4.14-stable review patch. If anyone has any objections, please let me know.
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From: William Zhang william.zhang@broadcom.com
commit 9cc0a598b944816f2968baf2631757f22721b996 upstream.
If system is busy during the command status polling function, the driver may not get the chance to poll the status register till the end of time out and return the premature status. Do a final check after time out happens to ensure reading the correct status.
Fixes: 9d2ee0a60b8b ("mtd: nand: brcmnand: Check flash #WP pin status before nand erase/program") Signed-off-by: William Zhang william.zhang@broadcom.com Reviewed-by: Florian Fainelli florian.fainelli@broadcom.com Cc: stable@vger.kernel.org Signed-off-by: Miquel Raynal miquel.raynal@bootlin.com Link: https://lore.kernel.org/linux-mtd/20230706182909.79151-3-william.zhang@broad... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/mtd/nand/brcmnand/brcmnand.c | 8 ++++++++ 1 file changed, 8 insertions(+)
--- a/drivers/mtd/nand/brcmnand/brcmnand.c +++ b/drivers/mtd/nand/brcmnand/brcmnand.c @@ -836,6 +836,14 @@ static int bcmnand_ctrl_poll_status(stru cpu_relax(); } while (time_after(limit, jiffies));
+ /* + * do a final check after time out in case the CPU was busy and the driver + * did not get enough time to perform the polling to avoid false alarms + */ + val = brcmnand_read_reg(ctrl, BRCMNAND_INTFC_STATUS); + if ((val & mask) == expected_val) + return 0; + dev_warn(ctrl->dev, "timeout on status poll (expected %x got %x)\n", expected_val, val & mask);