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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * apds9802als.c - apds9802 ALS Driver4 *5 * Copyright (C) 2009 Intel Corp6 *7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~8 *9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~10 */11 12#include <linux/module.h>13#include <linux/slab.h>14#include <linux/i2c.h>15#include <linux/err.h>16#include <linux/delay.h>17#include <linux/mutex.h>18#include <linux/sysfs.h>19#include <linux/pm_runtime.h>20 21#define ALS_MIN_RANGE_VAL 122#define ALS_MAX_RANGE_VAL 223#define POWER_STA_ENABLE 124#define POWER_STA_DISABLE 025 26#define DRIVER_NAME "apds9802als"27 28struct als_data {29 struct mutex mutex;30};31 32static ssize_t als_sensing_range_show(struct device *dev,33 struct device_attribute *attr, char *buf)34{35 struct i2c_client *client = to_i2c_client(dev);36 int val;37 38 val = i2c_smbus_read_byte_data(client, 0x81);39 if (val < 0)40 return val;41 if (val & 1)42 return sprintf(buf, "4095\n");43 else44 return sprintf(buf, "65535\n");45}46 47static int als_wait_for_data_ready(struct device *dev)48{49 struct i2c_client *client = to_i2c_client(dev);50 int ret;51 int retry = 10;52 53 do {54 msleep(30);55 ret = i2c_smbus_read_byte_data(client, 0x86);56 } while (!(ret & 0x80) && retry--);57 58 if (retry < 0) {59 dev_warn(dev, "timeout waiting for data ready\n");60 return -ETIMEDOUT;61 }62 63 return 0;64}65 66static ssize_t als_lux0_input_data_show(struct device *dev,67 struct device_attribute *attr, char *buf)68{69 struct i2c_client *client = to_i2c_client(dev);70 struct als_data *data = i2c_get_clientdata(client);71 int ret_val;72 int temp;73 74 /* Protect against parallel reads */75 pm_runtime_get_sync(dev);76 mutex_lock(&data->mutex);77 78 /* clear EOC interrupt status */79 i2c_smbus_write_byte(client, 0x40);80 /* start measurement */81 temp = i2c_smbus_read_byte_data(client, 0x81);82 i2c_smbus_write_byte_data(client, 0x81, temp | 0x08);83 84 ret_val = als_wait_for_data_ready(dev);85 if (ret_val < 0)86 goto failed;87 88 temp = i2c_smbus_read_byte_data(client, 0x8C); /* LSB data */89 if (temp < 0) {90 ret_val = temp;91 goto failed;92 }93 ret_val = i2c_smbus_read_byte_data(client, 0x8D); /* MSB data */94 if (ret_val < 0)95 goto failed;96 97 mutex_unlock(&data->mutex);98 pm_runtime_put_sync(dev);99 100 temp = (ret_val << 8) | temp;101 return sprintf(buf, "%d\n", temp);102failed:103 mutex_unlock(&data->mutex);104 pm_runtime_put_sync(dev);105 return ret_val;106}107 108static ssize_t als_sensing_range_store(struct device *dev,109 struct device_attribute *attr, const char *buf, size_t count)110{111 struct i2c_client *client = to_i2c_client(dev);112 struct als_data *data = i2c_get_clientdata(client);113 int ret_val;114 unsigned long val;115 116 ret_val = kstrtoul(buf, 10, &val);117 if (ret_val)118 return ret_val;119 120 if (val < 4096)121 val = 1;122 else if (val < 65536)123 val = 2;124 else125 return -ERANGE;126 127 pm_runtime_get_sync(dev);128 129 /* Make sure nobody else reads/modifies/writes 0x81 while we130 are active */131 mutex_lock(&data->mutex);132 133 ret_val = i2c_smbus_read_byte_data(client, 0x81);134 if (ret_val < 0)135 goto fail;136 137 /* Reset the bits before setting them */138 ret_val = ret_val & 0xFA;139 140 if (val == 1) /* Setting detection range up to 4k LUX */141 ret_val = (ret_val | 0x01);142 else /* Setting detection range up to 64k LUX*/143 ret_val = (ret_val | 0x00);144 145 ret_val = i2c_smbus_write_byte_data(client, 0x81, ret_val);146 147 if (ret_val >= 0) {148 /* All OK */149 mutex_unlock(&data->mutex);150 pm_runtime_put_sync(dev);151 return count;152 }153fail:154 mutex_unlock(&data->mutex);155 pm_runtime_put_sync(dev);156 return ret_val;157}158 159static int als_set_power_state(struct i2c_client *client, bool on_off)160{161 int