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: Michael Wu <michael@allwinnertech.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Link: https://lore.kernel.org/r/20230920063030.66312-1-michael@allwinnertech.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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