On Fri, Mar 01, 2024 at 09:39:14AM +0530, Krishna Kurapati wrote:
When orientation switch is enabled in ucsi glink, there is a xhci probe failure seen when booting up in host mode in reverse orientation.
During bootup the following things happen in multiple drivers:
a) DWC3 controller driver initializes the core in device mode when the dr_mode is set to DRD. It relies on role_switch call to change role to host.
b) QMP driver initializes the lanes to TYPEC_ORIENTATION_NORMAL as a normal routine. It relies on the typec_switch_set call to get notified of orientation changes.
c) UCSI core reads the UCSI_GET_CONNECTOR_STATUS via the glink and provides initial role switch to dwc3 controller.
When booting up in host mode with orientation TYPEC_ORIENTATION_REVERSE, then we see the following things happening in order:
a) UCSI gives initial role as host to dwc3 controller ucsi_register_port. Upon receiving this notification, the dwc3 core needs to program GCTL from PRTCAP_DEVICE to PRTCAP_HOST and as part of this change, it asserts GCTL Core soft reset and waits for it to be completed before shifting it to host. Only after the reset is done will the dwc3_host_init be invoked and xhci is probed. DWC3 controller expects that the usb phy's are stable during this process i.e., the phy init is already done.
b) During the 100ms wait for GCTL core soft reset, the actual notification from PPM is received by ucsi_glink via pmic glink for changing role to host. The pmic_glink_ucsi_notify routine first sends the orientation change to QMP and then sends role to dwc3 via ucsi framework. This is happening exactly at the time GCTL core soft reset is being processed.
c) When QMP driver receives typec switch to TYPEC_ORIENTATION_REVERSE, it then re-programs the phy at the instant GCTL core soft reset has been asserted by dwc3 controller due to which the QMP PLL lock fails in qmp_combo_usb_power_on.
d) After the 100ms of GCTL core soft reset is completed, the dwc3 core goes for initializing the host mode and invokes xhci probe. But at this point the QMP is non-responsive and as a result, the xhci plat probe fails during xhci_reset.
Fix this by passing orientation switch to available ucsi instances if their gpio configuration is available before ucsi_register is invoked so that by the time, the pmic_glink_ucsi_notify provides typec_switch to QMP, the lane is already configured and the call would be a NOP thus not racing with role switch.
Cc: stable@vger.kernel.org Fixes: c6165ed2f425 ("usb: ucsi: glink: use the connector orientation GPIO to provide switch events") Suggested-by: Wesley Cheng quic_wcheng@quicinc.com Signed-off-by: Krishna Kurapati quic_kriskura@quicinc.com
Acked-by: Heikki Krogerus heikki.krogerus@linux.intel.com
drivers/usb/typec/ucsi/ucsi_glink.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/drivers/usb/typec/ucsi/ucsi_glink.c b/drivers/usb/typec/ucsi/ucsi_glink.c index 0bd3f6dee678..466df7b9f953 100644 --- a/drivers/usb/typec/ucsi/ucsi_glink.c +++ b/drivers/usb/typec/ucsi/ucsi_glink.c @@ -255,6 +255,20 @@ static void pmic_glink_ucsi_notify(struct work_struct *work) static void pmic_glink_ucsi_register(struct work_struct *work) { struct pmic_glink_ucsi *ucsi = container_of(work, struct pmic_glink_ucsi, register_work);
- int orientation;
- int i;
- for (i = 0; i < PMIC_GLINK_MAX_PORTS; i++) {
if (!ucsi->port_orientation[i])continue;orientation = gpiod_get_value(ucsi->port_orientation[i]);if (orientation >= 0) {typec_switch_set(ucsi->port_switch[i],orientation ? TYPEC_ORIENTATION_REVERSE: TYPEC_ORIENTATION_NORMAL);}- }
ucsi_register(ucsi->ucsi); } -- 2.34.1