Commit 8f2960e1 authored by Aran Dalton's avatar Aran Dalton Committed by Matthias Männich
Browse files

UPSTREAM: usb:typec:tcpm:support double Rp to Vbus cable as sink



The USB Type-C Cable and Connector Specification defines the wire
connections for the USB Type-C to USB 2.0 Standard-A cable assembly
(Release 2.2, Chapter 3.5.2).
The Notes says that Pin A5 (CC) of the USB Type-C plug shall be connected
to Vbus through a resister Rp.
However, there is a large amount of such double Rp connected to Vbus
non-standard cables which produced by UGREEN circulating on the market, and
it can affects the normal operations of the state machine easily,
especially to CC1 and CC2 be pulled up at the same time.
In fact, we can regard those cables as sink to avoid abnormal state.

Message as follow:
[   58.900212] VBUS on
[   59.265433] CC1: 0 -> 3, CC2: 0 -> 3 [state TOGGLING, polarity 0, connected]
[   62.623308] CC1: 3 -> 0, CC2: 3 -> 0 [state TOGGLING, polarity 0, disconnected]
[   62.625006] VBUS off
[   62.625012] VBUS VSAFE0V

Signed-off-by: default avatarMichael Wu <michael@allwinnertech.com>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Reviewed-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230920063030.66312-1-michael@allwinnertech.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Bug: 311131373
(cherry picked from commit dbc1defe)
Signed-off-by: default avatarAran Dalton <arda@allwinnertech.com>
Change-Id: I1a7b897bfc9557b4518442d098aca7504bb49187
parent 643cef88
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