Hi, Baolin Wang <baolin.wang@xxxxxxxxxx> writes: >>>> I'm thinking this is a bug in configfs interface of Gadget API, not >>>> dwc3. The only reason for this to happen would be if we get to >>>> ->udc_stop() with endpoints still enabled. >>>> >>>> Can you check if that's the case? i.e. can you check if any endpoints >>>> are still enabled when we get here? >>> >>> No, it is not any endpoints are still enabled. Like I said in commit >>> message, we will start end transfer command when disable the endpoint, >>> if the end transfer command complete event comes after we have freed >>> the gadget irq, it will trigger the interrupt line all the time to >>> crash the system. >> >> I see what the problem is. Databook tells us we *must* set CMDIOC when >> issuing EndTransfer command and we should always wait for Command >> Complete IRQ. However, we took a shortcut and just delayed for 100us >> after issuing End Transfer. > > Yes, but 100us delay is not enough in some scenarios, like changing > function with configfs frequently, we will met problems. heh, 100us *is* enough. However we still get an IRQ because we requested for it. If you want to fix this, then you need to find a way to get rid of that 100us udelay() and add a proper wait_for_completion() to delay execution until command complete IRQ fires up. -- balbi
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