From: Matthias Schiffer Date: Sat, 7 May 2016 00:17:55 +0200 Subject: kernel: mtd: spi-nor: wait until status register writes are ready diff --git a/target/linux/generic/patches-3.18/094-0001-mtd-spi-nor-wait-until-lock-unlock-operations-are-re.patch b/target/linux/generic/patches-3.18/094-0001-mtd-spi-nor-wait-until-lock-unlock-operations-are-re.patch new file mode 100644 index 0000000..2c2e5f3 --- /dev/null +++ b/target/linux/generic/patches-3.18/094-0001-mtd-spi-nor-wait-until-lock-unlock-operations-are-re.patch @@ -0,0 +1,66 @@ +From 32321e950d8a237d7e8f3a9b76220007dfa87544 Mon Sep 17 00:00:00 2001 +Message-Id: <32321e950d8a237d7e8f3a9b76220007dfa87544.1462572686.git.mschiffer@universe-factory.net> +From: =?UTF-8?q?Ezequiel=20Garc=C3=ADa?= +Date: Mon, 28 Dec 2015 17:54:51 -0300 +Subject: [PATCH] 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 +--- + drivers/mtd/spi-nor/spi-nor.c | 12 ++++++++++-- + 1 file changed, 10 insertions(+), 2 deletions(-) + +--- a/drivers/mtd/spi-nor/spi-nor.c ++++ b/drivers/mtd/spi-nor/spi-nor.c +@@ -462,6 +462,7 @@ static int stm_lock(struct spi_nor *nor, + u8 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); + +@@ -498,7 +499,10 @@ static int stm_lock(struct spi_nor *nor, + 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); + } + + /* +@@ -512,6 +516,7 @@ static int stm_unlock(struct spi_nor *no + uint8_t 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); + +@@ -546,7 +551,10 @@ static int stm_unlock(struct spi_nor *no + 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); + } + + /* diff --git a/target/linux/generic/patches-3.18/094-0002-mtd-spi-nor-wait-for-SR_WIP-to-clear-on-initial-unlo.patch b/target/linux/generic/patches-3.18/094-0002-mtd-spi-nor-wait-for-SR_WIP-to-clear-on-initial-unlo.patch new file mode 100644 index 0000000..a0573d5 --- /dev/null +++ b/target/linux/generic/patches-3.18/094-0002-mtd-spi-nor-wait-for-SR_WIP-to-clear-on-initial-unlo.patch @@ -0,0 +1,33 @@ +From edf891ef9ab773363f8e58022a26d7d31604aed6 Mon Sep 17 00:00:00 2001 +Message-Id: +From: Brian Norris +Date: Fri, 29 Jan 2016 11:25:30 -0800 +Subject: [PATCH] mtd: spi-nor: wait for SR_WIP to clear on initial unlock + +Fixup a piece leftover by commit 32321e950d8a ("mtd: spi-nor: wait until +lock/unlock operations are ready"). That commit made us wait for the WIP +bit to settle after lock/unlock operations, but it missed the open-coded +"unlock" that happens at probe() time. + +We should probably have this code utilize the unlock() routines in the +future, to avoid duplication, but unfortunately, flash which need to be +unlocked don't all have a proper ->flash_unlock() callback. + +Signed-off-by: Brian Norris +Cc: Stas Sergeev +Reviewed-by: Ezequiel Garcia +Tested-by: Ezequiel Garcia +--- + drivers/mtd/spi-nor/spi-nor.c | 1 + + 1 file changed, 1 insertion(+) + +--- a/drivers/mtd/spi-nor/spi-nor.c ++++ b/drivers/mtd/spi-nor/spi-nor.c +@@ -1167,6 +1167,7 @@ int spi_nor_scan(struct spi_nor *nor, co + JEDEC_MFR(info) == SNOR_MFR_SST) { + write_enable(nor); + write_sr(nor, 0); ++ spi_nor_wait_till_ready(nor); + } + + if (!mtd->name)