Re: [PATCH 12/12] extcon: axp288: Set USB role where necessary

From: Heikki Krogerus
Date: Fri Feb 16 2018 - 08:45:55 EST


On Fri, Feb 16, 2018 at 11:47:51AM +0100, Hans de Goede wrote:
> The AXP288 BC1.2 charger detection / extcon code may seem like a strange
> place to add code to control the USB role-switch on devices with an AXP288,
> but there are 2 reasons to do this inside the axp288 extcon code:
>
> 1) On many devices the USB role is controlled by ACPI AML code, but the AML
> code only switches between the host and none roles, because of Windows
> not really using device mode. To make device mode work we need to toggle
> between the none/device roles based on VBus presence, and the axp288
> extcon gets interrupts on VBus insertion / removal.
>
> 2) In order for our BC1.2 charger detection to work properly the role
> mux must be properly set to device mode before we do the detection.
>
> Also note the Kconfig help-text / obsolete depends on USB_PHY which are
> remnants from older never upstreamed code also controlling the mux from
> the axp288 extcon code.
>
> This commit also adds code to get notifications from the INT3496 extcon
> device, which is used on some devices to notify the kernel about id-pin
> changes instead of them being handled through AML code.
>
> This fixes:
> -Device mode not working on most CHT devices with an AXP288
> -Host mode not working on devices with an INT3496 ACPI device
> -Charger-type misdetection (always SDP) on devices with an INT3496 when the
> USB role (always) gets initialized as host
>
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>

After addressing Andy's comments:

Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>


Thanks,

--
heikki