int nand_read_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,
u_char *buffer);
int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,
int nand_read_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,
u_char *buffer);
int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,