[PATCH 3.2 48/94] staging:iio: trigger fixes for repeat request of same trigger and allocation failure

[Ben Hutchings]

3.2.82-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Jonathan Cameron <ji...@cam.ac.uk>

commit 5dd72ecb0166498852705939163f375d693d37f3 upstream.

Both of these are decidedly silly bugs show up whilst testing
completely different code paths.

Signed-off-by: Jonathan Cameron <ji...@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gre...@suse.de>
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
 drivers/staging/iio/industrialio-trigger.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

--- a/drivers/staging/iio/industrialio-trigger.c
+++ b/drivers/staging/iio/industrialio-trigger.c
@@ -222,8 +222,16 @@ static int iio_trigger_attach_poll_func(
        ret = request_threaded_irq(pf->irq, pf->h, pf->thread,
                                   pf->type, pf->name,
                                   pf);
-       if (trig->ops && trig->ops->set_trigger_state && notinuse)
+       if (ret < 0) {
+               module_put(pf->indio_dev->info->driver_module);
+               return ret;
+       }
+
+       if (trig->ops && trig->ops->set_trigger_state && notinuse) {
                ret = trig->ops->set_trigger_state(trig, true);
+               if (ret < 0)
+                       module_put(pf->indio_dev->info->driver_module);
+       }
 
        return ret;
 }
@@ -336,6 +344,8 @@ static ssize_t iio_trigger_write_current
        mutex_unlock(&indio_dev->mlock);
 
        trig = iio_trigger_find_by_name(buf, len);
+       if (oldtrig == trig)
+               return len;
 
        if (trig && indio_dev->info->validate_trigger) {
                ret = indio_dev->info->validate_trigger(indio_dev, trig);