/* * apds9802als.c - apds9802 ALS Driver * * Copyright (C) 2009 Intel Corp * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * */ #include <linux/module.h> #include <linux/init.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) { 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; if (strict_strtoul(buf, 10, &val)) return -EINVAL; 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 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 int __devexit 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); return 0; } #ifdef CONFIG_PM static int apds9802als_suspend(struct i2c_client *client, pm_message_t mesg) { als_set_power_state(client, false); return 0; } static int apds9802als_resume(struct i2c_client *client) { als_set_default_config(client); 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 }, { } }; MODULE_DEVICE_TABLE(i2c, apds9802als_id); static struct i2c_driver apds9802als_driver = { .driver = { .name = DRIVER_NAME, .pm = APDS9802ALS_PM_OPS, }, .probe = apds9802als_probe, .remove = __devexit_p(apds9802als_remove), .suspend = apds9802als_suspend, .resume = apds9802als_resume, .id_table = apds9802als_id, }; static int __init sensor_apds9802als_init(void) { return i2c_add_driver(&apds9802als_driver); } static void __exit sensor_apds9802als_exit(void) { i2c_del_driver(&apds9802als_driver); } module_init(sensor_apds9802als_init); module_exit(sensor_apds9802als_exit); MODULE_AUTHOR("Anantha Narayanan <Anantha.Narayanan@intel.com"); MODULE_DESCRIPTION("Avago apds9802als ALS Driver"); MODULE_LICENSE("GPL v2");