x86/mm/pat: Don't report PAT on CPUs that don't support it
[linux/fpc-iii.git] / drivers / base / platform.c
blob493e03fa0e073c0b2ffad4a914aab0eab80bca53
1 /*
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
10 * information.
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/pm_domain.h>
25 #include <linux/idr.h>
26 #include <linux/acpi.h>
27 #include <linux/clk/clk-conf.h>
28 #include <linux/limits.h>
29 #include <linux/property.h>
31 #include "base.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);
42 /**
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()
51 * ... manipulate ...
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)
61 /**
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)
70 int i;
72 for (i = 0; i < dev->num_resources; i++) {
73 struct resource *r = &dev->resource[i];
75 if (type == resource_type(r) && num-- == 0)
76 return r;
78 return NULL;
80 EXPORT_SYMBOL_GPL(platform_get_resource);
82 /**
83 * platform_get_irq - get an IRQ for a device
84 * @dev: platform device
85 * @num: IRQ number index
87 int platform_get_irq(struct platform_device *dev, unsigned int num)
89 #ifdef CONFIG_SPARC
90 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
91 if (!dev || num >= dev->archdata.num_irqs)
92 return -ENXIO;
93 return dev->archdata.irqs[num];
94 #else
95 struct resource *r;
96 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
97 int ret;
99 ret = of_irq_get(dev->dev.of_node, num);
100 if (ret > 0 || ret == -EPROBE_DEFER)
101 return ret;
104 r = platform_get_resource(dev, IORESOURCE_IRQ, num);
105 if (has_acpi_companion(&dev->dev)) {
106 if (r && r->flags & IORESOURCE_DISABLED) {
107 int ret;
109 ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
110 if (ret)
111 return ret;
116 * The resources may pass trigger flags to the irqs that need
117 * to be set up. It so happens that the trigger flags for
118 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
119 * settings.
121 if (r && r->flags & IORESOURCE_BITS) {
122 struct irq_data *irqd;
124 irqd = irq_get_irq_data(r->start);
125 if (!irqd)
126 return -ENXIO;
127 irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
130 return r ? r->start : -ENXIO;
131 #endif
133 EXPORT_SYMBOL_GPL(platform_get_irq);
136 * platform_irq_count - Count the number of IRQs a platform device uses
137 * @dev: platform device
139 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
141 int platform_irq_count(struct platform_device *dev)
143 int ret, nr = 0;
145 while ((ret = platform_get_irq(dev, nr)) >= 0)
146 nr++;
148 if (ret == -EPROBE_DEFER)
149 return ret;
151 return nr;
153 EXPORT_SYMBOL_GPL(platform_irq_count);
156 * platform_get_resource_byname - get a resource for a device by name
157 * @dev: platform device
158 * @type: resource type
159 * @name: resource name
161 struct resource *platform_get_resource_byname(struct platform_device *dev,
162 unsigned int type,
163 const char *name)
165 int i;
167 for (i = 0; i < dev->num_resources; i++) {
168 struct resource *r = &dev->resource[i];
170 if (unlikely(!r->name))
171 continue;
173 if (type == resource_type(r) && !strcmp(r->name, name))
174 return r;
176 return NULL;
178 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
181 * platform_get_irq_byname - get an IRQ for a device by name
182 * @dev: platform device
183 * @name: IRQ name
185 int platform_get_irq_byname(struct platform_device *dev, const char *name)
187 struct resource *r;
189 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
190 int ret;
192 ret = of_irq_get_byname(dev->dev.of_node, name);
193 if (ret > 0 || ret == -EPROBE_DEFER)
194 return ret;
197 r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
198 return r ? r->start : -ENXIO;
200 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
203 * platform_add_devices - add a numbers of platform devices
204 * @devs: array of platform devices to add
205 * @num: number of platform devices in array
207 int platform_add_devices(struct platform_device **devs, int num)
209 int i, ret = 0;
211 for (i = 0; i < num; i++) {
212 ret = platform_device_register(devs[i]);
213 if (ret) {
214 while (--i >= 0)
215 platform_device_unregister(devs[i]);
216 break;
220 return ret;
222 EXPORT_SYMBOL_GPL(platform_add_devices);
224 struct platform_object {
225 struct platform_device pdev;
226 char name[];
230 * platform_device_put - destroy a platform device
231 * @pdev: platform device to free
233 * Free all memory associated with a platform device. This function must
234 * _only_ be externally called in error cases. All other usage is a bug.
