Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / drivers / base / platform.c
blobf1bf7b38d91ca7ac69a5477ed08103f59e151bbe
1 // SPDX-License-Identifier: GPL-2.0
2 /*
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
9 * information.
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/bootmem.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>
30 #include "base.h"
31 #include "power/power.h"
33 /* For automatically allocated device IDs */
34 static DEFINE_IDA(platform_devid_ida);
36 struct device platform_bus = {
37 .init_name = "platform",
39 EXPORT_SYMBOL_GPL(platform_bus);
41 /**
42 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
43 * @pdev: platform device
45 * This is called before platform_device_add() such that any pdev_archdata may
46 * be setup before the platform_notifier is called. So if a user needs to
47 * manipulate any relevant information in the pdev_archdata they can do:
49 * platform_device_alloc()
50 * ... manipulate ...
51 * platform_device_add()
53 * And if they don't care they can just call platform_device_register() and
54 * everything will just work out.
56 void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
60 /**
61 * platform_get_resource - get a resource for a device
62 * @dev: platform device
63 * @type: resource type
64 * @num: resource index
66 struct resource *platform_get_resource(struct platform_device *dev,
67 unsigned int type, unsigned int num)
69 int i;
71 for (i = 0; i < dev->num_resources; i++) {
72 struct resource *r = &dev->resource[i];
74 if (type == resource_type(r) && num-- == 0)
75 return r;
77 return NULL;
79 EXPORT_SYMBOL_GPL(platform_get_resource);
81 /**
82 * platform_get_irq - get an IRQ for a device
83 * @dev: platform device
84 * @num: IRQ number index
86 int platform_get_irq(struct platform_device *dev, unsigned int num)
88 #ifdef CONFIG_SPARC
89 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
90 if (!dev || num >= dev->archdata.num_irqs)
91 return -ENXIO;
92 return dev->archdata.irqs[num];
93 #else
94 struct resource *r;
95 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
96 int ret;
98 ret = of_irq_get(dev->dev.of_node, num);
99 if (ret > 0 || ret == -EPROBE_DEFER)
100 return ret;
103 r = platform_get_resource(dev, IORESOURCE_IRQ, num);
104 if (has_acpi_companion(&dev->dev)) {
105 if (r && r->flags & IORESOURCE_DISABLED) {
106 int ret;
108 ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
109 if (ret)
110 return ret;
115 * The resources may pass trigger flags to the irqs that need
116 * to be set up. It so happens that the trigger flags for
117 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
118 * settings.
120 if (r && r->flags & IORESOURCE_BITS) {
121 struct irq_data *irqd;
123 irqd = irq_get_irq_data(r->start);
124 if (!irqd)
125 return -ENXIO;
126 irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
129 return r ? r->start : -ENXIO;
130 #endif
132 EXPORT_SYMBOL_GPL(platform_get_irq);
135 * platform_irq_count - Count the number of IRQs a platform device uses
136 * @dev: platform device
138 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
140 int platform_irq_count(struct platform_device *dev)
142 int ret, nr = 0;
144 while ((ret = platform_get_irq(dev, nr)) >= 0)
145 nr++;
147 if (ret == -EPROBE_DEFER)
148 return ret;
150 return nr;
152 EXPORT_SYMBOL_GPL(platform_irq_count);
155 * platform_get_resource_byname - get a resource for a device by name
156 * @dev: platform device
157 * @type: resource type
158 * @name: resource name
160 struct resource *platform_get_resource_byname(struct platform_device *dev,
161 unsigned int type,
162 const char *name)
164 int i;
166 for (i = 0; i < dev->num_resources; i++) {
167 struct resource *r = &dev->resource[i];
169 if (unlikely(!r->name))
170 continue;
172 if (type == resource_type(r) && !strcmp(r->name, name))
173 return r;
175 return NULL;
177 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
180 * platform_get_irq_byname - get an IRQ for a device by name
181 * @dev: platform device
182 * @name: IRQ name
184 int platform_get_irq_byname(struct platform_device *dev, const char *name)
186 struct resource *r;
188 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
189 int ret;
191 ret = of_irq_get_byname(dev->dev.of_node, name);
192 if (ret > 0 || ret == -EPROBE_DEFER)
193 return ret;
196 r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
197 return r ? r->start : -ENXIO;
199 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
202 * platform_add_devices - add a numbers of platform devices
203 * @devs: array of platform devices to add
204 * @num: number of platform devices in array
206 int platform_add_devices(struct platform_device **devs, int num)
208 int i, ret = 0;
210 for (i = 0; i < num; i++) {
211 ret = platform_device_register(devs[i]);
212 if (ret) {
213 while (--i >= 0)
214 platform_device_unregister(devs[i]);
215 break;
219 return ret;
221 EXPORT_SYMBOL_GPL(platform_add_devices);
223 struct platform_object {
224 struct platform_device pdev;
225 char name[];
229 * platform_device_put - destroy a platform device
230 * @pdev: platform device to free
232 * Free all memory associated with a platform device. This function must
233 * _only_ be externally called in error cases. All other usage is a bug.
