Re: [PATCH v10 08/14] usb: otg: add OTG/dual-role core

[Roger Quadros]

Hi,

On 09/06/16 15:34, Sergei Shtylyov wrote:
> On 6/9/2016 10:53 AM, Roger Quadros wrote:
> 
>> It provides APIs for the following tasks
>>
>> - Registering an OTG/dual-role capable controller
>> - Registering Host and Gadget controllers to OTG core
>> - Providing inputs to and kicking the OTG state machine
>>
>> Provide a dual-role device (DRD) state machine.
>> DRD mode is a reduced functionality OTG mode. In this mode
>> we don't support SRP, HNP and dynamic role-swap.
>>
>> In DRD operation, the controller mode (Host or Peripheral)
>> is decided based on the ID pin status. Once a cable plug (Type-A
>> or Type-B) is attached the controller selects the state
>> and doesn't change till the cable in unplugged and a different
>> cable type is inserted.
>>
>> As we don't need most of the complex OTG states and OTG timers
>> we implement a lean DRD state machine in usb-otg.c.
>> The DRD state machine is only interested in 2 hardware inputs
>> 'id' and 'b_sess_vld'.
>>
>> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> 

<snip>

> [...]
>> +/**
>> + * usb_otg_register_gadget - Register the gadget controller to OTG core
>> + * @gadget:    gadget controller
> 
>    We call that USB device controller (UDC). I'm not sure what you meant here...
>    And what about the 2nd arg, 'ops'?

There are 2 data structures representing the Device controller.

struct usb_gadget - represents a usb slave device
struct usb_udc -struct usb_udc - describes one usb device controller

usb_udc is for private use only. usb_otg_register_gadget() takes struct usb_gadget
as argument.

Do you want me to refer to struct usb_gadget as UDC?

What is wrong with calling it gadget controller?

--
cheers,
-roger