Merge remote-tracking branch 'stable/linux-5.15.y' into rpi-5.15.y
[platform/kernel/linux-rpi.git] / drivers / misc / isl29003.c
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
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
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 */
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
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 */
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
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 */
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
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 */
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
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
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 */
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 sprintf(buf, "%i\n", isl29003_get_range(client));
190 }
191
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 */
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 sprintf(buf, "%d\n", isl29003_get_resolution(client));
226 }
227
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 */
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 sprintf(buf, "%d\n", isl29003_get_mode(client));
260 }
261
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 */
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 sprintf(buf, "%d\n", isl29003_get_power_state(client));
295 }
296
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 */
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 sprintf(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
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
377 static int isl29003_probe(struct i2c_client *client,
378                                     const struct i2c_device_id *id)
379 {
380         struct i2c_adapter *adapter = client->adapter;
381         struct isl29003_data *data;
382         int err = 0;
383
384         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
385                 return -EIO;
386
387         data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL);
388         if (!data)
389                 return -ENOMEM;
390
391         data->client = client;
392         i2c_set_clientdata(client, data);
393         mutex_init(&data->lock);
394
395         /* initialize the ISL29003 chip */
396         err = isl29003_init_client(client);
397         if (err)
398                 goto exit_kfree;
399
400         /* register sysfs hooks */
401         err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group);
402         if (err)
403                 goto exit_kfree;
404
405         dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION);
406         return 0;
407
408 exit_kfree:
409         kfree(data);
410         return err;
411 }
412
413 static int isl29003_remove(struct i2c_client *client)
414 {
415         sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group);
416         isl29003_set_power_state(client, 0);
417         kfree(i2c_get_clientdata(client));
418         return 0;
419 }
420
421 #ifdef CONFIG_PM_SLEEP
422 static int isl29003_suspend(struct device *dev)
423 {
424         struct i2c_client *client = to_i2c_client(dev);
425         struct isl29003_data *data = i2c_get_clientdata(client);
426
427         data->power_state_before_suspend = isl29003_get_power_state(client);
428         return isl29003_set_power_state(client, 0);
429 }
430
431 static int isl29003_resume(struct device *dev)
432 {
433         int i;
434         struct i2c_client *client = to_i2c_client(dev);
435         struct isl29003_data *data = i2c_get_clientdata(client);
436
437         /* restore registers from cache */
438         for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++)
439                 if (i2c_smbus_write_byte_data(client, i, data->reg_cache[i]))
440                         return -EIO;
441
442         return isl29003_set_power_state(client,
443                 data->power_state_before_suspend);
444 }
445
446 static SIMPLE_DEV_PM_OPS(isl29003_pm_ops, isl29003_suspend, isl29003_resume);
447 #define ISL29003_PM_OPS (&isl29003_pm_ops)
448
449 #else
450 #define ISL29003_PM_OPS NULL
451 #endif /* CONFIG_PM_SLEEP */
452
453 static const struct i2c_device_id isl29003_id[] = {
454         { "isl29003", 0 },
455         {}
456 };
457 MODULE_DEVICE_TABLE(i2c, isl29003_id);
458
459 static struct i2c_driver isl29003_driver = {
460         .driver = {
461                 .name   = ISL29003_DRV_NAME,
462                 .pm     = ISL29003_PM_OPS,
463         },
464         .probe  = isl29003_probe,
465         .remove = isl29003_remove,
466         .id_table = isl29003_id,
467 };
468
469 module_i2c_driver(isl29003_driver);
470
471 MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
472 MODULE_DESCRIPTION("ISL29003 ambient light sensor driver");
473 MODULE_LICENSE("GPL v2");
474 MODULE_VERSION(DRIVER_VERSION);