This is a note to let you know that I've just added the patch titled spi: cadence-quadspi: Abort read if dummy cycles required are too many to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: spi-cadence-quadspi-abort-read-if-dummy-cycles-requi.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit bf25753dac0ebfeedfa662f376c7824edc73ae4e Author: Pratyush Yadav <p.yadav@xxxxxx> Date: Wed Dec 23 00:14:20 2020 +0530 spi: cadence-quadspi: Abort read if dummy cycles required are too many [ Upstream commit ceeda328edeeeeac7579e9dbf0610785a3b83d39 ] The controller can only support up to 31 dummy cycles. If the command requires more it falls back to using 31. This command is likely to fail because the correct number of cycles are not waited upon. Rather than silently issuing an incorrect command, fail loudly so the caller can get a chance to find out the command can't be supported by the controller. Fixes: 140623410536 ("mtd: spi-nor: Add driver for Cadence Quad SPI Flash Controller") Signed-off-by: Pratyush Yadav <p.yadav@xxxxxx> Link: https://lore.kernel.org/r/20201222184425.7028-3-p.yadav@xxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c index ba7d40c2922f7..826b01f346246 100644 --- a/drivers/spi/spi-cadence-quadspi.c +++ b/drivers/spi/spi-cadence-quadspi.c @@ -461,7 +461,7 @@ static int cqspi_read_setup(struct cqspi_flash_pdata *f_pdata, /* Setup dummy clock cycles */ dummy_clk = op->dummy.nbytes * 8; if (dummy_clk > CQSPI_DUMMY_CLKS_MAX) - dummy_clk = CQSPI_DUMMY_CLKS_MAX; + return -EOPNOTSUPP; if (dummy_clk) reg |= (dummy_clk & CQSPI_REG_RD_INSTR_DUMMY_MASK)