1 // SPDX-License-Identifier: GPL-2.0
3 * platform.c - platform 'pseudo' bus for legacy devices
5 * Copyright (c) 2002-3 Patrick Mochel
6 * Copyright (c) 2002-3 Open Source Development Labs
8 * Please see Documentation/driver-model/platform.txt for more
12 #include <linux/string.h>
13 #include <linux/platform_device.h>
14 #include <linux/of_device.h>
15 #include <linux/of_irq.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/memblock.h>
20 #include <linux/err.h>
21 #include <linux/slab.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/pm_domain.h>
24 #include <linux/idr.h>
25 #include <linux/acpi.h>
26 #include <linux/clk/clk-conf.h>
27 #include <linux/limits.h>
28 #include <linux/property.h>
29 #include <linux/kmemleak.h>
32 #include "power/power.h"
34 /* For automatically allocated device IDs */
35 static DEFINE_IDA(platform_devid_ida);
37 struct device platform_bus = {
38 .init_name = "platform",
40 EXPORT_SYMBOL_GPL(platform_bus);
43 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
44 * @pdev: platform device
46 * This is called before platform_device_add() such that any pdev_archdata may
47 * be setup before the platform_notifier is called. So if a user needs to
48 * manipulate any relevant information in the pdev_archdata they can do:
50 * platform_device_alloc()
52 * platform_device_add()
54 * And if they don't care they can just call platform_device_register() and
55 * everything will just work out.
57 void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
62 * platform_get_resource - get a resource for a device
63 * @dev: platform device
64 * @type: resource type
65 * @num: resource index
67 struct resource *platform_get_resource(struct platform_device *dev,
68 unsigned int type, unsigned int num)
72 for (i = 0; i < dev->num_resources; i++) {
73 struct resource *r = &dev->resource[i];
75 if (type == resource_type(r) && num-- == 0)
80 EXPORT_SYMBOL_GPL(platform_get_resource);
83 * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
86 * @pdev: platform device to use both for memory resource lookup as well as
88 * @index: resource index
90 #ifdef CONFIG_HAS_IOMEM
91 void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
96 res = platform_get_resource(pdev, IORESOURCE_MEM, index);
97 return devm_ioremap_resource(&pdev->dev, res);
99 EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
100 #endif /* CONFIG_HAS_IOMEM */
103 * platform_get_irq - get an IRQ for a device
104 * @dev: platform device
105 * @num: IRQ number index
107 int platform_get_irq(struct platform_device *dev, unsigned int num)
110 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
111 if (!dev || num >= dev->archdata.num_irqs)
113 return dev->archdata.irqs[num];
116 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
119 ret = of_irq_get(dev->dev.of_node, num);
120 if (ret > 0 || ret == -EPROBE_DEFER)
124 r = platform_get_resource(dev, IORESOURCE_IRQ, num);
125 if (has_acpi_companion(&dev->dev)) {
126 if (r && r->flags & IORESOURCE_DISABLED) {
129 ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
136 * The resources may pass trigger flags to the irqs that need
137 * to be set up. It so happens that the trigger flags for
138 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
141 if (r && r->flags & IORESOURCE_BITS) {
142 struct irq_data *irqd;
144 irqd = irq_get_irq_data(r->start);
147 irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
154 * For the index 0 interrupt, allow falling back to GpioInt
155 * resources. While a device could have both Interrupt and GpioInt
156 * resources, making this fallback ambiguous, in many common cases
157 * the device will only expose one IRQ, and this fallback
158 * allows a common code path across either kind of resource.