236 void platform_device_put(struct platform_device *pdev)
238 if (pdev)
239 put_device(&pdev->dev);
241 EXPORT_SYMBOL_GPL(platform_device_put);
243 static void platform_device_release(struct device *dev)
245 struct platform_object *pa = container_of(dev, struct platform_object,
246 pdev.dev);
248 of_device_node_put(&pa->pdev.dev);
249 kfree(pa->pdev.dev.platform_data);
250 kfree(pa->pdev.mfd_cell);
251 kfree(pa->pdev.resource);
252 kfree(pa->pdev.driver_override);
253 kfree(pa);
257 * platform_device_alloc - create a platform device
258 * @name: base name of the device we're adding
259 * @id: instance id
261 * Create a platform device object which can have other objects attached
262 * to it, and which will have attached objects freed when it is released.
264 struct platform_device *platform_device_alloc(const char *name, int id)
266 struct platform_object *pa;
268 pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
269 if (pa) {
270 strcpy(pa->name, name);
271 pa->pdev.name = pa->name;
272 pa->pdev.id = id;
273 device_initialize(&pa->pdev.dev);
274 pa->pdev.dev.release = platform_device_release;
275 arch_setup_pdev_archdata(&pa->pdev);
278 return pa ? &pa->pdev : NULL;
280 EXPORT_SYMBOL_GPL(platform_device_alloc);
283 * platform_device_add_resources - add resources to a platform device
284 * @pdev: platform device allocated by platform_device_alloc to add resources to
285 * @res: set of resources that needs to be allocated for the device
286 * @num: number of resources
288 * Add a copy of the resources to the platform device. The memory
289 * associated with the resources will be freed when the platform device is
290 * released.
292 int platform_device_add_resources(struct platform_device *pdev,
293 const struct resource *res, unsigned int num)
295 struct resource *r = NULL;
297 if (res) {
298 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
299 if (!r)
300 return -ENOMEM;
303 kfree(pdev->resource);
304 pdev->resource = r;
305 pdev->num_resources = num;
306 return 0;
308 EXPORT_SYMBOL_GPL(platform_device_add_resources);
311 * platform_device_add_data - add platform-specific data to a platform device
312 * @pdev: platform device allocated by platform_device_alloc to add resources to
313 * @data: platform specific data for this platform device
314 * @size: size of platform specific data
316 * Add a copy of platform specific data to the platform device's
317 * platform_data pointer. The memory associated with the platform data
318 * will be freed when the platform device is released.
320 int platform_device_add_data(struct platform_device *pdev, const void *data,
321 size_t size)
323 void *d = NULL;
325 if (data) {
326 d = kmemdup(data, size, GFP_KERNEL);
327 if (!d)
328 return -ENOMEM;
331 kfree(pdev->dev.platform_data);
332 pdev->dev.platform_data = d;
333 return 0;
335 EXPORT_SYMBOL_GPL(platform_device_add_data);
338 * platform_device_add_properties - add built-in properties to a platform device
339 * @pdev: platform device to add properties to
340 * @properties: null terminated array of properties to add
342 * The function will take deep copy of @properties and attach the copy to the
343 * platform device. The memory associated with properties will be freed when the
344 * platform device is released.
346 int platform_device_add_properties(struct platform_device *pdev,
347 struct property_entry *properties)
349 return device_add_properties(&pdev->dev, properties);
351 EXPORT_SYMBOL_GPL(platform_device_add_properties);
354 * platform_device_add - add a platform device to device hierarchy
355 * @pdev: platform device we're adding
357 * This is part 2 of platform_device_register(), though may be called
358 * separately _iff_ pdev was allocated by platform_device_alloc().
360 int platform_device_add(struct platform_device *pdev)
362 int i, ret;
364 if (!pdev)
365 return -EINVAL;
367 if (!pdev->dev.parent)
368 pdev->dev.parent = &platform_bus;
370 pdev->dev.bus = &platform_bus_type;
372 switch (pdev->id) {
373 default:
374 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
375 break;
376 case PLATFORM_DEVID_NONE:
377 dev_set_name(&pdev->dev, "%s", pdev->name);
378 break;
379 case PLATFORM_DEVID_AUTO:
381 * Automatically allocated device ID. We mark it as such so
382 * that we remember it must be freed, and we append a suffix
383 * to avoid namespace collision with explicit IDs.
