Re: [PATCH v3] usb: dwc3: Add support for VBUS power control

From: Mark Brown
Date: Mon Jul 27 2020 - 06:23:36 EST


On Sun, Jul 26, 2020 at 09:10:39AM +0200, Mike Looijmans wrote:
> On 23-07-2020 13:05, Mark Brown wrote:

> > Does the device actually support running without power so that's a thing
> > that can happen? _get_optional() should only ever be used for supplies
> > that may be physically absent.

> It's the 5V VBUS power for the USB "plug" that's being controlled here. It
> must turned on when the controller is in "host" mode. Some boards arrange
> this in hardware through the PHY, and some just don't have any control at
> all and have it permanently on or off. On a board where the 5V is controlled
> using a GPIO line or an I2C chip, this patch is required to make it work.

That sounds like the driver should not be using _get_optional() then.

Attachment: signature.asc
Description: PGP signature