/* * $Id: chipreg.c,v 1.2 2007/09/21 03:09:24 quy Exp $ * * Registration for chip drivers * */#include <linux/kernel.h>#include <linux/config.h>#include <linux/module.h>#include <linux/kmod.h>#include <linux/spinlock.h>#include <linux/slab.h>#include <linux/mtd/map.h>#include <linux/mtd/mtd.h>#include <linux/mtd/compatmac.h>spinlock_t chip_drvs_lock = SPIN_LOCK_UNLOCKED;static LIST_HEAD(chip_drvs_list);void register_mtd_chip_driver(struct mtd_chip_driver *drv){	spin_lock(&chip_drvs_lock);	list_add(&drv->list, &chip_drvs_list);	spin_unlock(&chip_drvs_lock);}void unregister_mtd_chip_driver(struct mtd_chip_driver *drv){	spin_lock(&chip_drvs_lock);	list_del(&drv->list);	spin_unlock(&chip_drvs_lock);}static struct mtd_chip_driver *get_mtd_chip_driver (const char *name){	struct list_head *pos;	struct mtd_chip_driver *ret = NULL, *this;	spin_lock(&chip_drvs_lock);	list_for_each(pos, &chip_drvs_list) {		this = list_entry(pos, typeof(*this), list);				if (!strcmp(this->name, name)) {			ret = this;			break;		}	}	if (ret && !try_module_get(ret->module))		ret = NULL;	spin_unlock(&chip_drvs_lock);	return ret;}	/* Hide all the horrid details, like some silly person taking	   get_module_symbol() away from us, from the caller. */struct mtd_info *do_map_probe(const char *name, struct map_info *map){	struct mtd_chip_driver *drv;	struct mtd_info *ret;	drv = get_mtd_chip_driver(name);	if (!drv && !request_module("%s", name))		drv = get_mtd_chip_driver(name);	if (!drv)		return NULL;	ret = drv->probe(map);	/* We decrease the use count here. It may have been a 	   probe-only module, which is no longer required from this	   point, having given us a handle on (and increased the use	   count of) the actual driver code.	*/	module_put(drv->module);	if (ret)		return ret;		return NULL;}/* * Destroy an MTD device which was created for a map device. * Make sure the MTD device is already unregistered before calling this */void map_destroy(struct mtd_info *mtd){	struct map_info *map = mtd->priv;	if (map->fldrv->destroy)		map->fldrv->destroy(mtd);	module_put(map->fldrv->module);	kfree(mtd);}EXPORT_SYMBOL(register_mtd_chip_driver);EXPORT_SYMBOL(unregister_mtd_chip_driver);EXPORT_SYMBOL(do_map_probe);EXPORT_SYMBOL(map_destroy);MODULE_LICENSE("GPL");MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");MODULE_DESCRIPTION("Core routines for registering and invoking MTD chip drivers");