ia64/linux-2.6.18-xen.hg

view drivers/mtd/chips/chipreg.c @ 912:dd42cdb0ab89

[IA64] Build blktap2 driver by default in x86 builds.

add CONFIG_XEN_BLKDEV_TAP2=y to buildconfigs/linux-defconfig_xen_ia64.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Mon Jun 29 12:09:16 2009 +0900 (2009-06-29)
parents 831230e53067
children
line source
1 /*
2 * $Id: chipreg.c,v 1.17 2004/11/16 18:29:00 dwmw2 Exp $
3 *
4 * Registration for chip drivers
5 *
6 */
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/kmod.h>
11 #include <linux/spinlock.h>
12 #include <linux/slab.h>
13 #include <linux/mtd/map.h>
14 #include <linux/mtd/mtd.h>
15 #include <linux/mtd/compatmac.h>
17 static DEFINE_SPINLOCK(chip_drvs_lock);
18 static LIST_HEAD(chip_drvs_list);
20 void register_mtd_chip_driver(struct mtd_chip_driver *drv)
21 {
22 spin_lock(&chip_drvs_lock);
23 list_add(&drv->list, &chip_drvs_list);
24 spin_unlock(&chip_drvs_lock);
25 }
27 void unregister_mtd_chip_driver(struct mtd_chip_driver *drv)
28 {
29 spin_lock(&chip_drvs_lock);
30 list_del(&drv->list);
31 spin_unlock(&chip_drvs_lock);
32 }
34 static struct mtd_chip_driver *get_mtd_chip_driver (const char *name)
35 {
36 struct list_head *pos;
37 struct mtd_chip_driver *ret = NULL, *this;
39 spin_lock(&chip_drvs_lock);
41 list_for_each(pos, &chip_drvs_list) {
42 this = list_entry(pos, typeof(*this), list);
44 if (!strcmp(this->name, name)) {
45 ret = this;
46 break;
47 }
48 }
49 if (ret && !try_module_get(ret->module))
50 ret = NULL;
52 spin_unlock(&chip_drvs_lock);
54 return ret;
55 }
57 /* Hide all the horrid details, like some silly person taking
58 get_module_symbol() away from us, from the caller. */
60 struct mtd_info *do_map_probe(const char *name, struct map_info *map)
61 {
62 struct mtd_chip_driver *drv;
63 struct mtd_info *ret;
65 drv = get_mtd_chip_driver(name);
67 if (!drv && !request_module("%s", name))
68 drv = get_mtd_chip_driver(name);
70 if (!drv)
71 return NULL;
73 ret = drv->probe(map);
75 /* We decrease the use count here. It may have been a
76 probe-only module, which is no longer required from this
77 point, having given us a handle on (and increased the use
78 count of) the actual driver code.
79 */
80 module_put(drv->module);
82 if (ret)
83 return ret;
85 return NULL;
86 }
87 /*
88 * Destroy an MTD device which was created for a map device.
89 * Make sure the MTD device is already unregistered before calling this
90 */
91 void map_destroy(struct mtd_info *mtd)
92 {
93 struct map_info *map = mtd->priv;
95 if (map->fldrv->destroy)
96 map->fldrv->destroy(mtd);
98 module_put(map->fldrv->module);
100 kfree(mtd);
101 }
103 EXPORT_SYMBOL(register_mtd_chip_driver);
104 EXPORT_SYMBOL(unregister_mtd_chip_driver);
105 EXPORT_SYMBOL(do_map_probe);
106 EXPORT_SYMBOL(map_destroy);
108 MODULE_LICENSE("GPL");
109 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
110 MODULE_DESCRIPTION("Core routines for registering and invoking MTD chip drivers");