235 void platform_device_put(struct platform_device *pdev)
237 if (pdev)
238 put_device(&pdev->dev);
240 EXPORT_SYMBOL_GPL(platform_device_put);
242 static void platform_device_release(struct device *dev)
244 struct platform_object *pa = container_of(dev, struct platform_object,
245 pdev.dev);
247 of_device_node_put(&pa->pdev.dev);
248 kfree(pa->pdev.dev.platform_data);
249 kfree(pa->pdev.mfd_cell);
250 kfree(pa->pdev.resource);
251 kfree(pa->pdev.driver_override);
252 kfree(pa);
256 * platform_device_alloc - create a platform device
257 * @name: base name of the device we're adding
258 * @id: instance id
260 * Create a platform device object which can have other objects attached
261 * to it, and which will have attached objects freed when it is released.
263 struct platform_device *platform_device_alloc(const char *name, int id)
265 struct platform_object *pa;
267 pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
268 if (pa) {
269 strcpy(pa->name, name);
270 pa->pdev.name = pa->name;
271 pa->pdev.id = id;
272 device_initialize(&pa->pdev.dev);
273 pa->pdev.dev.release = platform_device_release;
274 arch_setup_pdev_archdata(&pa->pdev);
277 return pa ? &pa->pdev : NULL;
279 EXPORT_SYMBOL_GPL(platform_device_alloc);
282 * platform_device_add_resources - add resources to a platform device
283 * @pdev: platform device allocated by platform_device_alloc to add resources to
284 * @res: set of resources that needs to be allocated for the device
285 * @num: number of resources
287 * Add a copy of the resources to the platform device. The memory
288 * associated with the resources will be freed when the platform device is
289 * released.
291 int platform_device_add_resources(struct platform_device *pdev,
292 const struct resource *res, unsigned int num)
294 struct resource *r = NULL;
296 if (res) {
297 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
298 if (!r)
299 return -ENOMEM;
302 kfree(pdev->resource);
303 pdev->resource = r;
304 pdev->num_resources = num;
305 return 0;
307 EXPORT_SYMBOL_GPL(platform_device_add_resources);
310 * platform_device_add_data - add platform-specific data to a platform device
311 * @pdev: platform device allocated by platform_device_alloc to add resources to
312 * @data: platform specific data for this platform device
313 * @size: size of platform specific data
315 * Add a copy of platform specific data to the platform device's
316 * platform_data pointer. The memory associated with the platform data
317 * will be freed when the platform device is released.
