[PATCH] PM / devfreq: return PTR_ERR not NULL in try_then_request_governor()

[Steven Price]

The callers of try_then_request_governor() only test for a PTR_ERR using
IS_ERR(). However in the case that request_module() fails then NULL is
currently returned which will cause a NULL-pointer dereference in the
caller.

Instead convert the error we already have to a valid PTR_ERR and return
it.

Fixes: 23c7b54ca1cd ("PM / devfreq: Fix devfreq_add_device() when drivers are 
built as modules.")
Signed-off-by: Steven Price <steven.pr...@arm.com>
---
 drivers/devfreq/devfreq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 0ae3de76833b..d29f66f0e52a 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -254,7 +254,7 @@ static struct devfreq_governor 
*try_then_request_governor(const char *name)
                /* Restore previous state before return */
                mutex_lock(&devfreq_list_lock);
                if (err)
-                       return NULL;
+                       return ERR_PTR(err);
 
                governor = find_devfreq_governor(name);
        }
-- 
2.20.1