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 23 static struct mtd_chip_driver maprom_chipdrv = { 24 .probe = map_rom_probe, 25 .name = "map_rom", 26 .module = THIS_MODULE 27 }; 28 29 static struct mtd_info *map_rom_probe(struct map_info *map) 30 { 31 struct mtd_info *mtd; 32 33 mtd = kzalloc(sizeof(*mtd), GFP_KERNEL); 34 if (!mtd) 35 return NULL; 36 37 map->fldrv = &maprom_chipdrv; 38 mtd->priv = map; 39 mtd->name = map->name; 40 mtd->type = MTD_ROM; 41 mtd->size = map->size; 42 mtd->read = maprom_read; 43 mtd->write = maprom_write; 44 mtd->sync = maprom_nop; 45 mtd->flags = MTD_CAP_ROM; 46 mtd->erasesize = map->size; 47 mtd->writesize = 1; 48 49 __module_get(THIS_MODULE); 50 return mtd; 51 } 52 53 54 static int maprom_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf) 55 { 56 struct map_info *map = mtd->priv; 57 58 map_copy_from(map, buf, from, len); 59 *retlen = len; 60 return 0; 61 } 62 63 static void maprom_nop(struct mtd_info *mtd) 64 { 65 /* Nothing to see here */ 66 } 67 68 static int maprom_write (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf) 69 { 70 printk(KERN_NOTICE "maprom_write called\n"); 71 return -EIO; 72 } 73 74 static int __init map_rom_init(void) 75 { 76 register_mtd_chip_driver(&maprom_chipdrv); 77 return 0; 78 } 79 80 static void __exit map_rom_exit(void) 81 { 82 unregister_mtd_chip_driver(&maprom_chipdrv); 83 } 84 85 module_init(map_rom_init); 86 module_exit(map_rom_exit); 87 88 MODULE_LICENSE("GPL"); 89 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); 90 MODULE_DESCRIPTION("MTD chip driver for ROM chips"); 91