319 int platform_device_add_data(struct platform_device *pdev, const void *data,
320 size_t size)
322 void *d = NULL;
324 if (data) {
325 d = kmemdup(data, size, GFP_KERNEL);
326 if (!d)
327 return -ENOMEM;
330 kfree(pdev->dev.platform_data);
331 pdev->dev.platform_data = d;
332 return 0;
334 EXPORT_SYMBOL_GPL(platform_device_add_data);
337 * platform_device_add_properties - add built-in properties to a platform device
338 * @pdev: platform device to add properties to
339 * @properties: null terminated array of properties to add
341 * The function will take deep copy of @properties and attach the copy to the
342 * platform device. The memory associated with properties will be freed when the
343 * platform device is released.
345 int platform_device_add_properties(struct platform_device *pdev,
346 const struct property_entry *properties)
348 return device_add_properties(&pdev->dev, properties);
350 EXPORT_SYMBOL_GPL(platform_device_add_properties);
353 * platform_device_add - add a platform device to device hierarchy
354 * @pdev: platform device we're adding
356 * This is part 2 of platform_device_register(), though may be called
357 * separately _iff_ pdev was allocated by platform_device_alloc().
359 int platform_device_add(struct platform_device *pdev)
361 int i, ret;
363 if (!pdev)
364 return -EINVAL;
366 if (!pdev->dev.parent)
367 pdev->dev.parent = &platform_bus;
369 pdev->dev.bus = &platform_bus_type;
371 switch (pdev->id) {
372 default:
373 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
374 break;
375 case PLATFORM_DEVID_NONE:
376 dev_set_name(&pdev->dev, "%s", pdev->name);
377 break;
378 case PLATFORM_DEVID_AUTO:
380 * Automatically allocated device ID. We mark it as such so
381 * that we remember it must be freed, and we append a suffix
382 * to avoid namespace collision with explicit IDs.
384 ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
385 if (ret < 0)
386 goto err_out;
387 pdev->id = ret;
388 pdev->id_auto = true;
389 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
390 break;
393 for (i = 0; i < pdev->num_resources; i++) {
394 struct resource *p, *r = &pdev->resource[i];
396 if (r->name == NULL)
397 r->name = dev_name(&pdev->dev);
399 p = r->parent;
400 if (!p) {
401 if (resource_type(r) == IORESOURCE_MEM)
402 p = &iomem_resource;
403 else if (resource_type(r) == IORESOURCE_IO)
404 p = &ioport_resource;
407 if (p && insert_resource(p, r)) {
408 dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
409 ret = -EBUSY;
410 goto failed;
414 pr_debug("Registering platform device '%s'. Parent at %s\n",
415 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
417 ret = device_add(&pdev->dev);
418 if (ret == 0)
419 return ret;
421 failed:
422 if (pdev->id_auto) {
423 ida_simple_remove(&platform_devid_ida, pdev->id);
424 pdev->id = PLATFORM_DEVID_AUTO;
427 while (--i >= 0) {
428 struct resource *r = &pdev->resource[i];
429 if (r->parent)
430 release_resource(r);
433 err_out:
434 return ret;
436 EXPORT_SYMBOL_GPL(platform_device_add);
439 * platform_device_del - remove a platform-level device
440 * @pdev: platform device we're removing
442 * Note that this function will also release all memory- and port-based
443 * resources owned by the device (@dev->resource). This function must
444 * _only_ be externally called in error cases. All other usage is a bug.
446 void platform_device_del(struct platform_device *pdev)
448 int i;
450 if (pdev) {
451 device_remove_properties(&pdev->dev);
452 device_del(&pdev->dev);
454 if (pdev->id_auto) {
455 ida_simple_remove(&platform_devid_ida, pdev->id);
456 pdev->id = PLATFORM_DEVID_AUTO;
459 for (i = 0; i < pdev->num_resources; i++) {
460 struct resource *r = &pdev->resource[i];
461 if (r->parent)
462 release_resource(r);
466 EXPORT_SYMBOL_GPL(platform_device_del);
469 * platform_device_register - add a platform-level device
470 * @pdev: platform device we're adding
472 int platform_device_register(struct platform_device *pdev)
474 device_initialize(&pdev->dev);
475 arch_setup_pdev_archdata(pdev);
476 return platform_device_add(pdev);
478 EXPORT_SYMBOL_GPL(platform_device_register);
481 * platform_device_unregister - unregister a platform-level device
482 * @pdev: platform device we're unregistering
484 * Unregistration is done in 2 steps. First we release all resources
485 * and remove it from the subsystem, then we drop reference count by
486 * calling platform_device_put().