160 if (num == 0 && has_acpi_companion(&dev->dev))
161 return acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
166 EXPORT_SYMBOL_GPL(platform_get_irq);
169 * platform_irq_count - Count the number of IRQs a platform device uses
170 * @dev: platform device
172 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
174 int platform_irq_count(struct platform_device *dev)
178 while ((ret = platform_get_irq(dev, nr)) >= 0)
181 if (ret == -EPROBE_DEFER)
186 EXPORT_SYMBOL_GPL(platform_irq_count);
189 * platform_get_resource_byname - get a resource for a device by name
190 * @dev: platform device
191 * @type: resource type
192 * @name: resource name
194 struct resource *platform_get_resource_byname(struct platform_device *dev,
200 for (i = 0; i < dev->num_resources; i++) {
201 struct resource *r = &dev->resource[i];
203 if (unlikely(!r->name))
206 if (type == resource_type(r) && !strcmp(r->name, name))
211 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
214 * platform_get_irq_byname - get an IRQ for a device by name
215 * @dev: platform device
218 int platform_get_irq_byname(struct platform_device *dev, const char *name)
222 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
225 ret = of_irq_get_byname(dev->dev.of_node, name);
226 if (ret > 0 || ret == -EPROBE_DEFER)
230 r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
231 return r ? r->start : -ENXIO;
233 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
236 * platform_add_devices - add a numbers of platform devices
237 * @devs: array of platform devices to add
238 * @num: number of platform devices in array
240 int platform_add_devices(struct platform_device **devs, int num)
244 for (i = 0; i < num; i++) {
245 ret = platform_device_register(devs[i]);
248 platform_device_unregister(devs[i]);
255 EXPORT_SYMBOL_GPL(platform_add_devices);
257 struct platform_object {
258 struct platform_device pdev;
263 * platform_device_put - destroy a platform device
264 * @pdev: platform device to free
266 * Free all memory associated with a platform device. This function must
267 * _only_ be externally called in error cases. All other usage is a bug.
269 void platform_device_put(struct platform_device *pdev)
271 if (!IS_ERR_OR_NULL(pdev))
272 put_device(&pdev->dev);
274 EXPORT_SYMBOL_GPL(platform_device_put);
276 static void platform_device_release(struct device *dev)
278 struct platform_object *pa = container_of(dev, struct platform_object,
281 of_device_node_put(&pa->pdev.dev);
282 kfree(pa->pdev.dev.platform_data);
283 kfree(pa->pdev.mfd_cell);
284 kfree(pa->pdev.resource);
285 kfree(pa->pdev.driver_override);
290 * platform_device_alloc - create a platform device
291 * @name: base name of the device we're adding
294 * Create a platform device object which can have other objects attached
295 * to it, and which will have attached objects freed when it is released.
297 struct platform_device *platform_device_alloc(const char *name, int id)
299 struct platform_object *pa;
301 pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
303 strcpy(pa->name, name);
304 pa->pdev.name = pa->name;
306 device_initialize(&pa->pdev.dev);
307 pa->pdev.dev.release = platform_device_release;
308 arch_setup_pdev_archdata(&pa->pdev);
311 return pa ? &pa->pdev : NULL;
313 EXPORT_SYMBOL_GPL(platform_device_alloc);
316 * platform_device_add_resources - add resources to a platform device
317 * @pdev: platform device allocated by platform_device_alloc to add resources to
318 * @res: set of resources that needs to be allocated for the device
319 * @num: number of resources
321 * Add a copy of the resources to the platform device. The memory
322 * associated with the resources will be freed when the platform device is
325 int platform_device_add_resources(struct platform_device *pdev,
326 const struct resource *res, unsigned int num)
328 struct resource *r = NULL;
331 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
336 kfree(pdev->resource);
338 pdev->num_resources = num;
341 EXPORT_SYMBOL_GPL(platform_device_add_resources);
344 * platform_device_add_data - add platform-specific data to a platform device
345 * @pdev: platform device allocated by platform_device_alloc to add resources to
346 * @data: platform specific data for this platform device
347 * @size: size of platform specific data
349 * Add a copy of platform specific data to the platform device's
350 * platform_data pointer. The memory associated with the platform data
351 * will be freed when the platform device is released.
353 int platform_device_add_data(struct platform_device *pdev, const void *data,
359 d = kmemdup(data, size, GFP_KERNEL);
364 kfree(pdev->dev.platform_data);
365 pdev->dev.platform_data = d;
368 EXPORT_SYMBOL_GPL(platform_device_add_data);
371 * platform_device_add_properties - add built-in properties to a platform device
372 * @pdev: platform device to add properties to
373 * @properties: null terminated array of properties to add
375 * The function will take deep copy of @properties and attach the copy to the
376 * platform device. The memory associated with properties will be freed when the
377 * platform device is released.
