1/*
2 * platform.c - platform 'pseudo' bus for legacy devices
3 *
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
6 *
7 * This file is released under the GPLv2
8 *
9 * Please see Documentation/driver-model/platform.txt for more
10 * information.
11 */
12
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
30#include "base.h"
31#include "power/power.h"
32
33/* For automatically allocated device IDs */
34static DEFINE_IDA(platform_devid_ida);
35
36struct device platform_bus = {
37	.init_name	= "platform",
38};
39EXPORT_SYMBOL_GPL(platform_bus);
40
41/**
42 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
43 * @pdev: platform device
44 *
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:
48 *
49 *	platform_device_alloc()
50 *	... manipulate ...
51 *	platform_device_add()
52 *
53 * And if they don't care they can just call platform_device_register() and
54 * everything will just work out.
55 */
56void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
57{
58}
59
60/**
61 * platform_get_resource - get a resource for a device
62 * @dev: platform device
63 * @type: resource type
64 * @num: resource index
65 */
66struct resource *platform_get_resource(struct platform_device *dev,
67				       unsigned int type, unsigned int num)
68{
69	int i;
70
71	for (i = 0; i < dev->num_resources; i++) {
72		struct resource *r = &dev->resource[i];
73
74		if (type == resource_type(r) && num-- == 0)
75			return r;
76	}
77	return NULL;
78}
79EXPORT_SYMBOL_GPL(platform_get_resource);
80
81/**
82 * platform_get_irq - get an IRQ for a device
83 * @dev: platform device
84 * @num: IRQ number index
85 */
86int platform_get_irq(struct platform_device *dev, unsigned int num)
87{
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;
97
98		ret = of_irq_get(dev->dev.of_node, num);
99		if (ret >= 0 || ret == -EPROBE_DEFER)
100			return ret;
101	}
102
103	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
104	/*
105	 * The resources may pass trigger flags to the irqs that need
106	 * to be set up. It so happens that the trigger flags for
107	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
108	 * settings.
109	 */
110	if (r && r->flags & IORESOURCE_BITS)
111		irqd_set_trigger_type(irq_get_irq_data(r->start),
112				      r->flags & IORESOURCE_BITS);
113
114	return r ? r->start : -ENXIO;
115#endif
116}
117EXPORT_SYMBOL_GPL(platform_get_irq);
118
119/**
120 * platform_get_resource_byname - get a resource for a device by name
121 * @dev: platform device
122 * @type: resource type
123 * @name: resource name
124 */
125struct resource *platform_get_resource_byname(struct platform_device *dev,
126					      unsigned int type,
127					      const char *name)
128{
129	int i;
130
131	for (i = 0; i < dev->num_resources; i++) {
132		struct resource *r = &dev->resource[i];
133
134		if (unlikely(!r->name))
135			continue;
136
137		if (type == resource_type(r) && !strcmp(r->name, name))
138			return r;
139	}
140	return NULL;
141}
142EXPORT_SYMBOL_GPL(platform_get_resource_byname);
143
144/**
145 * platform_get_irq_byname - get an IRQ for a device by name
146 * @dev: platform device
147 * @name: IRQ name
148 */
149int platform_get_irq_byname(struct platform_device *dev, const char *name)
150{
151	struct resource *r;
152
153	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
154		int ret;
155
156		ret = of_irq_get_byname(dev->dev.of_node, name);
157		if (ret >= 0 || ret == -EPROBE_DEFER)
158			return ret;
159	}
160
161	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
162	return r ? r->start : -ENXIO;
163}
164EXPORT_SYMBOL_GPL(platform_get_irq_byname);
165
166/**
167 * platform_add_devices - add a numbers of platform devices
168 * @devs: array of platform devices to add
169 * @num: number of platform devices in array
170 */
171int platform_add_devices(struct platform_device **devs, int num)
172{
173	int i, ret = 0;
174
175	for (i = 0; i < num; i++) {
176		ret = platform_device_register(devs[i]);
177		if (ret) {
178			while (--i >= 0)
179				platform_device_unregister(devs[i]);
180			break;
181		}
182	}
183
184	return ret;
185}
186EXPORT_SYMBOL_GPL(platform_add_devices);
187
188struct platform_object {
189	struct platform_device pdev;
190	char name[];
191};
192
193/**
194 * platform_device_put - destroy a platform device
195 * @pdev: platform device to free
196 *
197 * Free all memory associated with a platform device.  This function must
198 * _only_ be externally called in error cases.  All other usage is a bug.
