[MTD] DOC: Fixup read functions and do a little cleanup

The NAND rework resulted in non ECC based reads. Fix it up and
do a bit of cleanup while at it.

Pointed out by Adrian Bunk.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 63 insertions, 101 deletions

diff --git a/drivers/mtd/devices/doc2001plus.c b/drivers/mtd/devices/doc2001plus.c
index 66cb1e50469a..92dbb47f2ac3 100644
--- a/drivers/mtd/devices/doc2001plus.c
+++ b/drivers/mtd/devices/doc2001plus.c
@@ -41,12 +41,6 @@ static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
                 size_t *retlen, u_char *buf);
 static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
                 size_t *retlen, const u_char *buf);
-static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
-                size_t *retlen, u_char *buf, u_char *eccbuf,
-                struct nand_oobinfo *oobsel);
-static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
-                size_t *retlen, const u_char *buf, u_char *eccbuf,
-                struct nand_oobinfo *oobsel);
 static int doc_read_oob(struct mtd_info *mtd, loff_t ofs,
                         struct mtd_oob_ops *ops);
 static int doc_write_oob(struct mtd_info *mtd, loff_t ofs,
@@ -595,18 +589,10 @@ static int doc_dumpblk(struct mtd_info *mtd, loff_t from)
 static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
                     size_t *retlen, u_char *buf)
 {
-        /* Just a special case of doc_read_ecc */
-        return doc_read_ecc(mtd, from, len, retlen, buf, NULL, NULL);
-}
-
-static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
-                        size_t *retlen, u_char *buf, u_char *eccbuf,
-                        struct nand_oobinfo *oobsel)
-{
         int ret, i;
         volatile char dummy;
         loff_t fofs;
-        unsigned char syndrome[6];
+        unsigned char syndrome[6], eccbuf[6];
         struct DiskOnChip *this = mtd->priv;
         void __iomem * docptr = this->virtadr;
         struct Nand *mychip = &this->chips[from >> (this->chipshift)];
@@ -644,56 +630,51 @@ static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
         WriteDOC(0, docptr, Mplus_FlashControl);
         DoC_WaitReady(docptr);
 
-        if (eccbuf) {
-                /* init the ECC engine, see Reed-Solomon EDC/ECC 11.1 .*/
-                WriteDOC(DOC_ECC_RESET, docptr, Mplus_ECCConf);
-                WriteDOC(DOC_ECC_EN, docptr, Mplus_ECCConf);
-        } else {
-                /* disable the ECC engine */
-                WriteDOC(DOC_ECC_RESET, docptr, Mplus_ECCConf);
-        }
+        /* init the ECC engine, see Reed-Solomon EDC/ECC 11.1 .*/
+        WriteDOC(DOC_ECC_RESET, docptr, Mplus_ECCConf);
+        WriteDOC(DOC_ECC_EN, docptr, Mplus_ECCConf);
 
         /* Let the caller know we completed it */
         *retlen = len;
-        ret = 0;
+        ret = 0;
 
         ReadDOC(docptr, Mplus_ReadPipeInit);
         ReadDOC(docptr, Mplus_ReadPipeInit);
 
-        if (eccbuf) {
-                /* Read the data via the internal pipeline through CDSN IO
-                   register, see Pipelined Read Operations 11.3 */
-                MemReadDOC(docptr, buf, len);
+        /* Read the data via the internal pipeline through CDSN IO
+           register, see Pipelined Read Operations 11.3 */
+        MemReadDOC(docptr, buf, len);
 
-                /* Read the ECC data following raw data */
-                MemReadDOC(docptr, eccbuf, 4);
-                eccbuf[4] = ReadDOC(docptr, Mplus_LastDataRead);
-                eccbuf[5] = ReadDOC(docptr, Mplus_LastDataRead);
+        /* Read the ECC data following raw data */
+        MemReadDOC(docptr, eccbuf, 4);
+        eccbuf[4] = ReadDOC(docptr, Mplus_LastDataRead);
+        eccbuf[5] = ReadDOC(docptr, Mplus_LastDataRead);
 
