2 * isl29003.c - Linux kernel module for
3 * Intersil ISL29003 ambient light sensor
5 * See file:Documentation/misc-devices/isl29003
7 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
9 * Based on code written by
10 * Rodolfo Giometti <giometti@linux.it>
11 * Eurotech S.p.A. <info@eurotech.it>
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/slab.h>
31 #include <linux/i2c.h>
32 #include <linux/mutex.h>
33 #include <linux/delay.h>
35 #define ISL29003_DRV_NAME "isl29003"
36 #define DRIVER_VERSION "1.0"
38 #define ISL29003_REG_COMMAND 0x00
39 #define ISL29003_ADC_ENABLED (1 << 7)
40 #define ISL29003_ADC_PD (1 << 6)
41 #define ISL29003_TIMING_INT (1 << 5)
42 #define ISL29003_MODE_SHIFT (2)
43 #define ISL29003_MODE_MASK (0x3 << ISL29003_MODE_SHIFT)
44 #define ISL29003_RES_SHIFT (0)
45 #define ISL29003_RES_MASK (0x3 << ISL29003_RES_SHIFT)
47 #define ISL29003_REG_CONTROL 0x01
48 #define ISL29003_INT_FLG (1 << 5)
49 #define ISL29003_RANGE_SHIFT (2)
50 #define ISL29003_RANGE_MASK (0x3 << ISL29003_RANGE_SHIFT)
51 #define ISL29003_INT_PERSISTS_SHIFT (0)
52 #define ISL29003_INT_PERSISTS_MASK (0xf << ISL29003_INT_PERSISTS_SHIFT)
54 #define ISL29003_REG_IRQ_THRESH_HI 0x02
55 #define ISL29003_REG_IRQ_THRESH_LO 0x03
56 #define ISL29003_REG_LSB_SENSOR 0x04
57 #define ISL29003_REG_MSB_SENSOR 0x05
58 #define ISL29003_REG_LSB_TIMER 0x06
59 #define ISL29003_REG_MSB_TIMER 0x07
61 #define ISL29003_NUM_CACHABLE_REGS 4
63 struct isl29003_data {
64 struct i2c_client *client;
66 u8 reg_cache[ISL29003_NUM_CACHABLE_REGS];
69 static int gain_range[] = {
70 1000, 4000, 16000, 64000
74 * register access helpers
77 static int __isl29003_read_reg(struct i2c_client *client,
78 u32 reg, u8 mask, u8 shift)
80 struct isl29003_data *data = i2c_get_clientdata(client);
81 return (data->reg_cache[reg] & mask) >> shift;
84 static int __isl29003_write_reg(struct i2c_client *client,
85 u32 reg, u8 mask, u8 shift, u8 val)
87 struct isl29003_data *data = i2c_get_clientdata(client);
91 if (reg >= ISL29003_NUM_CACHABLE_REGS)
94 mutex_lock(&data->lock);
96 tmp = data->reg_cache[reg];
100 ret = i2c_smbus_write_byte_data(client, reg, tmp);
102 data->reg_cache[reg] = tmp;
104 mutex_unlock(&data->lock);
109 * internally used functions
113 static int isl29003_get_range(struct i2c_client *client)
115 return __isl29003_read_reg(client, ISL29003_REG_CONTROL,
116 ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT);
119 static int isl29003_set_range(struct i2c_client *client, int range)
121 return __isl29003_write_reg(client, ISL29003_REG_CONTROL,
122 ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT, range);
126 static int isl29003_get_resolution(struct i2c_client *client)
128 return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
129 ISL29003_RES_MASK, ISL29003_RES_SHIFT);
132 static int isl29003_set_resolution(struct i2c_client *client, int res)
134 return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
135 ISL29003_RES_MASK, ISL29003_RES_SHIFT, res);
139 static int isl29003_get_mode(struct i2c_client *client)
141 return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
142 ISL29003_RES_MASK, ISL29003_RES_SHIFT);
145 static int isl29003_set_mode(struct i2c_client *client, int mode)
147 return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
148 ISL29003_RES_MASK, ISL29003_RES_SHIFT, mode);
152 static int isl29003_set_power_state(struct i2c_client *client, int state)
154 return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
155 ISL29003_ADC_ENABLED | ISL29003_ADC_PD, 0,
156 state ? ISL29003_ADC_ENABLED : ISL29003_ADC_PD);
159 static int isl29003_get_power_state(struct i2c_client *client)
161 struct isl29003_data *data = i2c_get_clientdata(client);
162 u8 cmdreg = data->reg_cache[ISL29003_REG_COMMAND];
163 return ~cmdreg & ISL29003_ADC_PD;
166 static int isl29003_get_adc_value(struct i2c_client *client)
168 struct isl29003_data *data = i2c_get_clientdata(client);
169 int lsb, msb, range, bitdepth;
171 mutex_lock(&data->lock);
172 lsb = i2c_smbus_read_byte_data(client, ISL29003_REG_LSB_SENSOR);
175 mutex_unlock(&data->lock);
179 msb = i2c_smbus_read_byte_data(client, ISL29003_REG_MSB_SENSOR);
180 mutex_unlock(&data->lock);
185 range = isl29003_get_range(client);
186 bitdepth = (4 - isl29003_get_resolution(client)) * 4;
187 return (((msb << 8) | lsb) * gain_range[range]) >> bitdepth;
195 static ssize_t isl29003_show_range(struct device *dev,
196 struct device_attribute *attr, char *buf)
198 struct i2c_client *client = to_i2c_client(dev);
199 return sprintf(buf, "%i\n", isl29003_get_range(client));
202 static ssize_t isl29003_store_range(struct device *dev,
203 struct device_attribute *attr,
204 const char *buf, size_t count)
206 struct i2c_client *client = to_i2c_client(dev);
210 if ((strict_strtoul(buf, 10, &val) < 0) || (val > 3))
213 ret = isl29003_set_range(client, val);
220 static DEVICE_ATTR(range, S_IWUSR | S_IRUGO,
221 isl29003_show_range, isl29003_store_range);
225 static ssize_t isl29003_show_resolution(struct device *dev,
226 struct device_attribute *attr,
229 struct i2c_client *client = to_i2c_client(dev);
