usb: typec: tcpci: Check ROLE_CONTROL while interpreting CC_STATUS
While interpreting CC_STATUS, ROLE_CONTROL has to be read to make sure that CC1/CC2 is not forced presenting Rp/Rd. >From the TCPCI spec: 4.4.5.2 ROLE_CONTROL (Normative): The TCPM shall write B6 (DRP) = 0b and B3..0 (CC1/CC2) if it wishes to control the Rp/Rd directly instead of having the TCPC perform DRP toggling autonomously. When controlling Rp/Rd directly, the TCPM writes to B3..0 (CC1/CC2) each time it wishes to change the CC1/CC2 values. This control is used for TCPM-TCPC implementing Source or Sink only as well as when a connection has been detected via DRP toggling but the TCPM wishes to attempt Try.Src or Try.Snk. Table 4-22. CC_STATUS Register Definition: If (ROLE_CONTROL.CC1 = Rd) or ConnectResult=1) 00b: SNK.Open (Below maximum vRa) 01b: SNK.Default (Above minimum vRd-Connect) 10b: SNK.Power1.5 (Above minimum vRd-Connect) Detects Rp-1.5A 11b: SNK.Power3.0 (Above minimum vRd-Connect) Detects Rp-3.0A If (ROLE_CONTROL.CC2=Rd) or (ConnectResult=1) 00b: SNK.Open (Below maximum vRa) 01b: SNK.Default (Above minimum vRd-Connect) 10b: SNK.Power1.5 (Above minimum vRd-Connect) Detects Rp 1.5A 11b: SNK.Power3.0 (Above minimum vRd-Connect) Detects Rp 3.0A Fixes: 74e656d6 ("staging: typec: Type-C Port Controller Interface driver (tcpci)") Acked-by:Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by:
Badhri Jagan Sridharan <badhri@google.com> Link: https://lore.kernel.org/r/20210304070931.1947316-1-badhri@google.com Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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