199 */
200void platform_device_put(struct platform_device *pdev)
201{
202	if (pdev)
203		put_device(&pdev->dev);
204}
205EXPORT_SYMBOL_GPL(platform_device_put);
206
207static void platform_device_release(struct device *dev)
208{
209	struct platform_object *pa = container_of(dev, struct platform_object,
210						  pdev.dev);
211
212	of_device_node_put(&pa->pdev.dev);
213	kfree(pa->pdev.dev.platform_data);
214	kfree(pa->pdev.mfd_cell);
215	kfree(pa->pdev.resource);
216	kfree(pa->pdev.driver_override);
217	kfree(pa);
218}
219
220/**
221 * platform_device_alloc - create a platform device
222 * @name: base name of the device we're adding
223 * @id: instance id
224 *
225 * Create a platform device object which can have other objects attached
226 * to it, and which will have attached objects freed when it is released.
227 */
228struct platform_device *platform_device_alloc(const char *name, int id)
229{
230	struct platform_object *pa;
231
232	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
233	if (pa) {
234		strcpy(pa->name, name);
235		pa->pdev.name = pa->name;
236		pa->pdev.id = id;
237		device_initialize(&pa->pdev.dev);
238		pa->pdev.dev.release = platform_device_release;
239		arch_setup_pdev_archdata(&pa->pdev);
240	}
241
242	return pa ? &pa->pdev : NULL;
243}
244EXPORT_SYMBOL_GPL(platform_device_alloc);
245
246/**
247 * platform_device_add_resources - add resources to a platform device
248 * @pdev: platform device allocated by platform_device_alloc to add resources to
249 * @res: set of resources that needs to be allocated for the device
250 * @num: number of resources
251 *
252 * Add a copy of the resources to the platform device.  The memory
253 * associated with the resources will be freed when the platform device is
254 * released.
255 */
256int platform_device_add_resources(struct platform_device *pdev,
257				  const struct resource *res, unsigned int num)
258{
259	struct resource *r = NULL;
260
261	if (res) {
262		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
263		if (!r)
264			return -ENOMEM;
265	}
266
267	kfree(pdev->resource);
268	pdev->resource = r;
269	pdev->num_resources = num;
270	return 0;
271}
272EXPORT_SYMBOL_GPL(platform_device_add_resources);
273
274/**
275 * platform_device_add_data - add platform-specific data to a platform device
276 * @pdev: platform device allocated by platform_device_alloc to add resources to
277 * @data: platform specific data for this platform device
278 * @size: size of platform specific data
279 *
280 * Add a copy of platform specific data to the platform device's
281 * platform_data pointer.  The memory associated with the platform data
282 * will be freed when the platform device is released.
283 */
284int platform_device_add_data(struct platform_device *pdev, const void *data,
285			     size_t size)
286{
287	void *d = NULL;
288
289	if (data) {
290		d = kmemdup(data, size, GFP_KERNEL);
291		if (!d)
292			return -ENOMEM;
293	}
294
295	kfree(pdev->dev.platform_data);
296	pdev->dev.platform_data = d;
297	return 0;
298}
299EXPORT_SYMBOL_GPL(platform_device_add_data);
300
301/**
302 * platform_device_add - add a platform device to device hierarchy
303 * @pdev: platform device we're adding
304 *
305 * This is part 2 of platform_device_register(), though may be called
306 * separately _iff_ pdev was allocated by platform_device_alloc().
307 */
308int platform_device_add(struct platform_device *pdev)
309{
310	int i, ret;
311
312	if (!pdev)
313		return -EINVAL;
314
315	if (!pdev->dev.parent)
316		pdev->dev.parent = &platform_bus;
317
318	pdev->dev.bus = &platform_bus_type;
319
320	switch (pdev->id) {
321	default:
322		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
323		break;
324	case PLATFORM_DEVID_NONE:
325		dev_set_name(&pdev->dev, "%s", pdev->name);
326		break;
327	case PLATFORM_DEVID_AUTO:
328		/*
329		 * Automatically allocated device ID. We mark it as such so
330		 * that we remember it must be freed, and we append a suffix
331		 * to avoid namespace collision with explicit IDs.
