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Diffstat (limited to 'drivers/nand/nand_ecc.c')
-rw-r--r--drivers/nand/nand_ecc.c45
1 files changed, 22 insertions, 23 deletions
diff --git a/drivers/nand/nand_ecc.c b/drivers/nand/nand_ecc.c
index dc9db4b..6e11c22 100644
--- a/drivers/nand/nand_ecc.c
+++ b/drivers/nand/nand_ecc.c
@@ -13,16 +13,16 @@
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 or (at your option) any
* later version.
- *
+ *
* This file is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
- *
+ *
* You should have received a copy of the GNU General Public License along
* with this file; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
- *
+ *
* As a special exception, if other files instantiate templates or use
* macros or inline functions from these files, or you compile these
* files and link them with other works to produce a work based on these
@@ -30,7 +30,7 @@
* covered by the GNU General Public License. However the source code for
* these files must still be made available in accordance with section (3)
* of the GNU General Public License.
- *
+ *
* This exception does not invalidate any other reasons why a work based on
* this file might be covered by the GNU General Public License.
*/
@@ -66,7 +66,7 @@ static const u_char nand_ecc_precalc_table[] = {
* nand_trans_result - [GENERIC] create non-inverted ECC
* @reg2: line parity reg 2
* @reg3: line parity reg 3
- * @ecc_code: ecc
+ * @ecc_code: ecc
*
* Creates non-inverted ECC code from line parity
*/
@@ -74,11 +74,11 @@ static void nand_trans_result(u_char reg2, u_char reg3,
u_char *ecc_code)
{
u_char a, b, i, tmp1, tmp2;
-
+
/* Initialize variables */
a = b = 0x80;
tmp1 = tmp2 = 0;
-
+
/* Calculate first ECC byte */
for (i = 0; i < 4; i++) {
if (reg3 & a) /* LP15,13,11,9 --> ecc_code[0] */
@@ -89,7 +89,7 @@ static void nand_trans_result(u_char reg2, u_char reg3,
b >>= 1;
a >>= 1;
}
-
+
/* Calculate second ECC byte */
b = 0x80;
for (i = 0; i < 4; i++) {
@@ -101,7 +101,7 @@ static void nand_trans_result(u_char reg2, u_char reg3,
b >>= 1;
a >>= 1;
}
-
+
/* Store two of the ECC bytes */
ecc_code[0] = tmp1;
ecc_code[1] = tmp2;
@@ -117,28 +117,28 @@ int nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code
{
u_char idx, reg1, reg2, reg3;
int j;
-
+
/* Initialize variables */
reg1 = reg2 = reg3 = 0;
ecc_code[0] = ecc_code[1] = ecc_code[2] = 0;
-
- /* Build up column parity */
+
+ /* Build up column parity */
for(j = 0; j < 256; j++) {
-
+
/* Get CP0 - CP5 from table */
idx = nand_ecc_precalc_table[dat[j]];
reg1 ^= (idx & 0x3f);
-
+
/* All bit XOR = 1 ? */
if (idx & 0x40) {
reg3 ^= (u_char) j;
reg2 ^= ~((u_char) j);
}
}
-
+
/* Create non-inverted ECC code from line parity */
nand_trans_result(reg2, reg3, ecc_code);
-
+
/* Calculate final ECC code */
ecc_code[0] = ~ecc_code[0];
ecc_code[1] = ~ecc_code[1];
@@ -158,12 +158,12 @@ int nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code
int nand_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc, u_char *calc_ecc)
{
u_char a, b, c, d1, d2, d3, add, bit, i;
-
- /* Do error detection */
+
+ /* Do error detection */
d1 = calc_ecc[0] ^ read_ecc[0];
d2 = calc_ecc[1] ^ read_ecc[1];
d3 = calc_ecc[2] ^ read_ecc[2];
-
+
if ((d1 | d2 | d3) == 0) {
/* No errors */
return 0;
@@ -172,7 +172,7 @@ int nand_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc, u_cha
a = (d1 ^ (d1 >> 1)) & 0x55;
b = (d2 ^ (d2 >> 1)) & 0x55;
c = (d3 ^ (d3 >> 1)) & 0x54;
-
+
/* Found and will correct single bit error in the data */
if ((a == 0x55) && (b == 0x55) && (c == 0x54)) {
c = 0x80;
@@ -205,8 +205,7 @@ int nand_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc, u_cha
a ^= (b << bit);
dat[add] = a;
return 1;
- }
- else {
+ } else {
i = 0;
while (d1) {
if (d1 & 0x01)
@@ -236,7 +235,7 @@ int nand_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc, u_cha
}
}
}
-
+
/* Should never happen */
return -1;
}