This is a note to let you know that I've just added the patch titled
mtd: nand: fix interpretation of NAND_CMD_NONE in nand_command[_lp]()
to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: mtd-nand-fix-interpretation-of-nand_cmd_none-in-nand_command.patch and it can be found in the queue-4.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Fri Mar 16 15:11:07 CET 2018
From: Miquel Raynal miquel.raynal@free-electrons.com Date: Wed, 8 Nov 2017 17:00:27 +0100 Subject: mtd: nand: fix interpretation of NAND_CMD_NONE in nand_command[_lp]()
From: Miquel Raynal miquel.raynal@free-electrons.com
[ Upstream commit df467899da0b71465760b4e35127bce837244eee ]
Some drivers (like nand_hynix.c) call ->cmdfunc() with NAND_CMD_NONE and a column address and expect the controller to only send address cycles. Right now, the default ->cmdfunc() implementations provided by the core do not filter out the command cycle in this case and forwards the request to the controller driver through the ->cmd_ctrl() method. The thing is, NAND controller drivers can get this wrong and send a command cycle with a NAND_CMD_NONE opcode and since NAND_CMD_NONE is -1, and the command field is usually casted to an u8, we end up sending the 0xFF command which is actually a RESET operation.
Add conditions in nand_command[_lp]() functions to sending the initial command cycle when command == NAND_CMD_NONE.
Signed-off-by: Miquel Raynal miquel.raynal@free-electrons.com Signed-off-by: Boris Brezillon boris.brezillon@free-electrons.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/mtd/nand/nand_base.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
--- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -710,7 +710,8 @@ static void nand_command(struct mtd_info chip->cmd_ctrl(mtd, readcmd, ctrl); ctrl &= ~NAND_CTRL_CHANGE; } - chip->cmd_ctrl(mtd, command, ctrl); + if (command != NAND_CMD_NONE) + chip->cmd_ctrl(mtd, command, ctrl);
/* Address cycle, when necessary */ ctrl = NAND_CTRL_ALE | NAND_CTRL_CHANGE; @@ -738,6 +739,7 @@ static void nand_command(struct mtd_info */ switch (command) {
+ case NAND_CMD_NONE: case NAND_CMD_PAGEPROG: case NAND_CMD_ERASE1: case NAND_CMD_ERASE2: @@ -831,7 +833,9 @@ static void nand_command_lp(struct mtd_i }
/* Command latch cycle */ - chip->cmd_ctrl(mtd, command, NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE); + if (command != NAND_CMD_NONE) + chip->cmd_ctrl(mtd, command, + NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
if (column != -1 || page_addr != -1) { int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE; @@ -866,6 +870,7 @@ static void nand_command_lp(struct mtd_i */ switch (command) {
+ case NAND_CMD_NONE: case NAND_CMD_CACHEDPROG: case NAND_CMD_PAGEPROG: case NAND_CMD_ERASE1:
Patches currently in stable-queue which might be from miquel.raynal@free-electrons.com are
queue-4.15/mtd-nand-fix-interpretation-of-nand_cmd_none-in-nand_command.patch