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drivers/misc/apds9802als.c: add runtime PM support
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Update the driver for the needed runtime power features.  Remove the old
user controlled power functions.

[[email protected]: put PM code under CONFIG_PM]
Signed-off-by: Hong Liu <[email protected]>
Signed-off-by: Alan Cox <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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@hongliu68 @torvalds
hongliu68 authored and torvalds committed Oct 26, 2010
1 parent 22d96aa commit f0cfec1
Showing 1 changed file with 103 additions and 64 deletions.
167 changes: 103 additions & 64 deletions drivers/misc/apds9802als.c
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Original file line number Diff line number Diff line change
Expand Up @@ -29,19 +29,16 @@
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
#include <linux/hwmon-sysfs.h>
#include <linux/pm_runtime.h>

#define ALS_MIN_RANGE_VAL 1
#define ALS_MAX_RANGE_VAL 2
#define POWER_STA_ENABLE 1
#define POWER_STA_DISABLE 0
#define APDS9802ALS_I2C_ADDR 0x29

#define DRIVER_NAME "apds9802als"

struct als_data {
struct device *hwmon_dev;
bool needresume;
struct mutex mutex;
};

Expand All @@ -60,29 +57,64 @@ static ssize_t als_sensing_range_show(struct device *dev,
return sprintf(buf, "65535\n");
}

static int als_wait_for_data_ready(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
int ret;
int retry = 10;

do {
msleep(30);
ret = i2c_smbus_read_byte_data(client, 0x86);
} while (!(ret & 0x80) && retry--);

if (!retry) {
dev_warn(dev, "timeout waiting for data ready\n");
return -ETIMEDOUT;
}

return 0;
}

static ssize_t als_lux0_input_data_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct als_data *data = i2c_get_clientdata(client);
unsigned int ret_val;
int ret_val;
int temp;

/* Protect against parallel reads */
pm_runtime_get_sync(dev);
mutex_lock(&data->mutex);
temp = i2c_smbus_read_byte_data(client, 0x8C);/*LSB data*/

/* clear EOC interrupt status */
i2c_smbus_write_byte(client, 0x40);
/* start measurement */
temp = i2c_smbus_read_byte_data(client, 0x81);
i2c_smbus_write_byte_data(client, 0x81, temp | 0x08);

ret_val = als_wait_for_data_ready(dev);
if (ret_val < 0)
goto failed;

temp = i2c_smbus_read_byte_data(client, 0x8C); /* LSB data */
if (temp < 0) {
ret_val = temp;
goto failed;
}
ret_val = i2c_smbus_read_byte_data(client, 0x8D);/*MSB data*/
ret_val = i2c_smbus_read_byte_data(client, 0x8D); /* MSB data */
if (ret_val < 0)
goto failed;

mutex_unlock(&data->mutex);
ret_val = (ret_val << 8) | temp;
return sprintf(buf, "%d\n", ret_val);
pm_runtime_put_sync(dev);

temp = (ret_val << 8) | temp;
return sprintf(buf, "%d\n", temp);
failed:
mutex_unlock(&data->mutex);
pm_runtime_put_sync(dev);
return ret_val;
}

Expand All @@ -104,9 +136,10 @@ static ssize_t als_sensing_range_store(struct device *dev,
else
return -ERANGE;

pm_runtime_get_sync(dev);

/* Make sure nobody else reads/modifies/writes 0x81 while we
are active */

mutex_lock(&data->mutex);

ret_val = i2c_smbus_read_byte_data(client, 0x81);
Expand All @@ -116,34 +149,25 @@ static ssize_t als_sensing_range_store(struct device *dev,
/* Reset the bits before setting them */
ret_val = ret_val & 0xFA;

if (val == 1) /* Setting the continous measurement up to 4k LUX */
ret_val = (ret_val | 0x05);
else /* Setting the continous measurement up to 64k LUX*/
ret_val = (ret_val | 0x04);
if (val == 1) /* Setting detection range up to 4k LUX */
ret_val = (ret_val | 0x01);
else /* Setting detection range up to 64k LUX*/
ret_val = (ret_val | 0x00);

ret_val = i2c_smbus_write_byte_data(client, 0x81, ret_val);

if (ret_val >= 0) {
/* All OK */
mutex_unlock(&data->mutex);
pm_runtime_put_sync(dev);
return count;
}
fail:
mutex_unlock(&data->mutex);
pm_runtime_put_sync(dev);
return ret_val;
}

static ssize_t als_power_status_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
int ret_val;
ret_val = i2c_smbus_read_byte_data(client, 0x80);
if (ret_val < 0)
return ret_val;
ret_val = ret_val & 0x01;
return sprintf(buf, "%d\n", ret_val);
}

