[ARM] 5141/1: PWM: pwm_request() should return an PTR_ERR() instead of NULL.

Make the return of pwm_request() be more informative than just
being NULL on error by using PTR_ERR() to respond with an
approriate error.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 11 insertions, 5 deletions

diff --git a/arch/arm/mach-pxa/pwm.c b/arch/arm/mach-pxa/pwm.c
index 7c86dd1d108f..ce28cd9fed16 100644
--- a/arch/arm/mach-pxa/pwm.c
+++ b/arch/arm/mach-pxa/pwm.c
@@ -119,17 +119,23 @@ struct pwm_device *pwm_request(int pwm_id, const char *label)
         mutex_lock(&pwm_lock);
 
         list_for_each_entry(pwm, &pwm_list, node) {
-                if (pwm->pwm_id == pwm_id && pwm->use_count == 0) {
-                        pwm->use_count++;
-                        pwm->label = label;
+                if (pwm->pwm_id == pwm_id) {
                         found = 1;
                         break;
                 }
         }
 
-        mutex_unlock(&pwm_lock);
+        if (found) {
+                if (pwm->use_count == 0) {
+                        pwm->use_count++;
+                        pwm->label = label;
+                } else
+                        pwm = ERR_PTR(-EBUSY);
+        } else
+                pwm = ERR_PTR(-ENOENT);
 
-        return (found) ? pwm : NULL;
+        mutex_unlock(&pwm_lock);
+        return pwm;
 }
 EXPORT_SYMBOL(pwm_request);