488 void platform_device_unregister(struct platform_device *pdev)
490 platform_device_del(pdev);
491 platform_device_put(pdev);
493 EXPORT_SYMBOL_GPL(platform_device_unregister);
496 * platform_device_register_full - add a platform-level device with
497 * resources and platform-specific data
499 * @pdevinfo: data used to create device
501 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
503 struct platform_device *platform_device_register_full(
504 const struct platform_device_info *pdevinfo)
506 int ret = -ENOMEM;
507 struct platform_device *pdev;
509 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
510 if (!pdev)
511 goto err_alloc;
513 pdev->dev.parent = pdevinfo->parent;
514 pdev->dev.fwnode = pdevinfo->fwnode;
516 if (pdevinfo->dma_mask) {
518 * This memory isn't freed when the device is put,
519 * I don't have a nice idea for that though. Conceptually
520 * dma_mask in struct device should not be a pointer.
521 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
523 pdev->dev.dma_mask =
524 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
525 if (!pdev->dev.dma_mask)
526 goto err;
528 *pdev->dev.dma_mask = pdevinfo->dma_mask;
529 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
532 ret = platform_device_add_resources(pdev,
533 pdevinfo->res, pdevinfo->num_res);
534 if (ret)
535 goto err;
537 ret = platform_device_add_data(pdev,
538 pdevinfo->data, pdevinfo->size_data);
539 if (ret)
540 goto err;
542 if (pdevinfo->properties) {
543 ret = platform_device_add_properties(pdev,
544 pdevinfo->properties);
545 if (ret)
546 goto err;
549 ret = platform_device_add(pdev);
550 if (ret) {
551 err:
552 ACPI_COMPANION_SET(&pdev->dev, NULL);
553 kfree(pdev->dev.dma_mask);
555 err_alloc:
556 platform_device_put(pdev);
557 return ERR_PTR(ret);
560 return pdev;
562 EXPORT_SYMBOL_GPL(platform_device_register_full);
564 static int platform_drv_probe(struct device *_dev)
566 struct platform_driver *drv = to_platform_driver(_dev->driver);
567 struct platform_device *dev = to_platform_device(_dev);
568 int ret;
570 ret = of_clk_set_defaults(_dev->of_node, false);
571 if (ret < 0)
572 return ret;
574 ret = dev_pm_domain_attach(_dev, true);
575 if (ret != -EPROBE_DEFER) {
576 if (drv->probe) {
577 ret = drv->probe(dev);
578 if (ret)
579 dev_pm_domain_detach(_dev, true);
580 } else {
581 /* don't fail if just dev_pm_domain_attach failed */
582 ret = 0;
586 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
587 dev_warn(_dev, "probe deferral not supported\n");
588 ret = -ENXIO;
591 return ret;
594 static int platform_drv_probe_fail(struct device *_dev)
596 return -ENXIO;
599 static int platform_drv_remove(struct device *_dev)
601 struct platform_driver *drv = to_platform_driver(_dev->driver);
602 struct platform_device *dev = to_platform_device(_dev);
603 int ret = 0;
605 if (drv->remove)
606 ret = drv->remove(dev);
607 dev_pm_domain_detach(_dev, true);
609 return ret;
612 static void platform_drv_shutdown(struct device *_dev)
614 struct platform_driver *drv = to_platform_driver(_dev->driver);
615 struct platform_device *dev = to_platform_device(_dev);
617 if (drv->shutdown)
618 drv->shutdown(dev);
622 * __platform_driver_register - register a driver for platform-level devices
623 * @drv: platform driver structure
624 * @owner: owning module/driver
626 int __platform_driver_register(struct platform_driver *drv,
627 struct module *owner)
629 drv->driver.owner = owner;
630 drv->driver.bus = &platform_bus_type;
631 drv->driver.probe = platform_drv_probe;
632 drv->driver.remove = platform_drv_remove;
633 drv->driver.shutdown = platform_drv_shutdown;
635 return driver_register(&drv->driver);
637 EXPORT_SYMBOL_GPL(__platform_driver_register);
640 * platform_driver_unregister - unregister a driver for platform-level devices
641 * @drv: platform driver structure
643 void platform_driver_unregister(struct platform_driver *drv)
645 driver_unregister(&drv->driver);
647 EXPORT_SYMBOL_GPL(platform_driver_unregister);
650 * __platform_driver_probe - register driver for non-hotpluggable device
651 * @drv: platform driver structure
652 * @probe: the driver probe routine, probably from an __init section
653 * @module: module which will be the owner of the driver
655 * Use this instead of platform_driver_register() when you know the device
656 * is not hotpluggable and has already been registered, and you want to
657 * remove its run-once probe() infrastructure from memory after the driver
658 * has bound to the device.
