[PATCH v2] ARM: dts: Add mask-tpm-reset to the device tree

Vikas Sajjan vikas.sajjan at samsung.com
Sun Jul 13 23:33:22 PDT 2014


From: Doug Anderson <dianders at chromium.org>

The mask-tpm-reset GPIO is used by the kernel to prevent the TPM from
being reset across sleep/wake.  If we don't set it to anything then
the TPM will be reset.  U-Boot will detect this as invalid
and will reset the system on resume time. This GPIO can always be low
and not hurt anything.  It will get pulled back high again during a
normal warm reset when it will default back to an input.

To properly preserve the TPM state across suspend/resume and to make
the chrome U-Boot happy, properly set the GPIO to mask the
reset to the TPM.

Signed-off-by: Doug Anderson <dianders at chromium.org>
Signed-off-by: Vikas Sajjan <vikas.sajjan at samsung.com>
---
changes since v1:
	- removed fixed regulator and used hogs instead.

 arch/arm/boot/dts/exynos5420-peach-pit.dts |   12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/arm/boot/dts/exynos5420-peach-pit.dts b/arch/arm/boot/dts/exynos5420-peach-pit.dts
index 6c7cab0..c036d9e 100644
--- a/arch/arm/boot/dts/exynos5420-peach-pit.dts
+++ b/arch/arm/boot/dts/exynos5420-peach-pit.dts
@@ -211,6 +211,18 @@
 
 
 &pinctrl_0 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&mask_tpm_reset>;
+
+	/* We need GPX0_6 to be low at sleep time; just keep it low always */
+	mask_tpm_reset: mask-tpm-reset {
+		samsung,pins = "gpx0-6";
+		samsung,pin-function = <1>;
+		samsung,pin-pud = <0>;
+		samsung,pin-drv = <0>;
+		samsung,pin-val = <0>;
+	};
+
 	max98090_irq: max98090-irq {
 		samsung,pins = "gpx0-2";
 		samsung,pin-function = <0>;
-- 
1.7.9.5




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