usb: onboard-hub: Set the reset gpio pin before freeing

In the usb_onboard_hub_remove, the reset gpio, if available, is
freed. The pin state however, remains unchanged, as set in the
usb_onboard_hub_reset. The hub is then left enabled.

During second onboard hub probing, the hub is initially enabled
(reset pin in state "0"), and then it is being reset by the reset
function (transition to "1" and then to "0"). Because of this,
the hub first disconnects from root hub, and then it connects again.

When the devices are being discovered in the usb_scan_port in the
usb_hub driver, initially there is the USB_PORT_STAT_CONNECTION bit
not set in portstatus, but USB_PORT_STAT_C_CONNECTION set in
portchange data (which is because disconnect event occurred first).
In this condition, the driver does not wait for devices to appear.
This can cause the hub (and all child devices) to be not enumerated
when rescanning on "usb reset" command.

To fix this, set the reset gpio to active in usb_onboard_hub_remove,
to put the hub into reset state.
However, in case the hub reset pin is by default held in high
state by HW before U-Boot takes over, in which case the USB hub is
active, then during the first probe it gets reset and we might get
into the same issue of the hub being not enumerated.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Lukasz Czechowski <lukasz.czechowski@thaumatec.com>

0 files changed, 0 insertions, 0 deletions