660 * One typical use for this would be with drivers for controllers integrated
661 * into system-on-chip processors, where the controller devices have been
662 * configured as part of board setup.
664 * Note that this is incompatible with deferred probing.
666 * Returns zero if the driver registered and bound to a device, else returns
667 * a negative error code and with the driver not registered.
669 int __init_or_module __platform_driver_probe(struct platform_driver *drv,
670 int (*probe)(struct platform_device *), struct module *module)
672 int retval, code;
674 if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
675 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
676 drv->driver.name, __func__);
677 return -EINVAL;
681 * We have to run our probes synchronously because we check if
682 * we find any devices to bind to and exit with error if there
683 * are any.
685 drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
688 * Prevent driver from requesting probe deferral to avoid further
689 * futile probe attempts.
691 drv->prevent_deferred_probe = true;
693 /* make sure driver won't have bind/unbind attributes */
694 drv->driver.suppress_bind_attrs = true;
696 /* temporary section violation during probe() */
697 drv->probe = probe;
698 retval = code = __platform_driver_register(drv, module);
701 * Fixup that section violation, being paranoid about code scanning
702 * the list of drivers in order to probe new devices. Check to see
703 * if the probe was successful, and make sure any forced probes of
704 * new devices fail.
706 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
707 drv->probe = NULL;
708 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
709 retval = -ENODEV;
710 drv->driver.probe = platform_drv_probe_fail;
711 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
713 if (code != retval)
714 platform_driver_unregister(drv);
715 return retval;
717 EXPORT_SYMBOL_GPL(__platform_driver_probe);
720 * __platform_create_bundle - register driver and create corresponding device
721 * @driver: platform driver structure
722 * @probe: the driver probe routine, probably from an __init section
723 * @res: set of resources that needs to be allocated for the device
724 * @n_res: number of resources
725 * @data: platform specific data for this platform device
726 * @size: size of platform specific data
727 * @module: module which will be the owner of the driver
729 * Use this in legacy-style modules that probe hardware directly and
730 * register a single platform device and corresponding platform driver.
