[PATCH 1/4] USB: Fix of_usb_get_dr_mode_by_phy with a shared phy block

Hans de Goede hdegoede at redhat.com
Fri Jun 3 06:09:00 PDT 2016


Hi,

On 03-06-16 15:04, Bin Liu wrote:
> Hi,
>
> On Fri, Jun 03, 2016 at 12:34:35PM +0200, Hans de Goede wrote:
>> Hi,
>>
>> On 02-06-16 20:16, Bin Liu wrote:
>>> Hi,
>>>
>>> On Thu, Jun 02, 2016 at 07:31:03PM +0200, Hans de Goede wrote:
>>>> Some SoCs have a single phy-hw-block with multiple phys, this is
>>>> modelled by a single phy dts node, so we end up with multiple
>>>> controller nodes with a phys property pointing to the phy-node
>>>> of the otg-phy.
>>>>
>>>> Only one of these controllers typically is an otg controller, yet we
>>>
>>> Is it guaranteed that only one of them will be otg?
>>
>> I guess not, but if there are 2 then with my patch we are of no worse
>> then today, we will then pick the first otg controller. Whereas
>
> What if the first otg controller is not what we want? this patch does
> not solve the problem. I would think Kishon's suggestion in another
> email - seperate dt phy nodes - is a better option.

That is not possible as it will break the dt-bindings for existing
devices.

And that adds a lot of complexity without a good reason, as I mentioned
in my reply to Kishon if we want to make 100% sure that we've the
right controller, we should pass in the phy index argument to the
phandle to of_usb_get_dr_mode_by_phy and make of_usb_get_dr_mode_by_phy
check this.

I'll submit a v2 which does this.

Regards,

Hans



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