The alarm_en register is read each time the is_visible function is called.
Since it is a configuration register, this is completely unnecessary.
Read it once and cache its value.
Cc: Jean-Francois Dagenais <jeff.dagenais@xxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
v2: No change
drivers/hwmon/max6650.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c
index 90565318aafb..2edee4ca5cae 100644
--- a/drivers/hwmon/max6650.c
+++ b/drivers/hwmon/max6650.c
@@ -114,6 +114,7 @@ struct max6650_data {
u8 count;
u8 dac;
u8 alarm;
+ u8 alarm_en;
unsigned long cooling_dev_state;
};
@@ -545,8 +546,6 @@ static umode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a,
{
struct device *dev = container_of(kobj, struct device, kobj);
struct max6650_data *data = dev_get_drvdata(dev);
- struct i2c_client *client = data->client;
- u8 alarm_en = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN);
struct device_attribute *devattr;
/*
@@ -559,7 +558,7 @@ static umode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a,
|| devattr == &sensor_dev_attr_fan1_fault.dev_attr
|| devattr == &sensor_dev_attr_gpio1_alarm.dev_attr
|| devattr == &sensor_dev_attr_gpio2_alarm.dev_attr) {
- if (!(alarm_en & to_sensor_dev_attr(devattr)->index))
+ if (!(data->alarm_en & to_sensor_dev_attr(devattr)->index))
return 0;
}
@@ -682,6 +681,13 @@ static int max6650_init_client(struct max6650_data *data,
}
data->count = reg;
+ reg = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN);
+ if (reg < 0) {
+ dev_err(dev, "Failed to read alarm configuration, aborting.\n");
+ return reg;
+ }
+ data->alarm_en = reg;
+
if (!of_property_read_u32(client->dev.of_node, "maxim,fan-target-rpm",
&target_rpm)) {
max6650_set_target(data, target_rpm);
--
2.7.4
