1 /* 2 * Common code to handle map devices which are simple ROM 3 * (C) 2000 Red Hat. GPL'd. 4 */ 5 6 #include <linux/module.h> 7 #include <linux/types.h> 8 #include <linux/kernel.h> 9 #include <asm/io.h> 10 #include <asm/byteorder.h> 11 #include <linux/errno.h> 12 #include <linux/slab.h> 13 #include <linux/init.h> 14 #include <linux/mtd/mtd.h> 15 #include <linux/mtd/map.h> 16 #include <linux/mtd/compatmac.h> 17 18 static int maprom_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *); 19 static int maprom_write (struct mtd_info *, loff_t, size_t, size_t *, const u_char *); 20 static void maprom_nop (struct mtd_info *); 21 static struct mtd_info *map_rom_probe(struct map_info *map); 22 static int maprom_erase (struct mtd_info *mtd, struct erase_info *info); 23 24 static struct mtd_chip_driver maprom_chipdrv = { 25 .probe = map_rom_probe, 26 .name = "map_rom", 27 .module = THIS_MODULE 28 }; 29 30 static struct mtd_info *map_rom_probe(struct map_info *map) 31 { 32 struct mtd_info *mtd; 33 34 mtd = kzalloc(sizeof(*mtd), GFP_KERNEL); 35 if (!mtd) 36 return NULL; 37 38 map->fldrv = &maprom_chipdrv; 39 mtd->priv = map; 40 mtd->name = map->name; 41 mtd->type = MTD_ROM; 42 mtd->size = map->size; 43 mtd->read = maprom_read; 44 mtd->write = maprom_write; 45 mtd->sync = maprom_nop; 46 mtd->erase = maprom_erase; 47 mtd->flags = MTD_CAP_ROM; 48 mtd->erasesize = map->size; 49 mtd->writesize = 1; 50 51 __module_get(THIS_MODULE); 52 return mtd; 53 } 54 55 56 static int maprom_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf) 57 { 58 struct map_info *map = mtd->priv; 59 60 map_copy_from(map, buf, from, len); 61 *retlen = len; 62 return 0; 63 } 64 65 static void maprom_nop(struct mtd_info *mtd) 66 { 67 /* Nothing to see here */ 68 } 69 70 static int maprom_write (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf) 71 { 72 printk(KERN_NOTICE "maprom_write called\n"); 73 return -EIO; 74 } 75 76 static int maprom_erase (struct mtd_info *mtd, struct erase_info *info) 77 { 78 /* We do our best 8) */ 79 return -EROFS; 80 } 81 82 static int __init map_rom_init(void) 83 { 84 register_mtd_chip_driver(&maprom_chipdrv); 85 return 0; 86 } 87 88 static void __exit map_rom_exit(void) 89 { 90 unregister_mtd_chip_driver(&maprom_chipdrv); 91 } 92 93 module_init(map_rom_init); 94 module_exit(map_rom_exit); 95 96 MODULE_LICENSE("GPL"); 97 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); 98 MODULE_DESCRIPTION("MTD chip driver for ROM chips"); 99