[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 66cb1e5..92dbb47 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);