Root/drivers/base/platform.c

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/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/idr.h>
24#include <linux/acpi.h>
25
26#include "base.h"
27#include "power/power.h"
28
29/* For automatically allocated device IDs */
30static DEFINE_IDA(platform_devid_ida);
31
32#define to_platform_driver(drv) (container_of((drv), struct platform_driver, \
33                 driver))
34
35struct device platform_bus = {
36    .init_name = "platform",
37};
38EXPORT_SYMBOL_GPL(platform_bus);
39
40/**
41 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
42 * @pdev: platform device
43 *
44 * This is called before platform_device_add() such that any pdev_archdata may
45 * be setup before the platform_notifier is called. So if a user needs to
46 * manipulate any relevant information in the pdev_archdata they can do:
47 *
48 * platform_device_alloc()
49 * ... manipulate ...
50 * platform_device_add()
51 *
52 * And if they don't care they can just call platform_device_register() and
53 * everything will just work out.
54 */
55void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
56{
57}
58
59/**
60 * platform_get_resource - get a resource for a device
61 * @dev: platform device
62 * @type: resource type
63 * @num: resource index
64 */
65struct resource *platform_get_resource(struct platform_device *dev,
66                       unsigned int type, unsigned int num)
67{
68    int i;
69
70    for (i = 0; i < dev->num_resources; i++) {
71        struct resource *r = &dev->resource[i];
72
73        if (type == resource_type(r) && num-- == 0)
74            return r;
75    }
76    return NULL;
77}
78EXPORT_SYMBOL_GPL(platform_get_resource);
79
80/**
81 * platform_get_irq - get an IRQ for a device
82 * @dev: platform device
83 * @num: IRQ number index
84 */
85int platform_get_irq(struct platform_device *dev, unsigned int num)
86{
87#ifdef CONFIG_SPARC
88    /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
89    if (!dev || num >= dev->archdata.num_irqs)
90        return -ENXIO;
91    return dev->archdata.irqs[num];
92#else
93    struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
94
95    return r ? r->start : -ENXIO;
96#endif
97}
98EXPORT_SYMBOL_GPL(platform_get_irq);
99
100/**
101 * platform_get_resource_byname - get a resource for a device by name
102 * @dev: platform device
103 * @type: resource type
104 * @name: resource name
105 */
106struct resource *platform_get_resource_byname(struct platform_device *dev,
107                          unsigned int type,
108                          const char *name)
109{
110    int i;
111
112    for (i = 0; i < dev->num_resources; i++) {
113        struct resource *r = &dev->resource[i];
114
115        if (unlikely(!r->name))
116            continue;
117
118        if (type == resource_type(r) && !strcmp(r->name, name))
119            return r;
120    }
121    return NULL;
122}
123EXPORT_SYMBOL_GPL(platform_get_resource_byname);
124
125/**
126 * platform_get_irq_byname - get an IRQ for a device by name
127 * @dev: platform device
128 * @name: IRQ name
129 */
130int platform_get_irq_byname(struct platform_device *dev, const char *name)
131{
132    struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
133                              name);
134
135    return r ? r->start : -ENXIO;
136}
137EXPORT_SYMBOL_GPL(platform_get_irq_byname);
138
139/**
140 * platform_add_devices - add a numbers of platform devices
141 * @devs: array of platform devices to add
142 * @num: number of platform devices in array
143 */
144int platform_add_devices(struct platform_device **devs, int num)
145{
146    int i, ret = 0;
147
148    for (i = 0; i < num; i++) {
149        ret = platform_device_register(devs[i]);
150        if (ret) {
151            while (--i >= 0)
152                platform_device_unregister(devs[i]);
153            break;
154        }
155    }
156
157    return ret;
158}
159EXPORT_SYMBOL_GPL(platform_add_devices);
160
161struct platform_object {
162    struct platform_device pdev;
163    char name[1];
164};
165
166/**
167 * platform_device_put - destroy a platform device
168 * @pdev: platform device to free
169 *
170 * Free all memory associated with a platform device. This function must
171 * _only_ be externally called in error cases. All other usage is a bug.
