drivers/mtd/map_rom.c

   1 /*
   2  * Common code to handle map devices which are simple ROM
   3  * (C) 2000 Red Hat. GPL'd.
   4  * $Id: map_rom.c,v 1.10 2000/12/10 01:39:13 dwmw2 Exp $
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/types.h>
   9 #include <linux/kernel.h>
  10 #include <asm/io.h>
  11 #include <asm/byteorder.h>
  12 #include <linux/errno.h>
  13 #include <linux/malloc.h>
  14
  15 #include <linux/mtd/map.h>
  16
  17 static int maprom_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
  18 static int maprom_write (struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
  19 static void maprom_nop (struct mtd_info *);
  20
  21 static const char im_name[] = "map_rom_probe";
  22
  23 /* This routine is made available to other mtd code via
  24  * inter_module_register.  It must only be accessed through
  25  * inter_module_get which will bump the use count of this module.  The
  26  * addresses passed back in mtd are valid as long as the use count of
  27  * this module is non-zero, i.e. between inter_module_get and
  28  * inter_module_put.  Keith Owens <kaos@ocs.com.au> 29 Oct 2000.
  29  */
  30
  31 struct mtd_info *map_rom_probe(struct map_info *map)
  32 {
  33         struct mtd_info *mtd;
  34
  35         mtd = kmalloc(sizeof(*mtd), GFP_KERNEL);
  36         if (!mtd)
  37                 return NULL;
  38
  39         memset(mtd, 0, sizeof(*mtd));
  40
  41         map->im_name = im_name;
  42         map->fldrv_destroy = maprom_nop;
  43         mtd->priv = map;
  44         mtd->name = map->name;
  45         mtd->type = MTD_ROM;
  46         mtd->size = map->size;
  47         mtd->read = maprom_read;
  48         mtd->write = maprom_write;
  49         mtd->sync = maprom_nop;
  50         mtd->flags = MTD_CAP_ROM;
  51         mtd->erasesize = 131072;
  52
  53         return mtd;
  54 }
  55
  56
  57 static int maprom_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
  58 {
  59         struct map_info *map = (struct map_info *)mtd->priv;
  60
  61         map->copy_from(map, buf, from, len);
  62         *retlen = len;
  63         return 0;
  64 }
  65
  66 static void maprom_nop(struct mtd_info *mtd)
  67 {
  68         /* Nothing to see here */
  69 }
  70
  71 static int maprom_write (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf)
  72 {
  73         printk(KERN_NOTICE "maprom_write called\n");
  74         return -EIO;
  75 }
  76
  77 #if LINUX_VERSION_CODE < 0x20212 && defined(MODULE)
  78 #define map_rom_init init_module
  79 #define map_rom_exit cleanup_module
  80 #endif
  81
  82 static int __init map_rom_init(void)
  83 {
  84         inter_module_register(im_name, THIS_MODULE, &map_rom_probe);
  85         return 0;
  86 }
  87
  88 static void __exit map_rom_exit(void)
  89 {
  90         inter_module_unregister(im_name);
  91 }
  92
  93 module_init(map_rom_init);
  94 module_exit(map_rom_exit);