385 ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
386 if (ret < 0)
387 goto err_out;
388 pdev->id = ret;
389 pdev->id_auto = true;
390 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
391 break;
394 for (i = 0; i < pdev->num_resources; i++) {
395 struct resource *p, *r = &pdev->resource[i];
397 if (r->name == NULL)
398 r->name = dev_name(&pdev->dev);
400 p = r->parent;
401 if (!p) {
402 if (resource_type(r) == IORESOURCE_MEM)
403 p = &iomem_resource;
404 else if (resource_type(r) == IORESOURCE_IO)
405 p = &ioport_resource;
408 if (p && insert_resource(p, r)) {
409 dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
410 ret = -EBUSY;
411 goto failed;
415 pr_debug("Registering platform device '%s'. Parent at %s\n",
416 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
418 ret = device_add(&pdev->dev);
419 if (ret == 0)
420 return ret;
422 failed:
423 if (pdev->id_auto) {
424 ida_simple_remove(&platform_devid_ida, pdev->id);
425 pdev->id = PLATFORM_DEVID_AUTO;
428 while (--i >= 0) {
429 struct resource *r = &pdev->resource[i];
430 if (r->parent)
431 release_resource(r);
434 err_out:
435 return ret;
437 EXPORT_SYMBOL_GPL(platform_device_add);
440 * platform_device_del - remove a platform-level device
441 * @pdev: platform device we're removing
443 * Note that this function will also release all memory- and port-based
444 * resources owned by the device (@dev->resource). This function must
445 * _only_ be externally called in error cases. All other usage is a bug.
447 void platform_device_del(struct platform_device *pdev)
449 int i;
451 if (pdev) {
452 device_remove_properties(&pdev->dev);
453 device_del(&pdev->dev);
455 if (pdev->id_auto) {
456 ida_simple_remove(&platform_devid_ida, pdev->id);
457 pdev->id = PLATFORM_DEVID_AUTO;
460 for (i = 0; i < pdev->num_resources; i++) {
461 struct resource *r = &pdev->resource[i];
462 if (r->parent)
463 release_resource(r);
467 EXPORT_SYMBOL_GPL(platform_device_del);
470 * platform_device_register - add a platform-level device
471 * @pdev: platform device we're adding
473 int platform_device_register(struct platform_device *pdev)
475 device_initialize(&pdev->dev);
476 arch_setup_pdev_archdata(pdev);
477 return platform_device_add(pdev);
479 EXPORT_SYMBOL_GPL(platform_device_register);
482 * platform_device_unregister - unregister a platform-level device
483 * @pdev: platform device we're unregistering
485 * Unregistration is done in 2 steps. First we release all resources
486 * and remove it from the subsystem, then we drop reference count by
487 * calling platform_device_put().
489 void platform_device_unregister(struct platform_device *pdev)
491 platform_device_del(pdev);
492 platform_device_put(pdev);
494 EXPORT_SYMBOL_GPL(platform_device_unregister);
497 * platform_device_register_full - add a platform-level device with
498 * resources and platform-specific data
500 * @pdevinfo: data used to create device
502 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
504 struct platform_device *platform_device_register_full(
505 const struct platform_device_info *pdevinfo)
507 int ret = -ENOMEM;
508 struct platform_device *pdev;
510 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
511 if (!pdev)
512 goto err_alloc;
514 pdev->dev.parent = pdevinfo->parent;
515 pdev->dev.fwnode = pdevinfo->fwnode;
517 if (pdevinfo->dma_mask) {
519 * This memory isn't freed when the device is put,
520 * I don't have a nice idea for that though. Conceptually
521 * dma_mask in struct device should not be a pointer.
522 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
524 pdev->dev.dma_mask =
525 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
526 if (!pdev->dev.dma_mask)
527 goto err;
529 *pdev->dev.dma_mask = pdevinfo->dma_mask;
530 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
533 ret = platform_device_add_resources(pdev,
534 pdevinfo->res, pdevinfo->num_res);
535 if (ret)
536 goto err;
538 ret = platform_device_add_data(pdev,
539 pdevinfo->data, pdevinfo->size_data);
540 if (ret)
541 goto err;
543 if (pdevinfo->properties) {
544 ret = platform_device_add_properties(pdev,
545 pdevinfo->properties);
546 if (ret)
547 goto err;
550 ret = platform_device_add(pdev);
551 if (ret) {
552 err:
553 ACPI_COMPANION_SET(&pdev->dev, NULL);
554 kfree(pdev->dev.dma_mask);
556 err_alloc:
557 platform_device_put(pdev);
558 return ERR_PTR(ret);
561 return pdev;
563 EXPORT_SYMBOL_GPL(platform_device_register_full);
565 static int platform_drv_probe(struct device *_dev)
567 struct platform_driver *drv = to_platform_driver(_dev->driver);
568 struct platform_device *dev = to_platform_device(_dev);
569 int ret;
571 ret = of_clk_set_defaults(_dev->of_node, false);
572 if (ret < 0)
573 return ret;
575 ret = dev_pm_domain_attach(_dev, true);
576 if (ret != -EPROBE_DEFER) {
577 if (drv->probe) {
