anantha | 22d96aa | 2010-10-26 14:22:41 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * apds9802als.c - apds9802 ALS Driver |
| 3 | * |
| 4 | * Copyright (C) 2009 Intel Corp |
| 5 | * |
| 6 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License as published by |
| 10 | * the Free Software Foundation; version 2 of the License. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, but |
| 13 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License along |
| 18 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 19 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. |
| 20 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 21 | * |
| 22 | */ |
| 23 | |
| 24 | #include <linux/module.h> |
| 25 | #include <linux/init.h> |
| 26 | #include <linux/slab.h> |
| 27 | #include <linux/i2c.h> |
| 28 | #include <linux/err.h> |
| 29 | #include <linux/delay.h> |
| 30 | #include <linux/mutex.h> |
| 31 | #include <linux/sysfs.h> |
| 32 | #include <linux/hwmon-sysfs.h> |
| 33 | |
| 34 | #define ALS_MIN_RANGE_VAL 1 |
| 35 | #define ALS_MAX_RANGE_VAL 2 |
| 36 | #define POWER_STA_ENABLE 1 |
| 37 | #define POWER_STA_DISABLE 0 |
| 38 | #define APDS9802ALS_I2C_ADDR 0x29 |
| 39 | |
| 40 | #define DRIVER_NAME "apds9802als" |
| 41 | |
| 42 | struct als_data { |
| 43 | struct device *hwmon_dev; |
| 44 | bool needresume; |
| 45 | struct mutex mutex; |
| 46 | }; |
| 47 | |
| 48 | static ssize_t als_sensing_range_show(struct device *dev, |
| 49 | struct device_attribute *attr, char *buf) |
| 50 | { |
| 51 | struct i2c_client *client = to_i2c_client(dev); |
| 52 | int val; |
| 53 | |
| 54 | val = i2c_smbus_read_byte_data(client, 0x81); |
| 55 | if (val < 0) |
| 56 | return val; |
| 57 | if (val & 1) |
| 58 | return sprintf(buf, "4095\n"); |
| 59 | else |
| 60 | return sprintf(buf, "65535\n"); |
| 61 | } |
| 62 | |
| 63 | static ssize_t als_lux0_input_data_show(struct device *dev, |
| 64 | struct device_attribute *attr, char *buf) |
| 65 | { |
| 66 | struct i2c_client *client = to_i2c_client(dev); |
| 67 | struct als_data *data = i2c_get_clientdata(client); |
| 68 | unsigned int ret_val; |
| 69 | int temp; |
| 70 | |
| 71 | /* Protect against parallel reads */ |
| 72 | mutex_lock(&data->mutex); |
| 73 | temp = i2c_smbus_read_byte_data(client, 0x8C);/*LSB data*/ |
| 74 | if (temp < 0) { |
| 75 | ret_val = temp; |
| 76 | goto failed; |
| 77 | } |
| 78 | ret_val = i2c_smbus_read_byte_data(client, 0x8D);/*MSB data*/ |
| 79 | if (ret_val < 0) |
| 80 | goto failed; |
| 81 | mutex_unlock(&data->mutex); |
| 82 | ret_val = (ret_val << 8) | temp; |
| 83 | return sprintf(buf, "%d\n", ret_val); |
| 84 | failed: |
| 85 | mutex_unlock(&data->mutex); |
| 86 | return ret_val; |
| 87 | } |
| 88 | |
| 89 | static ssize_t als_sensing_range_store(struct device *dev, |
| 90 | struct device_attribute *attr, const char *buf, size_t count) |
| 91 | { |
| 92 | struct i2c_client *client = to_i2c_client(dev); |
| 93 | struct als_data *data = i2c_get_clientdata(client); |
| 94 | unsigned int ret_val; |
| 95 | unsigned long val; |
| 96 | |
| 97 | if (strict_strtoul(buf, 10, &val)) |
| 98 | return -EINVAL; |
| 99 | |
| 100 | if (val < 4096) |
| 101 | val = 1; |
| 102 | else if (val < 65536) |
| 103 | val = 2; |
| 104 | else |
| 105 | return -ERANGE; |
| 106 | |
| 107 | /* Make sure nobody else reads/modifies/writes 0x81 while we |
| 108 | are active */ |
| 109 | |
