Re: [PATCH 52/54] arm64: dts: allwinner: Remove regulator-ramp-delay

On Thu, Jul 22, 2021 at 12:55:53AM -0500, Samuel Holland wrote:

On 7/21/21 9:04 AM, Maxime Ripard wrote:

quoted

The regulator-ramp-delay property isn't documented in the binding for
the AXP806, and it's ignored by the driver. Remove those properties.

This is a generic regulator property, parsed by
of_get_regulation_constraints, which is called by
regulator_of_get_init_data in the regulator core. And it appears in
bindings/regulator/regulator.yaml. I believe the binding needs to be
fixed, not the device trees.

It's indeed parsed by the regulator framework, but then it calls into
the driver if that property is set using set_ramp_delay if it's set.

https://elixir.bootlin.com/linux/latest/source/drivers/regulator/core.c#L1378

We don't set that hook for the AXP806 DCDC-A and DCDC-E regulators (that
use AXP_DESC_RANGES) at all:

https://elixir.bootlin.com/linux/latest/source/drivers/regulator/axp20x-regulator.c#L343

And the only implementation we have (set for AXP_DESC and AXP_DESC_IO)
works only for the AXP209:

https://elixir.bootlin.com/linux/latest/source/drivers/regulator/axp20x-regulator.c#L368

So, it just looks like those properties have never been tested since
they were just ignored.

Maxime