Quoting Jack Pham (2019-09-05 10:58:02)

Hi Jorge, Bjorn,

On Thu, Sep 05, 2019 at 09:18:57AM +0200, Jorge Ramirez wrote:

quoted

On 9/4/19 01:34, Bjorn Andersson wrote:

quoted

On Tue 03 Sep 14:45 PDT 2019, Stephen Boyd wrote:

quoted

that would need an of_regulator_get() sort of API that can get the
regulator out of there? Or to make the connector into a struct device
that can get the regulator out per some generic connector driver and
then pass it through to the USB controller when it asks for it. Maybe
try to prototype that out?

The examples given in the DT bindings describes the connector as a child
of a PMIC, with of_graph somehow tying it to the various inputs. But in
these examples vbus is handled by implicitly inside the MFD, where
extcon is informed about the plug event they toggle vbus as well.

In our case we have a extcon-usb-gpio to detect mode, which per Jorge's
proposal will trickle down to the PHY and become a regulator calls on
either some external regulator or more typically one of the chargers in
the system.

Interesting you mention extcon-usb-gpio. I thought extcon at least from
bindings perspective is passé now. Maybe this is what you need (just
landed in usb-next):

usb: common: add USB GPIO based connection detection driver
https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git/commit/?h=usb-next&id=4602f3bff2669012c1147eecfe74c121765f5c56

dt-bindings: usb: add binding for USB GPIO based connection detection driver
https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git/commit/?h=usb-next&id=f651c73e71f53f65e9846677d79d8e120452b59f

Fortunately this new driver might check the right boxes for you:
- usb connector binding
- ID detect GPIO
- vbus-supply regulator

With that, I think you can also keep the connector subnode out of the
SSPHY node well, and similarly get rid of the vbus toggle handling from
the PHY driver.

The big thing missing now is that this driver replaces extcon
completely, so we'll need handling in dwc3/dwc3-qcom to retrieve the
role switch state to know when host mode is entered. I saw this a while
back but don't think it got picked up:

https://patchwork.kernel.org/patch/10909981/

Yes this looks like the approach that should be taken. One question
though, is this a micro-b connector or a type-c connector on the board?
I thought it was a type-c, so then this USB gpio based connection driver
isn't an exact fit?


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