Am Mittwoch, 11. Dezember 2024, 15:26:51 CET schrieb Sebastian Reichel: > Some power domains require extra voltages to be applied. For example > trying to enable the GPU power domain on RK3588 fails when the SoC > does not have VDD GPU enabled. The same is expected to happen for > the NPU, which also has a dedicated supply line. > > We get the regulator using devm_of_regulator_get(), so a missing > dependency in the devicetree is handled gracefully by printing a warning > and creating a dummy regulator. This is necessary, since existing DTs do > not have the regulator described. They might still work if the regulator > is marked as always-on. It is also working if the regulator is enabled > at boot time and the GPU driver is probed before the kernel disables > unused regulators. > > The regulator itself is not acquired at driver probe time, since that > creates an unsolvable circular dependency. The power domain driver must > be probed early, since SoC peripherals need it. Regulators on the other > hand depend on SoC peripherals like SPI, I2C or GPIO. MediaTek does not > run into this, since they have two power domain drivers. > > Tested-by: Heiko Stuebner <heiko@xxxxxxxxx> > Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx> Reviewed-by: Heiko Stuebner <heiko@xxxxxxxxx>
