[PATCH] spi/imx: set the inactive state of the clock according to the clock polarity
From: Dirk Behme <hidden>
Date: 2012-08-31 08:55:11
Also in:
linux-spi
Subsystem:
spi subsystem, the rest · Maintainers:
Mark Brown, Linus Torvalds
From: Knut Wohlrab <redacted> There are SPI devices which need a SPI clock with active low polarity and high inactive state. Add the setting of the inactive state ECSPIx_CONFIGREG:SCLK CTL according to the clock polarity ECSPIx_CONFIGREG:SCLK POL: DT without "spi-cpol" = 0 = clock active high polarity = inactive state low DT with "spi-cpol" = 1 = clock active low polarity = inactive state high Signed-off-by: Knut Wohlrab <redacted> --- Question: Are there real world examples for a need of an individual setting of clock polarity/inactive state? drivers/spi/spi-imx.c | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index e834ff8..d64655b 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c@@ -197,6 +197,7 @@ static unsigned int spi_imx_clkdiv_2(unsigned int fin, #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_INT 0x10 #define MX51_ECSPI_INT_TEEN (1 << 0)
@@ -287,9 +288,10 @@ static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx, if (config->mode & SPI_CPHA) cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs); - if (config->mode & SPI_CPOL) + if (config->mode & SPI_CPOL) { cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs); - + cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs); + } if (config->mode & SPI_CS_HIGH) cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
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1.7.0.4