-                /* Flush the pipeline */
-                dummy = ReadDOC(docptr, Mplus_ECCConf);
-                dummy = ReadDOC(docptr, Mplus_ECCConf);
+        /* Flush the pipeline */
+        dummy = ReadDOC(docptr, Mplus_ECCConf);
+        dummy = ReadDOC(docptr, Mplus_ECCConf);
 
-                /* Check the ECC Status */
-                if (ReadDOC(docptr, Mplus_ECCConf) & 0x80) {
-                        int nb_errors;
-                        /* There was an ECC error */
+        /* Check the ECC Status */
+        if (ReadDOC(docptr, Mplus_ECCConf) & 0x80) {
+                int nb_errors;
+                /* There was an ECC error */
 #ifdef ECC_DEBUG
-                        printk("DiskOnChip ECC Error: Read at %lx\n", (long)from);
+                printk("DiskOnChip ECC Error: Read at %lx\n", (long)from);
 #endif
-                        /* Read the ECC syndrom through the DiskOnChip ECC logic.
-                           These syndrome will be all ZERO when there is no error */
-                        for (i = 0; i < 6; i++)
-                                syndrome[i] = ReadDOC(docptr, Mplus_ECCSyndrome0 + i);
+                /* Read the ECC syndrom through the DiskOnChip ECC logic.
+                   These syndrome will be all ZERO when there is no error */
+                for (i = 0; i < 6; i++)
+                        syndrome[i] = ReadDOC(docptr, Mplus_ECCSyndrome0 + i);
 
-                        nb_errors = doc_decode_ecc(buf, syndrome);
+                nb_errors = doc_decode_ecc(buf, syndrome);
 #ifdef ECC_DEBUG
-                        printk("ECC Errors corrected: %x\n", nb_errors);
+                printk("ECC Errors corrected: %x\n", nb_errors);
 #endif
-                        if (nb_errors < 0) {
-                                /* We return error, but have actually done the read. Not that
-                                   this can be told to user-space, via sys_read(), but at least
-                                   MTD-aware stuff can know about it by checking *retlen */
+                if (nb_errors < 0) {
+                        /* We return error, but have actually done the
+                           read. Not that this can be told to user-space, via
+                           sys_read(), but at least MTD-aware stuff can know
+                           about it by checking *retlen */
 #ifdef ECC_DEBUG
                         printk("%s(%d): Millennium Plus ECC error (from=0x%x:\n",
                                 __FILE__, __LINE__, (int)from);
@@ -707,24 +688,16 @@ static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
                                 eccbuf[3], eccbuf[4], eccbuf[5]);
 #endif
                                 ret = -EIO;
-                        }
                 }
+        }
 
 #ifdef PSYCHO_DEBUG
-                printk("ECC DATA at %lx: %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
-                       (long)from, eccbuf[0], eccbuf[1], eccbuf[2], eccbuf[3],
-                       eccbuf[4], eccbuf[5]);
+        printk("ECC DATA at %lx: %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
+               (long)from, eccbuf[0], eccbuf[1], eccbuf[2], eccbuf[3],
+               eccbuf[4], eccbuf[5]);
 #endif
-
-                /* disable the ECC engine */
-                WriteDOC(DOC_ECC_DIS, docptr , Mplus_ECCConf);
-        } else {
-                /* Read the data via the internal pipeline through CDSN IO
-                   register, see Pipelined Read Operations 11.3 */
-                MemReadDOC(docptr, buf, len-2);
-                buf[len-2] = ReadDOC(docptr, Mplus_LastDataRead);
-                buf[len-1] = ReadDOC(docptr, Mplus_LastDataRead);
-        }
+        /* disable the ECC engine */
+        WriteDOC(DOC_ECC_DIS, docptr , Mplus_ECCConf);
 
