From: Miquel Raynal Date: Wed, 8 Nov 2017 16:00:27 +0000 (+0100) Subject: mtd: nand: fix interpretation of NAND_CMD_NONE in nand_command[_lp]() X-Git-Tag: v4.1.52~483 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d8249dcd54804e3baf6f595cf650188f017d4c21;p=thirdparty%2Fkernel%2Fstable.git mtd: nand: fix interpretation of NAND_CMD_NONE in nand_command[_lp]() [ 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 Signed-off-by: Boris Brezillon Signed-off-by: Sasha Levin --- diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 14a5f559e300f..eb5ff54c9263c 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -618,7 +618,8 @@ static void nand_command(struct mtd_info *mtd, unsigned int command, 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; @@ -647,6 +648,7 @@ static void nand_command(struct mtd_info *mtd, unsigned int command, */ switch (command) { + case NAND_CMD_NONE: case NAND_CMD_PAGEPROG: case NAND_CMD_ERASE1: case NAND_CMD_ERASE2: @@ -709,7 +711,9 @@ static void nand_command_lp(struct mtd_info *mtd, unsigned int command, } /* 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; @@ -742,6 +746,7 @@ static void nand_command_lp(struct mtd_info *mtd, unsigned int command, */ switch (command) { + case NAND_CMD_NONE: case NAND_CMD_CACHEDPROG: case NAND_CMD_PAGEPROG: case NAND_CMD_ERASE1: