lkml.org 
[lkml]   [2014]   [Oct]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 6/8] regulator: max77686: Add external GPIO control
[adding Linus and Alexandre to the cc list]

Hello Krzysztof,

On 10/29/2014 11:42 AM, Krzysztof Kozlowski wrote:
> On wto, 2014-10-28 at 13:11 +0100, Krzysztof Kozlowski wrote:
>> On wto, 2014-10-28 at 09:52 +0100, Krzysztof Kozlowski wrote:
>> > On pon, 2014-10-27 at 21:03 +0100, Javier Martinez Canillas wrote:
>> > > Hello Krzysztof,
>> > >
>> > > On 10/27/2014 04:03 PM, Krzysztof Kozlowski wrote:
>> > > > @@ -85,6 +91,9 @@ struct max77686_data {
>> > > > struct max77686_regulator_data *regulators;
>> > > > int num_regulators;
>> > > >
>> > > > + /* Array of size num_regulators with GPIOs for external control. */
>> > > > + int *ext_control_gpio;
>> > > > +
>> > >
>> > > The integer-based GPIO API is deprecated in favor of the descriptor-based GPIO
>> > > interface (Documentation/gpio/consumer.txt). Could you please use the later?
>> >
>> > Sure, I can. Please have in mind that regulator core still accepts old
>> > GPIO so I will have to use desc_to_gpio(). That should work... and
>> > should be future-ready.
>>
>> It seems I was too hasty... I think usage of the new gpiod API implies
>> completely different bindings.
>>
>> The gpiod_get() gets GPIO from a device level, not from given sub-node
>> pointer. This means that you cannot have DTS like this:
>> ldo21_reg: ldo21 {
>> regulator-compatible = "LDO21";
>> regulator-name = "VTF_2.8V";
>> regulator-min-microvolt = <2800000>;
>> regulator-max-microvolt = <2800000>;
>> ec-gpio = <&gpy2 0 0>;
>> };
>>
>> ldo22_reg: ldo22 {
>> regulator-compatible = "LDO22";
>> regulator-name = "VMEM_VDD_2.8V";
>> regulator-min-microvolt = <2800000>;
>> regulator-max-microvolt = <2800000>;
>> ec-gpio = <&gpk0 2 0>;
>> };
>>
>>
>> I could put GPIOs in device node:
>>
>> max77686_pmic@09 {
>> compatible = "maxim,max77686";
>> interrupt-parent = <&gpx0>;
>> interrupts = <7 0>;
>> reg = <0x09>;
>> #clock-cells = <1>;
>> ldo21-gpio = <&gpy2 0 0>;
>> ldo22-gpio = <&gpk0 2 0>;
>>
>> ldo21_reg: ldo21 {
>> regulator-compatible = "LDO21";
>> regulator-name = "VTF_2.8V";
>> regulator-min-microvolt = <2800000>;
>> regulator-max-microvolt = <2800000>;
>> };
>>
>> ldo22_reg: ldo22 {
>> regulator-compatible = "LDO22";
>> regulator-name = "VMEM_VDD_2.8V";
>> regulator-min-microvolt = <2800000>;
>> regulator-max-microvolt = <2800000>;
>> };
>>
>> This would work but I don't like it. The properties of a regulator are
>> above the node configuring that regulator.
>>
>> Any ideas?
>>
>
> Continuing talking to myself... I found another problem - GPIO cannot be
> requested more than once (-EBUSY). In case of this driver (and board:
> Trats2) one GPIO is connected to regulators. The legacy GPIO API and
> regulator core handle this.
>
> With new GPIO API I would have to implement some additional steps in
> such case...
>
> So there are 2 issues:
> 1. Cannot put GPIO property in regulator node.
> 2. Cannot request some GPIO more than once.
>
> I'm going back to legacy API for now.
>

I've added the GPIO maintainers as cc so hopefully they can comment on this.

> Best regards,
> Krzysztof
>

Best regards,
Javier


\
 
 \ /
  Last update: 2014-10-29 12:01    [W:0.100 / U:0.340 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site