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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 <[email protected]>
9 *
10 * Based on code written by
11 * Rodolfo Giometti <[email protected]>
12 * Eurotech S.p.A. <[email protected]>
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
49struct 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
56static int gain_range[] = {
57 1000, 4000, 16000, 64000
58};
59
60/*
61 * register access helpers
62 */
63
64static 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
72static 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 */
101static 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
107static 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 */
114static 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
120static 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 */
127static 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
133static 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 */
140static 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
147static 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
155static 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 */
184static 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
192static 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
214static DEVICE_ATTR(range, S_IWUSR | S_IRUGO,
215 isl29003_show_range, isl29003_store_range);
216
217
218/* resolution */
219static 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
228static 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
250static DEVICE_ATTR(resolution, S_IWUSR | S_IRUGO,
251 isl29003_show_resolution, isl29003_store_resolution);
252
253/* mode */
254static 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
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 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
283static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO,
284 isl29003_show_mode, isl29003_store_mode);
285
286
287/* power state */
288static 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
297static 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
316static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
317 isl29003_show_power_state, isl29003_store_power_state);
318
319
320/* lux */
321static 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
333static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL);
334
335static 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
344static const struct attribute_group isl29003_attr_group = {
345 .attrs = isl29003_attributes,
346};
347
348static 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
377static 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_obj(struct isl29003_data);
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
407exit_kfree:
408 kfree(data);
409 return err;
410}
411
412static 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
420static 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
429static 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
444static 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
451static const struct i2c_device_id isl29003_id[] = {
452 { .name = "isl29003" },
453 { }
454};
455MODULE_DEVICE_TABLE(i2c, isl29003_id);
456
457static 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
467module_i2c_driver(isl29003_driver);
468
469MODULE_AUTHOR("Daniel Mack <[email protected]>");
470MODULE_DESCRIPTION("ISL29003 ambient light sensor driver");
471MODULE_LICENSE("GPL v2");
472MODULE_VERSION(DRIVER_VERSION);