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authorDaniel Mack <daniel@caiaq.de>2009-03-31 18:23:53 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-04-01 11:59:18 -0400
commit3cdbbeebb77348176bd6a03fd86e11bc281c529e (patch)
tree079d84c58cdb0e6f4d43eee69d42d26d5a48af35 /drivers/misc/isl29003.c
parent891f7d73ea30f925596b90bcf21020bfc5d90f3f (diff)
drivers/misc/isl29003.c: driver for the ISL29003 ambient light sensor
Add a driver for Intersil's ISL29003 ambient light sensor device plus some documentation. Inspired by tsl2550.c, a driver for a similar device. It is put in drivers/misc for now until the industrial I/O framework gets merged. Signed-off-by: Daniel Mack <daniel@caiaq.de> Acked-by: Jonathan Cameron <jic23@cam.ac.uk> Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/misc/isl29003.c')
-rw-r--r--drivers/misc/isl29003.c470
1 files changed, 470 insertions, 0 deletions
diff --git a/drivers/misc/isl29003.c b/drivers/misc/isl29003.c
new file mode 100644
index 000000000000..2e2a5923d4c2
--- /dev/null
+++ b/drivers/misc/isl29003.c
@@ -0,0 +1,470 @@
1/*
2 * isl29003.c - Linux kernel module for
3 * Intersil ISL29003 ambient light sensor
4 *
5 * See file:Documentation/misc-devices/isl29003
6 *
7 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
8 *
9 * Based on code written by
10 * Rodolfo Giometti <giometti@linux.it>
11 * Eurotech S.p.A. <info@eurotech.it>
12 *
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.
17 *
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.
22 *
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.
26 */
27
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>
34
35#define ISL29003_DRV_NAME "isl29003"
36#define DRIVER_VERSION "1.0"
37
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)
46
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)
53
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
60
61#define ISL29003_NUM_CACHABLE_REGS 4
62
63struct isl29003_data {
64 struct i2c_client *client;
65 struct mutex lock;
66 u8 reg_cache[ISL29003_NUM_CACHABLE_REGS];
67};
68
69static int gain_range[] = {
70 1000, 4000, 16000, 64000
71};
72
73/*
74 * register access helpers
75 */
76
77static int __isl29003_read_reg(struct i2c_client *client,
78 u32 reg, u8 mask, u8 shift)
79{
80 struct isl29003_data *data = i2c_get_clientdata(client);
81 return (data->reg_cache[reg] & mask) >> shift;
82}
83
84static int __isl29003_write_reg(struct i2c_client *client,
85 u32 reg, u8 mask, u8 shift, u8 val)
86{
87 struct isl29003_data *data = i2c_get_clientdata(client);
88 int ret = 0;
89 u8 tmp;
90
91 if (reg >= ISL29003_NUM_CACHABLE_REGS)
92 return -EINVAL;
93
94 mutex_lock(&data->lock);
95
96 tmp = data->reg_cache[reg];
97 tmp &= ~mask;
98 tmp |= val << shift;
99
100 ret = i2c_smbus_write_byte_data(client, reg, tmp);
101 if (!ret)
102 data->reg_cache[reg] = tmp;
103
104 mutex_unlock(&data->lock);
105 return ret;
106}
107
108/*
109 * internally used functions
110 */
111
112/* range */
113static int isl29003_get_range(struct i2c_client *client)
114{
115 return __isl29003_read_reg(client, ISL29003_REG_CONTROL,
116 ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT);
117}
118
119static int isl29003_set_range(struct i2c_client *client, int range)
120{
121 return __isl29003_write_reg(client, ISL29003_REG_CONTROL,
122 ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT, range);
123}
124
125/* resolution */
126static int isl29003_get_resolution(struct i2c_client *client)
127{
128 return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
129 ISL29003_RES_MASK, ISL29003_RES_SHIFT);
130}
131
132static int isl29003_set_resolution(struct i2c_client *client, int res)
133{
134 return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
135 ISL29003_RES_MASK, ISL29003_RES_SHIFT, res);
136}
137
138/* mode */
139static int isl29003_get_mode(struct i2c_client *client)
140{
141 return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
142 ISL29003_RES_MASK, ISL29003_RES_SHIFT);
143}
144
145static int isl29003_set_mode(struct i2c_client *client, int mode)