332		 */
333		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
334		if (ret < 0)
335			goto err_out;
336		pdev->id = ret;
337		pdev->id_auto = true;
338		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
339		break;
340	}
341
342	for (i = 0; i < pdev->num_resources; i++) {
343		struct resource *p, *r = &pdev->resource[i];
344
345		if (r->name == NULL)
346			r->name = dev_name(&pdev->dev);
347
348		p = r->parent;
349		if (!p) {
350			if (resource_type(r) == IORESOURCE_MEM)
351				p = &iomem_resource;
352			else if (resource_type(r) == IORESOURCE_IO)
353				p = &ioport_resource;
354		}
355
356		if (p && insert_resource(p, r)) {
357			dev_err(&pdev->dev, "failed to claim resource %d\n", i);
358			ret = -EBUSY;
359			goto failed;
360		}
361	}
362
363	pr_debug("Registering platform device '%s'. Parent at %s\n",
364		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
365
366	ret = device_add(&pdev->dev);
367	if (ret == 0)
368		return ret;
369
370 failed:
371	if (pdev->id_auto) {
372		ida_simple_remove(&platform_devid_ida, pdev->id);
373		pdev->id = PLATFORM_DEVID_AUTO;
374	}
375
376	while (--i >= 0) {
377		struct resource *r = &pdev->resource[i];
378		if (r->parent)
379			release_resource(r);
380	}
381
382 err_out:
383	return ret;
384}
385EXPORT_SYMBOL_GPL(platform_device_add);
386
387/**
388 * platform_device_del - remove a platform-level device
389 * @pdev: platform device we're removing
390 *
391 * Note that this function will also release all memory- and port-based
392 * resources owned by the device (@dev->resource).  This function must
393 * _only_ be externally called in error cases.  All other usage is a bug.
394 */
395void platform_device_del(struct platform_device *pdev)
396{
397	int i;
398
399	if (pdev) {
400		device_del(&pdev->dev);
401
402		if (pdev->id_auto) {
403			ida_simple_remove(&platform_devid_ida, pdev->id);
404			pdev->id = PLATFORM_DEVID_AUTO;
405		}
406
407		for (i = 0; i < pdev->num_resources; i++) {
408			struct resource *r = &pdev->resource[i];
409			if (r->parent)
410				release_resource(r);
411		}
412	}
413}
414EXPORT_SYMBOL_GPL(platform_device_del);
415
416/**
417 * platform_device_register - add a platform-level device
418 * @pdev: platform device we're adding
419 */
420int platform_device_register(struct platform_device *pdev)
421{
422	device_initialize(&pdev->dev);
423	arch_setup_pdev_archdata(pdev);
424	return platform_device_add(pdev);
425}
426EXPORT_SYMBOL_GPL(platform_device_register);
427
428/**
429 * platform_device_unregister - unregister a platform-level device
430 * @pdev: platform device we're unregistering
431 *
432 * Unregistration is done in 2 steps. First we release all resources
433 * and remove it from the subsystem, then we drop reference count by
434 * calling platform_device_put().
435 */
436void platform_device_unregister(struct platform_device *pdev)
437{
438	platform_device_del(pdev);
439	platform_device_put(pdev);
440}
441EXPORT_SYMBOL_GPL(platform_device_unregister);
442
443/**
444 * platform_device_register_full - add a platform-level device with
445 * resources and platform-specific data
446 *
447 * @pdevinfo: data used to create device
448 *
449 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
450 */
451struct platform_device *platform_device_register_full(
452		const struct platform_device_info *pdevinfo)
453{
454	int ret = -ENOMEM;
455	struct platform_device *pdev;
456
457	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
458	if (!pdev)
459		goto err_alloc;
460
461	pdev->dev.parent = pdevinfo->parent;
462	pdev->dev.fwnode = pdevinfo->fwnode;
463
464	if (pdevinfo->dma_mask) {
465		/*
466		 * This memory isn't freed when the device is put,
467		 * I don't have a nice idea for that though.  Conceptually
468		 * dma_mask in struct device should not be a pointer.
469		 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
470		 */
471		pdev->dev.dma_mask =
472			kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
473		if (!pdev->dev.dma_mask)
474			goto err;
475
476		*pdev->dev.dma_mask = pdevinfo->dma_mask;
477		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
478	}
479
480	ret = platform_device_add_resources(pdev,
481			pdevinfo->res, pdevinfo->num_res);
482	if (ret)
483		goto err;
484
485	ret = platform_device_add_data(pdev,
486			pdevinfo->data, pdevinfo->size_data);
487	if (ret)
488		goto err;
489
490	ret = platform_device_add(pdev);
491	if (ret) {
492err:
493		ACPI_COMPANION_SET(&pdev->dev, NULL);
494		kfree(pdev->dev.dma_mask);
495
496err_alloc:
497		platform_device_put(pdev);
498		return ERR_PTR(ret);
499	}
500
501	return pdev;
502}
503EXPORT_SYMBOL_GPL(platform_device_register_full);
504
505static int platform_drv_probe(struct device *_dev)
506{
507	struct platform_driver *drv = to_platform_driver(_dev->driver);
508	struct platform_device *dev = to_platform_device(_dev);
509	int ret;
