1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * isl29003.c - Linux kernel module for
4 * Intersil ISL29003 ambient light sensor
5 *
6 * See file:Documentation/misc-devices/isl29003.rst
7 *
8 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
9 *
10 * Based on code written by
11 * Rodolfo Giometti <giometti@linux.it>
12 * Eurotech S.p.A. <info@eurotech.it>
13 */
14
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 #include <linux/i2c.h>
18 #include <linux/mutex.h>
19 #include <linux/delay.h>
20
21 #define ISL29003_DRV_NAME "isl29003"
22 #define DRIVER_VERSION "1.0"
23
24 #define ISL29003_REG_COMMAND 0x00
25 #define ISL29003_ADC_ENABLED (1 << 7)
26 #define ISL29003_ADC_PD (1 << 6)
27 #define ISL29003_TIMING_INT (1 << 5)
28 #define ISL29003_MODE_SHIFT (2)
29 #define ISL29003_MODE_MASK (0x3 << ISL29003_MODE_SHIFT)
30 #define ISL29003_RES_SHIFT (0)
31 #define ISL29003_RES_MASK (0x3 << ISL29003_RES_SHIFT)
32
33 #define ISL29003_REG_CONTROL 0x01
34 #define ISL29003_INT_FLG (1 << 5)
35 #define ISL29003_RANGE_SHIFT (2)
36 #define ISL29003_RANGE_MASK (0x3 << ISL29003_RANGE_SHIFT)
37 #define ISL29003_INT_PERSISTS_SHIFT (0)
38 #define ISL29003_INT_PERSISTS_MASK (0xf << ISL29003_INT_PERSISTS_SHIFT)
39
40 #define ISL29003_REG_IRQ_THRESH_HI 0x02
41 #define ISL29003_REG_IRQ_THRESH_LO 0x03
42 #define ISL29003_REG_LSB_SENSOR 0x04
43 #define ISL29003_REG_MSB_SENSOR 0x05
44 #define ISL29003_REG_LSB_TIMER 0x06
45 #define ISL29003_REG_MSB_TIMER 0x07
46
47 #define ISL29003_NUM_CACHABLE_REGS 4
48
49 struct isl29003_data {
50 struct i2c_client *client;
51 struct mutex lock;
52 u8 reg_cache[ISL29003_NUM_CACHABLE_REGS];
53 u8 power_state_before_suspend;
54 };
55
56 static int gain_range[] = {
57 1000, 4000, 16000, 64000
58 };
59
60 /*
61 * register access helpers
62 */
63
__isl29003_read_reg(struct i2c_client * client,u32 reg,u8 mask,u8 shift)64 static int __isl29003_read_reg(struct i2c_client *client,
65 u32 reg, u8 mask, u8 shift)
66 {
67 struct isl29003_data *data = i2c_get_clientdata(client);
68
69 return (data->reg_cache[reg] & mask) >> shift;
70 }
71
__isl29003_write_reg(struct i2c_client * client,u32 reg,u8 mask,u8 shift,u8 val)72 static int __isl29003_write_reg(struct i2c_client *client,
73 u32 reg, u8 mask, u8 shift, u8 val)
74 {
75 struct isl29003_data *data = i2c_get_clientdata(client);
76 int ret = 0;
77 u8 tmp;
78
79 if (reg >= ISL29003_NUM_CACHABLE_REGS)
80 return -EINVAL;
81
82 mutex_lock(&data->lock);
83
84 tmp = data->reg_cache[reg];
85 tmp &= ~mask;
86 tmp |= val << shift;
87
88 ret = i2c_smbus_write_byte_data(client, reg, tmp);
89 if (!ret)
90 data->reg_cache[reg] = tmp;
91
92 mutex_unlock(&data->lock);
93 return ret;
94 }
95
96 /*
97 * internally used functions
98 */
99
100 /* range */
isl29003_get_range(struct i2c_client * client)101 static int isl29003_get_range(struct i2c_client *client)
102 {
103 return __isl29003_read_reg(client, ISL29003_REG_CONTROL,
104 ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT);
105 }
106
isl29003_set_range(struct i2c_client * client,int range)107 static int isl29003_set_range(struct i2c_client *client, int range)
108 {
109 return __isl29003_write_reg(client, ISL29003_REG_CONTROL,
110 ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT, range);
111 }
112
113 /* resolution */
isl29003_get_resolution(struct i2c_client * client)114 static int isl29003_get_resolution(struct i2c_client *client)
115 {
116 return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
117 ISL29003_RES_MASK, ISL29003_RES_SHIFT);
118 }