         /* Disable flash internally */
         WriteDOC(0, docptr, Mplus_FlashSelect);
@@ -735,17 +708,10 @@ static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
 static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
                      size_t *retlen, const u_char *buf)
 {
-        char eccbuf[6];
-        return doc_write_ecc(mtd, to, len, retlen, buf, eccbuf, NULL);
-}
-
-static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
-                         size_t *retlen, const u_char *buf, u_char *eccbuf,
-                         struct nand_oobinfo *oobsel)
-{
         int i, before, ret = 0;
         loff_t fto;
         volatile char dummy;
+        char eccbuf[6];
         struct DiskOnChip *this = mtd->priv;
         void __iomem * docptr = this->virtadr;
         struct Nand *mychip = &this->chips[to >> (this->chipshift)];
@@ -795,46 +761,42 @@ static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
         /* Disable the ECC engine */
         WriteDOC(DOC_ECC_RESET, docptr, Mplus_ECCConf);
 
-        if (eccbuf) {
-                if (before) {
-                        /* Write the block status BLOCK_USED (0x5555) */
-                        WriteDOC(0x55, docptr, Mil_CDSN_IO);
-                        WriteDOC(0x55, docptr, Mil_CDSN_IO);
-                }
-
-                /* init the ECC engine, see Reed-Solomon EDC/ECC 11.1 .*/
-                WriteDOC(DOC_ECC_EN | DOC_ECC_RW, docptr, Mplus_ECCConf);
+        if (before) {
+                /* Write the block status BLOCK_USED (0x5555) */
+                WriteDOC(0x55, docptr, Mil_CDSN_IO);
+                WriteDOC(0x55, docptr, Mil_CDSN_IO);
         }
 
+        /* init the ECC engine, see Reed-Solomon EDC/ECC 11.1 .*/
+        WriteDOC(DOC_ECC_EN | DOC_ECC_RW, docptr, Mplus_ECCConf);
+
         MemWriteDOC(docptr, (unsigned char *) buf, len);
 
-        if (eccbuf) {
-                /* Write ECC data to flash, the ECC info is generated by
-                   the DiskOnChip ECC logic see Reed-Solomon EDC/ECC 11.1 */
-                DoC_Delay(docptr, 3);
+        /* Write ECC data to flash, the ECC info is generated by
+           the DiskOnChip ECC logic see Reed-Solomon EDC/ECC 11.1 */
+        DoC_Delay(docptr, 3);
 
-                /* Read the ECC data through the DiskOnChip ECC logic */
-                for (i = 0; i < 6; i++)
-                        eccbuf[i] = ReadDOC(docptr, Mplus_ECCSyndrome0 + i);
+        /* Read the ECC data through the DiskOnChip ECC logic */
+        for (i = 0; i < 6; i++)
+                eccbuf[i] = ReadDOC(docptr, Mplus_ECCSyndrome0 + i);
 
-                /* disable the ECC engine */
-                WriteDOC(DOC_ECC_DIS, docptr, Mplus_ECCConf);
+        /* disable the ECC engine */
+        WriteDOC(DOC_ECC_DIS, docptr, Mplus_ECCConf);
 
-                /* Write the ECC data to flash */
-                MemWriteDOC(docptr, eccbuf, 6);
+        /* Write the ECC data to flash */
+        MemWriteDOC(docptr, eccbuf, 6);
 
-                if (!before) {
-                        /* Write the block status BLOCK_USED (0x5555) */
-                        WriteDOC(0x55, docptr, Mil_CDSN_IO+6);
-                        WriteDOC(0x55, docptr, Mil_CDSN_IO+7);
-                }
+        if (!before) {
+                /* Write the block status BLOCK_USED (0x5555) */
+                WriteDOC(0x55, docptr, Mil_CDSN_IO+6);
+                WriteDOC(0x55, docptr, Mil_CDSN_IO+7);
+        }
 
 #ifdef PSYCHO_DEBUG
-                printk("OOB data at %lx is %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
-                       (long) to, eccbuf[0], eccbuf[1], eccbuf[2], eccbuf[3],
-                       eccbuf[4], eccbuf[5]);
+        printk("OOB data at %lx is %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
+               (long) to, eccbuf[0], eccbuf[1], eccbuf[2], eccbuf[3],
+               eccbuf[4], eccbuf[5]);
 #endif
-        }
 
         WriteDOC(0x00, docptr, Mplus_WritePipeTerm);
         WriteDOC(0x00, docptr, Mplus_WritePipeTerm);