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spi: dw: Fix default polarity of native chipselect
authorLinus Walleij <linus.walleij@linaro.org>
Wed, 16 Jan 2019 08:21:08 +0000 (09:21 +0100)
committerMark Brown <broonie@kernel.org>
Thu, 24 Jan 2019 19:02:58 +0000 (19:02 +0000)
The DW controller also supports platforms specifying
native chipselects. When I enforce the use of high CS
for drivers opting in for using GPIO descriptors, I
inadvertedly switched the driver to also use active
high chip select for native chip selects.

As it turns out, the DW hardware driving chip selects
also thinks it is weird with active low chip selects
so all we need to do is remove an inversion in the
driver.

Cc: Jan Kotas <jank@cadence.com>
Reported-by: Jan Kotas <jank@cadence.com>
Tested-by: Jan Kotas <jank@cadence.com>
Fixes: 9400c41e77b8 ("spi: dw: Convert to use CS GPIO descriptors")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/spi-dw.c

index 7092e58..8abb942 100644 (file)
@@ -137,11 +137,10 @@ void dw_spi_set_cs(struct spi_device *spi, bool enable)
        struct dw_spi *dws = spi_controller_get_devdata(spi->controller);
        struct chip_data *chip = spi_get_ctldata(spi);
 
-       /* Chip select logic is inverted from spi_set_cs() */
        if (chip && chip->cs_control)
-               chip->cs_control(!enable);
+               chip->cs_control(enable);
 
-       if (!enable)
+       if (enable)
                dw_writel(dws, DW_SPI_SER, BIT(spi->chip_select));
        else if (dws->cs_override)
                dw_writel(dws, DW_SPI_SER, 0);