146{
147 return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
148 ISL29003_RES_MASK, ISL29003_RES_SHIFT, mode);
149}
150
151/* power_state */
152static int isl29003_set_power_state(struct i2c_client *client, int state)
153{
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);
157}
158
159static int isl29003_get_power_state(struct i2c_client *client)
160{
161 struct isl29003_data *data = i2c_get_clientdata(client);
162 u8 cmdreg = data->reg_cache[ISL29003_REG_COMMAND];
163 return ~cmdreg & ISL29003_ADC_PD;
164}
165
166static int isl29003_get_adc_value(struct i2c_client *client)
167{
168 struct isl29003_data *data = i2c_get_clientdata(client);
169 int lsb, msb, range, bitdepth;
170
171 mutex_lock(&data->lock);
172 lsb = i2c_smbus_read_byte_data(client, ISL29003_REG_LSB_SENSOR);
173
174 if (lsb < 0) {
175 mutex_unlock(&data->lock);
176 return lsb;
177 }
178
179 msb = i2c_smbus_read_byte_data(client, ISL29003_REG_MSB_SENSOR);
180 mutex_unlock(&data->lock);
181
182 if (msb < 0)
183 return msb;
184
185 range = isl29003_get_range(client);
186 bitdepth = (4 - isl29003_get_resolution(client)) * 4;
187 return (((msb << 8) | lsb) * gain_range[range]) >> bitdepth;
188}
189
190/*
191 * sysfs layer
192 */
193
194/* range */
195static ssize_t isl29003_show_range(struct device *dev,
196 struct device_attribute *attr, char *buf)
197{
198 struct i2c_client *client = to_i2c_client(dev);
199 return sprintf(buf, "%i\n", isl29003_get_range(client));
200}
201
202static ssize_t isl29003_store_range(struct device *dev,
203 struct device_attribute *attr,
204 const char *buf, size_t count)
205{
206 struct i2c_client *client = to_i2c_client(dev);
207 unsigned long val;
208 int ret;
209
210 if ((strict_strtoul(buf, 10, &val) < 0) || (val > 3))
211 return -EINVAL;
212
213 ret = isl29003_set_range(client, val);
214 if (ret < 0)
215 return ret;
216
217 return count;
218}
219
220static DEVICE_ATTR(range, S_IWUSR | S_IRUGO,
221 isl29003_show_range, isl29003_store_range);
222
223
224/* resolution */
225static ssize_t isl29003_show_resolution(struct device *dev,
226 struct device_attribute *attr,
227 char *buf)
228{
229 struct i2c_client *client = to_i2c_client(dev);
230 return sprintf(buf, "%d\n", isl29003_get_resolution(client));
231}
232
233static ssize_t isl29003_store_resolution(struct device *dev,
234 struct device_attribute *attr,
235 const char *buf, size_t count)
236{
237 struct i2c_client *client = to_i2c_client(dev);
238 unsigned long val;
239 int ret;
240
241 if ((strict_strtoul(buf, 10, &val) < 0) || (val > 3))
242 return -EINVAL;
243
244 ret = isl29003_set_resolution(client, val);
245 if (ret < 0)
246 return ret;
247
248 return count;
249}
250
251static DEVICE_ATTR(resolution, S_IWUSR | S_IRUGO,
252 isl29003_show_resolution, isl29003_store_resolution);
253
254/* mode */
255static ssize_t isl29003_show_mode(struct device *dev,
256 struct device_attribute *attr, char *buf)
257{
258 struct i2c_client *client = to_i2c_client(dev);
259 return sprintf(buf, "%d\n", isl29003_get_mode(client));
260}
261
262static ssize_t isl29003_store_mode(struct device *dev,
263 struct device_attribute *attr, const char *buf, size_t count)
264{
265 struct i2c_client *client = to_i2c_client(dev);
266 unsigned long val;
267 int ret;
268
269 if ((strict_strtoul(buf, 10, &val) < 0) || (val > 2))
270 return -EINVAL;
271
272 ret = isl29003_set_mode(client, val);
273 if (ret < 0)
274 return ret;
275
276 return count;
277}
278
279static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO,
280 isl29003_show_mode, isl29003_store_mode);
281
282
283/* power state */
284static ssize_t isl29003_show_power_state(struct device *dev,
285 struct device_attribute *attr,
286 char *buf)
287{
288 struct i2c_client *client = to_i2c_client(dev);
289 return sprintf(buf, "%d\n", isl29003_get_power_state(client));
290}
291
292static ssize_t isl29003_store_power_state(struct device *dev,
293 struct device_attribute *attr,
294 const char *buf, size_t count)
295{
296 struct i2c_client *client = to_i2c_client(dev);
