The SMU driver has a small mistake in the locking of the interrupt code,
if polled access and interrupt access race, interrupt may take a lock
and return without releasing it. This fixes it. With that patch, the
driver is rock solid with my experimental thermal control (which bangs
it pretty hard) racing with real time clock and cpufreq handling.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The SMU is the "system controller" chip used by Apple recent G5 machines
including the iMac G5. It drives things like fans, i2c busses, real time
clock, etc...
The current kernel contains a very crude driver that doesn't do much more
than reading the real time clock synchronously. This is a completely
rewritten driver that provides interrupt based command queuing, a userland
interface, and an i2c/smbus driver for accessing the devices hanging off
the SMU i2c busses like temperature sensors. This driver is a basic block
for upcoming work on thermal control for those machines, among others.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Benjamin Herrenschmidt
Linus Torvalds