125 lines
3 KiB
C
125 lines
3 KiB
C
|
/*
|
||
|
|
* Common code to handle map devices which are simple ROM
|
||
|
|
* (C) 2000 Red Hat. GPL'd.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <linux/types.h>
|
||
|
|
#include <linux/kernel.h>
|
||
|
|
#include <asm/io.h>
|
||
|
|
#include <asm/byteorder.h>
|
||
|
|
#include <linux/errno.h>
|
||
|
|
#include <linux/slab.h>
|
||
|
|
#include <linux/init.h>
|
||
|
|
#include <linux/of.h>
|
||
|
|
#include <linux/mtd/mtd.h>
|
||
|
|
#include <linux/mtd/map.h>
|
||
|
|
|
||
|
|
static int maprom_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
|
||
|
|
static int maprom_write (struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
|
||
|
|
static void maprom_nop (struct mtd_info *);
|
||
|
|
static struct mtd_info *map_rom_probe(struct map_info *map);
|
||
|
|
static int maprom_erase (struct mtd_info *mtd, struct erase_info *info);
|
||
|
|
static unsigned long maprom_unmapped_area(struct mtd_info *, unsigned long,
|
||
|
|
unsigned long, unsigned long);
|
||
|
|
|
||
|
|
static struct mtd_chip_driver maprom_chipdrv = {
|
||
|
|
.probe = map_rom_probe,
|
||
|
|
.name = "map_rom",
|
||
|
|
.module = THIS_MODULE
|
||
|
|
};
|
||
|
|
|
||
|
|
static unsigned int default_erasesize(struct map_info *map)
|
||
|
|
{
|
||
|
|
const __be32 *erase_size = NULL;
|
||
|
|
|
||
|
|
erase_size = of_get_property(map->device_node, "erase-size", NULL);
|
||
|
|
|
||
|
|
return !erase_size ? map->size : be32_to_cpu(*erase_size);
|
||
|
|
}
|
||
|
|
|
||
|
|
static struct mtd_info *map_rom_probe(struct map_info *map)
|
||
|
|
{
|
||
|
|
struct mtd_info *mtd;
|
||
|
|
|
||
|
|
mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
|
||
|
|
if (!mtd)
|
||
|
|
return NULL;
|
||
|
|
|
||
|
|
map->fldrv = &maprom_chipdrv;
|
||
|
|
mtd->priv = map;
|
||
|
|
mtd->name = map->name;
|
||
|
|
mtd->type = MTD_ROM;
|
||
|
|
mtd->size = map->size;
|
||
|
|
mtd->_get_unmapped_area = maprom_unmapped_area;
|
||
|
|
mtd->_read = maprom_read;
|
||
|
|
mtd->_write = maprom_write;
|
||
|
|
mtd->_sync = maprom_nop;
|
||
|
|
mtd->_erase = maprom_erase;
|
||
|
|
mtd->flags = MTD_CAP_ROM;
|
||
|
|
mtd->erasesize = default_erasesize(map);
|
||
|
|
mtd->writesize = 1;
|
||
|
|
mtd->writebufsize = 1;
|
||
|
|
|
||
|
|
__module_get(THIS_MODULE);
|
||
|
|
return mtd;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Allow NOMMU mmap() to directly map the device (if not NULL)
|
||
|
|
* - return the address to which the offset maps
|
||
|
|
* - return -ENOSYS to indicate refusal to do the mapping
|
||
|
|
*/
|
||
|
|
static unsigned long maprom_unmapped_area(struct mtd_info *mtd,
|
||
|
|
unsigned long len,
|
||
|
|
unsigned long offset,
|
||
|
|
unsigned long flags)
|
||
|
|
{
|
||
|
|
struct map_info *map = mtd->priv;
|
||
|
|
return (unsigned long) map->virt + offset;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int maprom_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
|
||
|
|
{
|
||
|
|
struct map_info *map = mtd->priv;
|
||
|
|
|
||
|
|
map_copy_from(map, buf, from, len);
|
||
|
|
*retlen = len;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void maprom_nop(struct mtd_info *mtd)
|
||
|
|
{
|
||
|
|
/* Nothing to see here */
|
||
|
|
}
|
||
|
|
|
||
|
|
static int maprom_write (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf)
|
||
|
|
{
|
||
|
|
return -EROFS;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int maprom_erase (struct mtd_info *mtd, struct erase_info *info)
|
||
|
|
{
|
||
|
|
/* We do our best 8) */
|
||
|
|
return -EROFS;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int __init map_rom_init(void)
|
||
|
|
{
|
||
|
|
register_mtd_chip_driver(&maprom_chipdrv);
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __exit map_rom_exit(void)
|
||
|
|
{
|
||
|
|
unregister_mtd_chip_driver(&maprom_chipdrv);
|
||
|
|
}
|
||
|
|
|
||
|
|
module_init(map_rom_init);
|
||
|
|
module_exit(map_rom_exit);
|
||
|
|
|
||
|
|
MODULE_LICENSE("GPL");
|
||
|
|
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
|
||
|
|
MODULE_DESCRIPTION("MTD chip driver for ROM chips");
|