ARM: dts: dir685: Drop spi-cpol from the display
authorLinus Walleij <linus.walleij@linaro.org>
Sun, 15 Sep 2019 13:54:44 +0000 (15:54 +0200)
committerArnd Bergmann <arnd@arndb.de>
Mon, 16 Sep 2019 14:31:17 +0000 (16:31 +0200)
The D-Link DIR-685 had its clock polarity set as active
low using the special SPI "spi-cpol" property.

This is not correct: the datasheet clearly states:
"Fix SCL to GND level when not in use" which is
indicative that this line is active high.

After a recent fix making the GPIO-based SPI driver
force the clock line de-asserted at the beginning of
each SPI transaction this reared its ugly head: now
de-asserted was taken to mean the line should be
driven high, but it should be driven low.

Fix this up in the DTS file and the display works again.

Link: https://lore.kernel.org/r/20190915135444.11066-1-linus.walleij@linaro.org
Cc: Mark Brown <broonie@kernel.org>
Fixes: 2922d1cc1696 ("spi: gpio: Add SPI_MASTER_GPIO_SS flag")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
arch/arm/boot/dts/gemini-dlink-dir-685.dts

index bfaa2de63a1001e7aec1ca5154b47f60983dad1c..e2030ba16512f52c927e0b53a2fca54b9a613490 100644 (file)
@@ -72,7 +72,6 @@
                        reg = <0>;
                        /* 50 ns min period = 20 MHz */
                        spi-max-frequency = <20000000>;
-                       spi-cpol; /* Clock active low */
                        vcc-supply = <&vdisp>;
                        iovcc-supply = <&vdisp>;
                        vci-supply = <&vdisp>;