mtd: nand: fix interpretation of NAND_CMD_NONE in nand_command[_lp]()

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>
This commit is contained in:
Miquel Raynal 2017-11-08 17:00:27 +01:00 committed by Boris Brezillon
parent b13a9735ae
commit df467899da
1 changed files with 7 additions and 2 deletions

View File

@ -710,6 +710,7 @@ static void nand_command(struct mtd_info *mtd, unsigned int command,
chip->cmd_ctrl(mtd, readcmd, ctrl);
ctrl &= ~NAND_CTRL_CHANGE;
}
if (command != NAND_CMD_NONE)
chip->cmd_ctrl(mtd, command, ctrl);
/* Address cycle, when necessary */
@ -738,6 +739,7 @@ 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:
@ -831,7 +833,9 @@ 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;
@ -866,6 +870,7 @@ 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: