If a driver calls enable_irq_wake() on a gpio turned interrupt
from the msm pinctrl driver we'll get a lockdep warning like so:
=============================================
[ INFO: possible recursive locking detected ]
3.14.0-rc3 #2 Not tainted
---------------------------------------------
modprobe/52 is trying to acquire lock:
(&irq_desc_lock_class){-.....}, at: [<c026aea0>] __irq_get_desc_lock+0x48/0x88
but task is already holding lock:
(&irq_desc_lock_class){-.....}, at: [<c026aea0>] __irq_get_desc_lock+0x48/0x88
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&irq_desc_lock_class);
lock(&irq_desc_lock_class);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by modprobe/52:
#0: (&__lockdep_no_validate__){......}, at: [<c04f2864>] __driver_attach+0x48/0x98
#1: (&__lockdep_no_validate__){......}, at: [<c04f2874>] __driver_attach+0x58/0x98
#2: (&irq_desc_lock_class){-.....}, at: [<c026aea0>] __irq_get_desc_lock+0x48/0x88
#3: (&(&pctrl->lock)->rlock){......}, at: [<c04bb4b8>] msm_gpio_irq_set_wake+0x20/0xa8
Silence it by putting the gpios into their own lock class.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
3525f5556a