drivers/misc/apds9802als.c: add runtime PM support

Update the driver for the needed runtime power features.  Remove the old
user controlled power functions.

[akpm@linux-foundation.org: put PM code under CONFIG_PM]
Signed-off-by: Hong Liu <hong.liu@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 103 insertions, 64 deletions

diff --git a/drivers/misc/apds9802als.c b/drivers/misc/apds9802als.c
index fbe49602f396..f9b91ba8900c 100644
--- a/drivers/misc/apds9802als.c
+++ b/drivers/misc/apds9802als.c
@@ -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;
 };
 
@@ -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;
 }
 
@@ -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);
@@ -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;
@@ -163,39 +187,13 @@ fail:
         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
 };
 
@@ -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;
@@ -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);
@@ -252,11 +259,14 @@ als_error1:
 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);
@@ -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 },
         { }
@@ -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,