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 1.23 2005/01/05 18:05:12 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/slab.h> 14 #include <linux/init.h> 15 #include <linux/mtd/mtd.h> 16 #include <linux/mtd/map.h> 17 #include <linux/mtd/compatmac.h> 18 19 static int maprom_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *); 20 static int maprom_write (struct mtd_info *, loff_t, size_t, size_t *, const u_char *); 21 static void maprom_nop (struct mtd_info *); 22 static struct mtd_info *map_rom_probe(struct map_info *map); 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 = kmalloc(sizeof(*mtd), GFP_KERNEL); 35 if (!mtd) 36 return NULL; 37 38 memset(mtd, 0, sizeof(*mtd)); 39 40 map->fldrv = &maprom_chipdrv; 41 mtd->priv = map; 42 mtd->name = map->name; 43 mtd->type = MTD_ROM; 44 mtd->size = map->size; 45 mtd->read = maprom_read; 46 mtd->write = maprom_write; 47 mtd->sync = maprom_nop; 48 mtd->flags = MTD_CAP_ROM; 49 mtd->erasesize = 131072; 50 while(mtd->size & (mtd->erasesize - 1)) 51 mtd->erasesize >>= 1; 52 53 __module_get(THIS_MODULE); 54 return mtd; 55 } 56 57 58 static int maprom_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf) 59 { 60 struct map_info *map = mtd->priv; 61 62 map_copy_from(map, buf, from, len); 63 *retlen = len; 64 return 0; 65 } 66 67 static void maprom_nop(struct mtd_info *mtd) 68 { 69 /* Nothing to see here */ 70 } 71 72 static int maprom_write (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf) 73 { 74 printk(KERN_NOTICE "maprom_write called\n"); 75 return -EIO; 76 } 77 78 static int __init map_rom_init(void) 79 { 80 register_mtd_chip_driver(&maprom_chipdrv); 81 return 0; 82 } 83 84 static void __exit map_rom_exit(void) 85 { 86 unregister_mtd_chip_driver(&maprom_chipdrv); 87 } 88 89 module_init(map_rom_init); 90 module_exit(map_rom_exit); 91 92 MODULE_LICENSE("GPL"); 93 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); 94 MODULE_DESCRIPTION("MTD chip driver for ROM chips"); 95