Re: [PATCH v8 10/14] usb: otg: add hcd companion support

From: Roger Quadros
Date: Mon May 16 2016 - 04:12:50 EST


On 13/05/16 21:13, Rob Herring wrote:
> On Fri, May 13, 2016 at 5:03 AM, Roger Quadros <rogerq@xxxxxx> wrote:
>> From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
>>
>> Since some host controller (e.g. EHCI) needs a companion host controller
>> (e.g. OHCI), this patch adds such a configuration to use it in the OTG
>> core.
>>
>> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
>> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
>> Acked-by: Peter Chen <peter.chen@xxxxxxx>
>> ---
>> Documentation/devicetree/bindings/usb/generic.txt | 3 +++
>> drivers/usb/common/usb-otg.c | 32 ++++++++++++++++-------
>> include/linux/usb/otg.h | 7 ++++-
>> 3 files changed, 32 insertions(+), 10 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/generic.txt b/Documentation/devicetree/bindings/usb/generic.txt
>> index f6866c1..1db1c33 100644
>> --- a/Documentation/devicetree/bindings/usb/generic.txt
>> +++ b/Documentation/devicetree/bindings/usb/generic.txt
>> @@ -27,6 +27,9 @@ Optional properties:
>> - otg-controller: phandle to otg controller. Host or gadget controllers can
>> contain this property to link it to a particular OTG
>> controller.
>> + - hcd-needs-companion: must be present if otg controller is dealing with
>> + EHCI host controller that needs a companion OHCI host
>> + controller.
>
> I thought the conclusion was this is not needed?

This is still needed to differentiate between primary+shared HCD case vs
primary + primary-companion HCD case.

>
> One thing that is not clear here is otg-controller is a host or device
> property while hcd-needs-companion is an OTG controller property.
> These lists should be separated.

Agreed. I'll fix that up.

cheers,
-roger