ASoC: cs43130: Use DEVICE_ATTR_RO macro

Use DEVICE_ATTR_RO() helper instead of plain DEVICE_ATTR(),
which makes the code a bit shorter and easier to read.

Signed-off-by: YueHaibing <[e-mail]>
Reviewed-by: Charles Keepax <[e-mail]>
Message-Id: <[e-mail]>
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/codecs/cs43130.c

···
 				 cs43130->hpload_dc[ch]);
 }
 
-static ssize_t cs43130_show_dc_l(struct device *dev,
-				 struct device_attribute *attr, char *buf)
+static ssize_t hpload_dc_l_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
 	return cs43130_show_dc(dev, buf, HP_LEFT);
 }
 
-static ssize_t cs43130_show_dc_r(struct device *dev,
-				 struct device_attribute *attr, char *buf)
+static ssize_t hpload_dc_r_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
 	return cs43130_show_dc(dev, buf, HP_RIGHT);
 }
···
 	}
 }
 
-static ssize_t cs43130_show_ac_l(struct device *dev,
-				 struct device_attribute *attr, char *buf)
+static ssize_t hpload_ac_l_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
 	return cs43130_show_ac(dev, buf, HP_LEFT);
 }
 
-static ssize_t cs43130_show_ac_r(struct device *dev,
-				 struct device_attribute *attr, char *buf)
+static ssize_t hpload_ac_r_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
 	return cs43130_show_ac(dev, buf, HP_RIGHT);
 }
 
-static DEVICE_ATTR(hpload_dc_l, 0444, cs43130_show_dc_l, NULL);
-static DEVICE_ATTR(hpload_dc_r, 0444, cs43130_show_dc_r, NULL);
-static DEVICE_ATTR(hpload_ac_l, 0444, cs43130_show_ac_l, NULL);
-static DEVICE_ATTR(hpload_ac_r, 0444, cs43130_show_ac_r, NULL);
+static DEVICE_ATTR_RO(hpload_dc_l);
+static DEVICE_ATTR_RO(hpload_dc_r);
+static DEVICE_ATTR_RO(hpload_ac_l);
+static DEVICE_ATTR_RO(hpload_ac_r);
 
 static struct reg_sequence hp_en_cal_seq[] = {
 	{CS43130_INT_MASK_4, CS43130_INT_MASK_ALL},