Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1419263

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

Show all headers | View raw

On 10/06/16 13:44, Sergei Shtylyov wrote:
> On 6/10/2016 1:19 PM, 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@ti.com>
>>>
>>
>> <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?
> 
>    No.
> 
>> What is wrong with calling it gadget controller?
> 
>    It's not a controller, it's a piece of software AFAIU. Or is my English just too weak? :-)

Everything at this point is a piece of software :).

struct usb_gadget, represents the gadget controller device not the driver (or software).

struct usb_gadget_driver represents the gadget function driver.
struct usb_gadget_ops represents the UDC driver ops.

--
cheers,
-roger

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v9 00/14] USB OTG/dual-role framework Roger Quadros <rogerq@ti.com> - 2016-06-08 11:10 +0200
  [PATCH v9 10/14] usb: otg: add hcd companion support Roger Quadros <rogerq@ti.com> - 2016-06-08 11:10 +0200
  [PATCH v9 11/14] usb: otg: use dev_dbg() instead of VDBG() Roger Quadros <rogerq@ti.com> - 2016-06-08 11:10 +0200
    Re: [PATCH v9 11/14] usb: otg: use dev_dbg() instead of VDBG() Joe Perches <joe@perches.com> - 2016-06-08 17:20 +0200
      Re: [PATCH v9 11/14] usb: otg: use dev_dbg() instead of VDBG() Roger Quadros <rogerq@ti.com> - 2016-06-09 09:30 +0200
    [PATCH v10 11/14] usb: otg: use dev_dbg() instead of VDBG() Roger Quadros <rogerq@ti.com> - 2016-06-09 10:00 +0200
      Re: [PATCH v10 11/14] usb: otg: use dev_dbg() instead of VDBG() Joe Perches <joe@perches.com> - 2016-06-09 17:50 +0200
        Re: [PATCH v10 11/14] usb: otg: use dev_dbg() instead of VDBG() Roger Quadros <rogerq@ti.com> - 2016-06-10 09:10 +0200
  [PATCH v9 02/14] usb: otg-fsm: Prevent build warning "VDBG" redefined Roger Quadros <rogerq@ti.com> - 2016-06-08 11:10 +0200
  [PATCH v9 09/14] usb: of: add an API to get OTG device from USB controller node Roger Quadros <rogerq@ti.com> - 2016-06-08 11:10 +0200
  [PATCH v9 14/14] usb: host: xhci-plat: Add otg device to platform data Roger Quadros <rogerq@ti.com> - 2016-06-08 11:10 +0200
  [PATCH v9 08/14] usb: otg: add OTG/dual-role core Roger Quadros <rogerq@ti.com> - 2016-06-08 11:10 +0200
    Re: [PATCH v9 08/14] usb: otg: add OTG/dual-role core Peter Chen <hzpeterchen@gmail.com> - 2016-06-08 12:00 +0200
      Re: [PATCH v9 08/14] usb: otg: add OTG/dual-role core Roger Quadros <rogerq@ti.com> - 2016-06-08 12:20 +0200
        Re: [PATCH v9 08/14] usb: otg: add OTG/dual-role core Peter Chen <hzpeterchen@gmail.com> - 2016-06-08 14:50 +0200
          Re: [PATCH v9 08/14] usb: otg: add OTG/dual-role core Roger Quadros <rogerq@ti.com> - 2016-06-09 09:30 +0200
    [PATCH v10 08/14] usb: otg: add OTG/dual-role core Roger Quadros <rogerq@ti.com> - 2016-06-09 10:00 +0200
      Re: [PATCH v10 08/14] usb: otg: add OTG/dual-role core Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> - 2016-06-09 14:40 +0200
        Re: [PATCH v10 08/14] usb: otg: add OTG/dual-role core Roger Quadros <rogerq@ti.com> - 2016-06-10 09:10 +0200
        Re: [PATCH v10 08/14] usb: otg: add OTG/dual-role core Roger Quadros <rogerq@ti.com> - 2016-06-10 12:20 +0200
          Re: [PATCH v10 08/14] usb: otg: add OTG/dual-role core Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> - 2016-06-10 12:50 +0200
            Re: [PATCH v10 08/14] usb: otg: add OTG/dual-role core Roger Quadros <rogerq@ti.com> - 2016-06-10 13:00 +0200
              Re: [PATCH v10 08/14] usb: otg: add OTG/dual-role core Felipe Balbi <balbi@kernel.org> - 2016-06-10 13:10 +0200
  [PATCH v9 13/14] usb: gadget: udc: adapt to OTG core Roger Quadros <rogerq@ti.com> - 2016-06-08 11:10 +0200
    RE: [PATCH v9 13/14] usb: gadget: udc: adapt to OTG core Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> - 2016-06-09 12:50 +0200
      Re: [PATCH v9 13/14] usb: gadget: udc: adapt to OTG core Roger Quadros <rogerq@ti.com> - 2016-06-10 09:10 +0200
  [PATCH v9 07/14] usb: otg: get rid of CONFIG_USB_OTG_FSM in favour of CONFIG_USB_OTG Roger Quadros <rogerq@ti.com> - 2016-06-08 11:20 +0200
  [PATCH v9 01/14] usb: hcd: Initialize hcd->flags to 0 Roger Quadros <rogerq@ti.com> - 2016-06-08 11:20 +0200
  [PATCH v9 05/14] usb: otg-fsm: move host controller operations into usb_otg->hcd_ops Roger Quadros <rogerq@ti.com> - 2016-06-08 11:20 +0200
  [PATCH v9 06/14] usb: gadget.h: Add OTG to gadget interface Roger Quadros <rogerq@ti.com> - 2016-06-08 11:20 +0200
  Re: [PATCH v9 00/14] USB OTG/dual-role framework Peter Chen <hzpeterchen@gmail.com> - 2016-06-09 07:30 +0200
    Re: [PATCH v9 00/14] USB OTG/dual-role framework Roger Quadros <rogerq@ti.com> - 2016-06-09 09:40 +0200
      RE: [PATCH v9 00/14] USB OTG/dual-role framework Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> - 2016-06-09 12:20 +0200

csiph-web