172 */
173void platform_device_put(struct platform_device *pdev)
174{
175    if (pdev)
176        put_device(&pdev->dev);
177}
178EXPORT_SYMBOL_GPL(platform_device_put);
179
180static void platform_device_release(struct device *dev)
181{
182    struct platform_object *pa = container_of(dev, struct platform_object,
183                          pdev.dev);
184
185    of_device_node_put(&pa->pdev.dev);
186    kfree(pa->pdev.dev.platform_data);
187    kfree(pa->pdev.mfd_cell);
188    kfree(pa->pdev.resource);
189    kfree(pa);
190}
191
192/**
193 * platform_device_alloc - create a platform device
194 * @name: base name of the device we're adding
195 * @id: instance id
196 *
197 * Create a platform device object which can have other objects attached
198 * to it, and which will have attached objects freed when it is released.
199 */
200struct platform_device *platform_device_alloc(const char *name, int id)
201{
202    struct platform_object *pa;
203
204    pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
205    if (pa) {
206        strcpy(pa->name, name);
207        pa->pdev.name = pa->name;
208        pa->pdev.id = id;
209        device_initialize(&pa->pdev.dev);
210        pa->pdev.dev.release = platform_device_release;
211        arch_setup_pdev_archdata(&pa->pdev);
212    }
213
214    return pa ? &pa->pdev : NULL;
215}
216EXPORT_SYMBOL_GPL(platform_device_alloc);
217
218/**
219 * platform_device_add_resources - add resources to a platform device
220 * @pdev: platform device allocated by platform_device_alloc to add resources to
221 * @res: set of resources that needs to be allocated for the device
222 * @num: number of resources
223 *
224 * Add a copy of the resources to the platform device. The memory
225 * associated with the resources will be freed when the platform device is
226 * released.
227 */
228int platform_device_add_resources(struct platform_device *pdev,
229                  const struct resource *res, unsigned int num)
230{
231    struct resource *r = NULL;
232
233    if (res) {
234        r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
235        if (!r)
236            return -ENOMEM;
237    }
238
239    kfree(pdev->resource);
240    pdev->resource = r;
241    pdev->num_resources = num;
242    return 0;
243}
244EXPORT_SYMBOL_GPL(platform_device_add_resources);
245
246/**
247 * platform_device_add_data - add platform-specific data to a platform device
248 * @pdev: platform device allocated by platform_device_alloc to add resources to
249 * @data: platform specific data for this platform device
250 * @size: size of platform specific data
251 *
252 * Add a copy of platform specific data to the platform device's
253 * platform_data pointer. The memory associated with the platform data
254 * will be freed when the platform device is released.
255 */
256int platform_device_add_data(struct platform_device *pdev, const void *data,
257                 size_t size)
258{
259    void *d = NULL;
260
261    if (data) {
262        d = kmemdup(data, size, GFP_KERNEL);
263        if (!d)
264            return -ENOMEM;
265    }
266
267    kfree(pdev->dev.platform_data);
268    pdev->dev.platform_data = d;
269    return 0;
270}
271EXPORT_SYMBOL_GPL(platform_device_add_data);
272
273/**
274 * platform_device_add - add a platform device to device hierarchy
275 * @pdev: platform device we're adding
276 *
277 * This is part 2 of platform_device_register(), though may be called
278 * separately _iff_ pdev was allocated by platform_device_alloc().
279 */
280int platform_device_add(struct platform_device *pdev)
281{
282    int i, ret;
283
284    if (!pdev)
285        return -EINVAL;
286
287    if (!pdev->dev.parent)
288        pdev->dev.parent = &platform_bus;
289
290    pdev->dev.bus = &platform_bus_type;
291
292    switch (pdev->id) {
293    default:
294        dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
295        break;
296    case PLATFORM_DEVID_NONE:
297        dev_set_name(&pdev->dev, "%s", pdev->name);
298        break;
299    case PLATFORM_DEVID_AUTO:
300        /*
301         * Automatically allocated device ID. We mark it as such so
302         * that we remember it must be freed, and we append a suffix
303         * to avoid namespace collision with explicit IDs.