732 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
734 struct platform_device * __init_or_module __platform_create_bundle(
735 struct platform_driver *driver,
736 int (*probe)(struct platform_device *),
737 struct resource *res, unsigned int n_res,
738 const void *data, size_t size, struct module *module)
740 struct platform_device *pdev;
741 int error;
743 pdev = platform_device_alloc(driver->driver.name, -1);
744 if (!pdev) {
745 error = -ENOMEM;
746 goto err_out;
749 error = platform_device_add_resources(pdev, res, n_res);
750 if (error)
751 goto err_pdev_put;
753 error = platform_device_add_data(pdev, data, size);
754 if (error)
755 goto err_pdev_put;
757 error = platform_device_add(pdev);
758 if (error)
759 goto err_pdev_put;
761 error = __platform_driver_probe(driver, probe, module);
762 if (error)
763 goto err_pdev_del;
765 return pdev;
767 err_pdev_del:
768 platform_device_del(pdev);
769 err_pdev_put:
770 platform_device_put(pdev);
771 err_out:
772 return ERR_PTR(error);
774 EXPORT_SYMBOL_GPL(__platform_create_bundle);
777 * __platform_register_drivers - register an array of platform drivers
778 * @drivers: an array of drivers to register
779 * @count: the number of drivers to register
780 * @owner: module owning the drivers
782 * Registers platform drivers specified by an array. On failure to register a
783 * driver, all previously registered drivers will be unregistered. Callers of
784 * this API should use platform_unregister_drivers() to unregister drivers in
785 * the reverse order.
787 * Returns: 0 on success or a negative error code on failure.
789 int __platform_register_drivers(struct platform_driver * const *drivers,
790 unsigned int count, struct module *owner)
792 unsigned int i;
793 int err;
795 for (i = 0; i < count; i++) {
796 pr_debug("registering platform driver %ps\n", drivers[i]);
798 err = __platform_driver_register(drivers[i], owner);
799 if (err < 0) {
800 pr_err("failed to register platform driver %ps: %d\n",
801 drivers[i], err);
802 goto error;
806 return 0;
808 error:
809 while (i--) {
810 pr_debug("unregistering platform driver %ps\n", drivers[i]);
811 platform_driver_unregister(drivers[i]);
814 return err;
816 EXPORT_SYMBOL_GPL(__platform_register_drivers);
819 * platform_unregister_drivers - unregister an array of platform drivers
820 * @drivers: an array of drivers to unregister
821 * @count: the number of drivers to unregister
823 * Unegisters platform drivers specified by an array. This is typically used
824 * to complement an earlier call to platform_register_drivers(). Drivers are
825 * unregistered in the reverse order in which they were registered.
827 void platform_unregister_drivers(struct platform_driver * const *drivers,
828 unsigned int count)
830 while (count--) {
831 pr_debug("unregistering platform driver %ps\n", drivers[count]);
832 platform_driver_unregister(drivers[count]);
835 EXPORT_SYMBOL_GPL(platform_unregister_drivers);
837 /* modalias support enables more hands-off userspace setup:
838 * (a) environment variable lets new-style hotplug events work once system is
839 * fully running: "modprobe $MODALIAS"
840 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
841 * mishandled before system is fully running: "modprobe $(cat modalias)"
843 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
844 char *buf)
846 struct platform_device *pdev = to_platform_device(dev);
847 int len;
849 len = of_device_modalias(dev, buf, PAGE_SIZE);
850 if (len != -ENODEV)
851 return len;
853 len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
854 if (len != -ENODEV)
855 return len;
857 len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
859 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
861 static DEVICE_ATTR_RO(modalias);
863 static ssize_t driver_override_store(struct device *dev,
864 struct device_attribute *attr,
865 const char *buf, size_t count)
867 struct platform_device *pdev = to_platform_device(dev);
868 char *driver_override, *old, *cp;
870 /* We need to keep extra room for a newline */
871 if (count >= (PAGE_SIZE - 1))
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,
1145 .force_dma = true,
1147 EXPORT_SYMBOL_GPL(platform_bus_type);
1149 int __init platform_bus_init(void)
1151 int error;
1153 early_platform_cleanup();
1155 error = device_register(&platform_bus);
1156 if (error)
1157 return error;
1158 error = bus_register(&platform_bus_type);
1159 if (error)
1160 device_unregister(&platform_bus);
1161 of_platform_register_reconfig_notifier();
1162 return error;
1165 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1166 u64 dma_get_required_mask(struct device *dev)
1168 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
1169 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1170 u64 mask;
1172 if (!high_totalram) {
1173 /* convert to mask just covering totalram */
1174 low_totalram = (1 << (fls(low_totalram) - 1));
1175 low_totalram += low_totalram - 1;
1176 mask = low_totalram;
1177 } else {
1178 high_totalram = (1 << (fls(high_totalram) - 1));
1179 high_totalram += high_totalram - 1;
1180 mask = (((u64)high_totalram) << 32) + 0xffffffff;
1182 return mask;
1184 EXPORT_SYMBOL_GPL(dma_get_required_mask);
1185 #endif
1187 static __initdata LIST_HEAD(early_platform_driver_list);
1188 static __initdata LIST_HEAD(early_platform_device_list);
1191 * early_platform_driver_register - register early platform driver
1192 * @epdrv: early_platform driver structure
1193 * @buf: string passed from early_param()
1195 * Helper function for early_platform_init() / early_platform_init_buffer()
1197 int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1198 char *buf)
1200 char *tmp;
1201 int n;
1203 /* Simply add the driver to the end of the global list.