379 int platform_device_add_properties(struct platform_device *pdev,
380 const struct property_entry *properties)
382 return device_add_properties(&pdev->dev, properties);
384 EXPORT_SYMBOL_GPL(platform_device_add_properties);
387 * platform_device_add - add a platform device to device hierarchy
388 * @pdev: platform device we're adding
390 * This is part 2 of platform_device_register(), though may be called
391 * separately _iff_ pdev was allocated by platform_device_alloc().
393 int platform_device_add(struct platform_device *pdev)
400 if (!pdev->dev.parent)
401 pdev->dev.parent = &platform_bus;
403 pdev->dev.bus = &platform_bus_type;
407 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
409 case PLATFORM_DEVID_NONE:
410 dev_set_name(&pdev->dev, "%s", pdev->name);
412 case PLATFORM_DEVID_AUTO:
414 * Automatically allocated device ID. We mark it as such so
415 * that we remember it must be freed, and we append a suffix
416 * to avoid namespace collision with explicit IDs.
418 ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
422 pdev->id_auto = true;
423 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
427 for (i = 0; i < pdev->num_resources; i++) {
428 struct resource *p, *r = &pdev->resource[i];
431 r->name = dev_name(&pdev->dev);
435 if (resource_type(r) == IORESOURCE_MEM)
437 else if (resource_type(r) == IORESOURCE_IO)
438 p = &ioport_resource;
441 if (p && insert_resource(p, r)) {
442 dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
448 pr_debug("Registering platform device '%s'. Parent at %s\n",
449 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
451 ret = device_add(&pdev->dev);
457 ida_simple_remove(&platform_devid_ida, pdev->id);
458 pdev->id = PLATFORM_DEVID_AUTO;
462 struct resource *r = &pdev->resource[i];
470 EXPORT_SYMBOL_GPL(platform_device_add);
473 * platform_device_del - remove a platform-level device
474 * @pdev: platform device we're removing
476 * Note that this function will also release all memory- and port-based
477 * resources owned by the device (@dev->resource). This function must
478 * _only_ be externally called in error cases. All other usage is a bug.
480 void platform_device_del(struct platform_device *pdev)
484 if (!IS_ERR_OR_NULL(pdev)) {
485 device_del(&pdev->dev);
488 ida_simple_remove(&platform_devid_ida, pdev->id);
489 pdev->id = PLATFORM_DEVID_AUTO;
492 for (i = 0; i < pdev->num_resources; i++) {
493 struct resource *r = &pdev->resource[i];
499 EXPORT_SYMBOL_GPL(platform_device_del);
502 * platform_device_register - add a platform-level device
503 * @pdev: platform device we're adding
505 int platform_device_register(struct platform_device *pdev)
507 device_initialize(&pdev->dev);
508 arch_setup_pdev_archdata(pdev);
509 return platform_device_add(pdev);
511 EXPORT_SYMBOL_GPL(platform_device_register);
514 * platform_device_unregister - unregister a platform-level device
515 * @pdev: platform device we're unregistering
517 * Unregistration is done in 2 steps. First we release all resources
518 * and remove it from the subsystem, then we drop reference count by
519 * calling platform_device_put().
521 void platform_device_unregister(struct platform_device *pdev)
523 platform_device_del(pdev);
524 platform_device_put(pdev);
526 EXPORT_SYMBOL_GPL(platform_device_unregister);
529 * platform_device_register_full - add a platform-level device with
530 * resources and platform-specific data
532 * @pdevinfo: data used to create device
534 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
536 struct platform_device *platform_device_register_full(
537 const struct platform_device_info *pdevinfo)
540 struct platform_device *pdev;
542 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
544 return ERR_PTR(-ENOMEM);
546 pdev->dev.parent = pdevinfo->parent;
547 pdev->dev.fwnode = pdevinfo->fwnode;
548 pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
549 pdev->dev.of_node_reused = pdevinfo->of_node_reused;
551 if (pdevinfo->dma_mask) {
553 * This memory isn't freed when the device is put,
554 * I don't have a nice idea for that though. Conceptually
555 * dma_mask in struct device should not be a pointer.
