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1/*
2 * tsl2550.c - Linux kernel modules for ambient light sensor
3 *
4 * Copyright (C) 2007 Rodolfo Giometti <giometti@linux.it>
5 * Copyright (C) 2007 Eurotech S.p.A. <info@eurotech.it>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 */
21
22#include <linux/module.h>
23#include <linux/init.h>
24#include <linux/slab.h>
25#include <linux/i2c.h>
26#include <linux/mutex.h>
27
28#define TSL2550_DRV_NAME "tsl2550"
29#define DRIVER_VERSION "1.2"
30
31/*
32 * Defines
33 */
34
35#define TSL2550_POWER_DOWN 0x00
36#define TSL2550_POWER_UP 0x03
37#define TSL2550_STANDARD_RANGE 0x18
38#define TSL2550_EXTENDED_RANGE 0x1d
39#define TSL2550_READ_ADC0 0x43
40#define TSL2550_READ_ADC1 0x83
41
42/*
43 * Structs
44 */
45
46struct tsl2550_data {
47 struct i2c_client *client;
48 struct mutex update_lock;
49
50 unsigned int power_state:1;
51 unsigned int operating_mode:1;
52};
53
54/*
55 * Global data
56 */
57
58static const u8 TSL2550_MODE_RANGE[2] = {
59 TSL2550_STANDARD_RANGE, TSL2550_EXTENDED_RANGE,
60};
61
62/*
63 * Management functions
64 */
65
66static int tsl2550_set_operating_mode(struct i2c_client *client, int mode)
67{
68 struct tsl2550_data *data = i2c_get_clientdata(client);
69
70 int ret = i2c_smbus_write_byte(client, TSL2550_MODE_RANGE[mode]);
71
72 data->operating_mode = mode;
73
74 return ret;
75}
76
77static int tsl2550_set_power_state(struct i2c_client *client, int state)
78{
79 struct tsl2550_data *data = i2c_get_clientdata(client);
80 int ret;
81
82 if (state == 0)
83 ret = i2c_smbus_write_byte(client, TSL2550_POWER_DOWN);
84 else {
85 ret = i2c_smbus_write_byte(client, TSL2550_POWER_UP);
86
87 /* On power up we should reset operating mode also... */
88 tsl2550_set_operating_mode(client, data->operating_mode);
89 }
90
91 data->power_state = state;
92
93 return ret;
94}
95
96static int tsl2550_get_adc_value(struct i2c_client *client, u8 cmd)
97{
98 int ret;
99
100 ret = i2c_smbus_read_byte_data(client, cmd);
101 if (ret < 0)
102 return ret;
103 if (!(ret & 0x80))
104 return -EAGAIN;
105 return ret & 0x7f; /* remove the "valid" bit */
106}
107
108/*
109 * LUX calculation
110 */
111
112#define TSL2550_MAX_LUX 1846
113
114static const u8 ratio_lut[] = {
115 100, 100, 100, 100, 100, 100, 100, 100,
116 100, 100, 100, 100, 100, 100, 99, 99,
117 99, 99, 99, 99, 99, 99, 99, 99,
118 99, 99, 99, 98, 98, 98, 98, 98,
119 98, 98, 97, 97, 97, 97, 97, 96,
120 96, 96, 96, 95, 95, 95, 94, 94,
121 93, 93, 93, 92, 92, 91, 91, 90,
122 89, 89, 88, 87, 87, 86, 85, 84,
123 83, 82, 81, 80, 79, 78, 77, 75,
124 74, 73, 71, 69, 68, 66, 64, 62,
125 60, 58, 56, 54, 52, 49, 47, 44,
126 42, 41, 40, 40, 39, 39, 38, 38,
127 37, 37, 37, 36, 36, 36, 35, 35,
128 35, 35, 34, 34, 34, 34, 33, 33,
129 33, 33, 32, 32, 32, 32, 32, 31,
130 31, 31, 31, 31, 30, 30, 30, 30,
131 30,
132};
133
134static const u16 count_lut[] = {
135 0, 1, 2, 3, 4, 5, 6, 7,
136 8, 9, 10, 11, 12, 13, 14, 15,
137 16, 18, 20, 22, 24, 26, 28, 30,
138 32, 34, 36, 38, 40, 42, 44, 46,
