[PATCH 5.4 152/168] usb: typec: tcpm: Ignore CC and vbus changes in PORT_RESET change

From: Greg Kroah-Hartman
Date: Tue Apr 28 2020 - 14:44:10 EST


From: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>

commit 901789745a053286e0ced37960d44fa60267b940 upstream.

After PORT_RESET, the port is set to the appropriate
default_state. Ignore processing CC changes here as this
could cause the port to be switched into sink states
by default.

echo source > /sys/class/typec/port0/port_type

Before:
[ 154.528547] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms
[ 154.528560] CC1: 0 -> 0, CC2: 3 -> 0 [state PORT_RESET, polarity 0, disconnected]
[ 154.528564] state change PORT_RESET -> SNK_UNATTACHED

After:
[ 151.068814] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev3 NONE_AMS]
[ 151.072440] CC1: 3 -> 0, CC2: 0 -> 0 [state PORT_RESET, polarity 0, disconnected]
[ 151.172117] state change PORT_RESET -> PORT_RESET_WAIT_OFF [delayed 100 ms]
[ 151.172136] pending state change PORT_RESET_WAIT_OFF -> SRC_UNATTACHED @ 870 ms [rev3 NONE_AMS]
[ 152.060106] state change PORT_RESET_WAIT_OFF -> SRC_UNATTACHED [delayed 870 ms]
[ 152.060118] Start toggling

Signed-off-by: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200402215947.176577-1-badhri@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/typec/tcpm/tcpm.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -3768,6 +3768,14 @@ static void _tcpm_cc_change(struct tcpm_
*/
break;

+ case PORT_RESET:
+ case PORT_RESET_WAIT_OFF:
+ /*
+ * State set back to default mode once the timer completes.
+ * Ignore CC changes here.
+ */
+ break;
+
default:
if (tcpm_port_is_disconnected(port))
tcpm_set_state(port, unattached_state(port), 0);
@@ -3829,6 +3837,15 @@ static void _tcpm_pd_vbus_on(struct tcpm
case SRC_TRY_DEBOUNCE:
/* Do nothing, waiting for sink detection */
break;
+
+ case PORT_RESET:
+ case PORT_RESET_WAIT_OFF:
+ /*
+ * State set back to default mode once the timer completes.
+ * Ignore vbus changes here.
+ */
+ break;
+
default:
break;
}
@@ -3882,10 +3899,19 @@ static void _tcpm_pd_vbus_off(struct tcp
case PORT_RESET_WAIT_OFF:
tcpm_set_state(port, tcpm_default_state(port), 0);
break;
+
case SRC_TRY_WAIT:
case SRC_TRY_DEBOUNCE:
/* Do nothing, waiting for sink detection */
break;
+
+ case PORT_RESET:
+ /*
+ * State set back to default mode once the timer completes.
+ * Ignore vbus changes here.
+ */
+ break;
+
default:
if (port->pwr_role == TYPEC_SINK &&
port->attached)