[PATCH] ARM: dts: omap4-panda-es: Do not reset gpio1

Nishanth Menon nm at ti.com
Thu Oct 10 12:44:41 EDT 2013

Do not reset GPIO1 at boot-up because GPIO 7 in GPIO1 block is used on
OMAP4460 PandaBoard-ES to select voltage register in TPS62361 which
supplies VDD_MPU.

Without this, OMAP4460 PandaBoard-ES boards fail to boot-up because
MPU voltage switches over to VSET0 voltage value (boot voltage) which
is not sufficient to operate the device at OPP100.

Signed-off-by: Nishanth Menon <nm at ti.com>
As explained here: http://marc.info/?l=u-boot&m=133066647800872&w=2

GPIO1 reset causes PandaBoard-ES to stop functioning.
This depends on Patch series from Rajendra:
Applies on Benoit's for_13/dts branch:

Tested on PandaBoard-ES without the u-boot uenv hack

 arch/arm/boot/dts/omap4-panda-es.dts |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm/boot/dts/omap4-panda-es.dts b/arch/arm/boot/dts/omap4-panda-es.dts
index 56c4354..816d1c9 100644
--- a/arch/arm/boot/dts/omap4-panda-es.dts
+++ b/arch/arm/boot/dts/omap4-panda-es.dts
@@ -62,3 +62,7 @@
 		gpios = <&gpio1 8 GPIO_ACTIVE_HIGH>;
+&gpio1 {
+	 ti,no-reset-on-init;

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