139 49, 53, 57, 61, 65, 69, 73, 77,
140 81, 85, 89, 93, 97, 101, 105, 109,
141 115, 123, 131, 139, 147, 155, 163, 171,
142 179, 187, 195, 203, 211, 219, 227, 235,
143 247, 263, 279, 295, 311, 327, 343, 359,
144 375, 391, 407, 423, 439, 455, 471, 487,
145 511, 543, 575, 607, 639, 671, 703, 735,
146 767, 799, 831, 863, 895, 927, 959, 991,
147 1039, 1103, 1167, 1231, 1295, 1359, 1423, 1487,
148 1551, 1615, 1679, 1743, 1807, 1871, 1935, 1999,
149 2095, 2223, 2351, 2479, 2607, 2735, 2863, 2991,
150 3119, 3247, 3375, 3503, 3631, 3759, 3887, 4015,
151};
152
153/*
154 * This function is described into Taos TSL2550 Designer's Notebook
155 * pages 2, 3.
156 */
157static int tsl2550_calculate_lux(u8 ch0, u8 ch1)
158{
159 unsigned int lux;
160
161 /* Look up count from channel values */
162 u16 c0 = count_lut[ch0];
163 u16 c1 = count_lut[ch1];
164
165 /*
166 * Calculate ratio.
167 * Note: the "128" is a scaling factor
168 */
169 u8 r = 128;
170
171 /* Avoid division by 0 and count 1 cannot be greater than count 0 */
172 if (c1 <= c0)
173 if (c0) {
174 r = c1 * 128 / c0;
175
176 /* Calculate LUX */
177 lux = ((c0 - c1) * ratio_lut[r]) / 256;
178 } else
179 lux = 0;
180 else
181 return -EAGAIN;
182
183 /* LUX range check */
184 return lux > TSL2550_MAX_LUX ? TSL2550_MAX_LUX : lux;
185}
186
187/*
188 * SysFS support
189 */
190
191static ssize_t tsl2550_show_power_state(struct device *dev,
192 struct device_attribute *attr, char *buf)
193{
194 struct tsl2550_data *data = i2c_get_clientdata(to_i2c_client(dev));
195
196 return sprintf(buf, "%u\n", data->power_state);
197}
198
199static ssize_t tsl2550_store_power_state(struct device *dev,
200 struct device_attribute *attr, const char *buf, size_t count)
201{
202 struct i2c_client *client = to_i2c_client(dev);
203 struct tsl2550_data *data = i2c_get_clientdata(client);
204 unsigned long val = simple_strtoul(buf, NULL, 10);
205 int ret;
206
207 if (val < 0 || val > 1)
208 return -EINVAL;
209
210 mutex_lock(&data->update_lock);
211 ret = tsl2550_set_power_state(client, val);
212 mutex_unlock(&data->update_lock);
213
214 if (ret < 0)
215 return ret;
216
217 return count;
218}
219
220static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
221 tsl2550_show_power_state, tsl2550_store_power_state);
222
223static ssize_t tsl2550_show_operating_mode(struct device *dev,
224 struct device_attribute *attr, char *buf)
225{
226 struct tsl2550_data *data = i2c_get_clientdata(to_i2c_client(dev));
227
228 return sprintf(buf, "%u\n", data->operating_mode);
229}
230
231static ssize_t tsl2550_store_operating_mode(struct device *dev,
232 struct device_attribute *attr, const char *buf, size_t count)
233{
234 struct i2c_client *client = to_i2c_client(dev);
235 struct tsl2550_data *data = i2c_get_clientdata(client);
236 unsigned long val = simple_strtoul(buf, NULL, 10);
237 int ret;
238
239 if (val < 0 || val > 1)
240 return -EINVAL;
241
242 if (data->power_state == 0)
243 return -EBUSY;
244
245 mutex_lock(&data->update_lock);
246 ret = tsl2550_set_operating_mode(client, val);
