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Subject: Re: [PATCH] xhci: print warning when HCE was set
To:     Mathias Nyman <mathias.nyman@linux.intel.com>,
        <gregkh@linuxfoundation.org>, <mathias.nyman@intel.com>
CC:     <linux-usb@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <yisen.zhuang@huawei.com>
References: <20220915011134.58400-1-liulongfang@huawei.com>
 <6b5a45f1-caf3-4259-77da-e36788f5b8a9@linux.intel.com>
From:   liulongfang <liulongfang@huawei.com>
Message-ID: <2648444c-2f2a-4d9b-8545-6677663adcf0@huawei.com>
Date:   Sat, 24 Sep 2022 10:35:33 +0800
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On 2022/9/22 21:01, Mathias Nyman Wrote:
> Hi
> 
> On 15.9.2022 4.11, Longfang Liu wrote:
>> When HCE(Host Controller Error) is set, it means that the xhci hardware
>> controller has an error at this time, but the current xhci driver
>> software does not log this event.
>>
>> By adding an HCE event detection in the xhci interrupt processing
>> interface, a warning log is output to the system, which is convenient
>> for system device status tracking.
>>
> 
> xHC should cease all activity when it sets HCE, and is probably not
> generating interrupts anymore.
> 
> Would probably be more useful to check for HCE at timeouts than in the
> interrupt handler.
> 

Which function of the driver code is this timeout in?

> If this is something seen on actual hardware then it makes sense to add it.
> 

This HCE error is sure to report an interrupt on the chip we are using.

> Thanks
> -Mathias
> .
> 
Thansk,
Longfang.