The fernsehfee3 board uses a Ricoh RN5T618 PMIC to generate various
voltages. Board schematics are not available, but the regulator voltages
found in /sys/kernel/debug/regulator/regulator_summary match those in
meson8m2-mxiii-plus.dts:
DCDC1 0 0 0 unknown 1100mV 0mA 0mV 0mV
DCDC2 0 0 0 unknown 1150mV 0mA 0mV 0mV
DCDC3 0 0 0 unknown 1500mV 0mA 0mV 0mV
LDO1 0 0 0 unknown 2900mV 0mA 0mV 0mV
LDO2 0 0 0 unknown 1800mV 0mA 0mV 0mV
LDO3 0 0 0 unknown 1800mV 0mA 0mV 0mV
LDO4 0 0 0 unknown 2850mV 0mA 0mV 0mV
LDO5 0 0 0 unknown 1800mV 0mA 0mV 0mV
LDORTC1 0 0 0 unknown 2700mV 0mA 0mV 0mV
LDORTC2 0 0 0 unknown 900mV 0mA 0mV 0mV
This patch takes the following approach:
- Copy RN5T618 regulator nodes from meson8m2-mxiii-plus.dts
- Remove some of the regulator names, which do not seem to apply
- Verify regulator supply relations by starting without any relations
(and without regulator-always-on) and seeing what breaks when the
kernel turns off "unused" regulators.
This results in the following observations:
- When LDO1 is turned off, the board resets
- When DCDC1, DCDC2, DCDC3, LDO2, or LDO5 are turned off, the board (as
observed through the serial port) stops running, so these must stay on
at all times.
- LDO4 (VCC2V8) appears to be unused on this board.
- LDO3 (VCC1V8_USB) must stay on in order for USB to work, both the
external USB ports and the internal USB wifi module.
The cpu-supply and mali-supply relations are also copied from
meson8m2-mxiii-plus.dts
Signed-off-by: J. Neuschäfer <j.ne@posteo.net>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20250428-fernsehfee-v2-4-293b98a43a91@posteo.net
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Fernsehfee[1] ("TV fairy") 3.0 is a set-top box with HDMI input and
output ports. It originally ran Android 4.4 and a Linux 3.10 kernel.
The following features are tested and known to work:
- Ethernet
- Power LED (switching between green and red)
- Power button
- eMMC
- SD Card
- USB
- Wifi
The following features are untested or not working:
- HDMI input and output
- Infrared remote control input and output
[1]: https://fernsehfee.de/ (German), https://telefairy.com/ (English)
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: J. Neuschäfer <j.ne@posteo.net>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20250428-fernsehfee-v2-3-293b98a43a91@posteo.net
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