247 mutex_unlock(&data->update_lock);
248
249 if (ret < 0)
250 return ret;
251
252 return count;
253}
254
255static DEVICE_ATTR(operating_mode, S_IWUSR | S_IRUGO,
256 tsl2550_show_operating_mode, tsl2550_store_operating_mode);
257
258static ssize_t __tsl2550_show_lux(struct i2c_client *client, char *buf)
259{
260 struct tsl2550_data *data = i2c_get_clientdata(client);
261 u8 ch0, ch1;
262 int ret;
263
264 ret = tsl2550_get_adc_value(client, TSL2550_READ_ADC0);
265 if (ret < 0)
266 return ret;
267 ch0 = ret;
268
269 ret = tsl2550_get_adc_value(client, TSL2550_READ_ADC1);
270 if (ret < 0)
271 return ret;
272 ch1 = ret;
273
274 /* Do the job */
275 ret = tsl2550_calculate_lux(ch0, ch1);
276 if (ret < 0)
277 return ret;
278 if (data->operating_mode == 1)
279 ret *= 5;
280
281 return sprintf(buf, "%d\n", ret);
282}
283
284static ssize_t tsl2550_show_lux1_input(struct device *dev,
285 struct device_attribute *attr, char *buf)
286{
287 struct i2c_client *client = to_i2c_client(dev);
288 struct tsl2550_data *data = i2c_get_clientdata(client);
289 int ret;
290
291 /* No LUX data if not operational */
292 if (!data->power_state)
293 return -EBUSY;
294
295 mutex_lock(&data->update_lock);
296 ret = __tsl2550_show_lux(client, buf);
297 mutex_unlock(&data->update_lock);
298
299 return ret;
300}
301
302static DEVICE_ATTR(lux1_input, S_IRUGO,
303 tsl2550_show_lux1_input, NULL);
304
305static struct attribute *tsl2550_attributes[] = {
306 &dev_attr_power_state.attr,
307 &dev_attr_operating_mode.attr,
308 &dev_attr_lux1_input.attr,
309 NULL
310};
311
312static const struct attribute_group tsl2550_attr_group = {
313 .attrs = tsl2550_attributes,
314};
315
316/*
317 * Initialization function
318 */
319
320static int tsl2550_init_client(struct i2c_client *client)
321{
322 struct tsl2550_data *data = i2c_get_clientdata(client);
323 int err;
324
325 /*
326 * Probe the chip. To do so we try to power up the device and then to
327 * read back the 0x03 code
328 */
329 err = i2c_smbus_read_byte_data(client, TSL2550_POWER_UP);
330 if (err < 0)
331 return err;
332 if (err != TSL2550_POWER_UP)
333 return -ENODEV;
334 data->power_state = 1;
335
336 /* Set the default operating mode */
337 err = i2c_smbus_write_byte(client,
338 TSL2550_MODE_RANGE[data->operating_mode]);
339 if (err < 0)
340 return err;
341
342 return 0;
343}
344
345/*
346 * I2C init/probing/exit functions
347 */
348
349static struct i2c_driver tsl2550_driver;
350static int __devinit tsl2550_probe(struct i2c_client *client,
351 const struct i2c_device_id *id)
352{
353 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
354 struct tsl2550_data *data;
355 int *opmode, err = 0;
356
357 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE
358 | I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
359 err = -EIO;
360 goto exit;
361 }
362
363 data = kzalloc(sizeof(struct tsl2550_data), GFP_KERNEL);
364 if (!data) {
365 err = -ENOMEM;
366 goto exit;
367 }
368 data->client = client;
369 i2c_set_clientdata(client, data);
370
371 /* Check platform data */
