drivers/mtd/nand/sm_common.h

   1 /*
   2  * Copyright © 2009 - Maxim Levitsky
   3  * Common routines & support for SmartMedia/xD format
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9 #include <linux/bitops.h>
  10 #include <linux/mtd/mtd.h>
  11
  12 /* Full oob structure as written on the flash */
  13 struct sm_oob {
  14         uint32_t reserved;
  15         uint8_t data_status;
  16         uint8_t block_status;
  17         uint8_t lba_copy1[2];
  18         uint8_t ecc2[3];
  19         uint8_t lba_copy2[2];
  20         uint8_t ecc1[3];
  21 } __packed;
  22
  23
  24 /* one sector is always 512 bytes, but it can consist of two nand pages */
  25 #define SM_SECTOR_SIZE          512
  26
  27 /* oob area is also 16 bytes, but might be from two pages */
  28 #define SM_OOB_SIZE             16
  29
  30 /* This is maximum zone size, and all devices that have more that one zone
  31    have this size */
  32 #define SM_MAX_ZONE_SIZE        1024
  33
  34 /* support for small page nand */
  35 #define SM_SMALL_PAGE           256
  36 #define SM_SMALL_OOB_SIZE       8
  37
  38
  39 extern int sm_register_device(struct mtd_info *mtd, int smartmedia);
  40
  41
  42 static inline int sm_sector_valid(struct sm_oob *oob)
  43 {
  44         return hweight16(oob->data_status) >= 5;
  45 }
  46
  47 static inline int sm_block_valid(struct sm_oob *oob)
  48 {
  49         return hweight16(oob->block_status) >= 7;
  50 }
  51
  52 static inline int sm_block_erased(struct sm_oob *oob)
  53 {
  54         static const uint32_t erased_pattern[4] = {
  55                 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
  56
  57         /* First test for erased block */
  58         if (!memcmp(oob, erased_pattern, sizeof(*oob)))
  59                 return 1;
  60         return 0;
  61 }