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authorKevin Groeneveld2023-03-18 18:21:32 -0400
committerGreg Kroah-Hartman2023-05-24 17:32:40 +0100
commitb484aa214763544a76c183b6fc9548ef7a03bff1 (patch)
treeb92b01c0def1a2f38fa0c27b6105cd372098346c /drivers/spi
parent1844749dcfc486513d13e88933d4c80fca99a288 (diff)
spi: spi-imx: fix MX51_ECSPI_* macros when cs > 3
[ Upstream commit 87c614175bbf28d3fd076dc2d166bac759e41427 ] When using gpio based chip select the cs value can go outside the range 0 – 3. The various MX51_ECSPI_* macros did not take this into consideration resulting in possible corruption of the configuration. For example for any cs value over 3 the SCLKPHA bits would not be set and other values in the register possibly corrupted. One way to fix this is to just mask the cs bits to 2 bits. This still allows all 4 native chip selects to work as well as gpio chip selects (which can use any of the 4 chip select configurations). Signed-off-by: Kevin Groeneveld <kgroeneveld@lenbrook.com> Link: https://lore.kernel.org/r/20230318222132.3373-1-kgroeneveld@lenbrook.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/spi-imx.c24
1 files changed, 18 insertions, 6 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index fbd7b354dd36..2c660a95c17e 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -253,6 +253,18 @@ static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device
return true;
}
+/*
+ * Note the number of natively supported chip selects for MX51 is 4. Some
+ * devices may have less actual SS pins but the register map supports 4. When
+ * using gpio chip selects the cs values passed into the macros below can go
+ * outside the range 0 - 3. We therefore need to limit the cs value to avoid
+ * corrupting bits outside the allocated locations.
+ *
+ * The simplest way to do this is to just mask the cs bits to 2 bits. This
+ * still allows all 4 native chip selects to work as well as gpio chip selects
+ * (which can use any of the 4 chip select configurations).
+ */
+
#define MX51_ECSPI_CTRL 0x08
#define MX51_ECSPI_CTRL_ENABLE (1 << 0)
#define MX51_ECSPI_CTRL_XCH (1 << 2)
@@ -261,16 +273,16 @@ static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device
#define MX51_ECSPI_CTRL_DRCTL(drctl) ((drctl) << 16)
#define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8
#define MX51_ECSPI_CTRL_PREDIV_OFFSET 12
-#define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18)
+#define MX51_ECSPI_CTRL_CS(cs) ((cs & 3) << 18)
#define MX51_ECSPI_CTRL_BL_OFFSET 20
#define MX51_ECSPI_CTRL_BL_MASK (0xfff << 20)
#define MX51_ECSPI_CONFIG 0x0c
-#define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0))
-#define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs) + 4))
-#define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs) + 8))
-#define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs) + 12))
-#define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs) + 20))
+#define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs & 3) + 0))
+#define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs & 3) + 4))
+#define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs & 3) + 8))
+#define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs & 3) + 12))
+#define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs & 3) + 20))
#define MX51_ECSPI_INT 0x10
#define MX51_ECSPI_INT_TEEN (1 << 0)