usb: cdns3: gadget: own the lock wrongly at the suspend routine
When the system goes to suspend, if the controller is at device mode with
cable connecting to host, the call stack is: cdns3_suspend->
cdns3_gadget_suspend -> cdns3_disconnect_gadget, after cdns3_disconnect_gadget
is called, it owns lock wrongly, it causes the system being deadlock after
resume due to at cdns3_device_thread_irq_handler, it tries to get the lock,
but can't get it forever.
To fix it, we delete the unlock-lock operations at cdns3_disconnect_gadget,
and do it at the caller.
Fixes: b1234e3b3b26 ("usb: cdns3: add runtime PM support")
Acked-by: Pawel Laszczak <pawell@cadence.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
index 36c8c1a..66c1e67 100644
--- a/drivers/usb/cdns3/gadget.c
+++ b/drivers/usb/cdns3/gadget.c
@@ -1750,11 +1750,8 @@
static void cdns3_disconnect_gadget(struct cdns3_device *priv_dev)
{
- if (priv_dev->gadget_driver && priv_dev->gadget_driver->disconnect) {
- spin_unlock(&priv_dev->lock);
+ if (priv_dev->gadget_driver && priv_dev->gadget_driver->disconnect)
priv_dev->gadget_driver->disconnect(&priv_dev->gadget);
- spin_lock(&priv_dev->lock);
- }
}
/**
@@ -1765,6 +1762,7 @@
*/
static void cdns3_check_usb_interrupt_proceed(struct cdns3_device *priv_dev,
u32 usb_ists)
+__must_hold(&priv_dev->lock)
{
int speed = 0;
@@ -1789,7 +1787,9 @@
/* Disconnection detected */
if (usb_ists & (USB_ISTS_DIS2I | USB_ISTS_DISI)) {
+ spin_unlock(&priv_dev->lock);
cdns3_disconnect_gadget(priv_dev);
+ spin_lock(&priv_dev->lock);
priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
usb_gadget_set_state(&priv_dev->gadget, USB_STATE_NOTATTACHED);
cdns3_hw_reset_eps_config(priv_dev);
@@ -3275,10 +3275,13 @@
}
static int cdns3_gadget_suspend(struct cdns3 *cdns, bool do_wakeup)
+__must_hold(&cdns->lock)
{
struct cdns3_device *priv_dev = cdns->gadget_dev;
+ spin_unlock(&cdns->lock);
cdns3_disconnect_gadget(priv_dev);
+ spin_lock(&cdns->lock);
priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
usb_gadget_set_state(&priv_dev->gadget, USB_STATE_NOTATTACHED);
