of: Rename "poweroff-source" property to "system-power-controller"

It reverts commit a4b4e0461ec5 ("of: Add standard property for poweroff capability").
As discussed on the mailing list, it makes more sense to rename back to the
old established property name, without the vendor prefix. Problem being that
the word "source" usually tends to be used for inputs and that is out of control
of the OS. The poweroff capability is an output which simply turns the
system-power off. Also, this property might be used by drivers which power-off
the system and power back on subsequent RTC alarms. This seems to suggest to
remove "poweroff" from the property name and to choose "system-power-controller"
as the more generic name. This patchs adds the required renaming changes and
defines an helper function which checks if this property is set.

Signed-off-by: Romain Perier <romain.perier@gmail.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 18 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/power/power-controller.txt b/Documentation/devicetree/bindings/power/power-controller.txt
new file mode 100644
index 000000000000..845868bf3273
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/power-controller.txt
@@ -0,0 +1,18 @@
+* Generic Poweroff capability
+
+Power-management integrated circuits or miscellaneous harware components are
+sometimes able to control the system power. The device driver associated to these
+components might needs to define poweroff capability, which tells to the kernel
+how to switch off the system. The corresponding driver must have the standard
+property "poweroff-source" in its device node. This property marks the device as
+able to shutdown the system. In order to test if this property is found
+programmatically, use the helper function "of_system_has_poweroff_source" from
+of.h .
+
+Example:
+
+act8846: act8846@5 {
+	 compatible = "active-semi,act8846";
+	 status = "okay";
+	 poweroff-source;
+}