+static ssize_t wf_show_control(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct wf_control *ctrl = container_of(attr, struct wf_control, attr);
+ s32 val = 0;
+ int err;
+
+ err = ctrl->ops->get_value(ctrl, &val);
+ if (err < 0)
+ return err;
+ return sprintf(buf, "%d\n", val);
+}
+
+/* This is really only for debugging... */
+static ssize_t wf_store_control(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct wf_control *ctrl = container_of(attr, struct wf_control, attr);
+ int val;
+ int err;
+ char *endp;
+
+ val = simple_strtoul(buf, &endp, 0);
+ while (endp < buf + count && (*endp == ' ' || *endp == '\n'))
+ ++endp;
+ if (endp - buf < count)
+ return -EINVAL;
+ err = ctrl->ops->set_value(ctrl, val);
+ if (err < 0)
+ return err;
+ return count;
+}
+