From: Boris Brezillon <[email protected]>

commit e45a4b652dbd2f8b5a3b8e97e89f602a58cb28aa upstream.

Mimic what's done in nand_soft_waitrdy() and add one to the jiffies
timeout so we don't end up waiting less than actually required.

Reported-by: Tudor Ambarus <[email protected]>
Fixes: b0e137ad24b6c ("mtd: rawnand: Provide helper for polling GPIO R/B pin")
Cc: <[email protected]>
Signed-off-by: Boris Brezillon <[email protected]>
Reviewed-by: Tudor Ambarus <[email protected]>
Signed-off-by: Miquel Raynal <[email protected]>
Link: 
https://lore.kernel.org/linux-mtd/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/mtd/nand/raw/nand_base.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -736,8 +736,14 @@ EXPORT_SYMBOL_GPL(nand_soft_waitrdy);
 int nand_gpio_waitrdy(struct nand_chip *chip, struct gpio_desc *gpiod,
                      unsigned long timeout_ms)
 {
-       /* Wait until R/B pin indicates chip is ready or timeout occurs */
-       timeout_ms = jiffies + msecs_to_jiffies(timeout_ms);
+
+       /*
+        * Wait until R/B pin indicates chip is ready or timeout occurs.
+        * +1 below is necessary because if we are now in the last fraction
+        * of jiffy and msecs_to_jiffies is 1 then we will wait only that
+        * small jiffy fraction - possibly leading to false timeout.
+        */
+       timeout_ms = jiffies + msecs_to_jiffies(timeout_ms) + 1;
        do {
                if (gpiod_get_value_cansleep(gpiod))
                        return 0;


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