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 5.4-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-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5cf86d335afe6e63edd0b0787df949394e9e27e0
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/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c
index 7bef63947b29f..97a5e1eaeefdf 100644
--- a/drivers/mtd/spi-nor/cadence-quadspi.c
+++ b/drivers/mtd/spi-nor/cadence-quadspi.c
@@ -475,7 +475,7 @@ static int cqspi_read_setup(struct spi_nor *nor)
/* Setup dummy clock cycles */
dummy_clk = nor->read_dummy;
if (dummy_clk > CQSPI_DUMMY_CLKS_MAX)
- dummy_clk = CQSPI_DUMMY_CLKS_MAX;
+ return -EOPNOTSUPP;
if (dummy_clk / 8) {
reg |= (1 << CQSPI_REG_RD_INSTR_MODE_EN_LSB);
