From fa9463564e77067df81b0b8dec91adbbbc47bfb4 Mon Sep 17 00:00:00 2001
From: Linus Walleij <linus.walleij@linaro.org>
Date: Mon, 18 Mar 2019 16:31:22 +0100
Subject: [PATCH] ARM: dts: nomadik: Fix polarity of SPI CS
The SPI DT bindings are for historical reasons a pitfall,
the ability to flag a GPIO line as active high/low with
the second cell flags was introduced later so the SPI
subsystem will only accept the bool flag spi-cs-high
to indicate that the line is active high.
It worked by mistake, but the mistake was corrected
in another commit.
The comment in the DTS file was also misleading: this
CS is indeed active high.
Fixes: cffbb02dafa3 ("ARM: dts: nomadik: Augment NHK15 panel setting")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
arch/arm/boot/dts/ste-nomadik-nhk15.dts | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/arch/arm/boot/dts/ste-nomadik-nhk15.dts b/arch/arm/boot/dts/ste-nomadik-nhk15.dts
index 04066f9cb8a31..f2f6558a00f18 100644
--- a/arch/arm/boot/dts/ste-nomadik-nhk15.dts
+++ b/arch/arm/boot/dts/ste-nomadik-nhk15.dts
@@ -213,12 +213,13 @@ spi {
gpio-sck = <&gpio0 5 GPIO_ACTIVE_HIGH>;
gpio-mosi = <&gpio0 4 GPIO_ACTIVE_HIGH>;
/*
- * It's not actually active high, but the frameworks assume
- * the polarity of the passed-in GPIO is "normal" (active
- * high) then actively drives the line low to select the
- * chip.
+ * This chipselect is active high. Just setting the flags
+ * to GPIO_ACTIVE_HIGH is not enough for the SPI DT bindings,
+ * it will be ignored, only the special "spi-cs-high" flag
+ * really counts.
*/
cs-gpios = <&gpio0 6 GPIO_ACTIVE_HIGH>;
+ spi-cs-high;
num-chipselects = <1>;
/*
--
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