u-boot/drivers/mtd/mtdcore.c
Wolfgang Denk d4c8aa9cb4 Coding Style cleanup: remove trailing empty lines
Signed-off-by: Wolfgang Denk <wd@denx.de>
2013-10-14 16:06:54 -04:00

390 lines
9.6 KiB
C

/*
* Core registration and callback routines for MTD
* drivers and users.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/mtd/mtd.h>
#include <linux/compat.h>
#include <ubi_uboot.h>
struct mtd_info *mtd_table[MAX_MTD_DEVICES];
int add_mtd_device(struct mtd_info *mtd)
{
int i;
BUG_ON(mtd->writesize == 0);
for (i = 0; i < MAX_MTD_DEVICES; i++)
if (!mtd_table[i]) {
mtd_table[i] = mtd;
mtd->index = i;
mtd->usecount = 0;
/* default value if not set by driver */
if (mtd->bitflip_threshold == 0)
mtd->bitflip_threshold = mtd->ecc_strength;
/* No need to get a refcount on the module containing
the notifier, since we hold the mtd_table_mutex */
/* We _know_ we aren't being removed, because
our caller is still holding us here. So none
of this try_ nonsense, and no bitching about it
either. :) */
return 0;
}
return 1;
}
/**
* del_mtd_device - unregister an MTD device
* @mtd: pointer to MTD device info structure
*
* Remove a device from the list of MTD devices present in the system,
* and notify each currently active MTD 'user' of its departure.
* Returns zero on success or 1 on failure, which currently will happen
* if the requested device does not appear to be present in the list.
*/
int del_mtd_device(struct mtd_info *mtd)
{
int ret;
if (mtd_table[mtd->index] != mtd) {
ret = -ENODEV;
} else if (mtd->usecount) {
printk(KERN_NOTICE "Removing MTD device #%d (%s)"
" with use count %d\n",
mtd->index, mtd->name, mtd->usecount);
ret = -EBUSY;
} else {
/* No need to get a refcount on the module containing
* the notifier, since we hold the mtd_table_mutex */
mtd_table[mtd->index] = NULL;
ret = 0;
}
return ret;
}
/**
* get_mtd_device - obtain a validated handle for an MTD device
* @mtd: last known address of the required MTD device
* @num: internal device number of the required MTD device
*
* Given a number and NULL address, return the num'th entry in the device
* table, if any. Given an address and num == -1, search the device table
* for a device with that address and return if it's still present. Given
* both, return the num'th driver only if its address matches. Return
* error code if not.
*/
struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
{
struct mtd_info *ret = NULL;
int i, err = -ENODEV;
if (num == -1) {
for (i = 0; i < MAX_MTD_DEVICES; i++)
if (mtd_table[i] == mtd)
ret = mtd_table[i];
} else if (num < MAX_MTD_DEVICES) {
ret = mtd_table[num];
if (mtd && mtd != ret)
ret = NULL;
}
if (!ret)
goto out_unlock;
ret->usecount++;
return ret;
out_unlock:
return ERR_PTR(err);
}
/**
* get_mtd_device_nm - obtain a validated handle for an MTD device by
* device name
* @name: MTD device name to open
*
* This function returns MTD device description structure in case of
* success and an error code in case of failure.
*/
struct mtd_info *get_mtd_device_nm(const char *name)
{
int i, err = -ENODEV;
struct mtd_info *mtd = NULL;
for (i = 0; i < MAX_MTD_DEVICES; i++) {
if (mtd_table[i] && !strcmp(name, mtd_table[i]->name)) {
mtd = mtd_table[i];
break;
}
}
if (!mtd)
goto out_unlock;
mtd->usecount++;
return mtd;
out_unlock:
return ERR_PTR(err);
}
void put_mtd_device(struct mtd_info *mtd)
{
int c;
c = --mtd->usecount;
BUG_ON(c < 0);
}
#if defined(CONFIG_CMD_MTDPARTS_SPREAD)
/**
* mtd_get_len_incl_bad
*
* Check if length including bad blocks fits into device.
