hwmon: (w83795) Avoid reading the same register twice
Shorten driver load time by avoiding duplicate register access during
initialization. This saves 112 ms on modprobe on my test system.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/hwmon/w83795.c b/drivers/hwmon/w83795.c
index fd70a7b..aea3275 100644
--- a/drivers/hwmon/w83795.c
+++ b/drivers/hwmon/w83795.c
@@ -1986,6 +1986,9 @@
data->in[i][IN_READ] = tmp;
}
for (i = 0; i < IN_LSB_REG_NUM; i++) {
+ if ((i == 2 && data->chip_type == w83795adg) ||
+ (i >= 4 && !(data->has_in & (1 << (i + 11)))))
+ continue;
data->in_lsb[i][IN_MAX] =
w83795_read(client, IN_LSB_REG(i, IN_MAX));
data->in_lsb[i][IN_LOW] =
@@ -1995,13 +1998,17 @@
/* First update fan and limits */
for (i = 0; i < ARRAY_SIZE(data->fan); i++) {
+ /* Each register contains LSB for 2 fans, but we want to
+ * read it only once to save time */
+ if ((i & 1) == 0 && (data->has_fan & (3 << i)))
+ tmp = w83795_read(client, W83795_REG_FAN_MIN_LSB(i));
+
if (!(data->has_fan & (1 << i)))
continue;
data->fan_min[i] =
w83795_read(client, W83795_REG_FAN_MIN_HL(i)) << 4;
data->fan_min[i] |=
- (w83795_read(client, W83795_REG_FAN_MIN_LSB(i)) >>
- W83795_REG_FAN_MIN_LSB_SHIFT(i)) & 0x0F;
+ (tmp >> W83795_REG_FAN_MIN_LSB_SHIFT(i)) & 0x0F;
data->fan[i] = w83795_read(client, W83795_REG_FAN(i)) << 4;
data->fan[i] |=
(w83795_read(client, W83795_REG_VRLSB) >> 4) & 0x0F;