304         */
305        ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
306        if (ret < 0)
307            goto err_out;
308        pdev->id = ret;
309        pdev->id_auto = true;
310        dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
311        break;
312    }
313
314    for (i = 0; i < pdev->num_resources; i++) {
315        struct resource *p, *r = &pdev->resource[i];
316
317        if (r->name == NULL)
318            r->name = dev_name(&pdev->dev);
319
320        p = r->parent;
321        if (!p) {
322            if (resource_type(r) == IORESOURCE_MEM)
323                p = &iomem_resource;
324            else if (resource_type(r) == IORESOURCE_IO)
325                p = &ioport_resource;
326        }
327
328        if (p && insert_resource(p, r)) {
329            printk(KERN_ERR
330                   "%s: failed to claim resource %d\n",
331                   dev_name(&pdev->dev), i);
332            ret = -EBUSY;
333            goto failed;
334        }
335    }
336
337    pr_debug("Registering platform device '%s'. Parent at %s\n",
338         dev_name(&pdev->dev), dev_name(pdev->dev.parent));
339
340    ret = device_add(&pdev->dev);
341    if (ret == 0)
342        return ret;
343
344 failed:
345    if (pdev->id_auto) {
346        ida_simple_remove(&platform_devid_ida, pdev->id);
347        pdev->id = PLATFORM_DEVID_AUTO;
348    }
349
350    while (--i >= 0) {
351        struct resource *r = &pdev->resource[i];
352        unsigned long type = resource_type(r);
353
354        if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
355            release_resource(r);
356    }
357
358 err_out:
359    return ret;
360}
361EXPORT_SYMBOL_GPL(platform_device_add);
362
363/**
364 * platform_device_del - remove a platform-level device
365 * @pdev: platform device we're removing
366 *
367 * Note that this function will also release all memory- and port-based
368 * resources owned by the device (@dev->resource). This function must
369 * _only_ be externally called in error cases. All other usage is a bug.
370 */
371void platform_device_del(struct platform_device *pdev)
372{
373    int i;
374
375    if (pdev) {
376        device_del(&pdev->dev);
377
378        if (pdev->id_auto) {
379            ida_simple_remove(&platform_devid_ida, pdev->id);
380            pdev->id = PLATFORM_DEVID_AUTO;
381        }
382
383        for (i = 0; i < pdev->num_resources; i++) {
384            struct resource *r = &pdev->resource[i];
385            unsigned long type = resource_type(r);
386
387            if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
388                release_resource(r);
389        }
390    }
391}
392EXPORT_SYMBOL_GPL(platform_device_del);
393
394/**
395 * platform_device_register - add a platform-level device
396 * @pdev: platform device we're adding
397 */
398int platform_device_register(struct platform_device *pdev)
399{
400    device_initialize(&pdev->dev);
401    arch_setup_pdev_archdata(pdev);
402    return platform_device_add(pdev);
403}
404EXPORT_SYMBOL_GPL(platform_device_register);
405
406/**
407 * platform_device_unregister - unregister a platform-level device
408 * @pdev: platform device we're unregistering
409 *
410 * Unregistration is done in 2 steps. First we release all resources
411 * and remove it from the subsystem, then we drop reference count by
412 * calling platform_device_put().
413 */
414void platform_device_unregister(struct platform_device *pdev)
415{
416    platform_device_del(pdev);
417    platform_device_put(pdev);
418}
419EXPORT_SYMBOL_GPL(platform_device_unregister);
420
421/**
422 * platform_device_register_full - add a platform-level device with
423 * resources and platform-specific data
424 *
425 * @pdevinfo: data used to create device
426 *
427 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
428 */
429struct platform_device *platform_device_register_full(
430        const struct platform_device_info *pdevinfo)
431{
432    int ret = -ENOMEM;
433    struct platform_device *pdev;
434
435    pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
436    if (!pdev)
437        goto err_alloc;
438
439    pdev->dev.parent = pdevinfo->parent;
440    ACPI_HANDLE_SET(&pdev->dev, pdevinfo->acpi_node.handle);
441
442    if (pdevinfo->dma_mask) {
443        /*
444         * This memory isn't freed when the device is put,
445         * I don't have a nice idea for that though. Conceptually
446         * dma_mask in struct device should not be a pointer.
