diff options
author | Badhri Jagan Sridharan <badhri@google.com> | 2022-01-21 17:55:19 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-01-25 18:41:18 +0100 |
commit | 90b8aa9f5b09edae6928c0561f933fec9f7a9987 (patch) | |
tree | 9959b1135dce06ef1ec75dac62bb91a19506455c /drivers/usb | |
parent | 147ab5376f18045da9f22a8262185707745bbf77 (diff) | |
download | linux-90b8aa9f5b09edae6928c0561f933fec9f7a9987.tar.gz |
usb: typec: tcpm: Do not disconnect while receiving VBUS off
With some chargers, vbus might momentarily raise above VSAFE5V and fall
back to 0V before tcpm gets to read port->tcpc->get_vbus. This will
will report a VBUS off event causing TCPM to transition to
SNK_UNATTACHED where it should be waiting in either SNK_ATTACH_WAIT
or SNK_DEBOUNCED state. This patch makes TCPM avoid vbus off events
while in SNK_ATTACH_WAIT or SNK_DEBOUNCED state.
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."
[23.194131] CC1: 0 -> 0, CC2: 0 -> 5 [state SNK_UNATTACHED, polarity 0, connected]
[23.201777] state change SNK_UNATTACHED -> SNK_ATTACH_WAIT [rev3 NONE_AMS]
[23.209949] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS]
[23.300579] VBUS off
[23.300668] state change SNK_ATTACH_WAIT -> SNK_UNATTACHED [rev3 NONE_AMS]
[23.301014] VBUS VSAFE0V
[23.301111] Start toggling
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/20220122015520.332507-1-badhri@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
-rw-r--r-- | drivers/usb/typec/tcpm/tcpm.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index 59d4fa2443f2..b8afe3d8c882 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -5156,7 +5156,8 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port) case SNK_TRYWAIT_DEBOUNCE: break; case SNK_ATTACH_WAIT: - tcpm_set_state(port, SNK_UNATTACHED, 0); + case SNK_DEBOUNCED: + /* Do nothing, as TCPM is still waiting for vbus to reaach VSAFE5V to connect */ break; case SNK_NEGOTIATE_CAPABILITIES: |