119
isl29003_set_resolution(struct i2c_client * client,int res)120 static int isl29003_set_resolution(struct i2c_client *client, int res)
121 {
122 return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
123 ISL29003_RES_MASK, ISL29003_RES_SHIFT, res);
124 }
125
126 /* mode */
isl29003_get_mode(struct i2c_client * client)127 static int isl29003_get_mode(struct i2c_client *client)
128 {
129 return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
130 ISL29003_MODE_MASK, ISL29003_MODE_SHIFT);
131 }
132
isl29003_set_mode(struct i2c_client * client,int mode)133 static int isl29003_set_mode(struct i2c_client *client, int mode)
134 {
135 return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
136 ISL29003_MODE_MASK, ISL29003_MODE_SHIFT, mode);
137 }
138
139 /* power_state */
isl29003_set_power_state(struct i2c_client * client,int state)140 static int isl29003_set_power_state(struct i2c_client *client, int state)
141 {
142 return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
143 ISL29003_ADC_ENABLED | ISL29003_ADC_PD, 0,
144 state ? ISL29003_ADC_ENABLED : ISL29003_ADC_PD);
145 }
146
isl29003_get_power_state(struct i2c_client * client)147 static int isl29003_get_power_state(struct i2c_client *client)
148 {
149 struct isl29003_data *data = i2c_get_clientdata(client);
150 u8 cmdreg = data->reg_cache[ISL29003_REG_COMMAND];
151
152 return ~cmdreg & ISL29003_ADC_PD;
153 }
154
isl29003_get_adc_value(struct i2c_client * client)155 static int isl29003_get_adc_value(struct i2c_client *client)
156 {
157 struct isl29003_data *data = i2c_get_clientdata(client);
158 int lsb, msb, range, bitdepth;
159
160 mutex_lock(&data->lock);
161 lsb = i2c_smbus_read_byte_data(client, ISL29003_REG_LSB_SENSOR);
162
163 if (lsb < 0) {
164 mutex_unlock(&data->lock);
165 return lsb;
166 }
167
168 msb = i2c_smbus_read_byte_data(client, ISL29003_REG_MSB_SENSOR);
169 mutex_unlock(&data->lock);
170
171 if (msb < 0)
172 return msb;
173
174 range = isl29003_get_range(client);
175 bitdepth = (4 - isl29003_get_resolution(client)) * 4;
176 return (((msb << 8) | lsb) * gain_range[range]) >> bitdepth;
177 }
178
179 /*
180 * sysfs layer
181 */
182
183 /* range */
isl29003_show_range(struct device * dev,struct device_attribute * attr,char * buf)184 static ssize_t isl29003_show_range(struct device *dev,
185 struct device_attribute *attr, char *buf)
186 {
187 struct i2c_client *client = to_i2c_client(dev);
188
189 return sysfs_emit(buf, "%i\n", isl29003_get_range(client));
190 }
191
isl29003_store_range(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)192 static ssize_t isl29003_store_range(struct device *dev,
193 struct device_attribute *attr,
194 const char *buf, size_t count)
195 {
196 struct i2c_client *client = to_i2c_client(dev);
197 unsigned long val;
198 int ret;
199
200 ret = kstrtoul(buf, 10, &val);
201 if (ret)
202 return ret;
203
204 if (val > 3)
205 return -EINVAL;
206
207 ret = isl29003_set_range(client, val);
208 if (ret < 0)
209 return ret;
210
211 return count;
212 }
213
214 static DEVICE_ATTR(range, S_IWUSR | S_IRUGO,
215 isl29003_show_range, isl29003_store_range);
216
217
218 /* resolution */
isl29003_show_resolution(struct device * dev,struct device_attribute * attr,char * buf)219 static ssize_t isl29003_show_resolution(struct device *dev,
220 struct device_attribute *attr,
221 char *buf)
222 {
223 struct i2c_client *client = to_i2c_client(dev);
224
225 return sysfs_emit(buf, "%d\n", isl29003_get_resolution(client));
226 }
227
