mtd: vf610_nfc: remove caching of page in buffer

To improve performance we remember the current page in the buffer
and avoid reading it twice. This implicit page cache increases
complexity while does not increase performance in real world cases.
This patch removes that feature.

Acked-by: Bill Pringlemeir <bpringlemeir@nbsps.com>
Signed-off-by: Stefan Agner <stefan@agner.ch>
diff --git a/drivers/mtd/nand/vf610_nfc.c b/drivers/mtd/nand/vf610_nfc.c
index d98dd28..fa0bb9d 100644
--- a/drivers/mtd/nand/vf610_nfc.c
+++ b/drivers/mtd/nand/vf610_nfc.c
@@ -147,7 +147,6 @@
 	uint               column;
 	int                spareonly;
 	int		   page_sz;
-	int                page;
 	/* Status and ID are in alternate locations. */
 	int                alt_buf;
 #define ALT_BUF_ID   1
@@ -347,7 +346,6 @@
 
 	switch (command) {
 	case NAND_CMD_PAGEPROG:
-		nfc->page = -1;
 		vf610_nfc_transfer_size(nfc->regs, nfc->page_sz);
 		vf610_nfc_send_commands(nfc->regs, NAND_CMD_SEQIN,
 					command, PROGRAM_PAGE_CMD_CODE);
@@ -367,10 +365,6 @@
 	case NAND_CMD_SEQIN: /* Pre-read for partial writes. */
 	case NAND_CMD_READ0:
 		column = 0;
-		/* Already read? */
-		if (nfc->page == page)
-			return;
-		nfc->page = page;
 		vf610_nfc_transfer_size(nfc->regs, nfc->page_sz);
 		vf610_nfc_send_commands(nfc->regs, NAND_CMD_READ0,
 					NAND_CMD_READSTART, READ_PAGE_CMD_CODE);
@@ -378,7 +372,6 @@
 		break;
 
 	case NAND_CMD_ERASE1:
-		nfc->page = -1;
 		vf610_nfc_transfer_size(nfc->regs, 0);
 		vf610_nfc_send_commands(nfc->regs, command,
 					NAND_CMD_ERASE2, ERASE_CMD_CODE);
@@ -532,10 +525,8 @@
 	flip = count_written_bits(dat, nfc->chip.ecc.size, ecc_count);
 
 	/* ECC failed. */
-	if (flip > ecc_count) {
-		nfc->page = -1;
+	if (flip > ecc_count)
 		return -1;
-	}
 
 	/* Erased page. */
 	memset(dat, 0xff, nfc->chip.ecc.size);