1204 * Drivers will by default be put on the list in compiled-in order.
1206 if (!epdrv->list.next) {
1207 INIT_LIST_HEAD(&epdrv->list);
1208 list_add_tail(&epdrv->list, &early_platform_driver_list);
1211 /* If the user has specified device then make sure the driver
1212 * gets prioritized. The driver of the last device specified on
1213 * command line will be put first on the list.
1215 n = strlen(epdrv->pdrv->driver.name);
1216 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1217 list_move(&epdrv->list, &early_platform_driver_list);
1219 /* Allow passing parameters after device name */
1220 if (buf[n] == '\0' || buf[n] == ',')
1221 epdrv->requested_id = -1;
1222 else {
1223 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1224 &tmp, 10);
1226 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1227 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1228 n = 0;
1229 } else
1230 n += strcspn(&buf[n + 1], ",") + 1;
1233 if (buf[n] == ',')
1234 n++;
1236 if (epdrv->bufsize) {
1237 memcpy(epdrv->buffer, &buf[n],
1238 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1239 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1243 return 0;
1247 * early_platform_add_devices - adds a number of early platform devices
1248 * @devs: array of early platform devices to add
1249 * @num: number of early platform devices in array
1251 * Used by early architecture code to register early platform devices and
1252 * their platform data.
1254 void __init early_platform_add_devices(struct platform_device **devs, int num)
1256 struct device *dev;
1257 int i;
1259 /* simply add the devices to list */
1260 for (i = 0; i < num; i++) {
1261 dev = &devs[i]->dev;
1263 if (!dev->devres_head.next) {
1264 pm_runtime_early_init(dev);
1265 INIT_LIST_HEAD(&dev->devres_head);
1266 list_add_tail(&dev->devres_head,
1267 &early_platform_device_list);
1273 * early_platform_driver_register_all - register early platform drivers
1274 * @class_str: string to identify early platform driver class
1276 * Used by architecture code to register all early platform drivers
1277 * for a certain class. If omitted then only early platform drivers
1278 * with matching kernel command line class parameters will be registered.
1280 void __init early_platform_driver_register_all(char *class_str)
1282 /* The "class_str" parameter may or may not be present on the kernel
1283 * command line. If it is present then there may be more than one
1284 * matching parameter.
1286 * Since we register our early platform drivers using early_param()
1287 * we need to make sure that they also get registered in the case
1288 * when the parameter is missing from the kernel command line.
1290 * We use parse_early_options() to make sure the early_param() gets
1291 * called at least once. The early_param() may be called more than
1292 * once since the name of the preferred device may be specified on
1293 * the kernel command line. early_platform_driver_register() handles
1294 * this case for us.
