/*
 *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
 *			 <benh@kernel.crashing.org>
 *    and		 Arnd Bergmann, IBM Corp.
 *    Merged from powerpc/kernel/of_platform.c and
 *    sparc{,64}/kernel/of_device.c by Stephen Rothwell
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 *
 */
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/of_device.h>
#include <linux/of_platform.h>

extern struct device_attribute of_platform_device_attrs[];

static int of_platform_bus_match(struct device *dev, struct device_driver *drv)
{
	const struct of_device_id *matches = drv->of_match_table;

	if (!matches)
		return 0;

	return of_match_device(matches, dev) != NULL;
}

static int of_platform_device_probe(struct device *dev)
{
	int error = -ENODEV;
	struct of_platform_driver *drv;
	struct of_device *of_dev;
	const struct of_device_id *match;

	drv = to_of_platform_driver(dev->driver);
	of_dev = to_of_device(dev);

	if (!drv->probe)
		return error;

	of_dev_get(of_dev);

	match = of_match_device(drv->driver.of_match_table, dev);
	if (match)
		error = drv->probe(of_dev, match);
	if (error)
		of_dev_put(of_dev);

	return error;
}

static int of_platform_device_remove(struct device *dev)
{
	struct of_device *of_dev = to_of_device(dev);
	struct of_platform_driver *drv = to_of_platform_driver(dev->driver);

	if (dev->driver && drv->remove)
		drv->remove(of_dev);
	return 0;
}

static void of_platform_device_shutdown(struct device *dev)
{
	struct of_device *of_dev = to_of_device(dev);
	struct of_platform_driver *drv = to_of_platform_driver(dev->driver);

	if (dev->driver && drv->shutdown)
		drv->shutdown(of_dev);
}

#ifdef CONFIG_PM_SLEEP

static int of_platform_legacy_suspend(struct device *dev, pm_message_t mesg)
{
	struct of_device *of_dev = to_of_device(dev);
	struct of_platform_driver *drv = to_of_platform_driver(dev->driver);
	int ret = 0;

	if (dev->driver && drv->suspend)
		ret = drv->suspend(of_dev, mesg);
	return ret;
}

static int of_platform_legacy_resume(struct device *dev)
{
	struct of_device *of_dev = to_of_device(dev);
	struct of_platform_driver *drv = to_of_platform_driver(dev->driver);
	int ret = 0;

	if (dev->driver && drv->resume)
		ret = drv->resume(of_dev);
	return ret;
}

static int of_platform_pm_prepare(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (drv && drv->pm && drv->pm->prepare)
		ret = drv->pm->prepare(dev);

	return ret;
}

static void of_platform_pm_complete(struct device *dev)
{
	struct device_driver *drv = dev->driver;

	if (drv && drv->pm && drv->pm->complete)
		drv->pm->complete(dev);
}

#ifdef CONFIG_SUSPEND

static int of_platform_pm_suspend(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->suspend)
			ret = drv->pm->suspend(dev);
	} else {
		ret = of_platform_legacy_suspend(dev, PMSG_SUSPEND);
	}

	return ret;
}

static int of_platform_pm_suspend_noirq(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->suspend_noirq)
			ret = drv->pm->suspend_noirq(dev);
	}

	return ret;
}

static int of_platform_pm_resume(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->resume)
			ret = drv->pm->resume(dev);
	} else {
		ret = of_platform_legacy_resume(dev);
	}

	return ret;
}

static int of_platform_pm_resume_noirq(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->resume_noirq)
			ret = drv->pm->resume_noirq(dev);
	}

	return ret;
}

#else /* !CONFIG_SUSPEND */

#define of_platform_pm_suspend		NULL
#define of_platform_pm_resume		NULL
#define of_platform_pm_suspend_noirq	NULL
#define of_platform_pm_resume_noirq	NULL

