From e892dea7229d56b75c46a76b9039f9e179584a91 Mon Sep 17 00:00:00 2001 From: Yunhui Cui Date: Mon, 1 Feb 2016 18:48:49 +0800 Subject: [PATCH 100/113] mtd:spi_nor: Disable Micron flash HW protection For Micron family ,The status register write enable/disable bit, provides hardware data protection for the device. When the enable/disable bit is set to 1, the status register nonvolatile bits become read-only and the WRITE STATUS REGISTER operation will not execute. Signed-off-by: Yunhui Cui --- drivers/mtd/spi-nor/spi-nor.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -39,6 +39,7 @@ #define SPI_NOR_MAX_ID_LEN 6 #define SPI_NOR_MAX_ADDR_WIDTH 4 +#define SPI_NOR_MICRON_WRITE_ENABLE 0x7f struct flash_info { char *name; @@ -1252,6 +1253,14 @@ int spi_nor_scan(struct spi_nor *nor, co if (ret) return ret; + if (JEDEC_MFR(info) == SNOR_MFR_MICRON) { + ret = read_sr(nor); + ret &= SPI_NOR_MICRON_WRITE_ENABLE; + + write_enable(nor); + write_sr(nor, ret); + } + if (!mtd->name) mtd->name = dev_name(dev); mtd->priv = nor;