summaryrefslogtreecommitdiff
path: root/drivers/misc/isl29003.c
blob: 147b58f7968da8fca5b9ed2ed47eacaebf19c1bc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  isl29003.c - Linux kernel module for
 * 	Intersil ISL29003 ambient light sensor
 *
 *  See file:Documentation/misc-devices/isl29003.rst
 *
 *  Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
 *
 *  Based on code written by
 *  	Rodolfo Giometti <giometti@linux.it>
 *  	Eurotech S.p.A. <info@eurotech.it>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/delay.h>

#define ISL29003_DRV_NAME	"isl29003"
#define DRIVER_VERSION		"1.0"

#define ISL29003_REG_COMMAND		0x00
#define ISL29003_ADC_ENABLED		(1 << 7)
#define ISL29003_ADC_PD			(1 << 6)
#define ISL29003_TIMING_INT		(1 << 5)
#define ISL29003_MODE_SHIFT		(2)
#define ISL29003_MODE_MASK		(0x3 << ISL29003_MODE_SHIFT)
#define ISL29003_RES_SHIFT		(0)
#define ISL29003_RES_MASK		(0x3 << ISL29003_RES_SHIFT)

#define ISL29003_REG_CONTROL		0x01
#define ISL29003_INT_FLG		(1 << 5)
#define ISL29003_RANGE_SHIFT		(2)
#define ISL29003_RANGE_MASK		(0x3 << ISL29003_RANGE_SHIFT)
#define ISL29003_INT_PERSISTS_SHIFT	(0)
#define ISL29003_INT_PERSISTS_MASK	(0xf << ISL29003_INT_PERSISTS_SHIFT)

#define ISL29003_REG_IRQ_THRESH_HI	0x02
#define ISL29003_REG_IRQ_THRESH_LO	0x03
#define ISL29003_REG_LSB_SENSOR		0x04
#define ISL29003_REG_MSB_SENSOR		0x05
#define ISL29003_REG_LSB_TIMER		0x06
#define ISL29003_REG_MSB_TIMER		0x07

#define ISL29003_NUM_CACHABLE_REGS	4

struct isl29003_data {
	struct i2c_client *client;
	struct mutex lock;
	u8 reg_cache[ISL29003_NUM_CACHABLE_REGS];
	u8 power_state_before_suspend;
};

static int gain_range[] = {
	1000, 4000, 16000, 64000
};

/*
 * register access helpers
 */

static int __isl29003_read_reg(struct i2c_client *client,
			       u32 reg, u8 mask, u8 shift)
{
	struct isl29003_data *data = i2c_get_clientdata(client);

	return (data->reg_cache[reg] & mask) >> shift;
}

static int __isl29003_write_reg(struct i2c_client *client,
				u32 reg, u8 mask, u8 shift, u8 val)
{
	struct isl29003_data *data = i2c_get_clientdata(client);
	int ret = 0;
	u8 tmp;

	if (reg >= ISL29003_NUM_CACHABLE_REGS)
		return -EINVAL;

	mutex_lock(&data->lock);

	tmp = data->reg_cache[reg];
	tmp &= ~mask;
	tmp |= val << shift;

	ret = i2c_smbus_write_byte_data(client, reg, tmp);
	if (!ret)
		data->reg_cache[reg] = tmp;

	mutex_unlock(&data->lock);
	return ret;
}

/*
 * internally used functions
 */

/* range */
static int isl29003_get_range(struct i2c_client *client)
{
	return __isl29003_read_reg(client, ISL29003_REG_CONTROL,
		ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT);
}

static int isl29003_set_range(struct i2c_client *client, int range)
{
	return __isl29003_write_reg(client, ISL29003_REG_CONTROL,
		ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT, range);
}

/* resolution */
static int isl29003_get_resolution(struct i2c_client *client)
{
	return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
		ISL29003_RES_MASK, ISL29003_RES_SHIFT);
}

static int isl29003_set_resolution(struct i2c_client *client, int res)
{
	return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
		ISL29003_RES_MASK, ISL29003_RES_SHIFT, res);
}