#endif /* !CONFIG_SUSPEND */

#ifdef CONFIG_HIBERNATION

static int of_platform_pm_freeze(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->freeze)
			ret = drv->pm->freeze(dev);
	} else {
		ret = of_platform_legacy_suspend(dev, PMSG_FREEZE);
	}

	return ret;
}

static int of_platform_pm_freeze_noirq(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->freeze_noirq)
			ret = drv->pm->freeze_noirq(dev);
	}

	return ret;
}

static int of_platform_pm_thaw(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->thaw)
			ret = drv->pm->thaw(dev);
	} else {
		ret = of_platform_legacy_resume(dev);
	}

	return ret;
}

static int of_platform_pm_thaw_noirq(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->thaw_noirq)
			ret = drv->pm->thaw_noirq(dev);
	}

	return ret;
}

static int of_platform_pm_poweroff(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->poweroff)
			ret = drv->pm->poweroff(dev);
	} else {
		ret = of_platform_legacy_suspend(dev, PMSG_HIBERNATE);
	}

	return ret;
}

static int of_platform_pm_poweroff_noirq(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->poweroff_noirq)
			ret = drv->pm->poweroff_noirq(dev);
	}

	return ret;
}

static int of_platform_pm_restore(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->restore)
			ret = drv->pm->restore(dev);
	} else {
		ret = of_platform_legacy_resume(dev);
	}

	return ret;
}

static int of_platform_pm_restore_noirq(struct device *dev)
{
	struct device_driver *drv = dev->driver;
	int ret = 0;

	if (!drv)
		return 0;

	if (drv->pm) {
		if (drv->pm->restore_noirq)
			ret = drv->pm->restore_noirq(dev);
	}

	return ret;
}

#else /* !CONFIG_HIBERNATION */

#define of_platform_pm_freeze		NULL
#define of_platform_pm_thaw		NULL
#define of_platform_pm_poweroff		NULL
#define of_platform_pm_restore		NULL
#define of_platform_pm_freeze_noirq	NULL
#define of_platform_pm_thaw_noirq		NULL
#define of_platform_pm_poweroff_noirq	NULL
#define of_platform_pm_restore_noirq	NULL

#endif /* !CONFIG_HIBERNATION */

static struct dev_pm_ops of_platform_dev_pm_ops = {
	.prepare = of_platform_pm_prepare,
	.complete = of_platform_pm_complete,
	.suspend = of_platform_pm_suspend,
	.resume = of_platform_pm_resume,
	.freeze = of_platform_pm_freeze,
	.thaw = of_platform_pm_thaw,
	.poweroff = of_platform_pm_poweroff,
	.restore = of_platform_pm_restore,
	.suspend_noirq = of_platform_pm_suspend_noirq,
	.resume_noirq = of_platform_pm_resume_noirq,
	.freeze_noirq = of_platform_pm_freeze_noirq,
	.thaw_noirq = of_platform_pm_thaw_noirq,
	.poweroff_noirq = of_platform_pm_poweroff_noirq,
	.restore_noirq = of_platform_pm_restore_noirq,
};

#define OF_PLATFORM_PM_OPS_PTR	(&of_platform_dev_pm_ops)

#else /* !CONFIG_PM_SLEEP */

#define OF_PLATFORM_PM_OPS_PTR	NULL

#endif /* !CONFIG_PM_SLEEP */

int of_bus_type_init(struct bus_type *bus, const char *name)
{
	bus->name = name;
	bus->match = of_platform_bus_match;
	bus->probe = of_platform_device_probe;
	bus->remove = of_platform_device_remove;
	bus->shutdown = of_platform_device_shutdown;
	bus->dev_attrs = of_platform_device_attrs;
	bus->pm = OF_PLATFORM_PM_OPS_PTR;
	return bus_register(bus);
}

int of_register_driver(struct of_platform_driver *drv, struct bus_type *bus)
{
	drv->driver.bus = bus;

	/* register with core */
	return driver_register(&drv->driver);
}
EXPORT_SYMBOL(of_register_driver);

void of_unregister_driver(struct of_platform_driver *drv)
{
	driver_unregister(&drv->driver);
}
EXPORT_SYMBOL(of_unregister_driver);