ret_val;162 struct als_data *data = i2c_get_clientdata(client);163 164 mutex_lock(&data->mutex);165 ret_val = i2c_smbus_read_byte_data(client, 0x80);166 if (ret_val < 0)167 goto fail;168 if (on_off)169 ret_val = ret_val | 0x01;170 else171 ret_val = ret_val & 0xFE;172 ret_val = i2c_smbus_write_byte_data(client, 0x80, ret_val);173fail:174 mutex_unlock(&data->mutex);175 return ret_val;176}177 178static DEVICE_ATTR(lux0_sensor_range, S_IRUGO | S_IWUSR,179 als_sensing_range_show, als_sensing_range_store);180static DEVICE_ATTR(lux0_input, S_IRUGO, als_lux0_input_data_show, NULL);181 182static struct attribute *mid_att_als[] = {183 &dev_attr_lux0_sensor_range.attr,184 &dev_attr_lux0_input.attr,185 NULL186};187 188static const struct attribute_group m_als_gr = {189 .name = "apds9802als",190 .attrs = mid_att_als191};192 193static int als_set_default_config(struct i2c_client *client)194{195 int ret_val;196 /* Write the command and then switch on */197 ret_val = i2c_smbus_write_byte_data(client, 0x80, 0x01);198 if (ret_val < 0) {199 dev_err(&client->dev, "failed default switch on write\n");200 return ret_val;201 }202 /* detection range: 1~64K Lux, maunal measurement */203 ret_val = i2c_smbus_write_byte_data(client, 0x81, 0x08);204 if (ret_val < 0)205 dev_err(&client->dev, "failed default LUX on write\n");206 207 /* We always get 0 for the 1st measurement after system power on,208 * so make sure it is finished before user asks for data.209 */210 als_wait_for_data_ready(&client->dev);211 212 return ret_val;213}214 215static int apds9802als_probe(struct i2c_client *client)216{217 int res;218 struct als_data *data;219 220 data = kzalloc(sizeof(struct als_data), GFP_KERNEL);221 if (data == NULL) {222 dev_err(&client->dev, "Memory allocation failed\n");223 return -ENOMEM;224 }225 i2c_set_clientdata(client, data);226 res = sysfs_create_group(&client->dev.kobj, &m_als_gr);227 if (res) {228 dev_err(&client->dev, "device create file failed\n");229 goto als_error1;230 }231 dev_info(&client->dev, "ALS chip found\n");232 als_set_default_config(client);233 mutex_init(&data->mutex);234 235 pm_runtime_set_active(&client->dev);236 pm_runtime_enable(&client->dev);237 238 return res;239als_error1:240 kfree(data);241 return res;242}243 244static void apds9802als_remove(struct i2c_client *client)245{246 struct als_data *data = i2c_get_clientdata(client);247 248 pm_runtime_get_sync(&client->dev);249 250 als_set_power_state(client, false);251 sysfs_remove_group(&client->dev.kobj, &m_als_gr);252 253 pm_runtime_disable(&client->dev);254 pm_runtime_set_suspended(&client->dev);255 pm_runtime_put_noidle(&client->dev);256 257 kfree(data);258}259 260#ifdef CONFIG_PM261 262static int apds9802als_suspend(struct device *dev)263{264 struct i2c_client *client = to_i2c_client(dev);265 266 als_set_power_state(client, false);267 return 0;268}269 270static int apds9802als_resume(struct device *dev)271{272 struct i2c_client *client = to_i2c_client(dev);273 274 als_set_power_state(client, true);275 return 0;276}277 278static UNIVERSAL_DEV_PM_OPS(apds9802als_pm_ops, apds9802als_suspend,279 apds9802als_resume, NULL);280 281#define APDS9802ALS_PM_OPS (&apds9802als_pm_ops)282 283#else /* CONFIG_PM */284#define APDS9802ALS_PM_OPS NULL285#endif /* CONFIG_PM */286 287static const struct i2c_device_id apds9802als_id[] = {288 { DRIVER_NAME },289 { }290};291 292MODULE_DEVICE_TABLE(i2c, apds9802als_id);293 294static struct i2c_driver apds9802als_driver = {295 .driver = {296 .name = DRIVER_NAME,297 .pm = APDS9802ALS_PM_OPS,298 },299 .probe = apds9802als_probe,300 .remove = apds9802als_remove,301 .id_table = apds9802als_id,302};303 304module_i2c_driver(apds9802als_driver);305 306MODULE_AUTHOR("Anantha Narayanan <Anantha.Narayanan@intel.com");307MODULE_DESCRIPTION("Avago apds9802als ALS Driver");308MODULE_LICENSE("GPL v2");309