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

- From: Maxime Ripard \<hidden\>
- Date: 2021-07-22 08:16:26 
- List: linux-devicetree
- Page: https://ratatoskr.run/linux-devicetree/2021/07/8193203
- Thread: https://ratatoskr.run/linux-devicetree/2021/07/8193103/t.md

```text
On Thu, Jul 22, 2021 at 12:55:53AM -0500, Samuel Holland wrote:
> On 7/21/21 9:04 AM, Maxime Ripard wrote:
> > 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
```