isl29003_store_resolution(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)228 static ssize_t isl29003_store_resolution(struct device *dev,
229 struct device_attribute *attr,
230 const char *buf, size_t count)
231 {
232 struct i2c_client *client = to_i2c_client(dev);
233 unsigned long val;
234 int ret;
235
236 ret = kstrtoul(buf, 10, &val);
237 if (ret)
238 return ret;
239
240 if (val > 3)
241 return -EINVAL;
242
243 ret = isl29003_set_resolution(client, val);
244 if (ret < 0)
245 return ret;
246
247 return count;
248 }
249
250 static DEVICE_ATTR(resolution, S_IWUSR | S_IRUGO,
251 isl29003_show_resolution, isl29003_store_resolution);
252
253 /* mode */
isl29003_show_mode(struct device * dev,struct device_attribute * attr,char * buf)254 static ssize_t isl29003_show_mode(struct device *dev,
255 struct device_attribute *attr, char *buf)
256 {
257 struct i2c_client *client = to_i2c_client(dev);
258
259 return sysfs_emit(buf, "%d\n", isl29003_get_mode(client));
260 }
261
isl29003_store_mode(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)262 static 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 ret = kstrtoul(buf, 10, &val);
270 if (ret)
271 return ret;
272
273 if (val > 2)
274 return -EINVAL;
275
276 ret = isl29003_set_mode(client, val);
277 if (ret < 0)
278 return ret;
279
280 return count;
281 }
282
283 static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO,
284 isl29003_show_mode, isl29003_store_mode);
285
286
287 /* power state */
isl29003_show_power_state(struct device * dev,struct device_attribute * attr,char * buf)288 static ssize_t isl29003_show_power_state(struct device *dev,
289 struct device_attribute *attr,
290 char *buf)
291 {
292 struct i2c_client *client = to_i2c_client(dev);
293
294 return sysfs_emit(buf, "%d\n", isl29003_get_power_state(client));
295 }
296
isl29003_store_power_state(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)297 static ssize_t isl29003_store_power_state(struct device *dev,
298 struct device_attribute *attr,
299 const char *buf, size_t count)
300 {
301 struct i2c_client *client = to_i2c_client(dev);
302 unsigned long val;
303 int ret;
304
305 ret = kstrtoul(buf, 10, &val);
306 if (ret)
307 return ret;
308
309 if (val > 1)
310 return -EINVAL;
311
312 ret = isl29003_set_power_state(client, val);
313 return ret ? ret : count;
314 }
315
316 static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
317 isl29003_show_power_state, isl29003_store_power_state);
318
319
320 /* lux */
isl29003_show_lux(struct device * dev,struct device_attribute * attr,char * buf)321 static ssize_t isl29003_show_lux(struct device *dev,
322 struct device_attribute *attr, char *buf)
323 {
324 struct i2c_client *client = to_i2c_client(dev);
325
326 /* No LUX data if not operational */
327 if (!isl29003_get_power_state(client))
328 return -EBUSY;
329
330 return sysfs_emit(buf, "%d\n", isl29003_get_adc_value(client));
331 }
332
333 static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL);
334
335 static struct attribute *isl29003_attributes[] = {
336 &dev_attr_range.attr,
337 &dev_attr_resolution.attr,
338 &dev_attr_mode.attr,
339 &dev_attr_power_state.attr,
340 &dev_attr_lux.attr,
341 NULL
342 };
343
344 static const struct attribute_group isl29003_attr_group = {
345 .attrs = isl29003_attributes,
346 };
347
isl29003_init_client(struct i2c_client * client)348 static int isl29003_init_client(struct i2c_client *client)
349 {
350 struct isl29003_data *data = i2c_get_clientdata(client);
351 int i;
352
353 /* read all the registers once to fill the cache.
