This patch adds Global block protection unlock support for SST flash parts
Signed-off-by: Anurag Kumar Vulisha <[email protected]>
---
drivers/mtd/spi-nor/spi-nor.c | 8 ++++++++
include/linux/mtd/spi-nor.h | 1 +
2 files changed, 9 insertions(+)
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 4988390..787ab95 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -68,6 +68,8 @@ struct flash_info {
#define SPI_NOR_DUAL_READ 0x20 /* Flash supports Dual Read */
#define SPI_NOR_QUAD_READ 0x40 /* Flash supports Quad Read */
#define USE_FSR 0x80 /* use flag status register */
+/* Unlock the Global protection for sst flashes */
+#define SST_GLOBAL_PROT_UNLK 0x100
};
#define JEDEC_MFR(info) ((info)->id[0])
@@ -1204,6 +1206,12 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode)
JEDEC_MFR(info) == SNOR_MFR_WINBOND) {
write_enable(nor);
write_sr(nor, 0);
+
+ if (info->flags & SST_GLOBAL_PROT_UNLK) {
+ write_enable(nor);
+ /* Unlock global write protection bits */
+ nor->write_reg(nor, GLOBAL_BLKPROT_UNLK, NULL, 0);
+ }
}
if (!mtd->name)
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index c8723b6..37e1abf 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -65,6 +65,7 @@
#define SPINOR_OP_BP 0x02 /* Byte program */
#define SPINOR_OP_WRDI 0x04 /* Write disable */
#define SPINOR_OP_AAI_WP 0xad /* Auto address increment word program */
+#define GLOBAL_BLKPROT_UNLK 0x98 /* Clear global write protection bits */
/* Used for Macronix and Winbond flashes. */
#define SPINOR_OP_EN4B 0xb7 /* Enter 4-byte mode */
--
2.1.2