Recent VC4 firmware provides a hardware-independent way to retrieve the under-voltage sensor on the following Raspberry Pi boards: - Raspberry Pi B+ (via GPIO on SoC) - Raspberry Pi A+ (via GPIO on SoC) - Raspberry Pi 2 B (via GPIO on SoC) - Raspberry Pi 3 B (via GPIO on port expander) - Raspberry Pi 3 B+ (via PMIC) TODO: - try to make bcm2835 firmware a bus driver Signed-off-by: Stefan Wahren <stefan.wahren@xxxxxxxx> --- .../devicetree/bindings/hwmon/raspberrypi-hwmon.txt | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100644 Documentation/devicetree/bindings/hwmon/raspberrypi-hwmon.txt diff --git a/Documentation/devicetree/bindings/hwmon/raspberrypi-hwmon.txt b/Documentation/devicetree/bindings/hwmon/raspberrypi-hwmon.txt new file mode 100644 index 0000000..ec2523f --- /dev/null +++ b/Documentation/devicetree/bindings/hwmon/raspberrypi-hwmon.txt @@ -0,0 +1,19 @@ +Raspberry Pi voltage sensor +--------------------------- + +The VC4 firmware exposes a mailbox interface that allows the ARM core +to access the board's voltage sensor. + +Required properties : +- compatible : Should be "raspberrypi,bcm2835-hwmon" + +Example: + +firmware: firmware-rpi { + compatible = "raspberrypi,bcm2835-firmware"; + mboxes = <&mailbox>; + + voltage-sensor { + compatible = "raspberrypi,bcm2835-hwmon"; + }; +}; -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html