372 opmode = client->dev.platform_data;
373 if (opmode) {
374 if (*opmode < 0 || *opmode > 1) {
375 dev_err(&client->dev, "invalid operating_mode (%d)\n",
376 *opmode);
377 err = -EINVAL;
378 goto exit_kfree;
379 }
380 data->operating_mode = *opmode;
381 } else
382 data->operating_mode = 0; /* default mode is standard */
383 dev_info(&client->dev, "%s operating mode\n",
384 data->operating_mode ? "extended" : "standard");
385
386 mutex_init(&data->update_lock);
387
388 /* Initialize the TSL2550 chip */
389 err = tsl2550_init_client(client);
390 if (err)
391 goto exit_kfree;
392
393 /* Register sysfs hooks */
394 err = sysfs_create_group(&client->dev.kobj, &tsl2550_attr_group);
395 if (err)
396 goto exit_kfree;
397
398 dev_info(&client->dev, "support ver. %s enabled\n", DRIVER_VERSION);
399
400 return 0;
401
402exit_kfree:
403 kfree(data);
404exit:
405 return err;
406}
407
408static int __devexit tsl2550_remove(struct i2c_client *client)
409{
410 sysfs_remove_group(&client->dev.kobj, &tsl2550_attr_group);
411
412 /* Power down the device */
413 tsl2550_set_power_state(client, 0);
414
415 kfree(i2c_get_clientdata(client));
416
417 return 0;
418}
419
420#ifdef CONFIG_PM
421
422static int tsl2550_suspend(struct i2c_client *client, pm_message_t mesg)
423{
424 return tsl2550_set_power_state(client, 0);
425}
426
427static int tsl2550_resume(struct i2c_client *client)
428{
429 return tsl2550_set_power_state(client, 1);
430}
431
432#else
433
434#define tsl2550_suspend NULL
435#define tsl2550_resume NULL
436
437#endif /* CONFIG_PM */
438
439static const struct i2c_device_id tsl2550_id[] = {
440 { "tsl2550", 0 },
441 { }
442};
443MODULE_DEVICE_TABLE(i2c, tsl2550_id);
444
445static struct i2c_driver tsl2550_driver = {
446 .driver = {
447 .name = TSL2550_DRV_NAME,
448 .owner = THIS_MODULE,
449 },
450 .suspend = tsl2550_suspend,
451 .resume = tsl2550_resume,
452 .probe = tsl2550_probe,
453 .remove = __devexit_p(tsl2550_remove),
454 .id_table = tsl2550_id,
455};
456
457static int __init tsl2550_init(void)
458{
459 return i2c_add_driver(&tsl2550_driver);
460}
461
462static void __exit tsl2550_exit(void)
463{
464 i2c_del_driver(&tsl2550_driver);
465}
466
467MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
468MODULE_DESCRIPTION("TSL2550 ambient light sensor driver");
469MODULE_LICENSE("GPL");
470MODULE_VERSION(DRIVER_VERSION);
471
472module_init(tsl2550_init);
473module_exit(tsl2550_exit);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * tsl2550.c - Linux kernel modules for ambient light sensor
4 *
5 * Copyright (C) 2007 Rodolfo Giometti <giometti@linux.it>
6 * Copyright (C) 2007 Eurotech S.p.A. <info@eurotech.it>
7 */
8
9#include <linux/module.h>
10#include <linux/slab.h>
11#include <linux/i2c.h>
12#include <linux/mutex.h>
13
14#define TSL2550_DRV_NAME "tsl2550"
15#define DRIVER_VERSION "1.2"
16
17/*
18 * Defines
19 */
20
21#define TSL2550_POWER_DOWN 0x00
22#define TSL2550_POWER_UP 0x03
23#define TSL2550_STANDARD_RANGE 0x18
24#define TSL2550_EXTENDED_RANGE 0x1d
25#define TSL2550_READ_ADC0 0x43
