dm: power: Tidy up debugging output and return values

The currect PMIC debugging is a little confusing. Adjust it so that it is
clear whether the operation succeeded or failed. Also, avoid creating a new
error return value when a perfectly good one is already available.

Signed-off-by: Simon Glass <sjg@chromium.org>

drivers/power/pmic/pmic-uclass.c

@@ -133,8 +133,9 @@ int pmic_reg_read(struct udevice *dev, uint reg)
 	u8 byte;
 	int ret;
 
+	debug("%s: reg=%x", __func__, reg);
 	ret = pmic_read(dev, reg, &byte, 1);
-	debug("%s: reg=%x, value=%x\n", __func__, reg, byte);
+	debug(", value=%x, ret=%d\n", byte, ret);
 
 	return ret ? ret : byte;
 }
@@ -142,9 +143,13 @@ int pmic_reg_read(struct udevice *dev, uint reg)
 int pmic_reg_write(struct udevice *dev, uint reg, uint value)
 {
 	u8 byte = value;
+	int ret;
+
+	debug("%s: reg=%x, value=%x", __func__, reg, value);
+	ret = pmic_write(dev, reg, &byte, 1);
+	debug(", ret=%d\n", ret);
 
-	debug("%s: reg=%x, value=%x\n", __func__, reg, value);
-	return pmic_write(dev, reg, &byte, 1);
+	return ret;
 }
 
 int pmic_clrsetbits(struct udevice *dev, uint reg, uint clr, uint set)

drivers/power/pmic/rk808.c

@@ -30,9 +30,12 @@ static int rk808_reg_count(struct udevice *dev)
 static int rk808_write(struct udevice *dev, uint reg, const uint8_t *buff,
 			  int len)
 {
-	if (dm_i2c_write(dev, reg, buff, len)) {
+	int ret;
+
+	ret = dm_i2c_write(dev, reg, buff, len);
+	if (ret) {
 		debug("write error to device: %p register: %#x!", dev, reg);
-		return -EIO;
+		return ret;
 	}
 
 	return 0;
@@ -40,9 +43,12 @@ static int rk808_write(struct udevice *dev, uint reg, const uint8_t *buff,
 
 static int rk808_read(struct udevice *dev, uint reg, uint8_t *buff, int len)
 {
-	if (dm_i2c_read(dev, reg, buff, len)) {
+	int ret;
+
+	ret = dm_i2c_read(dev, reg, buff, len);
+	if (ret) {
 		debug("read error from device: %p register: %#x!", dev, reg);
-		return -EIO;
+		return ret;
 	}
 
 	return 0;

drivers/power/regulator/regulator-uclass.c

@@ -178,7 +178,7 @@ static void regulator_show(struct udevice *dev, int ret)
 		printf("; set %d uA", uc_pdata->min_uA);
 	printf("; enabling");
 	if (ret)
-		printf(" (ret: %d)\n", ret);
+		printf(" (ret: %d)", ret);
 	printf("\n");
 }