Many IBM Thinkpad T4* models and some R* and X* with radeon video cards draw
too much power when suspended to RAM, reducing drastically the battery
lifetime. The solution is to enable suspend-to-D2 on these machines. They
are whitelisted through their subsystem vendor/device ID. This fixes
http://bugzilla.kernel.org/show_bug.cgi?id=3022
The patch introduces a framework to alter the pm_mode and reinit_func fields
of the radeonfb_info structure based on a whitelist. This should facilitate
future hardware-dependent workarounds. The workaround for the Samsung P35
that is already in the radeonfb code has been rewritten using this framework.
The behavior can be overridden with module options:
i) video=radeonfb:force_sleep=1
enable suspend-to-D2 also on non-whitelisted machines (useful for
testing new notebook models),
ii) video=radeonfb:ignore_devlist=1
Disable checking the whitelist and do not apply any workarounds.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
994aad251a