447         * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
448         */
449        pdev->dev.dma_mask =
450            kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
451        if (!pdev->dev.dma_mask)
452            goto err;
453
454        *pdev->dev.dma_mask = pdevinfo->dma_mask;
455        pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
456    }
457
458    ret = platform_device_add_resources(pdev,
459            pdevinfo->res, pdevinfo->num_res);
460    if (ret)
461        goto err;
462
463    ret = platform_device_add_data(pdev,
464            pdevinfo->data, pdevinfo->size_data);
465    if (ret)
466        goto err;
467
468    ret = platform_device_add(pdev);
469    if (ret) {
470err:
471        ACPI_HANDLE_SET(&pdev->dev, NULL);
472        kfree(pdev->dev.dma_mask);
473
474err_alloc:
475        platform_device_put(pdev);
476        return ERR_PTR(ret);
477    }
478
479    return pdev;
480}
481EXPORT_SYMBOL_GPL(platform_device_register_full);
482
483static int platform_drv_probe(struct device *_dev)
484{
485    struct platform_driver *drv = to_platform_driver(_dev->driver);
486    struct platform_device *dev = to_platform_device(_dev);
487    int ret;
488
489    if (ACPI_HANDLE(_dev))
490        acpi_dev_pm_attach(_dev, true);
491
492    ret = drv->probe(dev);
493    if (ret && ACPI_HANDLE(_dev))
494        acpi_dev_pm_detach(_dev, true);
495
496    return ret;
497}
498
499static int platform_drv_probe_fail(struct device *_dev)
500{
501    return -ENXIO;
502}
503
504static int platform_drv_remove(struct device *_dev)
505{
506    struct platform_driver *drv = to_platform_driver(_dev->driver);
507    struct platform_device *dev = to_platform_device(_dev);
508    int ret;
509
510    ret = drv->remove(dev);
511    if (ACPI_HANDLE(_dev))
512        acpi_dev_pm_detach(_dev, true);
513
514    return ret;
515}
516
517static void platform_drv_shutdown(struct device *_dev)
518{
519    struct platform_driver *drv = to_platform_driver(_dev->driver);
520    struct platform_device *dev = to_platform_device(_dev);
521
522    drv->shutdown(dev);
523    if (ACPI_HANDLE(_dev))
524        acpi_dev_pm_detach(_dev, true);
525}
526
527/**
528 * platform_driver_register - register a driver for platform-level devices
529 * @drv: platform driver structure
530 */
531int platform_driver_register(struct platform_driver *drv)
532{
533    drv->driver.bus = &platform_bus_type;
534    if (drv->probe)
535        drv->driver.probe = platform_drv_probe;
536    if (drv->remove)
537        drv->driver.remove = platform_drv_remove;
538    if (drv->shutdown)
539        drv->driver.shutdown = platform_drv_shutdown;
540
541    return driver_register(&drv->driver);
542}
543EXPORT_SYMBOL_GPL(platform_driver_register);
544
545/**
546 * platform_driver_unregister - unregister a driver for platform-level devices
547 * @drv: platform driver structure
548 */
549void platform_driver_unregister(struct platform_driver *drv)
550{
551    driver_unregister(&drv->driver);
552}
553EXPORT_SYMBOL_GPL(platform_driver_unregister);
554
555/**
556 * platform_driver_probe - register driver for non-hotpluggable device
557 * @drv: platform driver structure
558 * @probe: the driver probe routine, probably from an __init section
559 *
560 * Use this instead of platform_driver_register() when you know the device
561 * is not hotpluggable and has already been registered, and you want to
562 * remove its run-once probe() infrastructure from memory after the driver
563 * has bound to the device.
564 *
565 * One typical use for this would be with drivers for controllers integrated
566 * into system-on-chip processors, where the controller devices have been
567 * configured as part of board setup.
568 *
569 * Returns zero if the driver registered and bound to a device, else returns
570 * a negative error code and with the driver not registered.
571 */
572int __init_or_module platform_driver_probe(struct platform_driver *drv,
573        int (*probe)(struct platform_device *))
574{
575    int retval, code;
576
577    /* make sure driver won't have bind/unbind attributes */
578    drv->driver.suppress_bind_attrs = true;
579
580    /* temporary section violation during probe() */
581    drv->probe = probe;
582    retval = code = platform_driver_register(drv);
583
584    /*
585     * Fixup that section violation, being paranoid about code scanning
586     * the list of drivers in order to probe new devices. Check to see
587     * if the probe was successful, and make sure any forced probes of
588     * new devices fail.
589     */
590    spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
591    drv->probe = NULL;
592    if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
593        retval = -ENODEV;
594    drv->driver.probe = platform_drv_probe_fail;
595    spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
596
597    if (code != retval)
598        platform_driver_unregister(drv);
599    return retval;
600}
601EXPORT_SYMBOL_GPL(platform_driver_probe);
602
603/**
604 * platform_create_bundle - register driver and create corresponding device
605 * @driver: platform driver structure
606 * @probe: the driver probe routine, probably from an __init section
607 * @res: set of resources that needs to be allocated for the device
608 * @n_res: number of resources
609 * @data: platform specific data for this platform device
610 * @size: size of platform specific data
611 *
612 * Use this in legacy-style modules that probe hardware directly and
613 * register a single platform device and corresponding platform driver.