510
511	ret = of_clk_set_defaults(_dev->of_node, false);
512	if (ret < 0)
513		return ret;
514
515	ret = dev_pm_domain_attach(_dev, true);
516	if (ret != -EPROBE_DEFER) {
517		ret = drv->probe(dev);
518		if (ret)
519			dev_pm_domain_detach(_dev, true);
520	}
521
522	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
523		dev_warn(_dev, "probe deferral not supported\n");
524		ret = -ENXIO;
525	}
526
527	return ret;
528}
529
530static int platform_drv_probe_fail(struct device *_dev)
531{
532	return -ENXIO;
533}
534
535static int platform_drv_remove(struct device *_dev)
536{
537	struct platform_driver *drv = to_platform_driver(_dev->driver);
538	struct platform_device *dev = to_platform_device(_dev);
539	int ret;
540
541	ret = drv->remove(dev);
542	dev_pm_domain_detach(_dev, true);
543
544	return ret;
545}
546
547static void platform_drv_shutdown(struct device *_dev)
548{
549	struct platform_driver *drv = to_platform_driver(_dev->driver);
550	struct platform_device *dev = to_platform_device(_dev);
551
552	drv->shutdown(dev);
553	dev_pm_domain_detach(_dev, true);
554}
555
556/**
557 * __platform_driver_register - register a driver for platform-level devices
558 * @drv: platform driver structure
559 * @owner: owning module/driver
560 */
561int __platform_driver_register(struct platform_driver *drv,
562				struct module *owner)
563{
564	drv->driver.owner = owner;
565	drv->driver.bus = &platform_bus_type;
566	if (drv->probe)
567		drv->driver.probe = platform_drv_probe;
568	if (drv->remove)
569		drv->driver.remove = platform_drv_remove;
570	if (drv->shutdown)
571		drv->driver.shutdown = platform_drv_shutdown;
572
573	return driver_register(&drv->driver);
574}
575EXPORT_SYMBOL_GPL(__platform_driver_register);
576
577/**
578 * platform_driver_unregister - unregister a driver for platform-level devices
579 * @drv: platform driver structure
580 */
581void platform_driver_unregister(struct platform_driver *drv)
582{
583	driver_unregister(&drv->driver);
584}
585EXPORT_SYMBOL_GPL(platform_driver_unregister);
586
587/**
588 * __platform_driver_probe - register driver for non-hotpluggable device
589 * @drv: platform driver structure
590 * @probe: the driver probe routine, probably from an __init section
591 * @module: module which will be the owner of the driver
592 *
593 * Use this instead of platform_driver_register() when you know the device
594 * is not hotpluggable and has already been registered, and you want to
595 * remove its run-once probe() infrastructure from memory after the driver
596 * has bound to the device.
597 *
598 * One typical use for this would be with drivers for controllers integrated
599 * into system-on-chip processors, where the controller devices have been
600 * configured as part of board setup.
601 *
602 * Note that this is incompatible with deferred probing.
603 *
604 * Returns zero if the driver registered and bound to a device, else returns
605 * a negative error code and with the driver not registered.
606 */
607int __init_or_module __platform_driver_probe(struct platform_driver *drv,
608		int (*probe)(struct platform_device *), struct module *module)
609{
610	int retval, code;
611
612	/*
613	 * Prevent driver from requesting probe deferral to avoid further
614	 * futile probe attempts.
615	 */
616	drv->prevent_deferred_probe = true;
617
618	/* make sure driver won't have bind/unbind attributes */
619	drv->driver.suppress_bind_attrs = true;
620
621	/* temporary section violation during probe() */
622	drv->probe = probe;
623	retval = code = __platform_driver_register(drv, module);
624
625	/*
626	 * Fixup that section violation, being paranoid about code scanning
627	 * the list of drivers in order to probe new devices.  Check to see
628	 * if the probe was successful, and make sure any forced probes of
629	 * new devices fail.
630	 */
631	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
632	drv->probe = NULL;
633	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
634		retval = -ENODEV;
635	drv->driver.probe = platform_drv_probe_fail;
636	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
637
638	if (code != retval)
639		platform_driver_unregister(drv);
640	return retval;
641}
642EXPORT_SYMBOL_GPL(__platform_driver_probe);
643
644/**
645 * __platform_create_bundle - register driver and create corresponding device
646 * @driver: platform driver structure
647 * @probe: the driver probe routine, probably from an __init section
648 * @res: set of resources that needs to be allocated for the device
649 * @n_res: number of resources
650 * @data: platform specific data for this platform device
651 * @size: size of platform specific data
652 * @module: module which will be the owner of the driver
653 *
654 * Use this in legacy-style modules that probe hardware directly and
655 * register a single platform device and corresponding platform driver.
