On 9/27/2023 1:24 AM, Alan Stern wrote:
On Wed, Sep 27, 2023 at 01:07:08AM +0530, Krishna Kurapati wrote:
In the event, gadget_connect call (which invokes pullup) fails,
s/event,/event/
propagate the error to udc bind operation which inturn sends the
s/inturn/in turn/
error to configfs. The userspace can then retry enumeartion if
s/enumeartion/enumeration/
it chooses to.
Signed-off-by: Krishna Kurapati <quic_kriskura@xxxxxxxxxxx>
---
Changes in v4: Fixed mutex locking imbalance during connect_control
failure
Link to v3: https://lore.kernel.org/all/20230510075252.31023-3-quic_kriskura@xxxxxxxxxxx/
drivers/usb/gadget/udc/core.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index 7d49d8a0b00c..53af25a333a1 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -1125,12 +1125,16 @@ EXPORT_SYMBOL_GPL(usb_gadget_set_state);
/* ------------------------------------------------------------------------- */
/* Acquire connect_lock before calling this function. */
-static void usb_udc_connect_control_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock)
+static int usb_udc_connect_control_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock)
{
+ int ret;
+
if (udc->vbus)
- usb_gadget_connect_locked(udc->gadget);
+ ret = usb_gadget_connect_locked(udc->gadget);
else
- usb_gadget_disconnect_locked(udc->gadget);
+ ret = usb_gadget_disconnect_locked(udc->gadget);
+
+ return ret;
You don't actually need the new variable ret. You can just do:
if (udc->vbus)
return usb_gadget_connect_locked(udc->gadget);
else
return usb_gadget_disconnect_locked(udc->gadget);
}
static void vbus_event_work(struct work_struct *work)
@@ -1604,12 +1608,23 @@ static int gadget_bind_driver(struct device *dev)
}
usb_gadget_enable_async_callbacks(udc);
udc->allow_connect = true;
- usb_udc_connect_control_locked(udc);
+ ret = usb_udc_connect_control_locked(udc);
+ if (ret) {
+ mutex_unlock(&udc->connect_lock);
+ goto err_connect_control;
+ }
+
mutex_unlock(&udc->connect_lock);
kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
return 0;
+ err_connect_control:
+ usb_gadget_disable_async_callbacks(udc);
+ if (gadget->irq)
+ synchronize_irq(gadget->irq);
+ usb_gadget_udc_stop_locked(udc);
Not good -- usb_gadget_udc_stop_locked() expects you to be holding
udc->connect_lock, but you just dropped the lock! Also, you never set
udc->allow_connect back to false.
You should move the mutex_unlock() call from inside the "if" statement
to down here, and add a line for udc->allow_connect.
Hi Alan,
Thanks for the review. Will push v5 addressing the changes.
Regards,
Krishna,
