hwmon: (pmbus_core) Simplify sign extensions

Shift operations can be used for sign extensions. Use it.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>

1 files changed, 4 insertions, 13 deletions

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 814ebb198346..00460d8d8423 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -445,13 +445,8 @@ static long pmbus_reg2data_linear(struct pmbus_data *data,
                 exponent = data->exponent;
                 mantissa = (u16) sensor->data;
         } else {                                /* LINEAR11 */
-                exponent = (sensor->data >> 11) & 0x001f;
-                mantissa = sensor->data & 0x07ff;
-
-                if (exponent > 0x0f)
-                        exponent |= 0xffe0;     /* sign extend exponent */
-                if (mantissa > 0x03ff)
-                        mantissa |= 0xfffff800; /* sign extend mantissa */
+                exponent = ((s16)sensor->data) >> 11;
+                mantissa = ((s16)((sensor->data & 0x7ff) << 5)) >> 5;
         }
 
         val = mantissa;
@@ -1628,7 +1623,7 @@ static void pmbus_find_attributes(struct i2c_client *client,
 static int pmbus_identify_common(struct i2c_client *client,
                                  struct pmbus_data *data)
 {
-        int vout_mode = -1, exponent;
+        int vout_mode = -1;
 
         if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE))
                 vout_mode = _pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE);
@@ -1642,11 +1637,7 @@ static int pmbus_identify_common(struct i2c_client *client,
                         if (data->info->format[PSC_VOLTAGE_OUT] != linear)
                                 return -ENODEV;
 
-                        exponent = vout_mode & 0x1f;
-                        /* and sign-extend it */
-                        if (exponent & 0x10)
-                                exponent |= ~0x1f;
-                        data->exponent = exponent;
+                        data->exponent = ((s8)(vout_mode << 3)) >> 3;
                         break;
                 case 1: /* VID mode         */
                         if (data->info->format[PSC_VOLTAGE_OUT] != vid)