656 *
657 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
658 */
659struct platform_device * __init_or_module __platform_create_bundle(
660			struct platform_driver *driver,
661			int (*probe)(struct platform_device *),
662			struct resource *res, unsigned int n_res,
663			const void *data, size_t size, struct module *module)
664{
665	struct platform_device *pdev;
666	int error;
667
668	pdev = platform_device_alloc(driver->driver.name, -1);
669	if (!pdev) {
670		error = -ENOMEM;
671		goto err_out;
672	}
673
674	error = platform_device_add_resources(pdev, res, n_res);
675	if (error)
676		goto err_pdev_put;
677
678	error = platform_device_add_data(pdev, data, size);
679	if (error)
680		goto err_pdev_put;
681
682	error = platform_device_add(pdev);
683	if (error)
684		goto err_pdev_put;
685
686	error = __platform_driver_probe(driver, probe, module);
687	if (error)
688		goto err_pdev_del;
689
690	return pdev;
691
692err_pdev_del:
693	platform_device_del(pdev);
694err_pdev_put:
695	platform_device_put(pdev);
696err_out:
697	return ERR_PTR(error);
698}
699EXPORT_SYMBOL_GPL(__platform_create_bundle);
700
701/* modalias support enables more hands-off userspace setup:
702 * (a) environment variable lets new-style hotplug events work once system is
703 *     fully running:  "modprobe $MODALIAS"
704 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
705 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
706 */
707static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
708			     char *buf)
709{
710	struct platform_device	*pdev = to_platform_device(dev);
711	int len;
712
713	len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
714	if (len != -ENODEV)
715		return len;
716
717	len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
718	if (len != -ENODEV)
719		return len;
720
721	len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
722
723	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
724}
725static DEVICE_ATTR_RO(modalias);
726
727static ssize_t driver_override_store(struct device *dev,
728				     struct device_attribute *attr,
729				     const char *buf, size_t count)
730{
731	struct platform_device *pdev = to_platform_device(dev);
732	char *driver_override, *old = pdev->driver_override, *cp;
733
734	if (count > PATH_MAX)
735		return -EINVAL;
736
737	driver_override = kstrndup(buf, count, GFP_KERNEL);
738	if (!driver_override)
739		return -ENOMEM;
740
741	cp = strchr(driver_override, '\n');
742	if (cp)
743		*cp = '\0';
744
745	if (strlen(driver_override)) {
746		pdev->driver_override = driver_override;
747	} else {
748		kfree(driver_override);
749		pdev->driver_override = NULL;
750	}
751
752	kfree(old);
753
754	return count;
755}
756
757static ssize_t driver_override_show(struct device *dev,
758				    struct device_attribute *attr, char *buf)
759{
760	struct platform_device *pdev = to_platform_device(dev);
761
762	return sprintf(buf, "%s\n", pdev->driver_override);
763}
764static DEVICE_ATTR_RW(driver_override);
765
766
767static struct attribute *platform_dev_attrs[] = {
768	&dev_attr_modalias.attr,
769	&dev_attr_driver_override.attr,
770	NULL,
771};
772ATTRIBUTE_GROUPS(platform_dev);
773
774static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
775{
776	struct platform_device	*pdev = to_platform_device(dev);
777	int rc;
778
779	/* Some devices have extra OF data and an OF-style MODALIAS */
780	rc = of_device_uevent_modalias(dev, env);
781	if (rc != -ENODEV)
782		return rc;
783
784	rc = acpi_device_uevent_modalias(dev, env);
785	if (rc != -ENODEV)
786		return rc;
787
788	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
789			pdev->name);
790	return 0;
791}
792
793static const struct platform_device_id *platform_match_id(
794			const struct platform_device_id *id,
795			struct platform_device *pdev)
796{
797	while (id->name[0]) {
798		if (strcmp(pdev->name, id->name) == 0) {
799			pdev->id_entry = id;
800			return id;
801		}
802		id++;
803	}
804	return NULL;
805}
806
807/**
808 * platform_match - bind platform device to platform driver.
809 * @dev: device.
810 * @drv: driver.
811 *
812 * Platform device IDs are assumed to be encoded like this:
813 * "<name><instance>", where <name> is a short description of the type of
814 * device, like "pci" or "floppy", and <instance> is the enumerated
815 * instance of the device, like '0' or '42'.  Driver IDs are simply
816 * "<name>".  So, extract the <name> from the platform_device structure,
817 * and compare it against the name of the driver. Return whether they match
818 * or not.
