usb: typec: tcpm: reset hard_reset_count for any disconnect
Current tcpm_detach() only reset hard_reset_count if port->attached is true, this may cause this counter clear is missed if the CC disconnect event is generated after tcpm_port_reset() is done by other events, e.g. VBUS off comes first before CC disconect for a power sink, in that case the first tcpm_detach() will only clear port->attached flag but leave hard_reset_count there because tcpm_port_is_disconnected() is still false, then later tcpm_detach() by CC disconnect will directly return due to port->attached is cleared, finally this will result tcpm will not try hard reset or error recovery for later attach. ChiYuan reported this issue on his platform with below tcpm trace: After power sink session setup after hard reset 2 times, detach from the power source and then attach: [ 4848.046358] VBUS off [ 4848.046384] state change SNK_READY -> SNK_UNATTACHED [ 4848.050908] Setting voltage/current limit 0 mV 0 mA [ 4848.050936] polarity 0 [ 4848.052593] Requesting mux state 0, usb-role 0, orientation 0 [ 4848.053222] Start toggling [ 4848.086500] state change SNK_UNATTACHED -> TOGGLING [ 4848.089983] CC1: 0 -> 0, CC2: 3 -> 3 [state TOGGLING, polarity 0, connected] [ 4848.089993] state change TOGGLING -> SNK_ATTACH_WAIT [ 4848.090031] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @200 ms [ 4848.141162] CC1: 0 -> 0, CC2: 3 -> 0 [state SNK_ATTACH_WAIT, polarity 0, disconnected] [ 4848.141170] state change SNK_ATTACH_WAIT -> SNK_ATTACH_WAIT [ 4848.141184] pending state change SNK_ATTACH_WAIT -> SNK_UNATTACHED @20 ms [ 4848.163156] state change SNK_ATTACH_WAIT -> SNK_UNATTACHED [delayed 20 ms] [ 4848.163162] Start toggling [ 4848.216918] CC1: 0 -> 0, CC2: 0 -> 3 [state TOGGLING, polarity 0, connected] [ 4848.216954] state change TOGGLING -> SNK_ATTACH_WAIT [ 4848.217080] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @200 ms [ 4848.231771] CC1: 0 -> 0, CC2: 3 -> 0 [state SNK_ATTACH_WAIT, polarity 0, disconnected] [ 4848.231800] state change SNK_ATTACH_WAIT -> SNK_ATTACH_WAIT [ 4848.231857] pending state change SNK_ATTACH_WAIT -> SNK_UNATTACHED @20 ms [ 4848.256022] state change SNK_ATTACH_WAIT -> SNK_UNATTACHED [delayed20 ms] [ 4848.256049] Start toggling [ 4848.871148] VBUS on [ 4848.885324] CC1: 0 -> 0, CC2: 0 -> 3 [state TOGGLING, polarity 0, connected] [ 4848.885372] state change TOGGLING -> SNK_ATTACH_WAIT [ 4848.885548] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @200 ms [ 4849.088240] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed200 ms] [ 4849.088284] state change SNK_DEBOUNCED -> SNK_ATTACHED [ 4849.088291] polarity 1 [ 4849.088769] Requesting mux state 1, usb-role 2, orientation 2 [ 4849.088895] state change SNK_ATTACHED -> SNK_STARTUP [ 4849.088907] state change SNK_STARTUP -> SNK_DISCOVERY [ 4849.088915] Setting voltage/current limit 5000 mV 0 mA [ 4849.088927] vbus=0 charge:=1 [ 4849.090505] state change SNK_DISCOVERY -> SNK_WAIT_CAPABILITIES [ 4849.090828] pending state change SNK_WAIT_CAPABILITIES -> SNK_READY @240 ms [ 4849.335878] state change SNK_WAIT_CAPABILITIES -> SNK_READY [delayed240 ms] this patch fix this issue by clear hard_reset_count at any cases of cc disconnect, í.e. don't check port->attached flag. Fixes: 4b4e02c8 ("typec: tcpm: Move out of staging") Cc: stable@vger.kernel.org Reported-and-tested-by: ChiYuan Huang <cy_huang@richtek.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Li Jun <jun.li@nxp.com> Link: https://lore.kernel.org/r/1602500592-3817-1-git-send-email-jun.li@nxp.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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