1296 parse_early_options(class_str);
1300 * early_platform_match - find early platform device matching driver
1301 * @epdrv: early platform driver structure
1302 * @id: id to match against
1304 static struct platform_device * __init
1305 early_platform_match(struct early_platform_driver *epdrv, int id)
1307 struct platform_device *pd;
1309 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1310 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1311 if (pd->id == id)
1312 return pd;
1314 return NULL;
1318 * early_platform_left - check if early platform driver has matching devices
1319 * @epdrv: early platform driver structure
1320 * @id: return true if id or above exists
1322 static int __init early_platform_left(struct early_platform_driver *epdrv,
1323 int id)
1325 struct platform_device *pd;
1327 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1328 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1329 if (pd->id >= id)
1330 return 1;
1332 return 0;
1336 * early_platform_driver_probe_id - probe drivers matching class_str and id
1337 * @class_str: string to identify early platform driver class
1338 * @id: id to match against
1339 * @nr_probe: number of platform devices to successfully probe before exiting
1341 static int __init early_platform_driver_probe_id(char *class_str,
1342 int id,
1343 int nr_probe)
1345 struct early_platform_driver *epdrv;
1346 struct platform_device *match;
1347 int match_id;
1348 int n = 0;
1349 int left = 0;
1351 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1352 /* only use drivers matching our class_str */
1353 if (strcmp(class_str, epdrv->class_str))
1354 continue;
1356 if (id == -2) {
1357 match_id = epdrv->requested_id;
1358 left = 1;
1360 } else {
1361 match_id = id;
1362 left += early_platform_left(epdrv, id);
1364 /* skip requested id */
1365 switch (epdrv->requested_id) {
1366 case EARLY_PLATFORM_ID_ERROR:
1367 case EARLY_PLATFORM_ID_UNSET:
1368 break;
1369 default:
1370 if (epdrv->requested_id == id)
1371 match_id = EARLY_PLATFORM_ID_UNSET;
1375 switch (match_id) {
1376 case EARLY_PLATFORM_ID_ERROR:
1377 pr_warn("%s: unable to parse %s parameter\n",
1378 class_str, epdrv->pdrv->driver.name);
1379 /* fall-through */
1380 case EARLY_PLATFORM_ID_UNSET:
1381 match = NULL;
1382 break;
1383 default:
1384 match = early_platform_match(epdrv, match_id);
1387 if (match) {
1389 * Set up a sensible init_name to enable
1390 * dev_name() and others to be used before the
1391 * rest of the driver core is initialized.
1393 if (!match->dev.init_name && slab_is_available()) {
1394 if (match->id != -1)
1395 match->dev.init_name =
1396 kasprintf(GFP_KERNEL, "%s.%d",
1397 match->name,
1398 match->id);
1399 else
1400 match->dev.init_name =
1401 kasprintf(GFP_KERNEL, "%s",
1402 match->name);
1404 if (!match->dev.init_name)
1405 return -ENOMEM;
1408 if (epdrv->pdrv->probe(match))
1409 pr_warn("%s: unable to probe %s early.\n",
1410 class_str, match->name);
1411 else
1412 n++;
1415 if (n >= nr_probe)
1416 break;
1419 if (left)
1420 return n;
1421 else
1422 return -ENODEV;
1426 * early_platform_driver_probe - probe a class of registered drivers
1427 * @class_str: string to identify early platform driver class
1428 * @nr_probe: number of platform devices to successfully probe before exiting
1429 * @user_only: only probe user specified early platform devices
1431 * Used by architecture code to probe registered early platform drivers
1432 * within a certain class. For probe to happen a registered early platform
1433 * device matching a registered early platform driver is needed.
1435 int __init early_platform_driver_probe(char *class_str,
1436 int nr_probe,
1437 int user_only)
1439 int k, n, i;
1441 n = 0;
1442 for (i = -2; n < nr_probe; i++) {
1443 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1445 if (k < 0)
1446 break;
1448 n += k;
1450 if (user_only)
1451 break;
1454 return n;
1458 * early_platform_cleanup - clean up early platform code
1460 void __init early_platform_cleanup(void)
1462 struct platform_device *pd, *pd2;
1464 /* clean up the devres list used to chain devices */
1465 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1466 dev.devres_head) {
1467 list_del(&pd->dev.devres_head);
1468 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));