819 */
820static int platform_match(struct device *dev, struct device_driver *drv)
821{
822	struct platform_device *pdev = to_platform_device(dev);
823	struct platform_driver *pdrv = to_platform_driver(drv);
824
825	/* When driver_override is set, only bind to the matching driver */
826	if (pdev->driver_override)
827		return !strcmp(pdev->driver_override, drv->name);
828
829	/* Attempt an OF style match first */
830	if (of_driver_match_device(dev, drv))
831		return 1;
832
833	/* Then try ACPI style match */
834	if (acpi_driver_match_device(dev, drv))
835		return 1;
836
837	/* Then try to match against the id table */
838	if (pdrv->id_table)
839		return platform_match_id(pdrv->id_table, pdev) != NULL;
840
841	/* fall-back to driver name match */
842	return (strcmp(pdev->name, drv->name) == 0);
843}
844
845#ifdef CONFIG_PM_SLEEP
846
847static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
848{
849	struct platform_driver *pdrv = to_platform_driver(dev->driver);
850	struct platform_device *pdev = to_platform_device(dev);
851	int ret = 0;
852
853	if (dev->driver && pdrv->suspend)
854		ret = pdrv->suspend(pdev, mesg);
855
856	return ret;
857}
858
859static int platform_legacy_resume(struct device *dev)
860{
861	struct platform_driver *pdrv = to_platform_driver(dev->driver);
862	struct platform_device *pdev = to_platform_device(dev);
863	int ret = 0;
864
865	if (dev->driver && pdrv->resume)
866		ret = pdrv->resume(pdev);
867
868	return ret;
869}
870
871#endif /* CONFIG_PM_SLEEP */
872
873#ifdef CONFIG_SUSPEND
874
875int platform_pm_suspend(struct device *dev)
876{
877	struct device_driver *drv = dev->driver;
878	int ret = 0;
879
880	if (!drv)
881		return 0;
882
883	if (drv->pm) {
884		if (drv->pm->suspend)
885			ret = drv->pm->suspend(dev);
886	} else {
887		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
888	}
889
890	return ret;
891}
892
893int platform_pm_resume(struct device *dev)
894{
895	struct device_driver *drv = dev->driver;
896	int ret = 0;
897
898	if (!drv)
899		return 0;
900
901	if (drv->pm) {
902		if (drv->pm->resume)
903			ret = drv->pm->resume(dev);
904	} else {
905		ret = platform_legacy_resume(dev);
906	}
907
908	return ret;
909}
910
911#endif /* CONFIG_SUSPEND */
912
913#ifdef CONFIG_HIBERNATE_CALLBACKS
914
915int platform_pm_freeze(struct device *dev)
916{
917	struct device_driver *drv = dev->driver;
918	int ret = 0;
919
920	if (!drv)
921		return 0;
922
923	if (drv->pm) {
924		if (drv->pm->freeze)
925			ret = drv->pm->freeze(dev);
926	} else {
927		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
928	}
929
930	return ret;
931}
932
933int platform_pm_thaw(struct device *dev)
934{
935	struct device_driver *drv = dev->driver;
936	int ret = 0;
937
938	if (!drv)
939		return 0;
940
941	if (drv->pm) {
942		if (drv->pm->thaw)
943			ret = drv->pm->thaw(dev);
944	} else {
945		ret = platform_legacy_resume(dev);
946	}
947
948	return ret;
949}
950
951int platform_pm_poweroff(struct device *dev)
952{
953	struct device_driver *drv = dev->driver;
954	int ret = 0;
955
956	if (!drv)
957		return 0;
958
959	if (drv->pm) {
960		if (drv->pm->poweroff)
961			ret = drv->pm->poweroff(dev);
962	} else {
963		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
964	}
965
966	return ret;
967}
968
969int platform_pm_restore(struct device *dev)
970{
971	struct device_driver *drv = dev->driver;
972	int ret = 0;
973
974	if (!drv)
975		return 0;
976
977	if (drv->pm) {
978		if (drv->pm->restore)
979			ret = drv->pm->restore(dev);
980	} else {
981		ret = platform_legacy_resume(dev);
982	}
983
984	return ret;
985}
986
987#endif /* CONFIG_HIBERNATE_CALLBACKS */
988
989static const struct dev_pm_ops platform_dev_pm_ops = {
990	.runtime_suspend = pm_generic_runtime_suspend,
991	.runtime_resume = pm_generic_runtime_resume,
992	USE_PLATFORM_PM_SLEEP_OPS
993};
994
995struct bus_type platform_bus_type = {
996	.name		= "platform",
997	.dev_groups	= platform_dev_groups,
998	.match		= platform_match,
999	.uevent		= platform_uevent,
1000	.pm		= &platform_dev_pm_ops,
1001};
1002EXPORT_SYMBOL_GPL(platform_bus_type);
1003
1004int __init platform_bus_init(void)
1005{
1006	int error;
1007
1008	early_platform_cleanup();
1009
1010	error = device_register(&platform_bus);
1011	if (error)
1012		return error;
1013	error =  bus_register(&platform_bus_type);
1014	if (error)
1015		device_unregister(&platform_bus);
1016	of_platform_register_reconfig_notifier();
1017	return error;
1018}
1019
1020#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1021u64 dma_get_required_mask(struct device *dev)
1022{
1023	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
1024	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1025	u64 mask;
1026
1027	if (!high_totalram) {
1028		/* convert to mask just covering totalram */
1029		low_totalram = (1 << (fls(low_totalram) - 1));
1030		low_totalram += low_totalram - 1;
1031		mask = low_totalram;
1032	} else {
1033		high_totalram = (1 << (fls(high_totalram) - 1));
1034		high_totalram += high_totalram - 1;
1035		mask = (((u64)high_totalram) << 32) + 0xffffffff;
1036	}
1037	return mask;
1038}
1039EXPORT_SYMBOL_GPL(dma_get_required_mask);
1040#endif
1041
1042static __initdata LIST_HEAD(early_platform_driver_list);
1043static __initdata LIST_HEAD(early_platform_device_list);
1044
1045/**
1046 * early_platform_driver_register - register early platform driver
1047 * @epdrv: early_platform driver structure
1048 * @buf: string passed from early_param()
1049 *
1050 * Helper function for early_platform_init() / early_platform_init_buffer()
1051 */
1052int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1053					  char *buf)
1054{
1055	char *tmp;
1056	int n;
1057
1058	/* Simply add the driver to the end of the global list.