*
* @param mtd an MTD device
* @param offset offset in flash
* @param length image length
* @return image length including bad blocks in *len_incl_bad and whether or not
* the length returned was truncated in *truncated
*/
void mtd_get_len_incl_bad(struct mtd_info *mtd, uint64_t offset,
const uint64_t length, uint64_t *len_incl_bad,
int *truncated)
{
*truncated = 0;
*len_incl_bad = 0;
if (!mtd->block_isbad) {
*len_incl_bad = length;
return;
}
uint64_t len_excl_bad = 0;
uint64_t block_len;
while (len_excl_bad < length) {
if (offset >= mtd->size) {
*truncated = 1;
return;
}
block_len = mtd->erasesize - (offset & (mtd->erasesize - 1));
if (!mtd->block_isbad(mtd, offset & ~(mtd->erasesize - 1)))
len_excl_bad += block_len;
*len_incl_bad += block_len;
offset += block_len;
}
}
#endif /* defined(CONFIG_CMD_MTDPARTS_SPREAD) */
/*
* Erase is an asynchronous operation. Device drivers are supposed
* to call instr->callback() whenever the operation completes, even
* if it completes with a failure.
* Callers are supposed to pass a callback function and wait for it
* to be called before writing to the block.
*/
int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
{
if (instr->addr > mtd->size || instr->len > mtd->size - instr->addr)
return -EINVAL;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
if (!instr->len) {
instr->state = MTD_ERASE_DONE;
mtd_erase_callback(instr);
return 0;
}
return mtd->_erase(mtd, instr);
}
int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
u_char *buf)
{
int ret_code;
if (from < 0 || from > mtd->size || len > mtd->size - from)
return -EINVAL;
if (!len)
return 0;
/*
* In the absence of an error, drivers return a non-negative integer
* representing the maximum number of bitflips that were corrected on
* any one ecc region (if applicable; zero otherwise).
*/
ret_code = mtd->_read(mtd, from, len, retlen, buf);
if (unlikely(ret_code < 0))
return ret_code;
if (mtd->ecc_strength == 0)
return 0; /* device lacks ecc */
return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
}
int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
const u_char *buf)
{
*retlen = 0;
if (to < 0 || to > mtd->size || len > mtd->size - to)
return -EINVAL;
if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (!len)
return 0;
return mtd->_write(mtd, to, len, retlen, buf);
}
/*
* In blackbox flight recorder like scenarios we want to make successful writes
* in interrupt context. panic_write() is only intended to be called when its
* known the kernel is about to panic and we need the write to succeed. Since
* the kernel is not going to be running for much longer, this function can
* break locks and delay to ensure the write succeeds (but not sleep).
*/
int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
const u_char *buf)
{
*retlen = 0;
if (!mtd->_panic_write)
return -EOPNOTSUPP;
if (to < 0 || to > mtd->size || len > mtd->size - to)
return -EINVAL;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (!len)
return 0;
return mtd->_panic_write(mtd, to, len, retlen, buf);
}
int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
{
ops->retlen = ops->oobretlen = 0;
if (!mtd->_read_oob)
return -EOPNOTSUPP;
return mtd->_read_oob(mtd, from, ops);
}
/*
* Method to access the protection register area, present in some flash
* devices. The user data is one time programmable but the factory data is read
* only.
*/
int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
size_t len)
{
if (!mtd->_get_fact_prot_info)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_get_fact_prot_info(mtd, buf, len);
}
int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
*retlen = 0;
if (!mtd->_read_fact_prot_reg)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_read_fact_prot_reg(mtd, from, len, retlen, buf);
}
int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
size_t len)
{
if (!mtd->_get_user_prot_info)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_get_user_prot_info(mtd, buf, len);
}
int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
*retlen = 0;
if (!mtd->_read_user_prot_reg)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_read_user_prot_reg(mtd, from, len, retlen, buf);
}
int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, u_char *buf)
{
*retlen = 0;
if (!mtd->_write_user_prot_reg)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_write_user_prot_reg(mtd, to, len, retlen, buf);
}
int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len)
{
if (!mtd->_lock_user_prot_reg)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_lock_user_prot_reg(mtd, from, len);
}
/* Chip-supported device locking */
int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
if (!mtd->_lock)
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
return -EINVAL;
if (!len)
return 0;
return mtd->_lock(mtd, ofs, len);
}
int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
if (!mtd->_unlock)
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
return -EINVAL;
if (!len)
return 0;
return mtd->_unlock(mtd, ofs, len);
}
int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
{
if (!mtd->_block_isbad)
return 0;
if (ofs < 0 || ofs > mtd->size)
return -EINVAL;
return mtd->_block_isbad(mtd, ofs);
}
int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
{
if (!mtd->_block_markbad)
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size)
return -EINVAL;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
return mtd->_block_markbad(mtd, ofs);
}