297 unsigned long val;
298 int ret;
299
300 if ((strict_strtoul(buf, 10, &val) < 0) || (val > 1))
301 return -EINVAL;
302
303 ret = isl29003_set_power_state(client, val);
304 return ret ? ret : count;
305}
306
307static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
308 isl29003_show_power_state, isl29003_store_power_state);
309
310
311/* lux */
312static ssize_t isl29003_show_lux(struct device *dev,
313 struct device_attribute *attr, char *buf)
314{
315 struct i2c_client *client = to_i2c_client(dev);
316
317 /* No LUX data if not operational */
318 if (!isl29003_get_power_state(client))
319 return -EBUSY;
320
321 return sprintf(buf, "%d\n", isl29003_get_adc_value(client));
322}
323
324static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL);
325
326static struct attribute *isl29003_attributes[] = {
327 &dev_attr_range.attr,
328 &dev_attr_resolution.attr,
329 &dev_attr_mode.attr,
330 &dev_attr_power_state.attr,
331 &dev_attr_lux.attr,
332 NULL
333};
334
335static const struct attribute_group isl29003_attr_group = {
336 .attrs = isl29003_attributes,
337};
338
339static int isl29003_init_client(struct i2c_client *client)
340{
341 struct isl29003_data *data = i2c_get_clientdata(client);
342 int i;
343
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);
348 if (v < 0)
349 return -ENODEV;
350
351 data->reg_cache[i] = v;
352 }
353
354 /* set defaults */
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);
359
360 return 0;
361}
362
363/*
364 * I2C layer
365 */
366
367static int __devinit isl29003_probe(struct i2c_client *client,
368 const struct i2c_device_id *id)
369{
370 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
371 struct isl29003_data *data;
372 int err = 0;
373
374 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
375 return -EIO;
376
377 data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL);
378 if (!data)
379 return -ENOMEM;
380
381 data->client = client;
382 i2c_set_clientdata(client, data);
383 mutex_init(&data->lock);
384
385 /* initialize the ISL29003 chip */
386 err = isl29003_init_client(client);
387 if (err)
388 goto exit_kfree;
389
390 /* register sysfs hooks */
391 err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group);
392 if (err)
393 goto exit_kfree;
394
395 dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION);
396 return 0;
397
398exit_kfree:
399 kfree(data);
400 return err;
401}
402
403static int __devexit isl29003_remove(struct i2c_client *client)
404{
405 sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group);
406 isl29003_set_power_state(client, 0);
407 kfree(i2c_get_clientdata(client));
408 return 0;
409}
410
411#ifdef CONFIG_PM
412static int isl29003_suspend(struct i2c_client *client, pm_message_t mesg)
413{
414 return isl29003_set_power_state(client, 0);
415}
416
417static int isl29003_resume(struct i2c_client *client)
418{
419 int i;
420 struct isl29003_data *data = i2c_get_clientdata(client);
421
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]))
425 return -EIO;
426
427 return 0;
428}
429
430#else
431#define isl29003_suspend NULL
432#define isl29003_resume NULL
433#endif /* CONFIG_PM */
434
435static const struct i2c_device_id isl29003_id[] = {
436 { "isl29003", 0 },
437 {}
438};
439MODULE_DEVICE_TABLE(i2c, isl29003_id);
440
441static struct i2c_driver isl29003_driver = {
442 .driver = {
443 .name = ISL29003_DRV_NAME,
444 .owner = THIS_MODULE,
445 },
446 .suspend = isl29003_suspend,
447 .resume = isl29003_resume,
448 .probe = isl29003_probe,
449 .remove = __devexit_p(isl29003_remove),
450 .id_table = isl29003_id,
451};
452
453static int __init isl29003_init(void)
454{
455 return i2c_add_driver(&isl29003_driver);
456}
457
458static void __exit isl29003_exit(void)
459{
460 i2c_del_driver(&isl29003_driver);
461}
462
463MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
464MODULE_DESCRIPTION("ISL29003 ambient light sensor driver");
465MODULE_LICENSE("GPL v2");
466MODULE_VERSION(DRIVER_VERSION);
467
468module_init(isl29003_init);
469module_exit(isl29003_exit);
470