2007-08-03 16:57:39

by Adam Kropelin

[permalink] [raw]
Subject: Re: [linux-usb-devel] [PATCH] USB: Only enable autosuspend by default on certain device classes

Dave Jones wrote:
> On Fri, Aug 03, 2007 at 05:31:52PM +0200, Jiri Kosina wrote:
>
>>> Plus if you're connected to such a device for monitoring purposes
>>> you're probably powered by it as well, so you have little to gain
>>> from suspend even if it works.
>>
>> I currently don't have any HID UPS by hand to verify, but I'd be
>> surprised if they would advertise remote wakeup capability ... ?
>
> Looks like mine does..
> [...]
> idVendor 0x051d American Power Conversion
> idProduct 0x0002 Back-UPS Pro 500/1000/1500

*notes to self to send pci.ids patch again*

> bcdDevice 1.06
> iManufacturer 3 APC
> iProduct 1 Back-UPS ES 500 FW:801.e6.D USB FW:e6

Yup, I have one of those in my arsenal and see the same thing.

> iSerial 2 AB0530291763
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 34
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0xe0
> Self Powered
> Remote Wakeup

I have reports of APC UPS remote wakeup working properly on "recent"
PowerMac G5s running OS X, but was never able to duplicate that success
on my cruddy old G3. I never figured out if it was a deficiency of the
UPS, the G3, or the OS. So it is possible that with appropriate OS
support this feature may actually work on certain UPSes (APC has a habit
of messing up the firmware differently on each model, so it's likely
hit-or-miss, but they are improving).

--Adam