[PATCH] usb: musb: dsps: handle the otg_state_a_wait_vrise_timeout case

Felipe Balbi balbi at ti.com
Tue Dec 8 07:16:59 PST 2015


Bin Liu <b-liu at ti.com> writes:
>>>>> "This bit should be set high prior to setting bit 0 and cleared after bit 0
>>>>> is cleared."
>>>>> and on the other side:
>>>>> "Both the soft_reset and soft_reset_isolation bits should be asserted
>>>>> simultaneously."
>>>>> The hang you saw could be explained by the following:
>>>>> "Setting only the soft_reset_isolation bit will cause all USB0 output
>>>>> signals to go to a known constant value via multiplexers.
>>>>> This will
>>>>> prevent future access to USB0."  page 2567
>>>> good catch. Setting them together makes the hang go away.
>>>> I still have the other problem, which is legacy IRQ reporting mode not
>>>> really working.
>>> I never tried to change the IRQ mapping. The 8 MUSB interrupt will be
>>> the same no matter where they are reported from. What do you expect when
>>> switch to the MUSB IRQ reporting mode?
>> read events from MUSB's registers instead of TI's :-) so, MUSB_INTRUSB,
> I meant you expect to see any different event when switch to MUSB IRQ 
> mode? The TI wrapper just reports the same 8 interrupt events. I don't 
> think you would get any difference.

still valid to make sure ;-)

> BTY, I think I miss some context here. This Gregory's patch is trying to 
> fix the OTG state machine problem in musb_dsps, which is replicated with 
> a cable without a device connected. But it also mentions about 
> non-compliant MSC devices. How are the thumb drives related to this OTG 
> state issue?

the problem seems to be caused by the missing disconnect IRQ. Not really
missing, but taking seconds to trigger.

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