[U-Boot] [PATCH] Revert "spi: add config option to enable the WP pin function on st micron flashes"

[Jagannadha Sutradharudu Teki]

This reverts commit 562f8df18da62ae02c4ace1e530451fe82c3312d.

Never see the issue with N25Q128 flash without need of W#/Vpp signal
during probe.

Signed-off-by: Jagannadha Sutradharudu Teki <jagannadh.teki at gmail.com>
Cc: Heiko Schocher <hs at denx.de>
---
 README                        | 11 -----------
 drivers/mtd/spi/sf_internal.h |  4 ----
 drivers/mtd/spi/sf_probe.c    | 30 ------------------------------
 3 files changed, 45 deletions(-)

diff --git a/README b/README
index 4ca04d0..908646f 100644
--- a/README
+++ b/README
@@ -3090,17 +3090,6 @@ CBFS (Coreboot Filesystem) support
 		memories can be connected with a given cs line.
 		currently Xilinx Zynq qspi support these type of connections.
 
-		CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
-		enable the W#/Vpp signal to disable writing to the status
-		register on ST MICRON flashes like the N25Q128.
-		The status register write enable/disable bit, combined with
-		the W#/VPP signal provides hardware data protection for the
-		device as follows: When the enable/disable bit is set to 1,
-		and the W#/VPP signal is driven LOW, the status register
-		nonvolatile bits become read-only and the WRITE STATUS REGISTER
-		operation will not execute. The only way to exit this
-		hardware-protected mode is to drive W#/VPP HIGH.
-
 - SystemACE Support:
 		CONFIG_SYSTEMACE
 
diff --git a/drivers/mtd/spi/sf_internal.h b/drivers/mtd/spi/sf_internal.h
index 785f7a9..bd834dc 100644
--- a/drivers/mtd/spi/sf_internal.h
+++ b/drivers/mtd/spi/sf_internal.h
@@ -97,10 +97,6 @@ enum {
 #define STATUS_QEB_MXIC		(1 << 6)
 #define STATUS_PEC			(1 << 7)
 
-#ifdef CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
-#define STATUS_SRWD			(1 << 7) /* SR write protect */
-#endif
-
 /* Flash timeout values */
 #define SPI_FLASH_PROG_TIMEOUT		(2 * CONFIG_SYS_HZ)
 #define SPI_FLASH_PAGE_ERASE_TIMEOUT		(5 * CONFIG_SYS_HZ)
diff --git a/drivers/mtd/spi/sf_probe.c b/drivers/mtd/spi/sf_probe.c
index ce9987f..3b0e652 100644
--- a/drivers/mtd/spi/sf_probe.c
+++ b/drivers/mtd/spi/sf_probe.c
@@ -287,34 +287,6 @@ int spi_flash_decode_fdt(const void *blob, struct spi_flash *flash)
 }
 #endif /* CONFIG_OF_CONTROL */
 
-#ifdef CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
-/* enable the W#/Vpp signal to disable writing to the status register */
-static int spi_enable_wp_pin(struct spi_flash *flash)
-{
-	u8 status;
-	int ret;
-
-	ret = spi_flash_cmd_read_status(flash, &status);
-	if (ret < 0)
-		return ret;
-
-	ret = spi_flash_cmd_write_status(flash, STATUS_SRWD);
-	if (ret < 0)
-		return ret;
-
-	ret = spi_flash_cmd_write_disable(flash);
-	if (ret < 0)
-		return ret;
-
-	return 0;
-}
-#else
-static int spi_enable_wp_pin(struct spi_flash *flash)
-{
-	return 0;
-}
-#endif
-
 /**
  * spi_flash_probe_slave() - Probe for a SPI flash device on a bus
  *
@@ -393,8 +365,6 @@ int spi_flash_probe_slave(struct spi_slave *spi, struct spi_flash *flash)
 		puts(" Full access #define CONFIG_SPI_FLASH_BAR\n");
 	}
 #endif
-	if (spi_enable_wp_pin(flash))
-		puts("Enable WP pin failed\n");
 
 	/* Release spi bus */
 	spi_release_bus(spi);
-- 
1.9.1