556 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
559 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
560 if (!pdev->dev.dma_mask)
563 kmemleak_ignore(pdev->dev.dma_mask);
565 *pdev->dev.dma_mask = pdevinfo->dma_mask;
566 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
569 ret = platform_device_add_resources(pdev,
570 pdevinfo->res, pdevinfo->num_res);
574 ret = platform_device_add_data(pdev,
575 pdevinfo->data, pdevinfo->size_data);
579 if (pdevinfo->properties) {
580 ret = platform_device_add_properties(pdev,
581 pdevinfo->properties);
586 ret = platform_device_add(pdev);
589 ACPI_COMPANION_SET(&pdev->dev, NULL);
590 kfree(pdev->dev.dma_mask);
591 platform_device_put(pdev);
597 EXPORT_SYMBOL_GPL(platform_device_register_full);
599 static int platform_drv_probe(struct device *_dev)
601 struct platform_driver *drv = to_platform_driver(_dev->driver);
602 struct platform_device *dev = to_platform_device(_dev);
605 ret = of_clk_set_defaults(_dev->of_node, false);
609 ret = dev_pm_domain_attach(_dev, true);
614 ret = drv->probe(dev);
616 dev_pm_domain_detach(_dev, true);
620 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
621 dev_warn(_dev, "probe deferral not supported\n");
628 static int platform_drv_probe_fail(struct device *_dev)
633 static int platform_drv_remove(struct device *_dev)
635 struct platform_driver *drv = to_platform_driver(_dev->driver);
636 struct platform_device *dev = to_platform_device(_dev);
640 ret = drv->remove(dev);
641 dev_pm_domain_detach(_dev, true);
646 static void platform_drv_shutdown(struct device *_dev)
648 struct platform_driver *drv = to_platform_driver(_dev->driver);
649 struct platform_device *dev = to_platform_device(_dev);
656 * __platform_driver_register - register a driver for platform-level devices
657 * @drv: platform driver structure
658 * @owner: owning module/driver
660 int __platform_driver_register(struct platform_driver *drv,
661 struct module *owner)
663 drv->driver.owner = owner;
664 drv->driver.bus = &platform_bus_type;
665 drv->driver.probe = platform_drv_probe;
666 drv->driver.remove = platform_drv_remove;
667 drv->driver.shutdown = platform_drv_shutdown;
669 return driver_register(&drv->driver);
671 EXPORT_SYMBOL_GPL(__platform_driver_register);
674 * platform_driver_unregister - unregister a driver for platform-level devices
675 * @drv: platform driver structure
677 void platform_driver_unregister(struct platform_driver *drv)
679 driver_unregister(&drv->driver);
681 EXPORT_SYMBOL_GPL(platform_driver_unregister);
684 * __platform_driver_probe - register driver for non-hotpluggable device
685 * @drv: platform driver structure
686 * @probe: the driver probe routine, probably from an __init section
687 * @module: module which will be the owner of the driver
689 * Use this instead of platform_driver_register() when you know the device
690 * is not hotpluggable and has already been registered, and you want to
691 * remove its run-once probe() infrastructure from memory after the driver
692 * has bound to the device.
694 * One typical use for this would be with drivers for controllers integrated
695 * into system-on-chip processors, where the controller devices have been
696 * configured as part of board setup.
698 * Note that this is incompatible with deferred probing.
700 * Returns zero if the driver registered and bound to a device, else returns
701 * a negative error code and with the driver not registered.
703 int __init_or_module __platform_driver_probe(struct platform_driver *drv,
704 int (*probe)(struct platform_device *), struct module *module)
708 if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
709 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
710 drv->driver.name, __func__);
715 * We have to run our probes synchronously because we check if
716 * we find any devices to bind to and exit with error if there
719 drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
722 * Prevent driver from requesting probe deferral to avoid further
723 * futile probe attempts.
