Bluetooth Power Management question

"Davide Bertola" <[email protected]>
Newsgroups gmane.linux.bluez.user
Message-ID <[email protected]>
---------- Forwarded message ----------
From: Davide Bertola <[email protected]>
Date: Thu, Apr 3, 2008 at 12:27 PM
Subject: bluetooth question
To: [email protected]


Hi,
I'm Davide from Italy.
I'm a Ubuntu Linux user (Hardy). My hardware is a Macbook (1,1) first
generation.
I'm investigating why power battery life is so different usin osx (4.5/5
hours)
or using linux (3/3.5 hours) [times are tested, not acpi estimated].

So this is my question.

My macbook has bluetooth connected to usb 1-4 (uhci) and I see something
strange.
When bluetooth.ko is loaded and hci0 is UP powertop shows that usb 1-4 wakes
up
the cpu 100/140 times, and cpu is in c0 state for about 2% - 3% of the time.

If I type "sudo hciconfig hci0 down" all those wakeups due to usb 1-4
disappear,
and the cpu goes in c0 for only 0.4% of the time.

If I also boot without loading bluetooth at all, my bluetooth mouse WORKS
in
a sort of usb emulation. It's seen as standard usb mouse. This way I can use
the
bt mouse without generating all those wakeups and cpu load. This reduce
power
consumption from 0.5 to 1W.

So it seems to me that bluetooth module does a lot of work that is not
necessary.
Why all those wakeups and cpu load?

The bluetooth adapter is from Cambridge Silicon Radio, like the powerbook
ones.

-------------------------------------------------------------------------
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace

_______________________________________________
Bluez-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/bluez-users
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.