[Bug 31468] High power drain during ACPI sleep

[rushi bhatt]

Public bug reported:
https://launchpad.net/malone/bugs/31468

Affects: linux-source-2.6.15 (Ubuntu)
       Severity: Normal
       Priority: (none set)
         Status: Unconfirmed

Description:
While suspending to RAM, certain Thinkpads with Radeon 7500 draw
excessive current (of the order of 3 watts on this R40 2722-6YU). The
problem has been traced to the radeon chip not going to a proper power
state.

More information can be found at

http://thinkwiki.org/wiki/Problem_with_high_power_drain_in_ACPI_sleep

Fedora Core 4 alredy ships with the patch mentioned at the above wiki,
and I have verified that a vanilla kernel.org patched with the above
brings the suspend to RAM power drain to an acceptable 700mW on dapper.

Would it be possible to ship this patch by default?

I understand radeonfb is discouraged in Ubuntu, but some people might be
able to take the risk and enable it to save some battery during sleep by
explicitly loading radeonfb.ko.