578 ret = drv->probe(dev);
579 if (ret)
580 dev_pm_domain_detach(_dev, true);
581 } else {
582 /* don't fail if just dev_pm_domain_attach failed */
583 ret = 0;
587 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
588 dev_warn(_dev, "probe deferral not supported\n");
589 ret = -ENXIO;
592 return ret;
595 static int platform_drv_probe_fail(struct device *_dev)
597 return -ENXIO;
600 static int platform_drv_remove(struct device *_dev)
602 struct platform_driver *drv = to_platform_driver(_dev->driver);
603 struct platform_device *dev = to_platform_device(_dev);
604 int ret = 0;
606 if (drv->remove)
607 ret = drv->remove(dev);
608 dev_pm_domain_detach(_dev, true);
610 return ret;
613 static void platform_drv_shutdown(struct device *_dev)
615 struct platform_driver *drv = to_platform_driver(_dev->driver);
616 struct platform_device *dev = to_platform_device(_dev);
618 if (drv->shutdown)
619 drv->shutdown(dev);
623 * __platform_driver_register - register a driver for platform-level devices
624 * @drv: platform driver structure
625 * @owner: owning module/driver
627 int __platform_driver_register(struct platform_driver *drv,
628 struct module *owner)
630 drv->driver.owner = owner;
631 drv->driver.bus = &platform_bus_type;
632 drv->driver.probe = platform_drv_probe;
633 drv->driver.remove = platform_drv_remove;
634 drv->driver.shutdown = platform_drv_shutdown;
636 return driver_register(&drv->driver);
638 EXPORT_SYMBOL_GPL(__platform_driver_register);
641 * platform_driver_unregister - unregister a driver for platform-level devices
642 * @drv: platform driver structure
644 void platform_driver_unregister(struct platform_driver *drv)
646 driver_unregister(&drv->driver);
648 EXPORT_SYMBOL_GPL(platform_driver_unregister);
651 * __platform_driver_probe - register driver for non-hotpluggable device
652 * @drv: platform driver structure
653 * @probe: the driver probe routine, probably from an __init section
654 * @module: module which will be the owner of the driver
656 * Use this instead of platform_driver_register() when you know the device
657 * is not hotpluggable and has already been registered, and you want to
658 * remove its run-once probe() infrastructure from memory after the driver
659 * has bound to the device.
661 * One typical use for this would be with drivers for controllers integrated
662 * into system-on-chip processors, where the controller devices have been
663 * configured as part of board setup.
665 * Note that this is incompatible with deferred probing.
667 * Returns zero if the driver registered and bound to a device, else returns
668 * a negative error code and with the driver not registered.
670 int __init_or_module __platform_driver_probe(struct platform_driver *drv,
671 int (*probe)(struct platform_device *), struct module *module)
673 int retval, code;
675 if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
676 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
677 drv->driver.name, __func__);
678 return -EINVAL;
682 * We have to run our probes synchronously because we check if
683 * we find any devices to bind to and exit with error if there
684 * are any.
686 drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
689 * Prevent driver from requesting probe deferral to avoid further
690 * futile probe attempts.
692 drv->prevent_deferred_probe = true;
694 /* make sure driver won't have bind/unbind attributes */
695 drv->driver.suppress_bind_attrs = true;
697 /* temporary section violation during probe() */
698 drv->probe = probe;
699 retval = code = __platform_driver_register(drv, module);
702 * Fixup that section violation, being paranoid about code scanning
703 * the list of drivers in order to probe new devices. Check to see
704 * if the probe was successful, and make sure any forced probes of
705 * new devices fail.
707 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
708 drv->probe = NULL;
709 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
710 retval = -ENODEV;
711 drv->driver.probe = platform_drv_probe_fail;
712 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
714 if (code != retval)
715 platform_driver_unregister(drv);
716 return retval;
718 EXPORT_SYMBOL_GPL(__platform_driver_probe);
721 * __platform_create_bundle - register driver and create corresponding device
722 * @driver: platform driver structure
723 * @probe: the driver probe routine, probably from an __init section
724 * @res: set of resources that needs to be allocated for the device
725 * @n_res: number of resources
726 * @data: platform specific data for this platform device
727 * @size: size of platform specific data
728 * @module: module which will be the owner of the driver
730 * Use this in legacy-style modules that probe hardware directly and
731 * register a single platform device and corresponding platform driver.
