[U-Boot] [PATCH v1 16/16] board: Add Qualcomm Dragonboard 410C support

Simon Glass
2016-01-13T20:32:34Z

Hi Mateusz,

On 11 January 2016 at 15:01, Mateusz Kulikowski
<mateusz.kulikowski@gmail.com> wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA256
>
> Hi,
>
> On 11.01.2016 17:58, Simon Glass wrote:
>> Hi,
>>
>> On 6 January 2016 at 11:21, Mateusz Kulikowski
>> <mateusz.kulikowski@gmail.com> wrote:
>>> This commit add support for 96Boards Dragonboard410C.
> [...]
>>> + usb_hub_reset_n_pm {
>>> + gpios = <&pmic_gpios 2 0>;
>>> + };
>>> +
>>> + usb_sw_sel_pm {
>>> + gpios = <&pmic_gpios 3 0>;
>>> + };
>>> +
>>> + key_vol_down {
>>> + gpios = <&pmic_pon 1 0>;
>>> + };
>>> +
>>> + key_power {
>>> + gpios = <&pmic_pon 0 0>;
>>> + };
>>
>> The above four nodes seems odd in that they don't have compatible
>> strings. Is this how Linux does it? Also more normally the node name
>> has hyphens rather than underscores.
>
> In Linux nodes are childs of PMIC gpio periperhal (pmic_gpios in my case):
> &pm8916_gpios {
>
> usb_hub_reset_pm: usb_hub_reset_pm {
> pinconf {
> pins = "gpio3";
> function = PMIC_GPIO_FUNC_NORMAL;
> output-low;
> };
> };
>
> (https://github.com/torvalds/linux/blob/master/arch/arm64/boot/dts/qcom/apq8016-sbc-pmic-pins.dtsi)
>
> I decided to move them away from PMIC, as they only use specific gpios.
>
> To be honest they are just a references so I don't have to hardcode gpio names/numbers in
> board sources.
>
> Is it ok if I keep it that way? Could you suggest better approach?

We should avoid forking the device tree and making up bindings.

Really it looks like qcom,qpnp-pin should be a pinctrl driver. Then
pinctrl-0 in your device node will automatically pick up the correct
function.

Regards,
Simon