usb: dwc2: host: Protect PCGCTL with lock in dwc2_port_resume()
From code inspection, it appears to be unsafe to do a read-modify-write
of PCGCTL in dwc2_port_resume(). Let's make sure the spinlock is held
around this operation.
Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index af4e4a2..e79baf7 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -1500,6 +1500,8 @@
u32 hprt0;
u32 pcgctl;
+ spin_lock_irqsave(&hsotg->lock, flags);
+
/*
* If hibernation is supported, Phy clock is already resumed
* after registers restore.
@@ -1508,10 +1510,11 @@
pcgctl = dwc2_readl(hsotg->regs + PCGCTL);
pcgctl &= ~PCGCTL_STOPPCLK;
dwc2_writel(pcgctl, hsotg->regs + PCGCTL);
+ spin_unlock_irqrestore(&hsotg->lock, flags);
usleep_range(20000, 40000);
+ spin_lock_irqsave(&hsotg->lock, flags);
}
- spin_lock_irqsave(&hsotg->lock, flags);
hprt0 = dwc2_read_hprt0(hsotg);
hprt0 |= HPRT0_RES;
hprt0 &= ~HPRT0_SUSP;