Re: [PATCH v2 2/2] usb: dwc2: host: Clear interrupts before handling them

From: John Youn
Date: Thu Nov 19 2015 - 14:10:00 EST

On 11/19/2015 10:19 AM, Felipe Balbi wrote:
> Hi,
> Doug Anderson <dianders@xxxxxxxxxxxx> writes:
>>>>> isn't this a regression ? You're first clearing the interrupts and only
>>>>> then reading to check what's pending, however, what's pending has just
>>>>> been cleared. Seems like this should be:
>>>>> hprt0 = dwc2_readl(HPRT0);
>>>>> dwc2_writeal(PRTINT, GINTSTS);
>>>> Actually, we could probably remove the setting of GINTSTS_PRTINT
>>>> completely. The docs I have say that the GINTSTS_PRTINT is read only
>>>> and that:
>>>>> The core sets this bit to indicate a change in port status of one of the
>>>>> DWC_otg core ports in Host mode. The application must read the
>>>>> Host Port Control and Status (HPRT) register to determine the exact
>>>>> event that caused this interrupt. The application must clear the
>>>>> appropriate status bit in the Host Port Control and Status register to
>>>>> clear this bit.
>>>> writing PRTINT is probably useless, but John can confirm.
>>> Yup, it seems it can be removed.
>> How do you guys want this handled? Should I send up a new version of
>> this patch? ...or should I send a followon patch that does this
>> removal?
> I'll leave the final decision to John, but my opinion is that a new
> version of the patch would be preferrable.

Hi Doug,

Could you resend with the change?


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