[linux-sunxi] [PATCH] musb: sunxi: Ignore VBus errors in host-only mode

Hans de Goede
2015-09-10T18:38:38Z

Hi,

On 10-09-15 20:30, Maxime Ripard wrote:
> On Thu, Sep 10, 2015 at 08:23:23PM +0200, Hans de Goede wrote:
>> Hi,
>>
>> On 04-09-15 08:43, Olliver Schinagl wrote:
>>> Hey Hans,
>>>
>>> On 07-08-15 10:45, Olliver Schinagl wrote:
>>>> <snip>
>>>>> If you change the dr_mode to host then you _must_ also remove any id_det and vbus_det
>>>>> gpio settings from the usb_phy node in the dts, as the sun4i phy code detects
>>>>> host vs otg mode by checking for the presence of these.
>>>> Yes, this fixes it and makes it work. Thanks.
>>>>
>>> I've been going back to this and am wondering if this is something I can look into to fix properly? E.g. if the dts sets dr_mode = host, can we simply ignore the pins and treat them as unset?
>>
>> AFAIK you cannot unset something in dts. The only solution I
>> can comeup with is to add a dr_mode argument to the phy like
>> we already have for the otg controller itself.
>>
>> This is something which we likely need to do anyways to add
>> support for peripheral only mode, which we seem to need for
>> some "hdmi sticks".
>
> I haven't really followed the rest of the discussion, so sorry if you
> already talked about that, but why can't you just set the dr_mode to
> peripheral in such a case?

This is about the usbphy code not the musb-controller code, which are
2 different dts nodes, atm only the musb-controller node has a
dr_mode property, and the phy code decides between host-only
and otg mode based on whether an id pin is assigned or not.

My proposal is to get rid of the id-pin hack to determine the mode
and add a dr_mode property to the usbphy dts node.

Regards,

Hans