pinctrl: msm: Silence recursive lockdep warning

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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>

...

This commit is contained in:

Stephen Boyd 2014-03-06 22:44:40 -08:00 • committed by Linus Walleij

parent 3c7d563789

commit 3525f5556a

1 changed files with 7 additions and 0 deletions

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drivers/pinctrl/pinctrl-msm.c

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