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Date:   Fri, 21 Apr 2023 18:59:18 +0800
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Subject: =?UTF-8?Q?Re=3a_=5bPATCH=5d_UHCI=ef=bc=9aadjust_zhaoxin_UHCI_contro?=
 =?UTF-8?Q?llers_OverCurrent_bit_value?=
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To:     Alan Stern <stern@rowland.harvard.edu>
CC:     <gregkh@linuxfoundation.org>, <linux-usb@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <tonywwang@zhaoxin.com>,
        <weitaowang@zhaoxin.com>
References: <20230420111445.5028-1-WeitaoWang-oc@zhaoxin.com>
 <95017e76-d029-4e55-af4f-4c7be0a14576@rowland.harvard.edu>
From:   "WeitaoWang-oc@zhaoxin.com" <WeitaoWang-oc@zhaoxin.com>
In-Reply-To: <95017e76-d029-4e55-af4f-4c7be0a14576@rowland.harvard.edu>
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On 2023/4/20 22:49, Alan Stern wrote:
> On Thu, Apr 20, 2023 at 07:14:45PM +0800, Weitao Wang wrote:
>> Over Current condition is not standardized in the UHCI spec.
>> Zhaoxin UHCI controllers report OverCurrent bit active off.
>> Intel controllers report it active on, so we'll adjust the bit value.
> 
> The last sentence is irrelevant.  You should say instead that the
> uhci-hcd driver needs to be told to expect the active-off behavior.

Okay, I'll change this description.Thanks!

>>
>> Signed-off-by: Weitao Wang <WeitaoWang-oc@zhaoxin.com>
>> ---
>>   drivers/usb/host/uhci-pci.c | 4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/drivers/usb/host/uhci-pci.c b/drivers/usb/host/uhci-pci.c
>> index 3592f757fe05..177e3c2aa287 100644
>> --- a/drivers/usb/host/uhci-pci.c
>> +++ b/drivers/usb/host/uhci-pci.c
>> @@ -126,6 +126,10 @@ static int uhci_pci_init(struct usb_hcd *hcd)
>>   	if (to_pci_dev(uhci_dev(uhci))->vendor == PCI_VENDOR_ID_VIA)
>>   		uhci->oc_low = 1;
>>   
>> +	/* ZHAOXIN controllers report OverCurrent bit active off. */
>> +	if (to_pci_dev(uhci_dev(uhci))->vendor == PCI_VENDOR_ID_ZHAOXIN)
>> +		uhci->oc_low = 1;
> 
> This is really just a matter of taste, but IMO it would be better to
> combine this comment and test with the preceding one.  Something like:

This advice is good and the code looks more concise.
I'll change these code and description in next patch version.

Thanks,
Weitao
> 	/*
> 	 * Intel controllers report the OverCurrent bit active on.  VIA
> 	 * and ZHAOXIN controllers report it active off, so we'll adjust
> 	 * the bit value.  (It's not standardized in the UHCI spec.)
> 	 */
> 	if (to_pci_dev(uhci_dev(uhci))->vendor == PCI_VENDOR_ID_VIA ||
> 	    to_pci_dev(uhci_dev(uhci))->vendor == PCI_VENDOR_ID_ZHAOXIN)
> 		uhci->oc_low = 1;
> 
> Alan Stern
> .