hwmon: (nct7904) Add error handling in probe function.

When register read and write operations return errors, needs to add
error handling.

Signed-off-by: amy.shih <amy.shih@advantech.com.tw>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 18 insertions, 5 deletions

diff --git a/drivers/hwmon/nct7904.c b/drivers/hwmon/nct7904.c
index 5708171197e7..401ed4a4a576 100644
--- a/drivers/hwmon/nct7904.c
+++ b/drivers/hwmon/nct7904.c
@@ -506,6 +506,8 @@ static int nct7904_probe(struct i2c_client *client,
 
         /* CPU_TEMP attributes */
         ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL0_REG);
+        if (ret < 0)
+                return ret;
 
         if ((ret & 0x6) == 0x6)
                 data->tcpu_mask |= 1; /* TR1 */
@@ -518,11 +520,15 @@ static int nct7904_probe(struct i2c_client *client,
 
         /* LTD */
         ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
+        if (ret < 0)
+                return ret;
         if ((ret & 0x02) == 0x02)
                 data->tcpu_mask |= 0x10;
 
         /* Multi-Function detecting for Volt and TR/TD */
         ret = nct7904_read_reg(data, BANK_0, VT_ADC_MD_REG);
+        if (ret < 0)
+                return ret;
 
         for (i = 0; i < 4; i++) {
                 val = (ret & (0x03 << i)) >> (i * 2);
@@ -533,22 +539,29 @@ static int nct7904_probe(struct i2c_client *client,
 
         /* PECI */
         ret = nct7904_read_reg(data, BANK_2, PFE_REG);
+        if (ret < 0)
+                return ret;
         if (ret & 0x80) {
                 data->enable_dts = 1; //Enable DTS & PECI
         } else {
                 ret = nct7904_read_reg(data, BANK_2, TSI_CTRL_REG);
+                if (ret < 0)
+                        return ret;
                 if (ret & 0x80)
                         data->enable_dts = 0x3; //Enable DTS & TSI
         }
 
         /* Check DTS enable status */
         if (data->enable_dts) {
-                data->has_dts =
-                        nct7904_read_reg(data, BANK_0, DTS_T_CTRL0_REG) & 0xF;
+                ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL0_REG);
+                if (ret < 0)
+                        return ret;
+                data->has_dts = ret & 0xF;
                 if (data->enable_dts & 0x2) {
-                        data->has_dts |=
-                        (nct7904_read_reg(data, BANK_0, DTS_T_CTRL1_REG) & 0xF)
-                                                                << 4;
+                        ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL1_REG);
+                        if (ret < 0)
+                                return ret;
+                        data->has_dts |= (ret & 0xF) << 4;
                 }
         }