static int als_set_power_state(struct i2c_client *client, bool on_off)
{
int ret_val;
Expand All @@ -163,39 +187,13 @@ static int als_set_power_state(struct i2c_client *client, bool on_off)
return ret_val;
}

static ssize_t als_power_status_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct als_data *data = i2c_get_clientdata(client);
unsigned long val;
int ret_val;

if (strict_strtoul(buf, 10, &val))
return -EINVAL;
if (val == POWER_STA_ENABLE) {
ret_val = als_set_power_state(client, true);
data->needresume = true;
} else if (val == POWER_STA_DISABLE) {
ret_val = als_set_power_state(client, false);
data->needresume = false;
} else
return -EINVAL;
if (ret_val < 0)
return ret_val;
return count;
}

static DEVICE_ATTR(lux0_sensor_range, S_IRUGO | S_IWUSR,
als_sensing_range_show, als_sensing_range_store);
static DEVICE_ATTR(lux0_input, S_IRUGO, als_lux0_input_data_show, NULL);
static DEVICE_ATTR(power_state, S_IRUGO | S_IWUSR,
als_power_status_show, als_power_status_store);

static struct attribute *mid_att_als[] = {
&dev_attr_lux0_sensor_range.attr,
&dev_attr_lux0_input.attr,
&dev_attr_power_state.attr,
NULL
};

Expand All @@ -213,15 +211,21 @@ static int als_set_default_config(struct i2c_client *client)
dev_err(&client->dev, "failed default switch on write\n");
return ret_val;
}
/* Continous from 1Lux to 64k Lux */
ret_val = i2c_smbus_write_byte_data(client, 0x81, 0x04);
/* detection range: 1~64K Lux, maunal measurement */
ret_val = i2c_smbus_write_byte_data(client, 0x81, 0x08);
if (ret_val < 0)
dev_err(&client->dev, "failed default LUX on write\n");

/* We always get 0 for the 1st measurement after system power on,
* so make sure it is finished before user asks for data.
*/
als_wait_for_data_ready(&client->dev);

return ret_val;
}

static int apds9802als_probe(struct i2c_client *client,
const struct i2c_device_id *id)
static int apds9802als_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int res;
struct als_data *data;
Expand All @@ -237,11 +241,14 @@ static int apds9802als_probe(struct i2c_client *client,
dev_err(&client->dev, "device create file failed\n");
goto als_error1;
}
dev_info(&client->dev,
"%s apds9802als: ALS chip found\n", client->name);
dev_info(&client->dev, "ALS chip found\n");
als_set_default_config(client);
data->needresume = true;
mutex_init(&data->mutex);

pm_runtime_enable(&client->dev);
pm_runtime_get(&client->dev);
pm_runtime_put(&client->dev);

return res;
als_error1:
i2c_set_clientdata(client, NULL);
Expand All @@ -252,11 +259,14 @@ static int apds9802als_probe(struct i2c_client *client,
static int apds9802als_remove(struct i2c_client *client)
{
struct als_data *data = i2c_get_clientdata(client);

als_set_power_state(client, false);
sysfs_remove_group(&client->dev.kobj, &m_als_gr);
kfree(data);
return 0;
}

#ifdef CONFIG_PM
static int apds9802als_suspend(struct i2c_client *client, pm_message_t mesg)
{
als_set_power_state(client, false);
Expand All @@ -265,13 +275,42 @@ static int apds9802als_suspend(struct i2c_client *client, pm_message_t mesg)

static int apds9802als_resume(struct i2c_client *client)
{
struct als_data *data = i2c_get_clientdata(client);
als_set_default_config(client);

if (data->needresume == true)
als_set_power_state(client, true);
pm_runtime_get(&client->dev);
pm_runtime_put(&client->dev);
return 0;
}

static int apds9802als_runtime_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);

als_set_power_state(client, false);
return 0;
}

static int apds9802als_runtime_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);

als_set_power_state(client, true);
return 0;
}

static const struct dev_pm_ops apds9802als_pm_ops = {
.runtime_suspend = apds9802als_runtime_suspend,
.runtime_resume = apds9802als_runtime_resume,
};

#define APDS9802ALS_PM_OPS (&apds9802als_pm_ops)

#else /* CONFIG_PM */
#define apds9802als_suspend NULL
#define apds9802als_resume NULL
#define APDS9802ALS_PM_OPS NULL
#endif /* CONFIG_PM */

static struct i2c_device_id apds9802als_id[] = {
{ DRIVER_NAME, 0 },
{ }
Expand All @@ -281,8 +320,8 @@ MODULE_DEVICE_TABLE(i2c, apds9802als_id);

static struct i2c_driver apds9802als_driver = {
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
.name = DRIVER_NAME,
.pm = APDS9802ALS_PM_OPS,
},
.probe = apds9802als_probe,
.remove = apds9802als_remove,
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