| 110 | mutex_lock(&data->mutex); |
| 111 | |
| 112 | ret_val = i2c_smbus_read_byte_data(client, 0x81); |
| 113 | if (ret_val < 0) |
| 114 | goto fail; |
| 115 | |
| 116 | /* Reset the bits before setting them */ |
| 117 | ret_val = ret_val & 0xFA; |
| 118 | |
| 119 | if (val == 1) /* Setting the continous measurement up to 4k LUX */ |
| 120 | ret_val = (ret_val | 0x05); |
| 121 | else /* Setting the continous measurement up to 64k LUX*/ |
| 122 | ret_val = (ret_val | 0x04); |
| 123 | |
| 124 | ret_val = i2c_smbus_write_byte_data(client, 0x81, ret_val); |
| 125 | if (ret_val >= 0) { |
| 126 | /* All OK */ |
| 127 | mutex_unlock(&data->mutex); |
| 128 | return count; |
| 129 | } |
| 130 | fail: |
| 131 | mutex_unlock(&data->mutex); |
| 132 | return ret_val; |
| 133 | } |
| 134 | |
| 135 | static ssize_t als_power_status_show(struct device *dev, |
| 136 | struct device_attribute *attr, char *buf) |
| 137 | { |
| 138 | struct i2c_client *client = to_i2c_client(dev); |
| 139 | int ret_val; |
| 140 | ret_val = i2c_smbus_read_byte_data(client, 0x80); |
| 141 | if (ret_val < 0) |
| 142 | return ret_val; |
| 143 | ret_val = ret_val & 0x01; |
| 144 | return sprintf(buf, "%d\n", ret_val); |
| 145 | } |
| 146 | |
| 147 | static int als_set_power_state(struct i2c_client *client, bool on_off) |
| 148 | { |
| 149 | int ret_val; |
| 150 | struct als_data *data = i2c_get_clientdata(client); |
| 151 | |
| 152 | mutex_lock(&data->mutex); |
| 153 | ret_val = i2c_smbus_read_byte_data(client, 0x80); |
| 154 | if (ret_val < 0) |
| 155 | goto fail; |
| 156 | if (on_off) |
| 157 | ret_val = ret_val | 0x01; |
| 158 | else |
| 159 | ret_val = ret_val & 0xFE; |
| 160 | ret_val = i2c_smbus_write_byte_data(client, 0x80, ret_val); |
| 161 | fail: |
| 162 | mutex_unlock(&data->mutex); |
| 163 | return ret_val; |
| 164 | } |
| 165 | |
| 166 | static ssize_t als_power_status_store(struct device *dev, |
| 167 | struct device_attribute *attr, const char *buf, size_t count) |
| 168 | { |
| 169 | struct i2c_client *client = to_i2c_client(dev); |
| 170 | struct als_data *data = i2c_get_clientdata(client); |
| 171 | unsigned long val; |
| 172 | int ret_val; |
| 173 | |
| 174 | if (strict_strtoul(buf, 10, &val)) |
| 175 | return -EINVAL; |
| 176 | if (val == POWER_STA_ENABLE) { |
| 177 | ret_val = als_set_power_state(client, true); |
| 178 | data->needresume = true; |
| 179 | } else if (val == POWER_STA_DISABLE) { |
| 180 | ret_val = als_set_power_state(client, false); |
| 181 | data->needresume = false; |
| 182 | } else |
| 183 | return -EINVAL; |
| 184 | if (ret_val < 0) |
| 185 | return ret_val; |
| 186 | return count; |
| 187 | } |
| 188 | |
| 189 | static DEVICE_ATTR(lux0_sensor_range, S_IRUGO | S_IWUSR, |
| 190 | als_sensing_range_show, als_sensing_range_store); |
| 191 | static DEVICE_ATTR(lux0_input, S_IRUGO, als_lux0_input_data_show, NULL); |
| 192 | static DEVICE_ATTR(power_state, S_IRUGO | S_IWUSR, |
| 193 | als_power_status_show, als_power_status_store); |
| 194 | |
| 195 | static struct attribute *mid_att_als[] = { |
| 196 | &dev_attr_lux0_sensor_range.attr, |
| 197 | &dev_attr_lux0_input.attr, |
| 198 | &dev_attr_power_state.attr, |
| 199 | NULL |
| 200 | }; |
| 201 | |
| 202 | static struct attribute_group m_als_gr = { |
| 203 | .name = "apds9802als", |
| 204 | .attrs = mid_att_als |
| 205 | }; |
| 206 | |
| 207 | static int als_set_default_config(struct i2c_client *client) |