614 *
615 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
616 */
617struct platform_device * __init_or_module platform_create_bundle(
618            struct platform_driver *driver,
619            int (*probe)(struct platform_device *),
620            struct resource *res, unsigned int n_res,
621            const void *data, size_t size)
622{
623    struct platform_device *pdev;
624    int error;
625
626    pdev = platform_device_alloc(driver->driver.name, -1);
627    if (!pdev) {
628        error = -ENOMEM;
629        goto err_out;
630    }
631
632    error = platform_device_add_resources(pdev, res, n_res);
633    if (error)
634        goto err_pdev_put;
635
636    error = platform_device_add_data(pdev, data, size);
637    if (error)
638        goto err_pdev_put;
639
640    error = platform_device_add(pdev);
641    if (error)
642        goto err_pdev_put;
643
644    error = platform_driver_probe(driver, probe);
645    if (error)
646        goto err_pdev_del;
647
648    return pdev;
649
650err_pdev_del:
651    platform_device_del(pdev);
652err_pdev_put:
653    platform_device_put(pdev);
654err_out:
655    return ERR_PTR(error);
656}
657EXPORT_SYMBOL_GPL(platform_create_bundle);
658
659/* modalias support enables more hands-off userspace setup:
660 * (a) environment variable lets new-style hotplug events work once system is
661 * fully running: "modprobe $MODALIAS"
662 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
663 * mishandled before system is fully running: "modprobe $(cat modalias)"
664 */
665static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
666                 char *buf)
667{
668    struct platform_device *pdev = to_platform_device(dev);
669    int len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
670
671    return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
672}
673
674static struct device_attribute platform_dev_attrs[] = {
675    __ATTR_RO(modalias),
676    __ATTR_NULL,
677};
678
679static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
680{
681    struct platform_device *pdev = to_platform_device(dev);
682    int rc;
683
684    /* Some devices have extra OF data and an OF-style MODALIAS */
685    rc = of_device_uevent_modalias(dev,env);
686    if (rc != -ENODEV)
687        return rc;
688
689    add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
690            pdev->name);
691    return 0;
692}
693
694static const struct platform_device_id *platform_match_id(
695            const struct platform_device_id *id,
696            struct platform_device *pdev)
697{
698    while (id->name[0]) {
699        if (strcmp(pdev->name, id->name) == 0) {
700            pdev->id_entry = id;
701            return id;
702        }
703        id++;
704    }
705    return NULL;
706}
707
708/**
709 * platform_match - bind platform device to platform driver.
710 * @dev: device.
711 * @drv: driver.
712 *
713 * Platform device IDs are assumed to be encoded like this:
714 * "<name><instance>", where <name> is a short description of the type of
715 * device, like "pci" or "floppy", and <instance> is the enumerated
716 * instance of the device, like '0' or '42'. Driver IDs are simply
717 * "<name>". So, extract the <name> from the platform_device structure,
718 * and compare it against the name of the driver. Return whether they match
719 * or not.
