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>
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);
pb->notify = data->notify;
pb->pwm = pwm_request(data->pwm_id, "backlight");
- if (pb->pwm == NULL) {
+ if (IS_ERR(pb->pwm)) {
dev_err(&pdev->dev, "unable to request PWM for backlight\n");
- ret = -EBUSY;
+ ret = PTR_ERR(pb->pwm);
goto err_pwm;
}