733 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
735 struct platform_device * __init_or_module __platform_create_bundle(
736 struct platform_driver *driver,
737 int (*probe)(struct platform_device *),
738 struct resource *res, unsigned int n_res,
739 const void *data, size_t size, struct module *module)
741 struct platform_device *pdev;
742 int error;
744 pdev = platform_device_alloc(driver->driver.name, -1);
745 if (!pdev) {
746 error = -ENOMEM;
747 goto err_out;
750 error = platform_device_add_resources(pdev, res, n_res);
751 if (error)
752 goto err_pdev_put;
754 error = platform_device_add_data(pdev, data, size);
755 if (error)
756 goto err_pdev_put;
758 error = platform_device_add(pdev);
759 if (error)
760 goto err_pdev_put;
762 error = __platform_driver_probe(driver, probe, module);
763 if (error)
764 goto err_pdev_del;
766 return pdev;
768 err_pdev_del:
769 platform_device_del(pdev);
770 err_pdev_put:
771 platform_device_put(pdev);
772 err_out:
773 return ERR_PTR(error);
775 EXPORT_SYMBOL_GPL(__platform_create_bundle);
778 * __platform_register_drivers - register an array of platform drivers
779 * @drivers: an array of drivers to register
780 * @count: the number of drivers to register
781 * @owner: module owning the drivers
783 * Registers platform drivers specified by an array. On failure to register a
784 * driver, all previously registered drivers will be unregistered. Callers of
785 * this API should use platform_unregister_drivers() to unregister drivers in
786 * the reverse order.
788 * Returns: 0 on success or a negative error code on failure.
790 int __platform_register_drivers(struct platform_driver * const *drivers,
791 unsigned int count, struct module *owner)
793 unsigned int i;
794 int err;
796 for (i = 0; i < count; i++) {
797 pr_debug("registering platform driver %ps\n", drivers[i]);
799 err = __platform_driver_register(drivers[i], owner);
800 if (err < 0) {
801 pr_err("failed to register platform driver %ps: %d\n",
802 drivers[i], err);
803 goto error;
807 return 0;
809 error:
810 while (i--) {
811 pr_debug("unregistering platform driver %ps\n", drivers[i]);
812 platform_driver_unregister(drivers[i]);
815 return err;
817 EXPORT_SYMBOL_GPL(__platform_register_drivers);
820 * platform_unregister_drivers - unregister an array of platform drivers
821 * @drivers: an array of drivers to unregister
822 * @count: the number of drivers to unregister
824 * Unegisters platform drivers specified by an array. This is typically used
825 * to complement an earlier call to platform_register_drivers(). Drivers are
826 * unregistered in the reverse order in which they were registered.
828 void platform_unregister_drivers(struct platform_driver * const *drivers,
829 unsigned int count)
831 while (count--) {
832 pr_debug("unregistering platform driver %ps\n", drivers[count]);
833 platform_driver_unregister(drivers[count]);
836 EXPORT_SYMBOL_GPL(platform_unregister_drivers);
838 /* modalias support enables more hands-off userspace setup:
839 * (a) environment variable lets new-style hotplug events work once system is
840 * fully running: "modprobe $MODALIAS"
841 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
842 * mishandled before system is fully running: "modprobe $(cat modalias)"
844 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
845 char *buf)
847 struct platform_device *pdev = to_platform_device(dev);
848 int len;
850 len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
851 if (len != -ENODEV)
852 return len;
854 len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
855 if (len != -ENODEV)
856 return len;
858 len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
860 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
862 static DEVICE_ATTR_RO(modalias);
864 static ssize_t driver_override_store(struct device *dev,
865 struct device_attribute *attr,
866 const char *buf, size_t count)
868 struct platform_device *pdev = to_platform_device(dev);
869 char *driver_override, *old, *cp;
871 if (count > PATH_MAX)
872 return -EINVAL;
874 driver_override = kstrndup(buf, count, GFP_KERNEL);
875 if (!driver_override)
876 return -ENOMEM;
878 cp = strchr(driver_override, '\n');
879 if (cp)
880 *cp = '\0';
882 device_lock(dev);
883 old = pdev->driver_override;
884 if (strlen(driver_override)) {
885 pdev->driver_override = driver_override;
886 } else {
887 kfree(driver_override);
888 pdev->driver_override = NULL;
890 device_unlock(dev);
892 kfree(old);
894 return count;
897 static ssize_t driver_override_show(struct device *dev,
898 struct device_attribute *attr, char *buf)
900 struct platform_device *pdev = to_platform_device(dev);
901 ssize_t len;
903 device_lock(dev);
904 len = sprintf(buf, "%s\n", pdev->driver_override);
905 device_unlock(dev);
906 return len;
908 static DEVICE_ATTR_RW(driver_override);
911 static struct attribute *platform_dev_attrs[] = {
912 &dev_attr_modalias.attr,
913 &dev_attr_driver_override.attr,
914 NULL,
916 ATTRIBUTE_GROUPS(platform_dev);
918 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
920 struct platform_device *pdev = to_platform_device(dev);
921 int rc;
923 /* Some devices have extra OF data and an OF-style MODALIAS */
924 rc = of_device_uevent_modalias(dev, env);
925 if (rc != -ENODEV)
926 return rc;
928 rc = acpi_device_uevent_modalias(dev, env);
929 if (rc != -ENODEV)
930 return rc;
932 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
933 pdev->name);
934 return 0;
937 static const struct platform_device_id *platform_match_id(
938 const struct platform_device_id *id,
939 struct platform_device *pdev)
941 while (id->name[0]) {
942 if (strcmp(pdev->name, id->name) == 0) {
943 pdev->id_entry = id;
944 return id;
946 id++;
948 return NULL;
952 * platform_match - bind platform device to platform driver.
