driver;
877 ret = drv->pm->thaw(dev);
879 ret = platform_legacy_resume(dev);
885 int platform_pm_poweroff(struct device *dev)
887 struct device_driver *drv = dev->driver;
894 if (drv->pm->poweroff)
895 ret = drv->pm->poweroff(dev);
897 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
903 int platform_pm_restore(struct device *dev)
905 struct device_driver *drv = dev->driver;
912 if (drv->pm->restore)
913 ret = drv->pm->restore(dev);
915 ret = platform_legacy_resume(dev);
921 #endif /* CONFIG_HIBERNATE_CALLBACKS */
923 static const struct dev_pm_ops platform_dev_pm_ops = {
924 .runtime_suspend = pm_generic_runtime_suspend,
925 .runtime_resume = pm_generic_runtime_resume,
926 USE_PLATFORM_PM_SLEEP_OPS
929 struct bus_type platform_bus_type = {
931 .dev_groups = platform_dev_groups,
932 .match = platform_match,
933 .uevent = platform_uevent,
934 .pm = &platform_dev_pm_ops,
936 EXPORT_SYMBOL_GPL(platform_bus_type);
938 int __init platform_bus_init(void)
942 early_platform_cleanup();
944 error = device_register(&platform_bus);
947 error = bus_register(&platform_bus_type);
949 device_unregister(&platform_bus);
953 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
954 u64 dma_get_required_mask(struct device *dev)
956 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
957 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
960 if (!high_totalram) {
961 /* convert to mask just covering totalram */
962 low_totalram = (1 << (fls(low_totalram) - 1));
963 low_totalram += low_totalram - 1;
966 high_totalram = (1 << (fls(high_totalram) - 1));
967 high_totalram += high_totalram - 1;
968 mask = (((u64)high_totalram) << 32) + 0xffffffff;
972 EXPORT_SYMBOL_GPL(dma_get_required_mask);
975 static __initdata LIST_HEAD(early_platform_driver_list);
976 static __initdata LIST_HEAD(early_platform_device_list);
979 * early_platform_driver_register - register early platform driver
980 * @epdrv: early_platform driver structure
981 * @buf: string passed from early_param()
983 * Helper function for early_platform_init() / early_platform_init_buffer()
985 int __init early_platform_driver_register(struct early_platform_driver *epdrv,
991 /* Simply add the driver to the end of the global list.
992 * Drivers will by default be put on the list in compiled-in order.
994 if (!epdrv->list.next) {
995 INIT_LIST_HEAD(&epdrv->list);
996 list_add_tail(&epdrv->list, &early_platform_driver_list);
999 /* If the user has specified device then make sure the driver
1000 * gets prioritized. The driver of the last device specified on
1001 * command line will be put first on the list.
1003 n = strlen(epdrv->pdrv->driver.name);
1004 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1005 list_move(&epdrv->list, &early_platform_driver_list);
1007 /* Allow passing parameters after device name */
1008 if (buf[n] == '\0' || buf[n] == ',')
1009 epdrv->requested_id = -1;
1011 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1014 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1015 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1018 n += strcspn(&buf[n + 1], ",") + 1;
1024 if (epdrv->bufsize) {
1025 memcpy(epdrv->buffer, &buf[n],
1026 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1027 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1035 * early_platform_add_devices - adds a number of early platform devices
1036 * @devs: array of early platform devices to add
1037 * @num: number of early platform devices in array
1039 * Used by early architecture code to register early platform devices and
1040 * their platform data.
1042 void __init early_platform_add_devices(struct platform_device **devs, int num)
1047 /* simply add the devices to list */
1048 for (i = 0; i < num; i++) {
1049 dev = &devs[i]->dev;
1051 if (!dev->devres_head.next) {
1052 pm_runtime_early_init(dev);
1053 INIT_LIST_HEAD(&dev->devres_head);
1054 list_add_tail(&dev->devres_head,
1055 &early_platform_device_list);
1061 * early_platform_driver_register_all - register early platform drivers
1062 * @class_str: string to identify early platform driver class
1064 * Used by architecture code to register all early platform drivers
1065 * for a certain class. If omitted then only early platform drivers
1066 * with matching kernel command line class parameters will be registered.
