blob: 47a43cf7e5c60fc162934b6da893b32dbd0cb717 [file] [log] [blame]
* 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/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 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 = map->size;
mtd->writesize = 1;
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)
return 0;
static void __exit map_rom_exit(void)
MODULE_AUTHOR("David Woodhouse <>");
MODULE_DESCRIPTION("MTD chip driver for ROM chips");