953 * @dev: device.
954 * @drv: driver.
956 * Platform device IDs are assumed to be encoded like this:
957 * "<name><instance>", where <name> is a short description of the type of
958 * device, like "pci" or "floppy", and <instance> is the enumerated
959 * instance of the device, like '0' or '42'. Driver IDs are simply
960 * "<name>". So, extract the <name> from the platform_device structure,
961 * and compare it against the name of the driver. Return whether they match
962 * or not.
964 static int platform_match(struct device *dev, struct device_driver *drv)
966 struct platform_device *pdev = to_platform_device(dev);
967 struct platform_driver *pdrv = to_platform_driver(drv);
969 /* When driver_override is set, only bind to the matching driver */
970 if (pdev->driver_override)
971 return !strcmp(pdev->driver_override, drv->name);
973 /* Attempt an OF style match first */
974 if (of_driver_match_device(dev, drv))
975 return 1;
977 /* Then try ACPI style match */
978 if (acpi_driver_match_device(dev, drv))
979 return 1;
981 /* Then try to match against the id table */
982 if (pdrv->id_table)
983 return platform_match_id(pdrv->id_table, pdev) != NULL;
985 /* fall-back to driver name match */
986 return (strcmp(pdev->name, drv->name) == 0);
989 #ifdef CONFIG_PM_SLEEP
991 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
993 struct platform_driver *pdrv = to_platform_driver(dev->driver);
994 struct platform_device *pdev = to_platform_device(dev);
995 int ret = 0;
997 if (dev->driver && pdrv->suspend)
998 ret = pdrv->suspend(pdev, mesg);
1000 return ret;
1003 static int platform_legacy_resume(struct device *dev)
1005 struct platform_driver *pdrv = to_platform_driver(dev->driver);
1006 struct platform_device *pdev = to_platform_device(dev);
1007 int ret = 0;
1009 if (dev->driver && pdrv->resume)
1010 ret = pdrv->resume(pdev);
1012 return ret;
1015 #endif /* CONFIG_PM_SLEEP */
1017 #ifdef CONFIG_SUSPEND
1019 int platform_pm_suspend(struct device *dev)
1021 struct device_driver *drv = dev->driver;
1022 int ret = 0;
1024 if (!drv)
1025 return 0;
1027 if (drv->pm) {
1028 if (drv->pm->suspend)
1029 ret = drv->pm->suspend(dev);
1030 } else {
1031 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1034 return ret;
1037 int platform_pm_resume(struct device *dev)
1039 struct device_driver *drv = dev->driver;
1040 int ret = 0;
1042 if (!drv)
1043 return 0;
1045 if (drv->pm) {
1046 if (drv->pm->resume)
1047 ret = drv->pm->resume(dev);
1048 } else {
1049 ret = platform_legacy_resume(dev);
1052 return ret;
1055 #endif /* CONFIG_SUSPEND */
1057 #ifdef CONFIG_HIBERNATE_CALLBACKS
1059 int platform_pm_freeze(struct device *dev)
1061 struct device_driver *drv = dev->driver;
1062 int ret = 0;
1064 if (!drv)
1065 return 0;
1067 if (drv->pm) {
1068 if (drv->pm->freeze)
1069 ret = drv->pm->freeze(dev);
1070 } else {
1071 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1074 return ret;
1077 int platform_pm_thaw(struct device *dev)
1079 struct device_driver *drv = dev->driver;
1080 int ret = 0;
1082 if (!drv)
1083 return 0;
1085 if (drv->pm) {
1086 if (drv->pm->thaw)
1087 ret = drv->pm->thaw(dev);
1088 } else {
1089 ret = platform_legacy_resume(dev);
1092 return ret;
1095 int platform_pm_poweroff(struct device *dev)
1097 struct device_driver *drv = dev->driver;
1098 int ret = 0;
1100 if (!drv)
1101 return 0;
1103 if (drv->pm) {
1104 if (drv->pm->poweroff)
1105 ret = drv->pm->poweroff(dev);
1106 } else {
1107 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1110 return ret;
1113 int platform_pm_restore(struct device *dev)
1115 struct device_driver *drv = dev->driver;
1116 int ret = 0;
1118 if (!drv)
1119 return 0;
1121 if (drv->pm) {
1122 if (drv->pm->restore)
1123 ret = drv->pm->restore(dev);
1124 } else {
1125 ret = platform_legacy_resume(dev);
1128 return ret;
1131 #endif /* CONFIG_HIBERNATE_CALLBACKS */
1133 static const struct dev_pm_ops platform_dev_pm_ops = {
1134 .runtime_suspend = pm_generic_runtime_suspend,
1135 .runtime_resume = pm_generic_runtime_resume,
1136 USE_PLATFORM_PM_SLEEP_OPS
1139 struct bus_type platform_bus_type = {
1140 .name = "platform",
1141 .dev_groups = platform_dev_groups,
