[PATCH] usb: dwc3: gadget: Restart DWC3 gadget when enabling pullup

From: Wesley Cheng
Date: Thu Nov 19 2020 - 19:15:51 EST


usb_gadget_deactivate/usb_gadget_activate does not execute the UDC start
operation, which may leave EP0 disabled and event IRQs disabled when
re-activating the function. Move the enabling/disabling of USB EP0 and
device event IRQs to be performed in the pullup routine.

Fixes: ae7e86108b12 ("usb: dwc3: Stop active transfers before halting the
controller")

Reported-by: Michael Tretter <m.tretter@xxxxxxxxxxxxxx>
Signed-off-by: Wesley Cheng <wcheng@xxxxxxxxxxxxxx>
---
drivers/usb/dwc3/gadget.c | 14 +++-----------
1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 5d879b7606d5..922c8b76e534 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1988,6 +1988,7 @@ static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)

static void dwc3_gadget_disable_irq(struct dwc3 *dwc);
static void __dwc3_gadget_stop(struct dwc3 *dwc);
+static int __dwc3_gadget_start(struct dwc3 *dwc);

static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
{
@@ -2050,6 +2051,8 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
dwc->ev_buf->lpos = (dwc->ev_buf->lpos + count) %
dwc->ev_buf->length;
}
+ } else {
+ __dwc3_gadget_start(dwc);
}

ret = dwc3_gadget_run_stop(dwc, is_on, false);
@@ -2224,10 +2227,6 @@ static int dwc3_gadget_start(struct usb_gadget *g,
}

dwc->gadget_driver = driver;
-
- if (pm_runtime_active(dwc->dev))
- __dwc3_gadget_start(dwc);
-
spin_unlock_irqrestore(&dwc->lock, flags);

return 0;
@@ -2253,13 +2252,6 @@ static int dwc3_gadget_stop(struct usb_gadget *g)
unsigned long flags;

spin_lock_irqsave(&dwc->lock, flags);
-
- if (pm_runtime_suspended(dwc->dev))
- goto out;
-
- __dwc3_gadget_stop(dwc);
-
-out:
dwc->gadget_driver = NULL;
spin_unlock_irqrestore(&dwc->lock, flags);

--
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