diff --git a/drivers/mtd/spi/sf_params.c b/drivers/mtd/spi/sf_params.c
index eb372b757557260d9b6f51f264d9a363f9de948a..ac886fd071c0190e0b470c7d6d6863b8ed187ff9 100644
--- a/drivers/mtd/spi/sf_params.c
+++ b/drivers/mtd/spi/sf_params.c
@@ -60,6 +60,7 @@ const struct spi_flash_params spi_flash_params_table[] = {
 	{"S25FL256S_64K",  0x010219, 0x4d01,	64 * 1024,   512, RD_FULL,		     WR_QPP},
 	{"S25FL512S_256K", 0x010220, 0x4d00,   256 * 1024,   256, RD_FULL,		     WR_QPP},
 	{"S25FL512S_64K",  0x010220, 0x4d01,    64 * 1024,  1024, RD_FULL,		     WR_QPP},
+	{"S25FL512S_512K", 0x010220, 0x4f00,   256 * 1024,   256, RD_FULL,		     WR_QPP},
 #endif
 #ifdef CONFIG_SPI_FLASH_STMICRO		/* STMICRO */
 	{"M25P10",	   0x202011, 0x0,	32 * 1024,     4,	0,			  0},
diff --git a/drivers/mtd/spi/sf_probe.c b/drivers/mtd/spi/sf_probe.c
index 0a46fe38da6899fd4c26702ec1981a720828c532..36ae5e0a7736f4b46c3570b42bd2c8aa26bb6822 100644
--- a/drivers/mtd/spi/sf_probe.c
+++ b/drivers/mtd/spi/sf_probe.c
@@ -197,16 +197,6 @@ static struct spi_flash *spi_flash_validate_params(struct spi_slave *spi,
 		/* Go for default supported write cmd */
 		flash->write_cmd = CMD_PAGE_PROGRAM;
 
-	/* Set the quad enable bit - only for quad commands */
-	if ((flash->read_cmd == CMD_READ_QUAD_OUTPUT_FAST) ||
-	    (flash->read_cmd == CMD_READ_QUAD_IO_FAST) ||
-	    (flash->write_cmd == CMD_QUAD_PAGE_PROGRAM)) {
-		if (spi_flash_set_qeb(flash, idcode[0])) {
-			debug("SF: Fail to set QEB for %02x\n", idcode[0]);
-			return NULL;
-		}
-	}
-
 	/* Read dummy_byte: dummy byte is determined based on the
 	 * dummy cycles of a particular command.
 	 * Fast commands - dummy_byte = dummy_cycles/8
@@ -327,6 +317,16 @@ static struct spi_flash *spi_flash_probe_slave(struct spi_slave *spi)
 	if (!flash)
 		goto err_read_id;
 
+	/* Set the quad enable bit - only for quad commands */
+	if ((flash->read_cmd == CMD_READ_QUAD_OUTPUT_FAST) ||
+	    (flash->read_cmd == CMD_READ_QUAD_IO_FAST) ||
+	    (flash->write_cmd == CMD_QUAD_PAGE_PROGRAM)) {
+		if (spi_flash_set_qeb(flash, idcode[0])) {
+			debug("SF: Fail to set QEB for %02x\n", idcode[0]);
+			return NULL;
+		}
+	}
+
 #ifdef CONFIG_OF_CONTROL
 	if (spi_flash_decode_fdt(gd->fdt_blob, flash)) {
 		debug("SF: FDT decode error\n");
diff --git a/drivers/spi/soft_spi.c b/drivers/spi/soft_spi.c
index 5d22351290b6337280434cca41e2dd3372c504d2..c969be31eb31828066e2c044c825529d6412db69 100644
--- a/drivers/spi/soft_spi.c
+++ b/drivers/spi/soft_spi.c
@@ -136,10 +136,14 @@ int  spi_xfer(struct spi_slave *slave, unsigned int bitlen,
 		/*
 		 * Check if it is time to work on a new byte.
 		 */
-		if((j % 8) == 0) {
-			tmpdout = *txd++;
+		if ((j % 8) == 0) {
+			if (txd)
+				tmpdout = *txd++;
+			else
+				tmpdout = 0;
 			if(j != 0) {
-				*rxd++ = tmpdin;
+				if (rxd)
+					*rxd++ = tmpdin;
 			}
 			tmpdin  = 0;
 		}
@@ -164,9 +168,11 @@ int  spi_xfer(struct spi_slave *slave, unsigned int bitlen,
 	 * bits over to left-justify them.  Then store the last byte
 	 * read in.
 	 */
-	if((bitlen % 8) != 0)
-		tmpdin <<= 8 - (bitlen % 8);
-	*rxd++ = tmpdin;
+	if (rxd) {
+		if ((bitlen % 8) != 0)
+			tmpdin <<= 8 - (bitlen % 8);
+		*rxd++ = tmpdin;
+	}
 
 	if (flags & SPI_XFER_END)
 		spi_cs_deactivate(slave);