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: I0dadca78c8ead9ccd48f25d958015885b28917c1
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 c6fe765..269542a 100644
--- a/drivers/usb/otg/msm_otg.c
+++ b/drivers/usb/otg/msm_otg.c
@@ -771,10 +771,12 @@
if (aca_enabled())
return 0;
- if (atomic_read(&motg->in_lpm) == suspend &&
- !atomic_read(&motg->suspend_work_pending))
- 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:
@@ -784,16 +786,18 @@
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);
- atomic_set(&motg->suspend_work_pending, 1);
- queue_delayed_work(system_nrt_wq, &motg->suspend_work,
- USB_SUSPEND_DELAY_TIME);
+ if (!atomic_read(&motg->in_lpm))
+ queue_delayed_work(system_nrt_wq,
+ &motg->suspend_work,
+ USB_SUSPEND_DELAY_TIME);
break;
default:
@@ -801,20 +805,29 @@
}
} 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;
@@ -2945,8 +2958,10 @@
{
struct msm_otg *motg =
container_of(w, struct msm_otg, suspend_work.work);
- atomic_set(&motg->suspend_work_pending, 0);
- msm_otg_sm_work(&motg->sm_work);
+
+ /* This work is only for device bus suspend */
+ if (test_bit(A_BUS_SUSPEND, &motg->inputs))
+ msm_otg_sm_work(&motg->sm_work);
}
static irqreturn_t msm_otg_irq(int irq, void *data)
diff --git a/include/linux/usb/msm_hsusb.h b/include/linux/usb/msm_hsusb.h
index d6fbc64..5b7820d 100644
--- a/include/linux/usb/msm_hsusb.h
+++ b/include/linux/usb/msm_hsusb.h
@@ -333,7 +333,6 @@
bool sm_work_pending;
atomic_t pm_suspended;
atomic_t in_lpm;
- atomic_t suspend_work_pending;
int async_int;
unsigned cur_power;
struct delayed_work chg_work;