Re: [PATCH 1/1] driver,usb: Fix a warning in uhci-hcd driver

ZhenHua
2013-04-23T23:56:14Z

On 04/23/2013 10:07 PM, Greg KH wrote:
> On Tue, Apr 23, 2013 at 03:15:01PM +0800, Li, Zhen-Hua wrote:
>> From: "Li, Zhen-Hua" <zhen-hual@hp.com>
>>
>> This patch is trying to fix bug QXCR1001261767.
Sorry for the bug number. Please ignore this line.

> What is that bug number? Where can it be referenced? If you are going
> to put it in a public place (like a kernel changelog), it needs to be
> publicly accessible.
>
>> On some HP platform, when usb driver inits the iLo Virtual USB Controller, there may be a warning "Controller not stopped yet!". It is because driver does not wait enough time.
> What happened to your line endings?
>
>> This patch adds more time waiting and retries.
> Why not only do this for your device?
>
>> Signed-off-by: Li, Zhen-Hua <zhen-hual@hp.com>
>> ---
>> drivers/usb/host/uhci-hcd.c | 16 +++++++++++++++-
>> 1 file changed, 15 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c
>> index 4a86b63..514e9d7 100644
>> --- a/drivers/usb/host/uhci-hcd.c
>> +++ b/drivers/usb/host/uhci-hcd.c
>> @@ -277,6 +277,9 @@ static int global_suspend_mode_is_broken(struct uhci_hcd *uhci)
>> uhci->global_suspend_mode_is_broken(uhci) : 0;
>> }
>>
>> +#define UHCI_SUSPENDRH_RETRY_MAX 10
>> +#define UHCI_SUSPENDRH_RETRY_DELAY 100
>> +
>> static void suspend_rh(struct uhci_hcd *uhci, enum uhci_rh_state new_state)
>> __releases(uhci->lock)
>> __acquires(uhci->lock)
>> @@ -284,6 +287,7 @@ __acquires(uhci->lock)
>> int auto_stop;
>> int int_enable, egsm_enable, wakeup_enable;
>> struct usb_device *rhdev = uhci_to_hcd(uhci)->self.root_hub;
>> + u16 try, stopped;
>>
>> auto_stop = (new_state == UHCI_RH_AUTO_STOPPED);
>> dev_dbg(&rhdev->dev, "%s%s\n", __func__,
>> @@ -355,7 +359,17 @@ __acquires(uhci->lock)
>> if (uhci->dead)
>> return;
>> }
>> - if (!(uhci_readw(uhci, USBSTS) & USBSTS_HCH))
>> +
>> + for (try = 0; try < UHCI_SUSPENDRH_RETRY_MAX; try++) {
>> + /*
>> + * Sometimes we may need to wait more time and try again.
>> + */
> "Sometimes"? Please be more specific. Also, a multi-line comment isn't
> needed, make it one line please.
>
> thanks,
>
> greg k-h