/* mode */
static int isl29003_get_mode(struct i2c_client *client)
{
	return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
		ISL29003_MODE_MASK, ISL29003_MODE_SHIFT);
}

static int isl29003_set_mode(struct i2c_client *client, int mode)
{
	return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
		ISL29003_MODE_MASK, ISL29003_MODE_SHIFT, mode);
}

/* power_state */
static int isl29003_set_power_state(struct i2c_client *client, int state)
{
	return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
				ISL29003_ADC_ENABLED | ISL29003_ADC_PD, 0,
				state ? ISL29003_ADC_ENABLED : ISL29003_ADC_PD);
}

static int isl29003_get_power_state(struct i2c_client *client)
{
	struct isl29003_data *data = i2c_get_clientdata(client);
	u8 cmdreg = data->reg_cache[ISL29003_REG_COMMAND];

	return ~cmdreg & ISL29003_ADC_PD;
}

static int isl29003_get_adc_value(struct i2c_client *client)
{
	struct isl29003_data *data = i2c_get_clientdata(client);
	int lsb, msb, range, bitdepth;

	mutex_lock(&data->lock);
	lsb = i2c_smbus_read_byte_data(client, ISL29003_REG_LSB_SENSOR);

	if (lsb < 0) {
		mutex_unlock(&data->lock);
		return lsb;
	}

	msb = i2c_smbus_read_byte_data(client, ISL29003_REG_MSB_SENSOR);
	mutex_unlock(&data->lock);

	if (msb < 0)
		return msb;

	range = isl29003_get_range(client);
	bitdepth = (4 - isl29003_get_resolution(client)) * 4;
	return (((msb << 8) | lsb) * gain_range[range]) >> bitdepth;
}

/*
 * sysfs layer
 */

/* range */
static ssize_t isl29003_show_range(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	return sysfs_emit(buf, "%i\n", isl29003_get_range(client));
}

static ssize_t isl29003_store_range(struct device *dev,
				    struct device_attribute *attr,
				    const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long val;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;

	if (val > 3)
		return -EINVAL;

	ret = isl29003_set_range(client, val);
	if (ret < 0)
		return ret;

	return count;
}

static DEVICE_ATTR(range, S_IWUSR | S_IRUGO,
		   isl29003_show_range, isl29003_store_range);


/* resolution */
static ssize_t isl29003_show_resolution(struct device *dev,
					struct device_attribute *attr,
					char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	return sysfs_emit(buf, "%d\n", isl29003_get_resolution(client));
}

static ssize_t isl29003_store_resolution(struct device *dev,
					 struct device_attribute *attr,
					 const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long val;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;

	if (val > 3)
		return -EINVAL;

	ret = isl29003_set_resolution(client, val);
	if (ret < 0)
		return ret;

	return count;
}

static DEVICE_ATTR(resolution, S_IWUSR | S_IRUGO,
		   isl29003_show_resolution, isl29003_store_resolution);

/* mode */
static ssize_t isl29003_show_mode(struct device *dev,
				  struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	return sysfs_emit(buf, "%d\n", isl29003_get_mode(client));
}

static ssize_t isl29003_store_mode(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long val;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;

	if (val > 2)
		return -EINVAL;

	ret = isl29003_set_mode(client, val);
	if (ret < 0)
		return ret;

	return count;
}

static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO,
		   isl29003_show_mode, isl29003_store_mode);


/* power state */
static ssize_t isl29003_show_power_state(struct device *dev,
					 struct device_attribute *attr,
					 char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	return sysfs_emit(buf, "%d\n", isl29003_get_power_state(client));
}

static ssize_t isl29003_store_power_state(struct device *dev,
					  struct device_attribute *attr,
					  const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long val;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;

	if (val > 1)
		return -EINVAL;

	ret = isl29003_set_power_state(client, val);
	return ret ? ret : count;
}

static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
		   isl29003_show_power_state, isl29003_store_power_state);


