USB: msm_otg: Always update state machine inputs during bus suspend/resume
UDC and HCD call usb_phy_set_suspend() to enter/exit LPM during bus
suspend/resume. The current code simply return if the hardware is
already in the requested state. OTG driver resume the hardware upon
receiving remote wakeup from the attached peripheral. The OTG state
and state machine inputs are not updated later when HCD requests resume.
This OTG state is stuck in A_SUSPEND after bus resume and next suspend
requests are ignored.
CRs-fixed: 425108
Change-Id: Icc276337166a09c81188f71279a1276013bebc4f
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
diff --git a/drivers/usb/otg/msm_otg.c b/drivers/usb/otg/msm_otg.c
index c69bc04..067f579 100644
--- a/drivers/usb/otg/msm_otg.c
+++ b/drivers/usb/otg/msm_otg.c
@@ -689,9 +689,12 @@
if (aca_enabled())
return 0;
- if (atomic_read(&motg->in_lpm) == suspend)
- return 0;
-
+ /*
+ * UDC and HCD call usb_phy_set_suspend() to enter/exit LPM
+ * during bus suspend/resume. Update the relevant state
+ * machine inputs and trigger LPM entry/exit. Checking
+ * in_lpm flag would avoid unnecessary work scheduling.
+ */
if (suspend) {
switch (phy->state) {
case OTG_STATE_A_WAIT_BCON:
@@ -701,14 +704,16 @@
case OTG_STATE_A_HOST:
pr_debug("host bus suspend\n");
clear_bit(A_BUS_REQ, &motg->inputs);
- queue_work(system_nrt_wq, &motg->sm_work);
+ if (!atomic_read(&motg->in_lpm))
+ queue_work(system_nrt_wq, &motg->sm_work);
break;
case OTG_STATE_B_PERIPHERAL:
pr_debug("peripheral bus suspend\n");
if (!(motg->caps & ALLOW_LPM_ON_DEV_SUSPEND))
break;
set_bit(A_BUS_SUSPEND, &motg->inputs);
- queue_work(system_nrt_wq, &motg->sm_work);
+ if (!atomic_read(&motg->in_lpm))
+ queue_work(system_nrt_wq, &motg->sm_work);
break;
default:
@@ -716,20 +721,29 @@
}
} else {
switch (phy->state) {
+ case OTG_STATE_A_WAIT_BCON:
+ /* Remote wakeup or resume */
+ set_bit(A_BUS_REQ, &motg->inputs);
+ /* ensure hardware is not in low power mode */
+ if (atomic_read(&motg->in_lpm))
+ pm_runtime_resume(phy->dev);
+ break;
case OTG_STATE_A_SUSPEND:
/* Remote wakeup or resume */
set_bit(A_BUS_REQ, &motg->inputs);
phy->state = OTG_STATE_A_HOST;
/* ensure hardware is not in low power mode */
- pm_runtime_resume(phy->dev);
+ if (atomic_read(&motg->in_lpm))
+ pm_runtime_resume(phy->dev);
break;
case OTG_STATE_B_PERIPHERAL:
pr_debug("peripheral bus resume\n");
if (!(motg->caps & ALLOW_LPM_ON_DEV_SUSPEND))
break;
clear_bit(A_BUS_SUSPEND, &motg->inputs);
- queue_work(system_nrt_wq, &motg->sm_work);
+ if (atomic_read(&motg->in_lpm))
+ queue_work(system_nrt_wq, &motg->sm_work);
break;
default:
break;