1142 .match = platform_match,
1143 .uevent = platform_uevent,
1144 .pm = &platform_dev_pm_ops,
1146 EXPORT_SYMBOL_GPL(platform_bus_type);
1148 int __init platform_bus_init(void)
1150 int error;
1152 early_platform_cleanup();
1154 error = device_register(&platform_bus);
1155 if (error)
1156 return error;
1157 error = bus_register(&platform_bus_type);
1158 if (error)
1159 device_unregister(&platform_bus);
1160 of_platform_register_reconfig_notifier();
1161 return error;
1164 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1165 u64 dma_get_required_mask(struct device *dev)
1167 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
1168 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1169 u64 mask;
1171 if (!high_totalram) {
1172 /* convert to mask just covering totalram */
1173 low_totalram = (1 << (fls(low_totalram) - 1));
1174 low_totalram += low_totalram - 1;
1175 mask = low_totalram;
1176 } else {
1177 high_totalram = (1 << (fls(high_totalram) - 1));
1178 high_totalram += high_totalram - 1;
1179 mask = (((u64)high_totalram) << 32) + 0xffffffff;
1181 return mask;
1183 EXPORT_SYMBOL_GPL(dma_get_required_mask);
1184 #endif
1186 static __initdata LIST_HEAD(early_platform_driver_list);
1187 static __initdata LIST_HEAD(early_platform_device_list);
1190 * early_platform_driver_register - register early platform driver
1191 * @epdrv: early_platform driver structure
1192 * @buf: string passed from early_param()
1194 * Helper function for early_platform_init() / early_platform_init_buffer()
1196 int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1197 char *buf)
1199 char *tmp;
1200 int n;
1202 /* Simply add the driver to the end of the global list.
1203 * Drivers will by default be put on the list in compiled-in order.
1205 if (!epdrv->list.next) {
1206 INIT_LIST_HEAD(&epdrv->list);
1207 list_add_tail(&epdrv->list, &early_platform_driver_list);
1210 /* If the user has specified device then make sure the driver
1211 * gets prioritized. The driver of the last device specified on
1212 * command line will be put first on the list.
1214 n = strlen(epdrv->pdrv->driver.name);
1215 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1216 list_move(&epdrv->list, &early_platform_driver_list);
1218 /* Allow passing parameters after device name */
1219 if (buf[n] == '\0' || buf[n] == ',')
1220 epdrv->requested_id = -1;
1221 else {
1222 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1223 &tmp, 10);
1225 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1226 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1227 n = 0;
1228 } else
1229 n += strcspn(&buf[n + 1], ",") + 1;
1232 if (buf[n] == ',')
1233 n++;
1235 if (epdrv->bufsize) {
1236 memcpy(epdrv->buffer, &buf[n],
1237 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1238 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1242 return 0;
1246 * early_platform_add_devices - adds a number of early platform devices
1247 * @devs: array of early platform devices to add
1248 * @num: number of early platform devices in array
1250 * Used by early architecture code to register early platform devices and
1251 * their platform data.
1253 void __init early_platform_add_devices(struct platform_device **devs, int num)
1255 struct device *dev;
1256 int i;
1258 /* simply add the devices to list */
1259 for (i = 0; i < num; i++) {
1260 dev = &devs[i]->dev;
1262 if (!dev->devres_head.next) {
1263 pm_runtime_early_init(dev);
1264 INIT_LIST_HEAD(&dev->devres_head);
1265 list_add_tail(&dev->devres_head,
1266 &early_platform_device_list);
1272 * early_platform_driver_register_all - register early platform drivers
1273 * @class_str: string to identify early platform driver class
1275 * Used by architecture code to register all early platform drivers
1276 * for a certain class. If omitted then only early platform drivers
1277 * with matching kernel command line class parameters will be registered.
1279 void __init early_platform_driver_register_all(char *class_str)
1281 /* The "class_str" parameter may or may not be present on the kernel
1282 * command line. If it is present then there may be more than one
1283 * matching parameter.
