Skip to content

Commit

Permalink
hwmon: (w83795) Delay reading pwm config registers
Browse files Browse the repository at this point in the history 
Wait until we need the pwm config register values, instead of
pre-reading them. This saves over 1 second on modprobe on my test
system.

Obviously this time is added when first accessing pwm config
attributes, however not everybody will use them, so it seems unfair
to slow down driver loading (and thus boot) for an optional feature.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
  • Loading branch information
Jean Delvare authored and Jean Delvare committed Oct 28, 2010
1 parent 2ae61de commit 1bb3450
Showing 1 changed file with 29 additions and 22 deletions.
51 changes: 29 additions & 22 deletions drivers/hwmon/w83795.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -372,6 +372,7 @@ struct w83795_data {

char valid;
char valid_limits;
char valid_pwm_config;
};

/*
Expand Down Expand Up @@ -503,11 +504,17 @@ static void w83795_update_limits(struct i2c_client *client)
data->valid_limits = 1;
}

static void w83795_update_pwm_config(struct i2c_client *client)
static struct w83795_data *w83795_update_pwm_config(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
int i, tmp;

mutex_lock(&data->update_lock);

if (data->valid_pwm_config)
goto END;

/* Read temperature source selection */
for (i = 0; i < ARRAY_SIZE(data->temp_src); i++)
data->temp_src[i] = w83795_read(client, W83795_REG_TSS(i));
Expand Down Expand Up @@ -556,6 +563,12 @@ static void w83795_update_pwm_config(struct i2c_client *client)
for (i = 0; i < ARRAY_SIZE(data->setup_pwm); i++)
data->setup_pwm[i] =
w83795_read(client, W83795_REG_SETUP_PWM(i));

data->valid_pwm_config = 1;

END:
mutex_unlock(&data->update_lock);
return data;
}

static struct w83795_data *w83795_update_device(struct device *dev)
Expand Down Expand Up @@ -775,13 +788,16 @@ store_fan_min(struct device *dev, struct device_attribute *attr,
static ssize_t
show_pwm(struct device *dev, struct device_attribute *attr, char *buf)
{
struct w83795_data *data = w83795_update_device(dev);
struct w83795_data *data;
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int nr = sensor_attr->nr;
int index = sensor_attr->index;
unsigned int val;

data = nr == PWM_OUTPUT ? w83795_update_device(dev)
: w83795_update_pwm_config(dev);

switch (nr) {
case PWM_STOP_TIME:
val = time_from_reg(data->pwm[index][nr]);
Expand Down Expand Up @@ -835,8 +851,7 @@ show_pwm_enable(struct device *dev, struct device_attribute *attr, char *buf)
{
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
int index = sensor_attr->index;
u8 tmp;

Expand Down Expand Up @@ -864,7 +879,7 @@ store_pwm_enable(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int index = sensor_attr->index;
Expand Down Expand Up @@ -905,8 +920,7 @@ show_temp_src(struct device *dev, struct device_attribute *attr, char *buf)
{
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
int index = sensor_attr->index;
u8 val = index / 2;
u8 tmp = data->temp_src[val];
Expand All @@ -926,7 +940,7 @@ store_temp_src(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int index = sensor_attr->index;
Expand Down Expand Up @@ -957,8 +971,7 @@ static ssize_t
show_temp_pwm_enable(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int nr = sensor_attr->nr;
Expand Down Expand Up @@ -986,7 +999,7 @@ store_temp_pwm_enable(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int nr = sensor_attr->nr;
Expand Down Expand Up @@ -1023,8 +1036,7 @@ store_temp_pwm_enable(struct device *dev, struct device_attribute *attr,
static ssize_t
show_fanin(struct device *dev, struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int nr = sensor_attr->nr;
Expand Down Expand Up @@ -1081,8 +1093,7 @@ store_fanin(struct device *dev, struct device_attribute *attr,
static ssize_t
show_temp_pwm(struct device *dev, struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int nr = sensor_attr->nr;
Expand Down Expand Up @@ -1143,8 +1154,7 @@ store_temp_pwm(struct device *dev, struct device_attribute *attr,
static ssize_t
show_sf4_pwm(struct device *dev, struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int nr = sensor_attr->nr;
Expand Down Expand Up @@ -1179,8 +1189,7 @@ store_sf4_pwm(struct device *dev, struct device_attribute *attr,
static ssize_t
show_sf4_temp(struct device *dev, struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int nr = sensor_attr->nr;
Expand Down Expand Up @@ -1456,8 +1465,7 @@ show_sf_setup(struct device *dev, struct device_attribute *attr, char *buf)
struct sensor_device_attribute_2 *sensor_attr =
to_sensor_dev_attr_2(attr);
int nr = sensor_attr->nr;
struct i2c_client *client = to_i2c_client(dev);
struct w83795_data *data = i2c_get_clientdata(client);
struct w83795_data *data = w83795_update_pwm_config(dev);
u16 val = data->setup_pwm[nr];

switch (nr) {
Expand Down Expand Up @@ -2029,7 +2037,6 @@ static int w83795_probe(struct i2c_client *client,
data->has_pwm = 8;
else
data->has_pwm = 2;
w83795_update_pwm_config(client);

err = w83795_handle_files(dev, device_create_file);
if (err)
Expand Down

0 comments on commit 1bb3450

Please sign in to comment.