[PATCH 1/2] usb: dwc3: support continuous runtime PM with dual role

From: Martin Kepplinger
Date: Wed Mar 18 2020 - 04:35:27 EST


The DRD module calls dwc3_set_mode() on role switches, i.e. when a device is
being pugged in. In order to support continuous runtime power management when
plugging in / unplugging a cable, we need to call pm_runtime_get() in this path.

Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxx>
---
drivers/usb/dwc3/core.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index edc17155cb2b..7743c4de82e9 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -196,11 +196,16 @@ void dwc3_set_mode(struct dwc3 *dwc, u32 mode)
{
unsigned long flags;

+ pm_runtime_get(dwc->dev);
+
spin_lock_irqsave(&dwc->lock, flags);
dwc->desired_dr_role = mode;
spin_unlock_irqrestore(&dwc->lock, flags);

queue_work(system_freezable_wq, &dwc->drd_work);
+
+ pm_runtime_mark_last_busy(dwc->dev);
+ pm_runtime_put_autosuspend(dwc->dev);
}

u32 dwc3_core_fifo_space(struct dwc3_ep *dep, u8 type)
--
2.20.1