/* lux */
static ssize_t isl29003_show_lux(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	/* No LUX data if not operational */
	if (!isl29003_get_power_state(client))
		return -EBUSY;

	return sysfs_emit(buf, "%d\n", isl29003_get_adc_value(client));
}

static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL);

static struct attribute *isl29003_attributes[] = {
	&dev_attr_range.attr,
	&dev_attr_resolution.attr,
	&dev_attr_mode.attr,
	&dev_attr_power_state.attr,
	&dev_attr_lux.attr,
	NULL
};

static const struct attribute_group isl29003_attr_group = {
	.attrs = isl29003_attributes,
};

static int isl29003_init_client(struct i2c_client *client)
{
	struct isl29003_data *data = i2c_get_clientdata(client);
	int i;

	/* read all the registers once to fill the cache.
	 * if one of the reads fails, we consider the init failed */
	for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) {
		int v = i2c_smbus_read_byte_data(client, i);

		if (v < 0)
			return -ENODEV;

		data->reg_cache[i] = v;
	}

	/* set defaults */
	isl29003_set_range(client, 0);
	isl29003_set_resolution(client, 0);
	isl29003_set_mode(client, 0);
	isl29003_set_power_state(client, 0);

	return 0;
}

/*
 * I2C layer
 */

static int isl29003_probe(struct i2c_client *client)
{
	struct i2c_adapter *adapter = client->adapter;
	struct isl29003_data *data;
	int err = 0;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
		return -EIO;

	data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->client = client;
	i2c_set_clientdata(client, data);
	mutex_init(&data->lock);

	/* initialize the ISL29003 chip */
	err = isl29003_init_client(client);
	if (err)
		goto exit_kfree;

	/* register sysfs hooks */
	err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group);
	if (err)
		goto exit_kfree;

	dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION);
	return 0;

exit_kfree:
	kfree(data);
	return err;
}

static void isl29003_remove(struct i2c_client *client)
{
	sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group);
	isl29003_set_power_state(client, 0);
	kfree(i2c_get_clientdata(client));
}

#ifdef CONFIG_PM_SLEEP
static int isl29003_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct isl29003_data *data = i2c_get_clientdata(client);

	data->power_state_before_suspend = isl29003_get_power_state(client);
	return isl29003_set_power_state(client, 0);
}

static int isl29003_resume(struct device *dev)
{
	int i;
	struct i2c_client *client = to_i2c_client(dev);
	struct isl29003_data *data = i2c_get_clientdata(client);

	/* restore registers from cache */
	for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++)
		if (i2c_smbus_write_byte_data(client, i, data->reg_cache[i]))
			return -EIO;

	return isl29003_set_power_state(client,
		data->power_state_before_suspend);
}

static SIMPLE_DEV_PM_OPS(isl29003_pm_ops, isl29003_suspend, isl29003_resume);
#define ISL29003_PM_OPS (&isl29003_pm_ops)

#else
#define ISL29003_PM_OPS NULL
#endif /* CONFIG_PM_SLEEP */

static const struct i2c_device_id isl29003_id[] = {
	{ "isl29003", 0 },
	{}
};
MODULE_DEVICE_TABLE(i2c, isl29003_id);

static struct i2c_driver isl29003_driver = {
	.driver = {
		.name	= ISL29003_DRV_NAME,
		.pm	= ISL29003_PM_OPS,
	},
	.probe_new = isl29003_probe,
	.remove	= isl29003_remove,
	.id_table = isl29003_id,
};

module_i2c_driver(isl29003_driver);

MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
MODULE_DESCRIPTION("ISL29003 ambient light sensor driver");
MODULE_LICENSE("GPL v2");
MODULE_VERSION(DRIVER_VERSION);