Seeing the following every time the CPU enters or leaves idle on a
Beagleboard:
BUG: sleeping function called from invalid context at kernel/mutex.c:269
in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/0
no locks held by swapper/0/0.
[<c001659c>] (unwind_backtrace+0x0/0xf8) from [<c05aaa7c>] (mutex_lock_nested+0x24/0x380)
[<c05aaa7c>] (mutex_lock_nested+0x24/0x380) from [<c043bd1c>] (ledtrig_cpu+0x38/0x88)
[<c043bd1c>] (ledtrig_cpu+0x38/0x88) from [<c000f4b0>] (cpu_idle+0xf4/0x120)
[<c000f4b0>] (cpu_idle+0xf4/0x120) from [<c07e47c8>] (start_kernel+0x2bc/0x30c)
Miles Lane has reported seeing similar splats during system suspend.
The mutex in struct led_trigger_cpu appears to have no function: it
resides in a per-cpu data structure which never changes after the
trigger is registered. So just remove it.
Reported-by: Miles Lane <miles.lane@gmail.com>
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Bryan Wu <roc@roc-samos.(none)>
Attempting to consolidate the ARM LED code, this removes the
custom RealView LED trigger code to turn LEDs on and off in
response to CPU activity and replace it with a standard trigger.
(bryan.wu@canonical.com:
It introduces several syscore stubs into this trigger.
It also provides ledtrig_cpu trigger event stub in <linux/leds.h>.
Although it was inspired by ARM work, it can be used in other arch.)
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Reviewed-by: Jamie Iles <jamie@jamieiles.com>
Tested-by: Jochen Friedrich <jochen@scram.de>
Nathan Lynch