1059	 * Drivers will by default be put on the list in compiled-in order.
1060	 */
1061	if (!epdrv->list.next) {
1062		INIT_LIST_HEAD(&epdrv->list);
1063		list_add_tail(&epdrv->list, &early_platform_driver_list);
1064	}
1065
1066	/* If the user has specified device then make sure the driver
1067	 * gets prioritized. The driver of the last device specified on
1068	 * command line will be put first on the list.
1069	 */
1070	n = strlen(epdrv->pdrv->driver.name);
1071	if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1072		list_move(&epdrv->list, &early_platform_driver_list);
1073
1074		/* Allow passing parameters after device name */
1075		if (buf[n] == '\0' || buf[n] == ',')
1076			epdrv->requested_id = -1;
1077		else {
1078			epdrv->requested_id = simple_strtoul(&buf[n + 1],
1079							     &tmp, 10);
1080
1081			if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1082				epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1083				n = 0;
1084			} else
1085				n += strcspn(&buf[n + 1], ",") + 1;
1086		}
1087
1088		if (buf[n] == ',')
1089			n++;
1090
1091		if (epdrv->bufsize) {
1092			memcpy(epdrv->buffer, &buf[n],
1093			       min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1094			epdrv->buffer[epdrv->bufsize - 1] = '\0';
1095		}
1096	}
1097
1098	return 0;
1099}
1100
1101/**
1102 * early_platform_add_devices - adds a number of early platform devices
1103 * @devs: array of early platform devices to add
1104 * @num: number of early platform devices in array
1105 *
1106 * Used by early architecture code to register early platform devices and
1107 * their platform data.
1108 */
1109void __init early_platform_add_devices(struct platform_device **devs, int num)
1110{
1111	struct device *dev;
1112	int i;
1113
1114	/* simply add the devices to list */
1115	for (i = 0; i < num; i++) {
1116		dev = &devs[i]->dev;
1117
1118		if (!dev->devres_head.next) {
1119			pm_runtime_early_init(dev);
1120			INIT_LIST_HEAD(&dev->devres_head);
1121			list_add_tail(&dev->devres_head,
1122				      &early_platform_device_list);
1123		}
1124	}
1125}
1126
1127/**
1128 * early_platform_driver_register_all - register early platform drivers
1129 * @class_str: string to identify early platform driver class
1130 *
1131 * Used by architecture code to register all early platform drivers
1132 * for a certain class. If omitted then only early platform drivers
1133 * with matching kernel command line class parameters will be registered.
1134 */
1135void __init early_platform_driver_register_all(char *class_str)
1136{
1137	/* The "class_str" parameter may or may not be present on the kernel
1138	 * command line. If it is present then there may be more than one
1139	 * matching parameter.
1140	 *
1141	 * Since we register our early platform drivers using early_param()
1142	 * we need to make sure that they also get registered in the case
1143	 * when the parameter is missing from the kernel command line.
1144	 *
1145	 * We use parse_early_options() to make sure the early_param() gets
1146	 * called at least once. The early_param() may be called more than
1147	 * once since the name of the preferred device may be specified on
1148	 * the kernel command line. early_platform_driver_register() handles
1149	 * this case for us.