1285 * Since we register our early platform drivers using early_param()
1286 * we need to make sure that they also get registered in the case
1287 * when the parameter is missing from the kernel command line.
1289 * We use parse_early_options() to make sure the early_param() gets
1290 * called at least once. The early_param() may be called more than
1291 * once since the name of the preferred device may be specified on
1292 * the kernel command line. early_platform_driver_register() handles
1293 * this case for us.
1295 parse_early_options(class_str);
1299 * early_platform_match - find early platform device matching driver
1300 * @epdrv: early platform driver structure
1301 * @id: id to match against
1303 static struct platform_device * __init
1304 early_platform_match(struct early_platform_driver *epdrv, int id)
1306 struct platform_device *pd;
1308 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1309 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1310 if (pd->id == id)
1311 return pd;
1313 return NULL;
1317 * early_platform_left - check if early platform driver has matching devices
1318 * @epdrv: early platform driver structure
1319 * @id: return true if id or above exists
1321 static int __init early_platform_left(struct early_platform_driver *epdrv,
1322 int id)
1324 struct platform_device *pd;
1326 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1327 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1328 if (pd->id >= id)
1329 return 1;
1331 return 0;
1335 * early_platform_driver_probe_id - probe drivers matching class_str and id
1336 * @class_str: string to identify early platform driver class
1337 * @id: id to match against
1338 * @nr_probe: number of platform devices to successfully probe before exiting
1340 static int __init early_platform_driver_probe_id(char *class_str,
1341 int id,
1342 int nr_probe)
1344 struct early_platform_driver *epdrv;
1345 struct platform_device *match;
1346 int match_id;
1347 int n = 0;
1348 int left = 0;
1350 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1351 /* only use drivers matching our class_str */
1352 if (strcmp(class_str, epdrv->class_str))
1353 continue;
1355 if (id == -2) {
1356 match_id = epdrv->requested_id;
1357 left = 1;
1359 } else {
1360 match_id = id;
1361 left += early_platform_left(epdrv, id);
1363 /* skip requested id */
1364 switch (epdrv->requested_id) {
1365 case EARLY_PLATFORM_ID_ERROR:
1366 case EARLY_PLATFORM_ID_UNSET:
1367 break;
1368 default:
1369 if (epdrv->requested_id == id)
1370 match_id = EARLY_PLATFORM_ID_UNSET;
1374 switch (match_id) {
1375 case EARLY_PLATFORM_ID_ERROR:
1376 pr_warn("%s: unable to parse %s parameter\n",
1377 class_str, epdrv->pdrv->driver.name);
1378 /* fall-through */
1379 case EARLY_PLATFORM_ID_UNSET:
1380 match = NULL;
1381 break;
1382 default:
1383 match = early_platform_match(epdrv, match_id);
1386 if (match) {
1388 * Set up a sensible init_name to enable
1389 * dev_name() and others to be used before the
1390 * rest of the driver core is initialized.
1392 if (!match->dev.init_name && slab_is_available()) {
1393 if (match->id != -1)
1394 match->dev.init_name =
1395 kasprintf(GFP_KERNEL, "%s.%d",
1396 match->name,
1397 match->id);
1398 else
1399 match->dev.init_name =
1400 kasprintf(GFP_KERNEL, "%s",
1401 match->name);
1403 if (!match->dev.init_name)
1404 return -ENOMEM;
1407 if (epdrv->pdrv->probe(match))
1408 pr_warn("%s: unable to probe %s early.\n",
1409 class_str, match->name);
1410 else
1411 n++;
1414 if (n >= nr_probe)
1415 break;
1418 if (left)
1419 return n;
1420 else
1421 return -ENODEV;
1425 * early_platform_driver_probe - probe a class of registered drivers
1426 * @class_str: string to identify early platform driver class
1427 * @nr_probe: number of platform devices to successfully probe before exiting
1428 * @user_only: only probe user specified early platform devices
1430 * Used by architecture code to probe registered early platform drivers
1431 * within a certain class. For probe to happen a registered early platform
1432 * device matching a registered early platform driver is needed.
1434 int __init early_platform_driver_probe(char *class_str,
1435 int nr_probe,
1436 int user_only)
1438 int k, n, i;
1440 n = 0;
1441 for (i = -2; n < nr_probe; i++) {
1442 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1444 if (k < 0)
1445 break;
1447 n += k;
1449 if (user_only)
1450 break;
1453 return n;
1457 * early_platform_cleanup - clean up early platform code
1459 void __init early_platform_cleanup(void)
1461 struct platform_device *pd, *pd2;
1463 /* clean up the devres list used to chain devices */
1464 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1465 dev.devres_head) {
1466 list_del(&pd->dev.devres_head);
1467 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));