1068 void __init early_platform_driver_register_all(char *class_str)
1070 /* The "class_str" parameter may or may not be present on the kernel
1071 * command line. If it is present then there may be more than one
1072 * matching parameter.
1074 * Since we register our early platform drivers using early_param()
1075 * we need to make sure that they also get registered in the case
1076 * when the parameter is missing from the kernel command line.
1078 * We use parse_early_options() to make sure the early_param() gets
1079 * called at least once. The early_param() may be called more than
1080 * once since the name of the preferred device may be specified on
1081 * the kernel command line. early_platform_driver_register() handles
1084 parse_early_options(class_str);
1088 * early_platform_match - find early platform device matching driver
1089 * @epdrv: early platform driver structure
1090 * @id: id to match against
1092 static struct platform_device * __init
1093 early_platform_match(struct early_platform_driver *epdrv, int id)
1095 struct platform_device *pd;
1097 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1098 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1106 * early_platform_left - check if early platform driver has matching devices
1107 * @epdrv: early platform driver structure
1108 * @id: return true if id or above exists
1110 static int __init early_platform_left(struct early_platform_driver *epdrv,
1113 struct platform_device *pd;
1115 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1116 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1124 * early_platform_driver_probe_id - probe drivers matching class_str and id
1125 * @class_str: string to identify early platform driver class
1126 * @id: id to match against
1127 * @nr_probe: number of platform devices to successfully probe before exiting
1129 static int __init early_platform_driver_probe_id(char *class_str,
1133 struct early_platform_driver *epdrv;
1134 struct platform_device *match;
1139 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1140 /* only use drivers matching our class_str */
1141 if (strcmp(class_str, epdrv->class_str))
1145 match_id = epdrv->requested_id;
1150 left += early_platform_left(epdrv, id);
1152 /* skip requested id */
1153 switch (epdrv->requested_id) {
1154 case EARLY_PLATFORM_ID_ERROR:
1155 case EARLY_PLATFORM_ID_UNSET:
1158 if (epdrv->requested_id == id)
1159 match_id = EARLY_PLATFORM_ID_UNSET;
1164 case EARLY_PLATFORM_ID_ERROR:
1165 pr_warn("%s: unable to parse %s parameter\n",
1166 class_str, epdrv->pdrv->driver.name);
1168 case EARLY_PLATFORM_ID_UNSET:
1172 match = early_platform_match(epdrv, match_id);
1177 * Set up a sensible init_name to enable
1178 * dev_name() and others to be used before the
1179 * rest of the driver core is initialized.
1181 if (!match->dev.init_name && slab_is_available()) {
1182 if (match->id != -1)
1183 match->dev.init_name =
1184 kasprintf(GFP_KERNEL, "%s.%d",
1188 match->dev.init_name =
1189 kasprintf(GFP_KERNEL, "%s",
1192 if (!match->dev.init_name)
1196 if (epdrv->pdrv->probe(match))
1197 pr_warn("%s: unable to probe %s early.\n",
1198 class_str, match->name);
1214 * early_platform_driver_probe - probe a class of registered drivers
1215 * @class_str: string to identify early platform driver class
1216 * @nr_probe: number of platform devices to successfully probe before exiting
1217 * @user_only: only probe user specified early platform devices
1219 * Used by architecture code to probe registered early platform drivers
1220 * within a certain class. For probe to happen a registered early platform
1221 * device matching a registered early platform driver is needed.
1223 int __init early_platform_driver_probe(char *class_str,
1230 for (i = -2; n < nr_probe; i++) {
1231 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1246 * early_platform_cleanup - clean up early platform code
1248 void __init early_platform_cleanup(void)
1250 struct platform_device *pd, *pd2;
1252 /* clean up the devres list used to chain devices */
1253 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1255 list_del(&pd->dev.devres_head);
1256 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));