725 drv->prevent_deferred_probe = true;
727 /* make sure driver won't have bind/unbind attributes */
728 drv->driver.suppress_bind_attrs = true;
730 /* temporary section violation during probe() */
732 retval = code = __platform_driver_register(drv, module);
735 * Fixup that section violation, being paranoid about code scanning
736 * the list of drivers in order to probe new devices. Check to see
737 * if the probe was successful, and make sure any forced probes of
740 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
742 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
744 drv->driver.probe = platform_drv_probe_fail;
745 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
748 platform_driver_unregister(drv);
751 EXPORT_SYMBOL_GPL(__platform_driver_probe);
754 * __platform_create_bundle - register driver and create corresponding device
755 * @driver: platform driver structure
756 * @probe: the driver probe routine, probably from an __init section
757 * @res: set of resources that needs to be allocated for the device
758 * @n_res: number of resources
759 * @data: platform specific data for this platform device
760 * @size: size of platform specific data
761 * @module: module which will be the owner of the driver
763 * Use this in legacy-style modules that probe hardware directly and
764 * register a single platform device and corresponding platform driver.
766 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
768 struct platform_device * __init_or_module __platform_create_bundle(
769 struct platform_driver *driver,
770 int (*probe)(struct platform_device *),
771 struct resource *res, unsigned int n_res,
772 const void *data, size_t size, struct module *module)
774 struct platform_device *pdev;
777 pdev = platform_device_alloc(driver->driver.name, -1);
783 error = platform_device_add_resources(pdev, res, n_res);
787 error = platform_device_add_data(pdev, data, size);
791 error = platform_device_add(pdev);
795 error = __platform_driver_probe(driver, probe, module);
802 platform_device_del(pdev);
804 platform_device_put(pdev);
806 return ERR_PTR(error);
808 EXPORT_SYMBOL_GPL(__platform_create_bundle);
811 * __platform_register_drivers - register an array of platform drivers
812 * @drivers: an array of drivers to register
813 * @count: the number of drivers to register
814 * @owner: module owning the drivers
816 * Registers platform drivers specified by an array. On failure to register a
817 * driver, all previously registered drivers will be unregistered. Callers of
818 * this API should use platform_unregister_drivers() to unregister drivers in
821 * Returns: 0 on success or a negative error code on failure.
823 int __platform_register_drivers(struct platform_driver * const *drivers,
824 unsigned int count, struct module *owner)
829 for (i = 0; i < count; i++) {
830 pr_debug("registering platform driver %ps\n", drivers[i]);
832 err = __platform_driver_register(drivers[i], owner);
834 pr_err("failed to register platform driver %ps: %d\n",
844 pr_debug("unregistering platform driver %ps\n", drivers[i]);
845 platform_driver_unregister(drivers[i]);
850 EXPORT_SYMBOL_GPL(__platform_register_drivers);
853 * platform_unregister_drivers - unregister an array of platform drivers
854 * @drivers: an array of drivers to unregister
855 * @count: the number of drivers to unregister
857 * Unegisters platform drivers specified by an array. This is typically used
858 * to complement an earlier call to platform_register_drivers(). Drivers are
859 * unregistered in the reverse order in which they were registered.
