RE: [PATCH] usb:cdns3: Fix for CV CH9 running with g_zero driver.

From: Pawel Laszczak
Date: Tue Oct 08 2019 - 23:59:36 EST


>Peter Chen <peter.chen@xxxxxxx> writes:
>> On 19-10-07 07:39:11, Pawel Laszczak wrote:
>>> Patch fixes issue with Halt Endnpoint Test observed
>> %s/Endnpoint/Endpoint
>>> during using g_zero
>>> driver as DUT. Bug occurred only on some testing board.
>> g_zero is legacy, please use configfs function source_sink or loopback
>> instead.
>We still want fixes for those ;-)

So, if my understanding is correct in new production systems
using legacy gadget drivers is not recommended and we are not going to fix
any more bugs there.

The legacy gadget drivers remains in the kernel only to support the old

So because we introduce new driver we should not worry about legacy
gadget drivers.

Is my understanding correct ?


>>> Endpoint can defer transition to Halted state if endpoint has pending
>>> requests.
>> The implementation of halt handling is a little complicated, you may
>> consider return -EAGAIN for functional stall through usb_ep_set_halt
>> from function driver if the requests are pending, it doesn't need to
>> defer such kinds of functional stall.
>-EAGAIN, IIRC is only supposed to be used for IN endpoint stalls.