720 */
721static int platform_match(struct device *dev, struct device_driver *drv)
722{
723    struct platform_device *pdev = to_platform_device(dev);
724    struct platform_driver *pdrv = to_platform_driver(drv);
725
726    /* Attempt an OF style match first */
727    if (of_driver_match_device(dev, drv))
728        return 1;
729
730    /* Then try ACPI style match */
731    if (acpi_driver_match_device(dev, drv))
732        return 1;
733
734    /* Then try to match against the id table */
735    if (pdrv->id_table)
736        return platform_match_id(pdrv->id_table, pdev) != NULL;
737
738    /* fall-back to driver name match */
739    return (strcmp(pdev->name, drv->name) == 0);
740}
741
742#ifdef CONFIG_PM_SLEEP
743
744static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
745{
746    struct platform_driver *pdrv = to_platform_driver(dev->driver);
747    struct platform_device *pdev = to_platform_device(dev);
748    int ret = 0;
749
750    if (dev->driver && pdrv->suspend)
751        ret = pdrv->suspend(pdev, mesg);
752
753    return ret;
754}
755
756static int platform_legacy_resume(struct device *dev)
757{
758    struct platform_driver *pdrv = to_platform_driver(dev->driver);
759    struct platform_device *pdev = to_platform_device(dev);
760    int ret = 0;
761
762    if (dev->driver && pdrv->resume)
763        ret = pdrv->resume(pdev);
764
765    return ret;
766}
767
768#endif /* CONFIG_PM_SLEEP */
769
770#ifdef CONFIG_SUSPEND
771
772int platform_pm_suspend(struct device *dev)
773{
774    struct device_driver *drv = dev->driver;
775    int ret = 0;
776
777    if (!drv)
778        return 0;
779
780    if (drv->pm) {
781        if (drv->pm->suspend)
782            ret = drv->pm->suspend(dev);
783    } else {
784        ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
785    }
786
787    return ret;
788}
789
790int platform_pm_resume(struct device *dev)
791{
792    struct device_driver *drv = dev->driver;
793    int ret = 0;
794
795    if (!drv)
796        return 0;
797
798    if (drv->pm) {
799        if (drv->pm->resume)
800            ret = drv->pm->resume(dev);
801    } else {
802        ret = platform_legacy_resume(dev);
803    }
804
805    return ret;
806}
807
808#endif /* CONFIG_SUSPEND */
809
810#ifdef CONFIG_HIBERNATE_CALLBACKS
811
812int platform_pm_freeze(struct device *dev)
813{
814    struct device_driver *drv = dev->driver;
815    int ret = 0;
816
817    if (!drv)
818        return 0;
819
820    if (drv->pm) {
821        if (drv->pm->freeze)
822            ret = drv->pm->freeze(dev);
823    } else {
824        ret = platform_legacy_suspend(dev, PMSG_FREEZE);
825    }
826
827    return ret;
828}
829
830int platform_pm_thaw(struct device *dev)
831{
832    struct device_driver *drv = dev->driver;
833    int ret = 0;
834
835    if (!drv)
836        return 0;
837
838    if (drv->pm) {
839        if (drv->pm->thaw)
840            ret = drv->pm->thaw(dev);
841    } else {
842        ret = platform_legacy_resume(dev);
843    }
844
845    return ret;
846}
847
848int platform_pm_poweroff(struct device *dev)
849{
850    struct device_driver *drv = dev->driver;
851    int ret = 0;
852
853    if (!drv)
854        return 0;
855
856    if (drv->pm) {
857        if (drv->pm->poweroff)
858            ret = drv->pm->poweroff(dev);
859    } else {
860        ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
861    }
862
863    return ret;
864}
865
866int platform_pm_restore(struct device *dev)
867{
868    struct device_driver *drv = dev->driver;
869    int ret = 0;
870
871    if (!drv)
872        return 0;
873
874    if (drv->pm) {
875        if (drv->pm->restore)
876            ret = drv->pm->restore(dev);
877    } else {
878        ret = platform_legacy_resume(dev);
879    }
880
881    return ret;
882}
883
884#endif /* CONFIG_HIBERNATE_CALLBACKS */
885
886static const struct dev_pm_ops platform_dev_pm_ops = {
887    .runtime_suspend = pm_generic_runtime_suspend,
888    .runtime_resume = pm_generic_runtime_resume,
889    .runtime_idle = pm_generic_runtime_idle,
890    USE_PLATFORM_PM_SLEEP_OPS
891};
892
893struct bus_type platform_bus_type = {
894    .name = "platform",
895    .dev_attrs = platform_dev_attrs,
896    .match = platform_match,
897    .uevent = platform_uevent,
898    .pm = &platform_dev_pm_ops,
899};
900EXPORT_SYMBOL_GPL(platform_bus_type);
901
902int __init platform_bus_init(void)
903{
904    int error;
905
906    early_platform_cleanup();
907
908    error = device_register(&platform_bus);
909    if (error)
910        return error;
911    error = bus_register(&platform_bus_type);
912    if (error)
913        device_unregister(&platform_bus);
914    return error;
915}
916
917#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
918u64 dma_get_required_mask(struct device *dev)
919{
920    u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
921    u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
922    u64 mask;
923
924    if (!high_totalram) {
925        /* convert to mask just covering totalram */
926        low_totalram = (1 << (fls(low_totalram) - 1));
927        low_totalram += low_totalram - 1;
928        mask = low_totalram;
929    } else {
930        high_totalram = (1 << (fls(high_totalram) - 1));
931        high_totalram += high_totalram - 1;
932        mask = (((u64)high_totalram) << 32) + 0xffffffff;
933    }
934    return mask;
935}
936EXPORT_SYMBOL_GPL(dma_get_required_mask);
937#endif
938
939static __initdata LIST_HEAD(early_platform_driver_list);
940static __initdata LIST_HEAD(early_platform_device_list);
941
942/**
943 * early_platform_driver_register - register early platform driver
944 * @epdrv: early_platform driver structure
945 * @buf: string passed from early_param()
946 *
947 * Helper function for early_platform_init() / early_platform_init_buffer()
948 */
949int __init early_platform_driver_register(struct early_platform_driver *epdrv,
950                      char *buf)
951{
952    char *tmp;
953    int n;
954
955    /* Simply add the driver to the end of the global list.
