In r852_ready(), the dev get from r852_get_dev() need to be checked. An unstable device should not be ready. A proper implementation can be found in r852_read_byte(). Add a status check and return 0 when it is unstable.

Fixes: 50a487e7719c ("mtd: rawnand: Pass a nand_chip object to chip->dev_ready()") Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Wentao Liang vulab@iscas.ac.cn --- drivers/mtd/nand/raw/r852.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/drivers/mtd/nand/raw/r852.c b/drivers/mtd/nand/raw/r852.c index b07c2f8b4035..918974d088cf 100644 --- a/drivers/mtd/nand/raw/r852.c +++ b/drivers/mtd/nand/raw/r852.c @@ -387,6 +387,9 @@ static int r852_wait(struct nand_chip *chip) static int r852_ready(struct nand_chip *chip) { struct r852_device *dev = r852_get_dev(nand_to_mtd(chip)); + if (dev->card_unstable) + return 0; + return !(r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_BUSY); }