iio: trigger: free trigger resource correctly
authorAlison Schofield <amsfield22@gmail.com>
Fri, 20 Jan 2017 03:47:38 +0000 (19:47 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 15 Nov 2017 16:13:10 +0000 (17:13 +0100)
commit079822da0a00284aba8968f19d1579dd77140b8d
treeffd70babedf8f251e06c20be7c35a57885f87ca8
parent26fa336d69a227061d7396f1d225a4cec8e292af
iio: trigger: free trigger resource correctly

[ Upstream commit 10e840dfb0b7fc345082dd9e5fff3c1c02e7690e ]

These stand-alone trigger drivers were using iio_trigger_put()
where they should have been using iio_trigger_free().  The
iio_trigger_put() adds a module_put which is bad since they
never did a module_get.

In the sysfs driver, module_get/put's are used as triggers are
added & removed. This extra module_put() occurs on an error path
in the probe routine (probably rare).

In the bfin-timer & interrupt trigger drivers, the module resources
are not explicitly managed, so it's doing a put on something that
was never get'd.  It occurs on the probe error path and on the
remove path (not so rare).

Tested with the sysfs trigger driver.
The bfin & interrupt drivers were build tested & inspected only.

Signed-off-by: Alison Schofield <amsfield22@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/iio/trigger/iio-trig-interrupt.c
drivers/iio/trigger/iio-trig-sysfs.c
drivers/staging/iio/trigger/iio-trig-bfin-timer.c