861 void platform_unregister_drivers(struct platform_driver * const *drivers,
865 pr_debug("unregistering platform driver %ps\n", drivers[count]);
866 platform_driver_unregister(drivers[count]);
869 EXPORT_SYMBOL_GPL(platform_unregister_drivers);
871 /* modalias support enables more hands-off userspace setup:
872 * (a) environment variable lets new-style hotplug events work once system is
873 * fully running: "modprobe $MODALIAS"
874 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
875 * mishandled before system is fully running: "modprobe $(cat modalias)"
877 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
880 struct platform_device *pdev = to_platform_device(dev);
883 len = of_device_modalias(dev, buf, PAGE_SIZE);
887 len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
891 len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
893 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
895 static DEVICE_ATTR_RO(modalias);
897 static ssize_t driver_override_store(struct device *dev,
898 struct device_attribute *attr,
899 const char *buf, size_t count)
901 struct platform_device *pdev = to_platform_device(dev);
902 char *driver_override, *old, *cp;
904 /* We need to keep extra room for a newline */
905 if (count >= (PAGE_SIZE - 1))
908 driver_override = kstrndup(buf, count, GFP_KERNEL);
909 if (!driver_override)
912 cp = strchr(driver_override, '\n');
917 old = pdev->driver_override;
918 if (strlen(driver_override)) {
919 pdev->driver_override = driver_override;
921 kfree(driver_override);
922 pdev->driver_override = NULL;
931 static ssize_t driver_override_show(struct device *dev,
932 struct device_attribute *attr, char *buf)
934 struct platform_device *pdev = to_platform_device(dev);
938 len = sprintf(buf, "%s\n", pdev->driver_override);
942 static DEVICE_ATTR_RW(driver_override);
945 static struct attribute *platform_dev_attrs[] = {
946 &dev_attr_modalias.attr,
947 &dev_attr_driver_override.attr,
950 ATTRIBUTE_GROUPS(platform_dev);
952 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
954 struct platform_device *pdev = to_platform_device(dev);
957 /* Some devices have extra OF data and an OF-style MODALIAS */
958 rc = of_device_uevent_modalias(dev, env);
962 rc = acpi_device_uevent_modalias(dev, env);
966 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
971 static const struct platform_device_id *platform_match_id(
972 const struct platform_device_id *id,
973 struct platform_device *pdev)
975 while (id->name[0]) {
976 if (strcmp(pdev->name, id->name) == 0) {
986 * platform_match - bind platform device to platform driver.
990 * Platform device IDs are assumed to be encoded like this:
991 * "<name><instance>", where <name> is a short description of the type of
992 * device, like "pci" or "floppy", and <instance> is the enumerated
993 * instance of the device, like '0' or '42'. Driver IDs are simply
994 * "<name>". So, extract the <name> from the platform_device structure,
995 * and compare it against the name of the driver. Return whether they match
998 static int platform_match(struct device *dev, struct device_driver *drv)
1000 struct platform_device *pdev = to_platform_device(dev);
1001 struct platform_driver *pdrv = to_platform_driver(drv);
1003 /* When driver_override is set, only bind to the matching driver */
1004 if (pdev->driver_override)
1005 return !strcmp(pdev->driver_override, drv->name);
1007 /* Attempt an OF style match first */
1008 if (of_driver_match_device(dev, drv))
1011 /* Then try ACPI style match */
1012 if (acpi_driver_match_device(dev, drv))
1015 /* Then try to match against the id table */
1017 return platform_match_id(pdrv->id_table, pdev) != NULL;
1019 /* fall-back to driver name match */
1020 return (strcmp(pdev->name, drv->name) == 0);
1023 #ifdef CONFIG_PM_SLEEP
1025 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1027 struct platform_driver *pdrv = to_platform_driver(dev->driver);
1028 struct platform_device *pdev = to_platform_device(dev);
1031 if (dev->driver && pdrv->suspend)
1032 ret = pdrv->suspend(pdev, mesg);
1037 static int platform_legacy_resume(struct device *dev)
1039 struct platform_driver *pdrv = to_platform_driver(dev->driver);
1040 struct platform_device *pdev = to_platform_device(dev);
1043 if (dev->driver && pdrv->resume)
1044 ret = pdrv->resume(pdev);
1049 #endif /* CONFIG_PM_SLEEP */
1051 #ifdef CONFIG_SUSPEND
1053 int platform_pm_suspend(struct device *dev)
1055 struct device_driver *drv = dev->driver;
1062 if (drv->pm->suspend)
1063 ret = drv->pm->suspend(dev);
1065 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1071 int platform_pm_resume(struct device *dev)
