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spi: spi-imx: fix MX51_ECSPI_* macros when cs > 3

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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>
This commit is contained in:
Kevin Groeneveld 2023-03-18 18:21:32 -04:00 committed by Mark Brown
parent c2912d42e8
commit 87c614175b
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GPG key ID: 24D68B725D5487D0
1 changed files with 18 additions and 6 deletions
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24
drivers/spi/spi-imx.c
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@ -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)