EHCI: HSIC: Fix race between HSIC runtime resume and remote wakeup
HSIC runtime resume initiated by an interface driver and remote wakeup
gpio interrupt handler can run in parallel. If HSIC runtime resume is
triggered by runtime PM core, pm_runtime_get call will fail in wakeup
interrupt handler. Check the return code and decrement the PM usage
counter.
CRs-Fixed: 403708
Change-Id: I3108c4aed86723a629a98bdbc461679178727fe5
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
diff --git a/drivers/usb/host/ehci-msm-hsic.c b/drivers/usb/host/ehci-msm-hsic.c
index b7f1878..765d4ad 100644
--- a/drivers/usb/host/ehci-msm-hsic.c
+++ b/drivers/usb/host/ehci-msm-hsic.c
@@ -1279,6 +1279,7 @@
static irqreturn_t msm_hsic_wakeup_irq(int irq, void *data)
{
struct msm_hsic_hcd *mehci = data;
+ int ret;
mehci->wakeup_int_cnt++;
dbg_log_event(NULL, "Remote Wakeup IRQ", mehci->wakeup_int_cnt);
@@ -1296,8 +1297,17 @@
spin_unlock(&mehci->wakeup_lock);
if (!atomic_read(&mehci->pm_usage_cnt)) {
- atomic_set(&mehci->pm_usage_cnt, 1);
- pm_runtime_get(mehci->dev);
+ ret = pm_runtime_get(mehci->dev);
+ /*
+ * HSIC runtime resume can race with us.
+ * if we are active (ret == 1) or resuming
+ * (ret == -EINPROGRESS), decrement the
+ * PM usage counter before returning.
+ */
+ if ((ret == 1) || (ret == -EINPROGRESS))
+ pm_runtime_put_noidle(mehci->dev);
+ else
+ atomic_set(&mehci->pm_usage_cnt, 1);
}
return IRQ_HANDLED;