230 return sprintf(buf, "%d\n", isl29003_get_resolution(client));
233 static ssize_t isl29003_store_resolution(struct device *dev,
234 struct device_attribute *attr,
235 const char *buf, size_t count)
237 struct i2c_client *client = to_i2c_client(dev);
241 if ((strict_strtoul(buf, 10, &val) < 0) || (val > 3))
244 ret = isl29003_set_resolution(client, val);
251 static DEVICE_ATTR(resolution, S_IWUSR | S_IRUGO,
252 isl29003_show_resolution, isl29003_store_resolution);
255 static ssize_t isl29003_show_mode(struct device *dev,
256 struct device_attribute *attr, char *buf)
258 struct i2c_client *client = to_i2c_client(dev);
259 return sprintf(buf, "%d\n", isl29003_get_mode(client));
262 static ssize_t isl29003_store_mode(struct device *dev,
263 struct device_attribute *attr, const char *buf, size_t count)
265 struct i2c_client *client = to_i2c_client(dev);
269 if ((strict_strtoul(buf, 10, &val) < 0) || (val > 2))
272 ret = isl29003_set_mode(client, val);
279 static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO,
280 isl29003_show_mode, isl29003_store_mode);
284 static ssize_t isl29003_show_power_state(struct device *dev,
285 struct device_attribute *attr,
288 struct i2c_client *client = to_i2c_client(dev);
289 return sprintf(buf, "%d\n", isl29003_get_power_state(client));
292 static ssize_t isl29003_store_power_state(struct device *dev,
293 struct device_attribute *attr,
294 const char *buf, size_t count)
296 struct i2c_client *client = to_i2c_client(dev);
300 if ((strict_strtoul(buf, 10, &val) < 0) || (val > 1))
303 ret = isl29003_set_power_state(client, val);
304 return ret ? ret : count;
307 static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
308 isl29003_show_power_state, isl29003_store_power_state);
312 static ssize_t isl29003_show_lux(struct device *dev,
313 struct device_attribute *attr, char *buf)
315 struct i2c_client *client = to_i2c_client(dev);
317 /* No LUX data if not operational */
318 if (!isl29003_get_power_state(client))
321 return sprintf(buf, "%d\n", isl29003_get_adc_value(client));
324 static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL);
326 static struct attribute *isl29003_attributes[] = {
327 &dev_attr_range.attr,
328 &dev_attr_resolution.attr,
330 &dev_attr_power_state.attr,
335 static const struct attribute_group isl29003_attr_group = {
336 .attrs = isl29003_attributes,
339 static int isl29003_init_client(struct i2c_client *client)
341 struct isl29003_data *data = i2c_get_clientdata(client);
344 /* read all the registers once to fill the cache.
345 * if one of the reads fails, we consider the init failed */
346 for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) {
347 int v = i2c_smbus_read_byte_data(client, i);
351 data->reg_cache[i] = v;
355 isl29003_set_range(client, 0);
356 isl29003_set_resolution(client, 0);
357 isl29003_set_mode(client, 0);
358 isl29003_set_power_state(client, 0);
367 static int __devinit isl29003_probe(struct i2c_client *client,
368 const struct i2c_device_id *id)
370 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
371 struct isl29003_data *data;
374 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
377 data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL);
381 data->client = client;
382 i2c_set_clientdata(client, data);
383 mutex_init(&data->lock);
385 /* initialize the ISL29003 chip */
386 err = isl29003_init_client(client);
390 /* register sysfs hooks */
391 err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group);
395 dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION);
403 static int __devexit isl29003_remove(struct i2c_client *client)
405 sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group);
406 isl29003_set_power_state(client, 0);
407 kfree(i2c_get_clientdata(client));
412 static int isl29003_suspend(struct i2c_client *client, pm_message_t mesg)
414 return isl29003_set_power_state(client, 0);
417 static int isl29003_resume(struct i2c_client *client)
420 struct isl29003_data *data = i2c_get_clientdata(client);
422 /* restore registers from cache */
423 for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++)
424 if (!i2c_smbus_write_byte_data(client, i, data->reg_cache[i]))
431 #define isl29003_suspend NULL
432 #define isl29003_resume NULL
433 #endif /* CONFIG_PM */
435 static const struct i2c_device_id isl29003_id[] = {
439 MODULE_DEVICE_TABLE(i2c, isl29003_id);
441 static struct i2c_driver isl29003_driver = {
443 .name = ISL29003_DRV_NAME,
444 .owner = THIS_MODULE,
446 .suspend = isl29003_suspend,
447 .resume = isl29003_resume,
448 .probe = isl29003_probe,
449 .remove = __devexit_p(isl29003_remove),
450 .id_table = isl29003_id,
453 static int __init isl29003_init(void)
455 return i2c_add_driver(&isl29003_driver);
458 static void __exit isl29003_exit(void)
460 i2c_del_driver(&isl29003_driver);
463 MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
464 MODULE_DESCRIPTION("ISL29003 ambient light sensor driver");
465 MODULE_LICENSE("GPL v2");
466 MODULE_VERSION(DRIVER_VERSION);
468 module_init(isl29003_init);
469 module_exit(isl29003_exit);