1150	 */
1151	parse_early_options(class_str);
1152}
1153
1154/**
1155 * early_platform_match - find early platform device matching driver
1156 * @epdrv: early platform driver structure
1157 * @id: id to match against
1158 */
1159static struct platform_device * __init
1160early_platform_match(struct early_platform_driver *epdrv, int id)
1161{
1162	struct platform_device *pd;
1163
1164	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1165		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1166			if (pd->id == id)
1167				return pd;
1168
1169	return NULL;
1170}
1171
1172/**
1173 * early_platform_left - check if early platform driver has matching devices
1174 * @epdrv: early platform driver structure
1175 * @id: return true if id or above exists
1176 */
1177static int __init early_platform_left(struct early_platform_driver *epdrv,
1178				       int id)
1179{
1180	struct platform_device *pd;
1181
1182	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1183		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1184			if (pd->id >= id)
1185				return 1;
1186
1187	return 0;
1188}
1189
1190/**
1191 * early_platform_driver_probe_id - probe drivers matching class_str and id
1192 * @class_str: string to identify early platform driver class
1193 * @id: id to match against
1194 * @nr_probe: number of platform devices to successfully probe before exiting
1195 */
1196static int __init early_platform_driver_probe_id(char *class_str,
1197						 int id,
1198						 int nr_probe)
1199{
1200	struct early_platform_driver *epdrv;
1201	struct platform_device *match;
1202	int match_id;
1203	int n = 0;
1204	int left = 0;
1205
1206	list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1207		/* only use drivers matching our class_str */
1208		if (strcmp(class_str, epdrv->class_str))
1209			continue;
1210
1211		if (id == -2) {
1212			match_id = epdrv->requested_id;
1213			left = 1;
1214
1215		} else {
1216			match_id = id;
1217			left += early_platform_left(epdrv, id);
1218
1219			/* skip requested id */
1220			switch (epdrv->requested_id) {
1221			case EARLY_PLATFORM_ID_ERROR:
1222			case EARLY_PLATFORM_ID_UNSET:
1223				break;
1224			default:
1225				if (epdrv->requested_id == id)
1226					match_id = EARLY_PLATFORM_ID_UNSET;
1227			}
1228		}
1229
1230		switch (match_id) {
1231		case EARLY_PLATFORM_ID_ERROR:
1232			pr_warn("%s: unable to parse %s parameter\n",
1233				class_str, epdrv->pdrv->driver.name);
1234			/* fall-through */
1235		case EARLY_PLATFORM_ID_UNSET:
1236			match = NULL;
1237			break;
1238		default:
1239			match = early_platform_match(epdrv, match_id);
1240		}
1241
1242		if (match) {
1243			/*
1244			 * Set up a sensible init_name to enable
1245			 * dev_name() and others to be used before the
1246			 * rest of the driver core is initialized.
1247			 */
1248			if (!match->dev.init_name && slab_is_available()) {
1249				if (match->id != -1)
1250					match->dev.init_name =
1251						kasprintf(GFP_KERNEL, "%s.%d",
1252							  match->name,
1253							  match->id);
1254				else
1255					match->dev.init_name =
1256						kasprintf(GFP_KERNEL, "%s",
1257							  match->name);
1258
1259				if (!match->dev.init_name)
1260					return -ENOMEM;
1261			}
1262
1263			if (epdrv->pdrv->probe(match))
1264				pr_warn("%s: unable to probe %s early.\n",
1265					class_str, match->name);
1266			else
1267				n++;
1268		}
1269
1270		if (n >= nr_probe)
1271			break;
1272	}
1273
1274	if (left)
1275		return n;
1276	else
1277		return -ENODEV;
1278}
1279
1280/**
1281 * early_platform_driver_probe - probe a class of registered drivers
1282 * @class_str: string to identify early platform driver class
1283 * @nr_probe: number of platform devices to successfully probe before exiting
1284 * @user_only: only probe user specified early platform devices
1285 *
1286 * Used by architecture code to probe registered early platform drivers
1287 * within a certain class. For probe to happen a registered early platform
1288 * device matching a registered early platform driver is needed.
1289 */
1290int __init early_platform_driver_probe(char *class_str,
1291				       int nr_probe,
1292				       int user_only)
1293{
1294	int k, n, i;
1295
1296	n = 0;
1297	for (i = -2; n < nr_probe; i++) {
1298		k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1299
1300		if (k < 0)
1301			break;
1302
1303		n += k;
1304
1305		if (user_only)
1306			break;
1307	}
1308
1309	return n;
1310}
1311
1312/**
1313 * early_platform_cleanup - clean up early platform code
1314 */
1315void __init early_platform_cleanup(void)
1316{
1317	struct platform_device *pd, *pd2;
1318
1319	/* clean up the devres list used to chain devices */
1320	list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1321				 dev.devres_head) {
1322		list_del(&pd->dev.devres_head);
1323		memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1324	}
1325}
1326
1327