spi: dw: Fix default polarity of native chipselect

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: NJan Kotas <jank@cadence.com>
Tested-by: NJan Kotas <jank@cadence.com>
Fixes: 9400c41e ("spi: dw: Convert to use CS GPIO descriptors")
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

drivers/spi/spi-dw.c

@@ -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);