From 7a6cb0abe1aa63334f3ded6d2b6c8eca80e72302 Mon Sep 17 00:00:00 2001 From: Matthijs van Duin Date: Mon, 1 Jun 2015 21:33:28 +0200 Subject: [PATCH] ARM: dts: am335x-boneblack: disable RTC-only sleep to avoid hardware damage Avoid entering "RTC-only mode" at poweroff. It is unsupported by most versions of BeagleBone, and risks hardware damage. The damaging configuration is having system-power-controller without ti,pmic-shutdown-controller. Reported-by: Matthijs van Duin Tested-by: Matthijs van Duin Signed-off-by: Robert Nelson Cc: Tony Lindgren Cc: Felipe Balbi Cc: Johan Hovold [Matthijs van Duin: added explanatory comments] Signed-off-by: Matthijs van Duin Fixes: http://bugs.elinux.org/issues/143 Cc: stable@vger.kernel.org # v3.12+ [tony@atomide.com: updated comments with the hardware breaking info] Signed-off-by: Tony Lindgren --- arch/arm/boot/dts/am335x-bone-common.dtsi | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/arch/arm/boot/dts/am335x-bone-common.dtsi b/arch/arm/boot/dts/am335x-bone-common.dtsi index c3255e0..dbb3f4d 100644 --- a/arch/arm/boot/dts/am335x-bone-common.dtsi +++ b/arch/arm/boot/dts/am335x-bone-common.dtsi @@ -223,6 +223,25 @@ /include/ "tps65217.dtsi" &tps { + /* + * Configure pmic to enter OFF-state instead of SLEEP-state ("RTC-only + * mode") at poweroff. Most BeagleBone versions do not support RTC-only + * mode and risk hardware damage if this mode is entered. + * + * For details, see linux-omap mailing list May 2015 thread + * [PATCH] ARM: dts: am335x-bone* enable pmic-shutdown-controller + * In particular, messages: + * http://www.spinics.net/lists/linux-omap/msg118585.html + * http://www.spinics.net/lists/linux-omap/msg118615.html + * + * You can override this later with + * &tps { /delete-property/ ti,pmic-shutdown-controller; } + * if you want to use RTC-only mode and made sure you are not affected + * by the hardware problems. (Tip: double-check by performing a current + * measurement after shutdown: it should be less than 1 mA.) + */ + ti,pmic-shutdown-controller; + regulators { dcdc1_reg: regulator@0 { regulator-name = "vdds_dpr"; -- 2.7.4