| 208 | { |
| 209 | int ret_val; |
| 210 | /* Write the command and then switch on */ |
| 211 | ret_val = i2c_smbus_write_byte_data(client, 0x80, 0x01); |
| 212 | if (ret_val < 0) { |
| 213 | dev_err(&client->dev, "failed default switch on write\n"); |
| 214 | return ret_val; |
| 215 | } |
| 216 | /* Continous from 1Lux to 64k Lux */ |
| 217 | ret_val = i2c_smbus_write_byte_data(client, 0x81, 0x04); |
| 218 | if (ret_val < 0) |
| 219 | dev_err(&client->dev, "failed default LUX on write\n"); |
| 220 | return ret_val; |
| 221 | } |
| 222 | |
| 223 | static int apds9802als_probe(struct i2c_client *client, |
| 224 | const struct i2c_device_id *id) |
| 225 | { |
| 226 | int res; |
| 227 | struct als_data *data; |
| 228 | |
| 229 | data = kzalloc(sizeof(struct als_data), GFP_KERNEL); |
| 230 | if (data == NULL) { |
| 231 | dev_err(&client->dev, "Memory allocation failed\n"); |
| 232 | return -ENOMEM; |
| 233 | } |
| 234 | i2c_set_clientdata(client, data); |
| 235 | res = sysfs_create_group(&client->dev.kobj, &m_als_gr); |
| 236 | if (res) { |
| 237 | dev_err(&client->dev, "device create file failed\n"); |
| 238 | goto als_error1; |
| 239 | } |
| 240 | dev_info(&client->dev, |
| 241 | "%s apds9802als: ALS chip found\n", client->name); |
| 242 | als_set_default_config(client); |
| 243 | data->needresume = true; |
| 244 | mutex_init(&data->mutex); |
| 245 | return res; |
| 246 | als_error1: |
| 247 | i2c_set_clientdata(client, NULL); |
| 248 | kfree(data); |
| 249 | return res; |
| 250 | } |
| 251 | |
| 252 | static int apds9802als_remove(struct i2c_client *client) |
| 253 | { |
| 254 | struct als_data *data = i2c_get_clientdata(client); |
| 255 | sysfs_remove_group(&client->dev.kobj, &m_als_gr); |
| 256 | kfree(data); |
| 257 | return 0; |
| 258 | } |
| 259 | |
| 260 | static int apds9802als_suspend(struct i2c_client *client, pm_message_t mesg) |
| 261 | { |
| 262 | als_set_power_state(client, false); |
| 263 | return 0; |
| 264 | } |
| 265 | |
| 266 | static int apds9802als_resume(struct i2c_client *client) |
| 267 | { |
| 268 | struct als_data *data = i2c_get_clientdata(client); |
| 269 | |
| 270 | if (data->needresume == true) |
| 271 | als_set_power_state(client, true); |
| 272 | return 0; |
| 273 | } |
| 274 | |
| 275 | static struct i2c_device_id apds9802als_id[] = { |
| 276 | { DRIVER_NAME, 0 }, |
| 277 | { } |
| 278 | }; |
| 279 | |
| 280 | MODULE_DEVICE_TABLE(i2c, apds9802als_id); |
| 281 | |
| 282 | static struct i2c_driver apds9802als_driver = { |
| 283 | .driver = { |
| 284 | .name = DRIVER_NAME, |
| 285 | .owner = THIS_MODULE, |
| 286 | }, |
| 287 | .probe = apds9802als_probe, |
| 288 | .remove = apds9802als_remove, |
| 289 | .suspend = apds9802als_suspend, |
| 290 | .resume = apds9802als_resume, |
| 291 | .id_table = apds9802als_id, |
| 292 | }; |
| 293 | |
| 294 | static int __init sensor_apds9802als_init(void) |
| 295 | { |
| 296 | return i2c_add_driver(&apds9802als_driver); |
| 297 | } |
| 298 | |
| 299 | static void __exit sensor_apds9802als_exit(void) |
| 300 | { |
| 301 | i2c_del_driver(&apds9802als_driver); |
| 302 | } |
| 303 | module_init(sensor_apds9802als_init); |
| 304 | module_exit(sensor_apds9802als_exit); |
| 305 | |
| 306 | MODULE_AUTHOR("Anantha Narayanan <Anantha.Narayanan@intel.com"); |
| 307 | MODULE_DESCRIPTION("Avago apds9802als ALS Driver"); |
| 308 | MODULE_LICENSE("GPL v2"); |