1073 struct device_driver *drv = dev->driver;
1080 if (drv->pm->resume)
1081 ret = drv->pm->resume(dev);
1083 ret = platform_legacy_resume(dev);
1089 #endif /* CONFIG_SUSPEND */
1091 #ifdef CONFIG_HIBERNATE_CALLBACKS
1093 int platform_pm_freeze(struct device *dev)
1095 struct device_driver *drv = dev->driver;
1102 if (drv->pm->freeze)
1103 ret = drv->pm->freeze(dev);
1105 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1111 int platform_pm_thaw(struct device *dev)
1113 struct device_driver *drv = dev->driver;
1121 ret = drv->pm->thaw(dev);
1123 ret = platform_legacy_resume(dev);
1129 int platform_pm_poweroff(struct device *dev)
1131 struct device_driver *drv = dev->driver;
1138 if (drv->pm->poweroff)
1139 ret = drv->pm->poweroff(dev);
1141 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1147 int platform_pm_restore(struct device *dev)
1149 struct device_driver *drv = dev->driver;
1156 if (drv->pm->restore)
1157 ret = drv->pm->restore(dev);
1159 ret = platform_legacy_resume(dev);
1165 #endif /* CONFIG_HIBERNATE_CALLBACKS */
1167 int platform_dma_configure(struct device *dev)
1169 enum dev_dma_attr attr;
1173 ret = of_dma_configure(dev, dev->of_node, true);
1174 } else if (has_acpi_companion(dev)) {
1175 attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
1176 ret = acpi_dma_configure(dev, attr);
1182 static const struct dev_pm_ops platform_dev_pm_ops = {
1183 .runtime_suspend = pm_generic_runtime_suspend,
1184 .runtime_resume = pm_generic_runtime_resume,
1185 USE_PLATFORM_PM_SLEEP_OPS
1188 struct bus_type platform_bus_type = {
1190 .dev_groups = platform_dev_groups,
1191 .match = platform_match,
1192 .uevent = platform_uevent,
1193 .dma_configure = platform_dma_configure,
1194 .pm = &platform_dev_pm_ops,
1196 EXPORT_SYMBOL_GPL(platform_bus_type);
1198 int __init platform_bus_init(void)
1202 early_platform_cleanup();
1204 error = device_register(&platform_bus);
1206 put_device(&platform_bus);
1209 error = bus_register(&platform_bus_type);
1211 device_unregister(&platform_bus);
1212 of_platform_register_reconfig_notifier();
1216 static __initdata LIST_HEAD(early_platform_driver_list);
1217 static __initdata LIST_HEAD(early_platform_device_list);
1220 * early_platform_driver_register - register early platform driver
1221 * @epdrv: early_platform driver structure
1222 * @buf: string passed from early_param()
1224 * Helper function for early_platform_init() / early_platform_init_buffer()
1226 int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1232 /* Simply add the driver to the end of the global list.
1233 * Drivers will by default be put on the list in compiled-in order.
1235 if (!epdrv->list.next) {
1236 INIT_LIST_HEAD(&epdrv->list);
1237 list_add_tail(&epdrv->list, &early_platform_driver_list);
1240 /* If the user has specified device then make sure the driver
1241 * gets prioritized. The driver of the last device specified on
1242 * command line will be put first on the list.
1244 n = strlen(epdrv->pdrv->driver.name);
1245 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1246 list_move(&epdrv->list, &early_platform_driver_list);
1248 /* Allow passing parameters after device name */
1249 if (buf[n] == '\0' || buf[n] == ',')
1250 epdrv->requested_id = -1;
1252 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1255 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1256 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1259 n += strcspn(&buf[n + 1], ",") + 1;
1265 if (epdrv->bufsize) {
1266 memcpy(epdrv->buffer, &buf[n],
1267 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1268 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1276 * early_platform_add_devices - adds a number of early platform devices
1277 * @devs: array of early platform devices to add
1278 * @num: number of early platform devices in array
1280 * Used by early architecture code to register early platform devices and
1281 * their platform data.
1283 void __init early_platform_add_devices(struct platform_device **devs, int num)
1288 /* simply add the devices to list */
1289 for (i = 0; i < num; i++) {
1290 dev = &devs[i]->dev;
1292 if (!dev->devres_head.next) {
1293 pm_runtime_early_init(dev);
1294 INIT_LIST_HEAD(&dev->devres_head);
1295 list_add_tail(&dev->devres_head,
1296 &early_platform_device_list);
1302 * early_platform_driver_register_all - register early platform drivers
1303 * @class_str: string to identify early platform driver class
1305 * Used by architecture code to register all early platform drivers
1306 * for a certain class. If omitted then only early platform drivers
1307 * with matching kernel command line class parameters will be registered.