956     * Drivers will by default be put on the list in compiled-in order.
957     */
958    if (!epdrv->list.next) {
959        INIT_LIST_HEAD(&epdrv->list);
960        list_add_tail(&epdrv->list, &early_platform_driver_list);
961    }
962
963    /* If the user has specified device then make sure the driver
964     * gets prioritized. The driver of the last device specified on
965     * command line will be put first on the list.
966     */
967    n = strlen(epdrv->pdrv->driver.name);
968    if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
969        list_move(&epdrv->list, &early_platform_driver_list);
970
971        /* Allow passing parameters after device name */
972        if (buf[n] == '\0' || buf[n] == ',')
973            epdrv->requested_id = -1;
974        else {
975            epdrv->requested_id = simple_strtoul(&buf[n + 1],
976                                 &tmp, 10);
977
978            if (buf[n] != '.' || (tmp == &buf[n + 1])) {
979                epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
980                n = 0;
981            } else
982                n += strcspn(&buf[n + 1], ",") + 1;
983        }
984
985        if (buf[n] == ',')
986            n++;
987
988        if (epdrv->bufsize) {
989            memcpy(epdrv->buffer, &buf[n],
990                   min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
991            epdrv->buffer[epdrv->bufsize - 1] = '\0';
992        }
993    }
994
995    return 0;
996}
997
998/**
999 * early_platform_add_devices - adds a number of early platform devices
1000 * @devs: array of early platform devices to add
1001 * @num: number of early platform devices in array
1002 *
1003 * Used by early architecture code to register early platform devices and
1004 * their platform data.
1005 */
1006void __init early_platform_add_devices(struct platform_device **devs, int num)
1007{
1008    struct device *dev;
1009    int i;
1010
1011    /* simply add the devices to list */
1012    for (i = 0; i < num; i++) {
1013        dev = &devs[i]->dev;
1014
1015        if (!dev->devres_head.next) {
1016            pm_runtime_early_init(dev);
1017            INIT_LIST_HEAD(&dev->devres_head);
1018            list_add_tail(&dev->devres_head,
1019                      &early_platform_device_list);
1020        }
1021    }
1022}
1023
1024/**
1025 * early_platform_driver_register_all - register early platform drivers
1026 * @class_str: string to identify early platform driver class
1027 *
1028 * Used by architecture code to register all early platform drivers
1029 * for a certain class. If omitted then only early platform drivers
1030 * with matching kernel command line class parameters will be registered.
1031 */
1032void __init early_platform_driver_register_all(char *class_str)
1033{
1034    /* The "class_str" parameter may or may not be present on the kernel
1035     * command line. If it is present then there may be more than one
1036     * matching parameter.
1037     *
1038     * Since we register our early platform drivers using early_param()
1039     * we need to make sure that they also get registered in the case
1040     * when the parameter is missing from the kernel command line.
1041     *
1042     * We use parse_early_options() to make sure the early_param() gets
1043     * called at least once. The early_param() may be called more than
1044     * once since the name of the preferred device may be specified on
1045     * the kernel command line. early_platform_driver_register() handles
1046     * this case for us.
