From: Kevin Groeneveld kgroeneveld@lenbrook.com
[ 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 --- drivers/spi/spi-imx.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-)
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index e4ccd0c329d06..c61c7ac4c70c4 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -252,6 +252,18 @@ 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) @@ -260,16 +272,16 @@ 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)