From 2dd73db1b508810288131ff63d4f2f5f63c216fc Mon Sep 17 00:00:00 2001
From: Pratyush Yadav
Date: Wed, 23 Dec 2020 00:14:20 +0530
Subject: [PATCH] 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
Link: https://lore.kernel.org/r/20201222184425.7028-3-p.yadav@ti.com
Signed-off-by: Mark Brown
Signed-off-by: Sasha Levin
---
drivers/mtd/spi-nor/cadence-quadspi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c
index 7bef63947b29..97a5e1eaeefd 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);