1047     */
1048    parse_early_options(class_str);
1049}
1050
1051/**
1052 * early_platform_match - find early platform device matching driver
1053 * @epdrv: early platform driver structure
1054 * @id: id to match against
1055 */
1056static __init struct platform_device *
1057early_platform_match(struct early_platform_driver *epdrv, int id)
1058{
1059    struct platform_device *pd;
1060
1061    list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1062        if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1063            if (pd->id == id)
1064                return pd;
1065
1066    return NULL;
1067}
1068
1069/**
1070 * early_platform_left - check if early platform driver has matching devices
1071 * @epdrv: early platform driver structure
1072 * @id: return true if id or above exists
1073 */
1074static __init int early_platform_left(struct early_platform_driver *epdrv,
1075                       int id)
1076{
1077    struct platform_device *pd;
1078
1079    list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1080        if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1081            if (pd->id >= id)
1082                return 1;
1083
1084    return 0;
1085}
1086
1087/**
1088 * early_platform_driver_probe_id - probe drivers matching class_str and id
1089 * @class_str: string to identify early platform driver class
1090 * @id: id to match against
1091 * @nr_probe: number of platform devices to successfully probe before exiting
1092 */
1093static int __init early_platform_driver_probe_id(char *class_str,
1094                         int id,
1095                         int nr_probe)
1096{
1097    struct early_platform_driver *epdrv;
1098    struct platform_device *match;
1099    int match_id;
1100    int n = 0;
1101    int left = 0;
1102
1103    list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1104        /* only use drivers matching our class_str */
1105        if (strcmp(class_str, epdrv->class_str))
1106            continue;
1107
1108        if (id == -2) {
1109            match_id = epdrv->requested_id;
1110            left = 1;
1111
1112        } else {
1113            match_id = id;
1114            left += early_platform_left(epdrv, id);
1115
1116            /* skip requested id */
1117            switch (epdrv->requested_id) {
1118            case EARLY_PLATFORM_ID_ERROR:
1119            case EARLY_PLATFORM_ID_UNSET:
1120                break;
1121            default:
1122                if (epdrv->requested_id == id)
1123                    match_id = EARLY_PLATFORM_ID_UNSET;
1124            }
1125        }
1126
1127        switch (match_id) {
1128        case EARLY_PLATFORM_ID_ERROR:
1129            pr_warning("%s: unable to parse %s parameter\n",
1130                   class_str, epdrv->pdrv->driver.name);
1131            /* fall-through */
1132        case EARLY_PLATFORM_ID_UNSET:
1133            match = NULL;
1134            break;
1135        default:
1136            match = early_platform_match(epdrv, match_id);
1137        }
1138
1139        if (match) {
1140            /*
1141             * Set up a sensible init_name to enable
1142             * dev_name() and others to be used before the
1143             * rest of the driver core is initialized.
1144             */
1145            if (!match->dev.init_name && slab_is_available()) {
1146                if (match->id != -1)
1147                    match->dev.init_name =
1148                        kasprintf(GFP_KERNEL, "%s.%d",
1149                              match->name,
1150                              match->id);
1151                else
1152                    match->dev.init_name =
1153                        kasprintf(GFP_KERNEL, "%s",
1154                              match->name);
1155
1156                if (!match->dev.init_name)
1157                    return -ENOMEM;
1158            }
1159
1160            if (epdrv->pdrv->probe(match))
1161                pr_warning("%s: unable to probe %s early.\n",
1162                       class_str, match->name);
1163            else
1164                n++;
1165        }
1166
1167        if (n >= nr_probe)
1168            break;
1169    }
1170
1171    if (left)
1172        return n;
1173    else
1174        return -ENODEV;
1175}
1176
1177/**
1178 * early_platform_driver_probe - probe a class of registered drivers
1179 * @class_str: string to identify early platform driver class
1180 * @nr_probe: number of platform devices to successfully probe before exiting
1181 * @user_only: only probe user specified early platform devices
1182 *
1183 * Used by architecture code to probe registered early platform drivers
1184 * within a certain class. For probe to happen a registered early platform
1185 * device matching a registered early platform driver is needed.
1186 */
1187int __init early_platform_driver_probe(char *class_str,
1188                       int nr_probe,
1189                       int user_only)
1190{
1191    int k, n, i;
1192
1193    n = 0;
1194    for (i = -2; n < nr_probe; i++) {
1195        k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1196
1197        if (k < 0)
1198            break;
1199
1200        n += k;
1201
1202        if (user_only)
1203            break;
1204    }
1205
1206    return n;
1207}
1208
1209/**
1210 * early_platform_cleanup - clean up early platform code
1211 */
1212void __init early_platform_cleanup(void)
1213{
1214    struct platform_device *pd, *pd2;
1215
1216    /* clean up the devres list used to chain devices */
1217    list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1218                 dev.devres_head) {
1219        list_del(&pd->dev.devres_head);
1220        memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1221    }
1222}
1223
1224

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