staging: typec: tcpm: add cc change handling in src states

In the case that the lower layer driver reports a cc change directly
from SINK state to SOURCE state, TCPM doesn't handle these cc change
in SRC_SEND_CAPABILITIES, SRC_READY states. And with SRC_ATTACHED
state, the change is not handled as the port is still considered
connected.

[49606.131672] state change DRP_TOGGLING -> SRC_ATTACH_WAIT
[49606.131701] pending state change SRC_ATTACH_WAIT -> SRC_ATTACHED @
200 ms
[49606.329952] state change SRC_ATTACH_WAIT -> SRC_ATTACHED [delayed 200
ms]
[49606.329978] polarity 0
[49606.329989] Requesting mux mode 1, config 0, polarity 0
[49606.349416] vbus:=1 charge=0
[49606.372274] pending state change SRC_ATTACHED -> SRC_UNATTACHED @ 480
ms
[49606.372431] VBUS on
[49606.372488] state change SRC_ATTACHED -> SRC_STARTUP
...
(the lower layer driver reports a direct change from source to sink)
[49606.536927] pending state change SRC_SEND_CAPABILITIES ->
SRC_SEND_CAPABILITIES @ 150 ms
[49606.547244] CC1: 2 -> 5, CC2: 0 -> 0 [state SRC_SEND_CAPABILITIES,
polarity 0, connected]

This can happen when the lower layer driver and/or the hardware
handles a portion of the Type-C state machine work, and quietly goes
through the unattached state.

Originally-from: Yueyao Zhu <yueyao@google.com>
Signed-off-by: Badhri Jagan Sridharan <Badhri@google.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/typec/tcpm.c b/drivers/staging/typec/tcpm.c
index 9507f83..fa2e59b 100644 (file)
--- a/drivers/staging/typec/tcpm.c
+++ b/drivers/staging/typec/tcpm.c
@@ -2879,10 +2879,12 @@ static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1,
                        tcpm_set_state(port, SRC_ATTACH_WAIT, 0);
                break;
        case SRC_ATTACHED:
-               if (tcpm_port_is_disconnected(port))
+       case SRC_SEND_CAPABILITIES:
+       case SRC_READY:
+               if (tcpm_port_is_disconnected(port) ||
+                   !tcpm_port_is_source(port))
                        tcpm_set_state(port, SRC_UNATTACHED, 0);
                break;
-
        case SNK_UNATTACHED:
                if (tcpm_port_is_sink(port))
                        tcpm_set_state(port, SNK_ATTACH_WAIT, 0);