On 9/27/2023 2:54 AM, Alan Stern wrote:
On Wed, Sep 27, 2023 at 01:54:34AM +0530, Krishna Kurapati PSSNV wrote:
On 9/27/2023 1:36 AM, Krishna Kurapati PSSNV wrote:
drivers/usb/gadget/udc/core.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)
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.
Hi Alan,
I tried out the following diff:
- usb_udc_connect_control_locked(udc);
+ ret = usb_udc_connect_control_locked(udc);
+ if (ret)
+ goto err_connect_control;
+
mutex_unlock(&udc->connect_lock);
kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
return 0;
+ err_connect_control:
+ udc->allow_connect = false;
+ usb_gadget_disable_async_callbacks(udc);
+ if (gadget->irq)
+ synchronize_irq(gadget->irq);
+ usb_gadget_udc_stop_locked(udc);
+ mutex_unlock(&udc->connect_lock);
+
If I clear UDC and fail dwc3 soft reset on purpose, I see UDC_store failing:
#echo a600000.usb > /sys/kernel/config/usb_gadget/g1/UDC
[ 127.394087] dwc3 a600000.usb: request 000000003f43f907 was not queued to
ep0out
[ 127.401637] udc a600000.usb: failed to start g1: -110
[ 127.406841] configfs-gadget.g1: probe of gadget.0 failed with error -110
[ 127.413809] UDC core: g1: couldn't find an available UDC or it's busy
The same output came when I tested v4 as well. Every time soft_reset would
fail when I try to write to UDC, UDC_store fails and above log will come up.
Isn't that what you want? I thought the whole purpose of this patch was
to make it so that configfs would realize when
usb_udc_connect_control_locked() had failed. So you should be happy
that the log shows a failure occurred.
>> Can you help confirm if the diff above is proper as I don't see any
diff in
the logs in v4 and about to push v5.
"Diff in the logs in v4"? What does that mean? A diff is a comparison
between two text files (often between before-and-after versions of a
source code file). Why would you expect a diff to show up in the logs?
This revised patch looks okay to me.
Thanks for the confirmation. Will push v5.
Regards,
Krishna,
