[PATCH 2/2] arm64: allwinner: a64: bananapi-m64: add usb otg

Chen-Yu Tsai wens at csie.org
Wed Dec 6 23:01:04 PST 2017


On Thu, Dec 7, 2017 at 2:54 PM, Jagan Teki <jagannadh.teki at gmail.com> wrote:
> On Thu, Dec 7, 2017 at 11:56 AM, Chen-Yu Tsai <wens at csie.org> wrote:
>> On Thu, Dec 7, 2017 at 2:18 PM, Jagan Teki <jagannadh.teki at gmail.com> wrote:
>>> On Thu, Dec 7, 2017 at 8:54 AM, Chen-Yu Tsai <wens at csie.org> wrote:
>>>> On Thu, Dec 7, 2017 at 1:51 AM, Jagan Teki <jagannadh.teki at gmail.com> wrote:
>>>>> usb otg on bananapi-m64 has configured with USB-ID with PH9
>>>>> and USB-DRVVBUS attached with dcdc1 regulatort.
>>>>
>>>> That is not how you read the schematic...
>>>>
>>>> Intersecting lines that are tied together will have a dot representing
>>>> the connection. The DCDC1 line is a pull-up for the ID pin. This is very
>>>> clear because it has a resistor connected in series.
>>>>
>>>> VBUS for OTG is controlled by the IC displayed to the right in the
>>>> schematic, which is powered from 5V, and controlled by the DRVVBUS
>>>> pin from the PMIC. Please take a look at how the A31/A33/A83T board
>>>> dts files represent this.
>>>
>>> This is where I confused, USB-DRVVBUS is connected to pin 51 of PMIC
>>> if we add 5v regulator how can configure gpio number for this? I saw
>>
>> From the axp20x bindings:
>>
>> - x-powers,drive-vbus-en: boolean, set this when the N_VBUSEN pin is
>>                           used as an output pin to control an external
>>                           regulator to drive the OTG VBus, rather then
>>                           as an input pin which signals whether the
>>                           board is driving OTG VBus or not.
>>                           (axp221 / axp223 / axp813 only)
>>
>> Setting this allows you to use the "drivevbus" regulator under the PMIC.
>> As I said, look at how other boards are doing it.
>>
>>> sun8i-a33-olinuxino.dts which is also similar but it has gpio = <&pio
>>> 1 9 GPIO_ACTIVE_HIGH>;
>>
>> I have no idea where you saw this. It does not exist in my tree.
>>
>> Why don't you just trace backwards from the usb0_vbus-supply property
>> under the usbphy node, and see where it all leads.
>
> This what exactly I did, usb0_vbus-supply = <&reg_drivevbus>; on

This is not what you did in your patch.

> sun8i-a33-olinuxino.dts is using usb0-vbus from
> sunxi-common-regulators.dtsi. reg_usb0_vbus regulator using gpio9
> which I couldn't find it on schematics.

And I'm telling you that in mainline a33-olinuxino.dts it is:

    usb0_vbus-supply = <&reg_drivevbus>;

It has been that way since the initial commit adding the file.
What tree are you looking at exactly? Take a good look at everything,
including your patch, and stop arguing.

ChenYu



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