[PATCH] hwmon: w83792d simplify in low bits handling

Simplify the way the w83792d driver handles the extra resolution
bits of voltage input channels.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Yuan Mu <Ymu@winbond.com.tw>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 10 insertions, 38 deletions

diff --git a/drivers/hwmon/w83792d.c b/drivers/hwmon/w83792d.c
index 0ad1ae569531..b176bf0c4c7b 100644
--- a/drivers/hwmon/w83792d.c
+++ b/drivers/hwmon/w83792d.c
@@ -281,7 +281,7 @@ struct w83792d_data {
         u8 in[9];               /* Register value */
         u8 in_max[9];           /* Register value */
         u8 in_min[9];           /* Register value */
-        u8 low_bits[2];         /* Additional resolution to voltage in0-6 */
+        u16 low_bits;           /* Additional resolution to voltage in6-0 */
         u8 fan[7];              /* Register value */
         u8 fan_min[7];          /* Register value */
         u8 temp1[3];            /* current, over, thyst */
@@ -323,38 +323,10 @@ static struct i2c_driver w83792d_driver = {
         .detach_client = w83792d_detach_client,
 };
 
-static long in_count_from_reg(int nr, struct w83792d_data *data)
+static inline long in_count_from_reg(int nr, struct w83792d_data *data)
 {
-        u16 vol_count = data->in[nr];
-        u16 low_bits = 0;
-        vol_count = (vol_count << 2);
-        switch (nr)
-        {
-        case 0:  /* vin0 */
-                low_bits = (data->low_bits[0]) & 0x03;
-                break;
-        case 1:  /* vin1 */
-                low_bits = ((data->low_bits[0]) & 0x0c) >> 2;
-                break;
-        case 2:  /* vin2 */
-                low_bits = ((data->low_bits[0]) & 0x30) >> 4;
-                break;
-        case 3:  /* vin3 */
-                low_bits = ((data->low_bits[0]) & 0xc0) >> 6;
-                break;
-        case 4:  /* vin4 */
-                low_bits = (data->low_bits[1]) & 0x03;
-                break;
-        case 5:  /* vin5 */
-                low_bits = ((data->low_bits[1]) & 0x0c) >> 2;
-                break;
-        case 6:  /* vin6 */
-                low_bits = ((data->low_bits[1]) & 0x30) >> 4;
-        default:
-                break;
-        }
-        vol_count = vol_count | low_bits;
-        return vol_count;
+        /* in7 and in8 do not have low bits, but the formula still works */
+        return ((data->in[nr] << 2) | ((data->low_bits >> (2 * nr)) & 0x03));
 }
 
 /* following are the sysfs callback functions */
@@ -1481,10 +1453,10 @@ static struct w83792d_data *w83792d_update_device(struct device *dev)
                         data->in_min[i] = w83792d_read_value(client,
                                                 W83792D_REG_IN_MIN[i]);
                 }
-                data->low_bits[0] = w83792d_read_value(client,
-                                                W83792D_REG_LOW_BITS1);
-                data->low_bits[1] = w83792d_read_value(client,
-                                                W83792D_REG_LOW_BITS2);
+                data->low_bits = w83792d_read_value(client,
+                                                W83792D_REG_LOW_BITS1) +
+                                 (w83792d_read_value(client,
+                                                W83792D_REG_LOW_BITS2) << 8);
                 for (i = 0; i < 7; i++) {
                         /* Update the Fan measured value and limits */
                         data->fan[i] = w83792d_read_value(client,
@@ -1596,8 +1568,8 @@ static void w83792d_print_debug(struct w83792d_data *data, struct device *dev)
                 dev_dbg(dev, "vin[%d] max is: 0x%x\n", i, data->in_max[i]);
                 dev_dbg(dev, "vin[%d] min is: 0x%x\n", i, data->in_min[i]);
         }
-        dev_dbg(dev, "Low Bit1 is: 0x%x\n", data->low_bits[0]);
-        dev_dbg(dev, "Low Bit2 is: 0x%x\n", data->low_bits[1]);
+        dev_dbg(dev, "Low Bit1 is: 0x%x\n", data->low_bits & 0xff);
+        dev_dbg(dev, "Low Bit2 is: 0x%x\n", data->low_bits >> 8);
         dev_dbg(dev, "7 set of Fan Counts and Duty Cycles: =====>\n");
         for (i=0; i<7; i++) {
                 dev_dbg(dev, "fan[%d] is: 0x%x\n", i, data->fan[i]);