#if !defined(CONFIG_SPARC)
/*
 * The following routines scan a subtree and registers a device for
 * each applicable node.
 *
 * Note: sparc doesn't use these routines because it has a different
 * mechanism for creating devices from device tree nodes.
 */

/**
 * of_platform_device_create - Alloc, initialize and register an of_device
 * @np: pointer to node to create device for
 * @bus_id: name to assign device
 * @parent: Linux device model parent device.
 */
struct of_device *of_platform_device_create(struct device_node *np,
					    const char *bus_id,
					    struct device *parent)
{
	struct of_device *dev;

	dev = of_device_alloc(np, bus_id, parent);
	if (!dev)
		return NULL;

	dev->archdata.dma_mask = 0xffffffffUL;
	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
	dev->dev.bus = &of_platform_bus_type;

	/* We do not fill the DMA ops for platform devices by default.
	 * This is currently the responsibility of the platform code
	 * to do such, possibly using a device notifier
	 */

	if (of_device_register(dev) != 0) {
		of_device_free(dev);
		return NULL;
	}

	return dev;
}
EXPORT_SYMBOL(of_platform_device_create);

/**
 * of_platform_bus_create - Create an OF device for a bus node and all its
 * children. Optionally recursively instantiate matching busses.
 * @bus: device node of the bus to instantiate
 * @matches: match table, NULL to use the default, OF_NO_DEEP_PROBE to
 * disallow recursive creation of child busses
 */
static int of_platform_bus_create(const struct device_node *bus,
				  const struct of_device_id *matches,
				  struct device *parent)
{
	struct device_node *child;
	struct of_device *dev;
	int rc = 0;

	for_each_child_of_node(bus, child) {
		pr_debug("   create child: %s\n", child->full_name);
		dev = of_platform_device_create(child, NULL, parent);
		if (dev == NULL)
			rc = -ENOMEM;
		else if (!of_match_node(matches, child))
			continue;
		if (rc == 0) {
			pr_debug("   and sub busses\n");
			rc = of_platform_bus_create(child, matches, &dev->dev);
		}
		if (rc) {
			of_node_put(child);
			break;
		}
	}
	return rc;
}

/**
 * of_platform_bus_probe - Probe the device-tree for platform busses
 * @root: parent of the first level to probe or NULL for the root of the tree
 * @matches: match table, NULL to use the default
 * @parent: parent to hook devices from, NULL for toplevel
 *
 * Note that children of the provided root are not instantiated as devices
 * unless the specified root itself matches the bus list and is not NULL.
 */
int of_platform_bus_probe(struct device_node *root,
			  const struct of_device_id *matches,
			  struct device *parent)
{
	struct device_node *child;
	struct of_device *dev;
	int rc = 0;

	if (matches == NULL)
		matches = of_default_bus_ids;
	if (matches == OF_NO_DEEP_PROBE)
		return -EINVAL;
	if (root == NULL)
		root = of_find_node_by_path("/");
	else
		of_node_get(root);

	pr_debug("of_platform_bus_probe()\n");
	pr_debug(" starting at: %s\n", root->full_name);

	/* Do a self check of bus type, if there's a match, create
	 * children
	 */
	if (of_match_node(matches, root)) {
		pr_debug(" root match, create all sub devices\n");
		dev = of_platform_device_create(root, NULL, parent);
		if (dev == NULL) {
			rc = -ENOMEM;
			goto bail;
		}
		pr_debug(" create all sub busses\n");
		rc = of_platform_bus_create(root, matches, &dev->dev);
		goto bail;
	}
	for_each_child_of_node(root, child) {
		if (!of_match_node(matches, child))
			continue;

		pr_debug("  match: %s\n", child->full_name);
		dev = of_platform_device_create(child, NULL, parent);
		if (dev == NULL)
			rc = -ENOMEM;
		else
			rc = of_platform_bus_create(child, matches, &dev->dev);
		if (rc) {
			of_node_put(child);
			break;
		}
	}
 bail:
	of_node_put(root);
	return rc;
}
EXPORT_SYMBOL(of_platform_bus_probe);
#endif /* !CONFIG_SPARC */