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/*
* $Id: chipreg.c,v 1.17 2004/11/16 18:29:00 dwmw2 Exp $
*
* Registration for chip drivers
*
*/
#include <linux/kernel.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>
static DEFINE_SPINLOCK(chip_drvs_lock);
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");
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