usb: typec: fusb302: Check vconn is off when we start toggling

usb: typec: fusb302: Check vconn is off when we start toggling

BugLink: https://bugs.launchpad.net/bugs/1838824
[ Upstream commit 32a155b1a83d6659e2272e8e1eec199667b1897e ]

The datasheet says the vconn MUST be off when we start toggling. The
tcpm.c state-machine is responsible to make sure vconn is off, but lets
add a WARN to catch any cases where vconn is not off for some reason.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>