On Fri, Sep 06, 2024 at 08:58:53AM +0200, Christian A. Ehrhardt wrote: > If the busy indicator is set, all other fields in CCI should be > clear according to the spec. However, some UCSI implementations do > not follow this rule and report bogus data in CCI along with the > busy indicator. Ignore the contents of CCI if the busy indicator is > set. > > If a command timeout is hit it is possible that the EVENT_PENDING > bit is cleared while connector work is still scheduled which can > cause the EVENT_PENDING bit to go out of sync with scheduled connector > work. Check and set the EVENT_PENDING bit on entry to > ucsi_handle_connector_change() to fix this. > > Finally, check UCSI_CCI_BUSY before the return code of ->sync_control. > This ensures that the command is cancelled even if ->sync_control > returns an error (most likely -ETIMEDOUT). > > Reported-by: Anurag Bijea <icaliberdev@xxxxxxxxx> > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219108 > Bisected-by: Christian Heusel <christian@xxxxxxxxx> > Tested-by: Anurag Bijea <icaliberdev@xxxxxxxxx> > Fixes: de52aca4d9d5 ("usb: typec: ucsi: Never send a lone connector change ack") > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Christian A. Ehrhardt <lk@xxxxxxx> Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx> > --- > drivers/usb/typec/ucsi/ucsi.c | 18 ++++++++++++------ > 1 file changed, 12 insertions(+), 6 deletions(-) > > diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c > index 4039851551c1..d6d61606bbcf 100644 > --- a/drivers/usb/typec/ucsi/ucsi.c > +++ b/drivers/usb/typec/ucsi/ucsi.c > @@ -38,6 +38,10 @@ > > void ucsi_notify_common(struct ucsi *ucsi, u32 cci) > { > + /* Ignore bogus data in CCI if busy indicator is set. */ > + if (cci & UCSI_CCI_BUSY) > + return; > + > if (UCSI_CCI_CONNECTOR(cci)) > ucsi_connector_change(ucsi, UCSI_CCI_CONNECTOR(cci)); > > @@ -107,15 +111,13 @@ static int ucsi_run_command(struct ucsi *ucsi, u64 command, u32 *cci, > size = clamp(size, 0, 16); > > ret = ucsi->ops->sync_control(ucsi, command); > - if (ret) > - return ret; > - > - ret = ucsi->ops->read_cci(ucsi, cci); > - if (ret) > - return ret; > + if (ucsi->ops->read_cci(ucsi, cci)) > + return -EIO; > > if (*cci & UCSI_CCI_BUSY) > return -EBUSY; > + if (ret) > + return ret; > > if (!(*cci & UCSI_CCI_COMMAND_COMPLETE)) > return -EIO; > @@ -1249,6 +1251,10 @@ static void ucsi_handle_connector_change(struct work_struct *work) > > mutex_lock(&con->lock); > > + if (!test_and_set_bit(EVENT_PENDING, &ucsi->flags)) > + dev_err_once(ucsi->dev, "%s entered without EVENT_PENDING\n", > + __func__); > + > command = UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num); > > ret = ucsi_send_command_common(ucsi, command, &con->status, > -- > 2.43.0 -- heikki