1309 void __init early_platform_driver_register_all(char *class_str)
1311 /* The "class_str" parameter may or may not be present on the kernel
1312 * command line. If it is present then there may be more than one
1313 * matching parameter.
1315 * Since we register our early platform drivers using early_param()
1316 * we need to make sure that they also get registered in the case
1317 * when the parameter is missing from the kernel command line.
1319 * We use parse_early_options() to make sure the early_param() gets
1320 * called at least once. The early_param() may be called more than
1321 * once since the name of the preferred device may be specified on
1322 * the kernel command line. early_platform_driver_register() handles
1325 parse_early_options(class_str);
1329 * early_platform_match - find early platform device matching driver
1330 * @epdrv: early platform driver structure
1331 * @id: id to match against
1333 static struct platform_device * __init
1334 early_platform_match(struct early_platform_driver *epdrv, int id)
1336 struct platform_device *pd;
1338 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1339 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1347 * early_platform_left - check if early platform driver has matching devices
1348 * @epdrv: early platform driver structure
1349 * @id: return true if id or above exists
1351 static int __init early_platform_left(struct early_platform_driver *epdrv,
1354 struct platform_device *pd;
1356 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1357 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1365 * early_platform_driver_probe_id - probe drivers matching class_str and id
1366 * @class_str: string to identify early platform driver class
1367 * @id: id to match against
1368 * @nr_probe: number of platform devices to successfully probe before exiting
1370 static int __init early_platform_driver_probe_id(char *class_str,
1374 struct early_platform_driver *epdrv;
1375 struct platform_device *match;
1380 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1381 /* only use drivers matching our class_str */
1382 if (strcmp(class_str, epdrv->class_str))
1386 match_id = epdrv->requested_id;
1391 left += early_platform_left(epdrv, id);
1393 /* skip requested id */
1394 switch (epdrv->requested_id) {
1395 case EARLY_PLATFORM_ID_ERROR:
1396 case EARLY_PLATFORM_ID_UNSET:
1399 if (epdrv->requested_id == id)
1400 match_id = EARLY_PLATFORM_ID_UNSET;
1405 case EARLY_PLATFORM_ID_ERROR:
1406 pr_warn("%s: unable to parse %s parameter\n",
1407 class_str, epdrv->pdrv->driver.name);
1409 case EARLY_PLATFORM_ID_UNSET:
1413 match = early_platform_match(epdrv, match_id);
1418 * Set up a sensible init_name to enable
1419 * dev_name() and others to be used before the
1420 * rest of the driver core is initialized.
1422 if (!match->dev.init_name && slab_is_available()) {
1423 if (match->id != -1)
1424 match->dev.init_name =
1425 kasprintf(GFP_KERNEL, "%s.%d",
1429 match->dev.init_name =
1430 kasprintf(GFP_KERNEL, "%s",
1433 if (!match->dev.init_name)
1437 if (epdrv->pdrv->probe(match))
1438 pr_warn("%s: unable to probe %s early.\n",
1439 class_str, match->name);
1455 * early_platform_driver_probe - probe a class of registered drivers
1456 * @class_str: string to identify early platform driver class
1457 * @nr_probe: number of platform devices to successfully probe before exiting
1458 * @user_only: only probe user specified early platform devices
1460 * Used by architecture code to probe registered early platform drivers
1461 * within a certain class. For probe to happen a registered early platform
1462 * device matching a registered early platform driver is needed.
1464 int __init early_platform_driver_probe(char *class_str,
1471 for (i = -2; n < nr_probe; i++) {
1472 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1487 * early_platform_cleanup - clean up early platform code
1489 void __init early_platform_cleanup(void)
1491 struct platform_device *pd, *pd2;
1493 /* clean up the devres list used to chain devices */
1494 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1496 list_del(&pd->dev.devres_head);
1497 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));