| From fbcd13df1e78eb2ba83a3c160eefe2d6f574beaf Mon Sep 17 00:00:00 2001 |
| From: Badhri Jagan Sridharan <badhri@google.com> |
| Date: Mon, 29 Nov 2021 16:18:25 -0800 |
| Subject: usb: typec: tcpm: Wait in SNK_DEBOUNCED until disconnect |
| |
| From: Badhri Jagan Sridharan <badhri@google.com> |
| |
| commit fbcd13df1e78eb2ba83a3c160eefe2d6f574beaf upstream. |
| |
| Stub from the spec: |
| "4.5.2.2.4.2 Exiting from AttachWait.SNK State |
| A Sink shall transition to Unattached.SNK when the state of both |
| the CC1 and CC2 pins is SNK.Open for at least tPDDebounce. |
| A DRP shall transition to Unattached.SRC when the state of both |
| the CC1 and CC2 pins is SNK.Open for at least tPDDebounce." |
| |
| This change makes TCPM to wait in SNK_DEBOUNCED state until |
| CC1 and CC2 pins is SNK.Open for at least tPDDebounce. Previously, |
| TCPM resets the port if vbus is not present in PD_T_PS_SOURCE_ON. |
| This causes TCPM to loop continuously when connected to a |
| faulty power source that does not present vbus. Waiting in |
| SNK_DEBOUNCED also ensures that TCPM is adherant to |
| "4.5.2.2.4.2 Exiting from AttachWait.SNK State" requirements. |
| |
| [ 6169.280751] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] |
| [ 6169.280759] state change TOGGLING -> SNK_ATTACH_WAIT [rev2 NONE_AMS] |
| [ 6169.280771] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev2 NONE_AMS] |
| [ 6169.282427] CC1: 0 -> 0, CC2: 5 -> 5 [state SNK_ATTACH_WAIT, polarity 0, connected] |
| [ 6169.450825] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] |
| [ 6169.450834] pending state change SNK_DEBOUNCED -> PORT_RESET @ 480 ms [rev2 NONE_AMS] |
| [ 6169.930892] state change SNK_DEBOUNCED -> PORT_RESET [delayed 480 ms] |
| [ 6169.931296] disable vbus discharge ret:0 |
| [ 6169.931301] Setting usb_comm capable false |
| [ 6169.932783] Setting voltage/current limit 0 mV 0 mA |
| [ 6169.932802] polarity 0 |
| [ 6169.933706] Requesting mux state 0, usb-role 0, orientation 0 |
| [ 6169.936689] cc:=0 |
| [ 6169.936812] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev2 NONE_AMS] |
| [ 6169.937157] CC1: 0 -> 0, CC2: 5 -> 0 [state PORT_RESET, polarity 0, disconnected] |
| [ 6170.036880] state change PORT_RESET -> PORT_RESET_WAIT_OFF [delayed 100 ms] |
| [ 6170.036890] state change PORT_RESET_WAIT_OFF -> SNK_UNATTACHED [rev2 NONE_AMS] |
| [ 6170.036896] Start toggling |
| [ 6170.041412] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected] |
| [ 6170.042973] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] |
| [ 6170.042976] state change TOGGLING -> SNK_ATTACH_WAIT [rev2 NONE_AMS] |
| [ 6170.042981] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev2 NONE_AMS] |
| [ 6170.213014] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] |
| [ 6170.213019] pending state change SNK_DEBOUNCED -> PORT_RESET @ 480 ms [rev2 NONE_AMS] |
| [ 6170.693068] state change SNK_DEBOUNCED -> PORT_RESET [delayed 480 ms] |
| [ 6170.693304] disable vbus discharge ret:0 |
| [ 6170.693308] Setting usb_comm capable false |
| [ 6170.695193] Setting voltage/current limit 0 mV 0 mA |
| [ 6170.695210] polarity 0 |
| [ 6170.695990] Requesting mux state 0, usb-role 0, orientation 0 |
| [ 6170.701896] cc:=0 |
| [ 6170.702181] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev2 NONE_AMS] |
| [ 6170.703343] CC1: 0 -> 0, CC2: 5 -> 0 [state PORT_RESET, polarity 0, disconnected] |
| |
| Fixes: f0690a25a140b8 ("staging: typec: USB Type-C Port Manager (tcpm)") |
| Cc: stable@vger.kernel.org |
| Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> |
| Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> |
| Link: https://lore.kernel.org/r/20211130001825.3142830-1-badhri@google.com |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/usb/typec/tcpm/tcpm.c | 4 ---- |
| 1 file changed, 4 deletions(-) |
| |
| --- a/drivers/usb/typec/tcpm/tcpm.c |
| +++ b/drivers/usb/typec/tcpm/tcpm.c |
| @@ -3293,11 +3293,7 @@ static void run_state_machine(struct tcp |
| tcpm_try_src(port) ? SRC_TRY |
| : SNK_ATTACHED, |
| 0); |
| - else |
| - /* Wait for VBUS, but not forever */ |
| - tcpm_set_state(port, PORT_RESET, PD_T_PS_SOURCE_ON); |
| break; |
| - |
| case SRC_TRY: |
| port->try_src_count++; |
| tcpm_set_cc(port, tcpm_rp_cc(port)); |