Re: converting appletouch to usb autosuspend...

Alistair John Strachan <[email protected]>
Newsgroups gmane.linux.kernel,gmane.linux.usb.devel
Message-ID <[email protected]>
On Saturday 12 May 2007 19:51:26 Soeren Sonnenburg wrote:
> Dear all,
>
> I've realized using the great powertop ( http://www.linuxpowertop.org/ )
> that loading the appletouch driver (and touching it once) makes consumes
> about 0.3 W even when not touching the pad. As rmmod'ing appletouch
> fixes this I wonder why the driver does not do this alone. So my
> question is what does one have to do to convert a driver (such as
> appletouch) to make use of usb autosuspend except for
>
>  .supports_autosuspend = 1
>
> ...
>
> While we are at it usb related powerhogs on this macbook pro are
> uhci_hcd (usb keyboard) and usb_hcd_poll_rh_status (rh_timer_func)
> too...

I've found that hci_usb also hogs power on the Macbook; blacklisting this 
module cuts down HZ considerably. I also found appletouch consumed ticks, 
just as you did.

uhci_hcd then drops to noise; my Macbook's sitting on 10W with the backlight 
on minimum, which is about what it can manage in OS X on maximum life 
settings.

-- 
Cheers,
Alistair.

Final year Computer Science undergraduate.
1F2 55 South Clerk Street, Edinburgh, UK.
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.