diff options
Diffstat (limited to 'drivers/misc/apds9802als.c')
| -rw-r--r-- | drivers/misc/apds9802als.c | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/drivers/misc/apds9802als.c b/drivers/misc/apds9802als.c new file mode 100644 index 000000000..a32431f4b --- /dev/null +++ b/drivers/misc/apds9802als.c @@ -0,0 +1,309 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * apds9802als.c - apds9802 ALS Driver + * + * Copyright (C) 2009 Intel Corp + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + */ + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/err.h> +#include <linux/delay.h> +#include <linux/mutex.h> +#include <linux/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 DRIVER_NAME "apds9802als" + +struct als_data { + struct mutex mutex; +}; + +static ssize_t als_sensing_range_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + int val; + + val = i2c_smbus_read_byte_data(client, 0x81); + if (val < 0) + return val; + if (val & 1) + return sprintf(buf, "4095\n"); + else + 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 < 0) { + 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); + int ret_val; + int temp; + + /* Protect against parallel reads */ + pm_runtime_get_sync(dev); + mutex_lock(&data->mutex); + + /* 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 */ + if (ret_val < 0) + goto failed; + + mutex_unlock(&data->mutex); + 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; +} + +static ssize_t als_sensing_range_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); + int ret_val; + unsigned long val; + + ret_val = kstrtoul(buf, 10, &val); + if (ret_val) + return ret_val; + + if (val < 4096) + val = 1; + else if (val < 65536) + val = 2; + 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); + if (ret_val < 0) + goto fail; + + /* Reset the bits before setting them */ + ret_val = ret_val & 0xFA; + + 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 int als_set_power_state(struct i2c_client *client, bool on_off) +{ + int ret_val; + struct als_data *data = i2c_get_clientdata(client); + + mutex_lock(&data->mutex); + ret_val = i2c_smbus_read_byte_data(client, 0x80); + if (ret_val < 0) + goto fail; + if (on_off) + ret_val = ret_val | 0x01; + else + ret_val = ret_val & 0xFE; + ret_val = i2c_smbus_write_byte_data(client, 0x80, ret_val); +fail: + mutex_unlock(&data->mutex); + return ret_val; +} + +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 struct attribute *mid_att_als[] = { + &dev_attr_lux0_sensor_range.attr, + &dev_attr_lux0_input.attr, + NULL +}; + +static const struct attribute_group m_als_gr = { + .name = "apds9802als", + .attrs = mid_att_als +}; + +static int als_set_default_config(struct i2c_client *client) +{ + int ret_val; + /* Write the command and then switch on */ + ret_val = i2c_smbus_write_byte_data(client, 0x80, 0x01); + if (ret_val < 0) { + dev_err(&client->dev, "failed default switch on write\n"); + return ret_val; + } + /* 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) +{ + int res; + struct als_data *data; + + data = kzalloc(sizeof(struct als_data), GFP_KERNEL); + if (data == NULL) { + dev_err(&client->dev, "Memory allocation failed\n"); + return -ENOMEM; + } + i2c_set_clientdata(client, data); + res = sysfs_create_group(&client->dev.kobj, &m_als_gr); + if (res) { + dev_err(&client->dev, "device create file failed\n"); + goto als_error1; + } + dev_info(&client->dev, "ALS chip found\n"); + als_set_default_config(client); + mutex_init(&data->mutex); + + pm_runtime_set_active(&client->dev); + pm_runtime_enable(&client->dev); + + return res; +als_error1: + kfree(data); + return res; +} + +static void apds9802als_remove(struct i2c_client *client) +{ + struct als_data *data = i2c_get_clientdata(client); + + pm_runtime_get_sync(&client->dev); + + als_set_power_state(client, false); + sysfs_remove_group(&client->dev.kobj, &m_als_gr); + + pm_runtime_disable(&client->dev); + pm_runtime_set_suspended(&client->dev); + pm_runtime_put_noidle(&client->dev); + + kfree(data); +} + +#ifdef CONFIG_PM + +static int apds9802als_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + als_set_power_state(client, false); + return 0; +} + +static int apds9802als_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + als_set_power_state(client, true); + return 0; +} + +static UNIVERSAL_DEV_PM_OPS(apds9802als_pm_ops, apds9802als_suspend, + apds9802als_resume, NULL); + +#define APDS9802ALS_PM_OPS (&apds9802als_pm_ops) + +#else /* CONFIG_PM */ +#define APDS9802ALS_PM_OPS NULL +#endif /* CONFIG_PM */ + +static const struct i2c_device_id apds9802als_id[] = { + { DRIVER_NAME, 0 }, + { } +}; + +MODULE_DEVICE_TABLE(i2c, apds9802als_id); + +static struct i2c_driver apds9802als_driver = { + .driver = { + .name = DRIVER_NAME, + .pm = APDS9802ALS_PM_OPS, + }, + .probe = apds9802als_probe, + .remove = apds9802als_remove, + .id_table = apds9802als_id, +}; + +module_i2c_driver(apds9802als_driver); + +MODULE_AUTHOR("Anantha Narayanan <Anantha.Narayanan@intel.com"); +MODULE_DESCRIPTION("Avago apds9802als ALS Driver"); +MODULE_LICENSE("GPL v2"); |