Re: [v3 PATCH 1/5] extcon: Add Type-C and DP support

[Chanwoo Choi <cwchoi00@gmail.com>]

Hi Guenter,

2016-07-07 5:22 GMT+09:00 Guenter Roeck <groeck@google.com>:
> Hi,
>
> On Tue, Jun 28, 2016 at 6:40 PM, Chanwoo Choi <cwchoi00@gmail.com> wrote:
>> Hi Guenter,
>>
>> 2016년 6월 29일 수요일, Guenter Roeck<groeck@google.com>님이 작성한 메시지:
>>>
>>> On Tue, Jun 28, 2016 at 5:26 AM, Chanwoo Choi <cwchoi00@gmail.com> wrote:
>>> > Hi Chris,
>>> >
>>> > I agree to add the new EXTCON_DISP_DP connector.
>>> > But, other new definition should be discussed.
>>> > - EXTCON_DISP_DP_ALT
>>> > - EXTCON_TYPEC_POLARITY
>>> > - EXTCON_TYPEC_PIN_ASSIGN
>>> >
>>> > I think that TYPEC_POLARITY and TYPEC_PIN_ASSING are not appropriate
>>> > as the new external connector definition. These are the property or
>>> > attribute of
>>> > USB connector with C-type.
>>> >
>>> > Also, EXTCON_DISP_DP_ALT is not a new type of connector.
>>> > It is just one of the mode for DP connector.
>>> >
>>> > As I knew, DP alternative mode use the USB connector with C-type.
>>> > So, DP alternative mode can be expressed on following:
>>> >  = EXTCON_DISP_DP + EXTCON_USB + some property of USB c-type
>>> >
>>>
>>> Problem is that extcon doesn't support exchanging cable properties
>>> between cable providers (extcon drivers) and consumers, other than
>>> cable states. In order to exchange properties such as polarity and pin
>>> assignments, we would need a separate infrastructure. But then the
>>> question would be why to use extcon in the first place.
>>>
>>> If you have a solution for that puzzle, please let us know.
>>>
>>
>> You're right.
>> Current extcon don't support the cable properties.
>> The requirement about cables properties occur such as USB ID and VBUS pin.
>> So, I'll support the cable properties in extcon framework and send the
>> patches within this week.
>>
>
> Did you have time to look into this ? Any idea if/when you will send
> the patches ?

Firstly, I'm sorry for late reply.

I'm developing the suggested idea on extcon-test branch[1]. But, I
have not yet completed.
There are issues about compatibility of existing notifier of extcon.

It[1] is not final version. I need more time to make the well design
for extcon property.

[1] https://git.kernel.org/cgit/linux/kernel/git/chanwoo/extcon.git/log/?h=extcon-test
- usb: dwc3: omap: Support the changed method to get the state of connector
- usb: chipdata: Support the changed method to get the state of connector
- extcon: Add the support for extcon property according to type of connector
- extcon: Add the extcon_type to group each connector into five category

Thanks,
Chanwoo Choi