354 * if one of the reads fails, we consider the init failed */
355 for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) {
356 int v = i2c_smbus_read_byte_data(client, i);
357
358 if (v < 0)
359 return -ENODEV;
360
361 data->reg_cache[i] = v;
362 }
363
364 /* set defaults */
365 isl29003_set_range(client, 0);
366 isl29003_set_resolution(client, 0);
367 isl29003_set_mode(client, 0);
368 isl29003_set_power_state(client, 0);
369
370 return 0;
371 }
372
373 /*
374 * I2C layer
375 */
376
isl29003_probe(struct i2c_client * client)377 static int isl29003_probe(struct i2c_client *client)
378 {
379 struct i2c_adapter *adapter = client->adapter;
380 struct isl29003_data *data;
381 int err = 0;
382
383 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
384 return -EIO;
385
386 data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL);
387 if (!data)
388 return -ENOMEM;
389
390 data->client = client;
391 i2c_set_clientdata(client, data);
392 mutex_init(&data->lock);
393
394 /* initialize the ISL29003 chip */
395 err = isl29003_init_client(client);
396 if (err)
397 goto exit_kfree;
398
399 /* register sysfs hooks */
400 err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group);
401 if (err)
402 goto exit_kfree;
403
404 dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION);
405 return 0;
406
407 exit_kfree:
408 kfree(data);
409 return err;
410 }
411
isl29003_remove(struct i2c_client * client)412 static void isl29003_remove(struct i2c_client *client)
413 {
414 sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group);
415 isl29003_set_power_state(client, 0);
416 kfree(i2c_get_clientdata(client));
417 }
418
419 #ifdef CONFIG_PM_SLEEP
isl29003_suspend(struct device * dev)420 static int isl29003_suspend(struct device *dev)
421 {
422 struct i2c_client *client = to_i2c_client(dev);
423 struct isl29003_data *data = i2c_get_clientdata(client);
424
425 data->power_state_before_suspend = isl29003_get_power_state(client);
426 return isl29003_set_power_state(client, 0);
427 }
428
isl29003_resume(struct device * dev)429 static int isl29003_resume(struct device *dev)
430 {
431 int i;
432 struct i2c_client *client = to_i2c_client(dev);
433 struct isl29003_data *data = i2c_get_clientdata(client);
434
435 /* restore registers from cache */
436 for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++)
437 if (i2c_smbus_write_byte_data(client, i, data->reg_cache[i]))
438 return -EIO;
439
440 return isl29003_set_power_state(client,
441 data->power_state_before_suspend);
442 }
443
444 static SIMPLE_DEV_PM_OPS(isl29003_pm_ops, isl29003_suspend, isl29003_resume);
445 #define ISL29003_PM_OPS (&isl29003_pm_ops)
446
447 #else
448 #define ISL29003_PM_OPS NULL
449 #endif /* CONFIG_PM_SLEEP */
450
451 static const struct i2c_device_id isl29003_id[] = {
452 { "isl29003", 0 },
453 {}
454 };
455 MODULE_DEVICE_TABLE(i2c, isl29003_id);
456
457 static struct i2c_driver isl29003_driver = {
458 .driver = {
459 .name = ISL29003_DRV_NAME,
460 .pm = ISL29003_PM_OPS,
461 },
462 .probe = isl29003_probe,
463 .remove = isl29003_remove,
464 .id_table = isl29003_id,
465 };
466
467 module_i2c_driver(isl29003_driver);
468
469 MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
470 MODULE_DESCRIPTION("ISL29003 ambient light sensor driver");
471 MODULE_LICENSE("GPL v2");
472 MODULE_VERSION(DRIVER_VERSION);
473