From: Ezequiel García Date: Mon, 28 Dec 2015 20:54:51 +0000 (-0300) Subject: mtd: spi-nor: wait until lock/unlock operations are ready X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=32321e950d8a;p=linux-beck.git mtd: spi-nor: wait until lock/unlock operations are ready On Micron and Numonyx devices, the status register write command (WRSR), raises a work-in-progress bit (WIP) on the status register. The datasheets for these devices specify that while the status register write is in progress, the status register WIP bit can still be read to check the end of the operation. This commit adds a wait_till_ready call on lock/unlock operations, which is required for Micron and Numonyx but should be harmless for others. This is needed to prevent applications from issuing erase or program operations before the unlock operation is completed. Reported-by: Stas Sergeev Signed-off-by: Ezequiel Garcia Signed-off-by: Brian Norris --- diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index f8f36d47575f..ed0c19c558b5 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -481,6 +481,7 @@ static int stm_lock(struct spi_nor *nor, loff_t ofs, uint64_t len) int status_old, status_new; u8 mask = SR_BP2 | SR_BP1 | SR_BP0; u8 shift = ffs(mask) - 1, pow, val; + int ret; status_old = read_sr(nor); if (status_old < 0) @@ -519,7 +520,10 @@ static int stm_lock(struct spi_nor *nor, loff_t ofs, uint64_t len) return -EINVAL; write_enable(nor); - return write_sr(nor, status_new); + ret = write_sr(nor, status_new); + if (ret) + return ret; + return spi_nor_wait_till_ready(nor); } /* @@ -533,6 +537,7 @@ static int stm_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) int status_old, status_new; u8 mask = SR_BP2 | SR_BP1 | SR_BP0; u8 shift = ffs(mask) - 1, pow, val; + int ret; status_old = read_sr(nor); if (status_old < 0) @@ -569,7 +574,10 @@ static int stm_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) return -EINVAL; write_enable(nor); - return write_sr(nor, status_new); + ret = write_sr(nor, status_new); + if (ret) + return ret; + return spi_nor_wait_till_ready(nor); } /*