26#define TSL2550_READ_ADC1 0x83
27
28/*
29 * Structs
30 */
31
32struct tsl2550_data {
33 struct i2c_client *client;
34 struct mutex update_lock;
35
36 unsigned int power_state:1;
37 unsigned int operating_mode:1;
38};
39
40/*
41 * Global data
42 */
43
44static const u8 TSL2550_MODE_RANGE[2] = {
45 TSL2550_STANDARD_RANGE, TSL2550_EXTENDED_RANGE,
46};
47
48/*
49 * Management functions
50 */
51
52static int tsl2550_set_operating_mode(struct i2c_client *client, int mode)
53{
54 struct tsl2550_data *data = i2c_get_clientdata(client);
55
56 int ret = i2c_smbus_write_byte(client, TSL2550_MODE_RANGE[mode]);
57
58 data->operating_mode = mode;
59
60 return ret;
61}
62
63static int tsl2550_set_power_state(struct i2c_client *client, int state)
64{
65 struct tsl2550_data *data = i2c_get_clientdata(client);
66 int ret;
67
68 if (state == 0)
69 ret = i2c_smbus_write_byte(client, TSL2550_POWER_DOWN);
70 else {
71 ret = i2c_smbus_write_byte(client, TSL2550_POWER_UP);
72
73 /* On power up we should reset operating mode also... */
74 tsl2550_set_operating_mode(client, data->operating_mode);
75 }
76
77 data->power_state = state;
78
79 return ret;
80}
81
82static int tsl2550_get_adc_value(struct i2c_client *client, u8 cmd)
83{
84 int ret;
85
86 ret = i2c_smbus_read_byte_data(client, cmd);
87 if (ret < 0)
88 return ret;
89 if (!(ret & 0x80))
90 return -EAGAIN;
91 return ret & 0x7f; /* remove the "valid" bit */
92}
93
94/*
95 * LUX calculation
96 */
97
98#define TSL2550_MAX_LUX 1846
99
100static const u8 ratio_lut[] = {
101 100, 100, 100, 100, 100, 100, 100, 100,
102 100, 100, 100, 100, 100, 100, 99, 99,
103 99, 99, 99, 99, 99, 99, 99, 99,
104 99, 99, 99, 98, 98, 98, 98, 98,
105 98, 98, 97, 97, 97, 97, 97, 96,
106 96, 96, 96, 95, 95, 95, 94, 94,
107 93, 93, 93, 92, 92, 91, 91, 90,
108 89, 89, 88, 87, 87, 86, 85, 84,
109 83, 82, 81, 80, 79, 78, 77, 75,
110 74, 73, 71, 69, 68, 66, 64, 62,
111 60, 58, 56, 54, 52, 49, 47, 44,
112 42, 41, 40, 40, 39, 39, 38, 38,
113 37, 37, 37, 36, 36, 36, 35, 35,
114 35, 35, 34, 34, 34, 34, 33, 33,
115 33, 33, 32, 32, 32, 32, 32, 31,
116 31, 31, 31, 31, 30, 30, 30, 30,
117 30,
118};
119
120static const u16 count_lut[] = {
121 0, 1, 2, 3, 4, 5, 6, 7,
122 8, 9, 10, 11, 12, 13, 14, 15,
123 16, 18, 20, 22, 24, 26, 28, 30,
124 32, 34, 36, 38, 40, 42, 44, 46,
125 49, 53, 57, 61, 65, 69, 73, 77,
126 81, 85, 89, 93, 97, 101, 105, 109,
127 115, 123, 131, 139, 147, 155, 163, 171,
128 179, 187, 195, 203, 211, 219, 227, 235,
129 247, 263, 279, 295, 311, 327, 343, 359,
130 375, 391, 407, 423, 439, 455, 471, 487,
131 511, 543, 575, 607, 639, 671, 703, 735,
132 767, 799, 831, 863, 895, 927, 959, 991,
133 1039, 1103, 1167, 1231, 1295, 1359, 1423, 1487,
134 1551, 1615, 1679, 1743, 1807, 1871, 1935, 1999,
135 2095, 2223, 2351, 2479, 2607, 2735, 2863, 2991,
136 3119, 3247, 3375, 3503, 3631, 3759, 3887, 4015,
137};
138
139/*
140 * This function is described into Taos TSL2550 Designer's Notebook
141 * pages 2, 3.
142 */
143static int tsl2550_calculate_lux(u8 ch0, u8 ch1)
144{
145 unsigned int lux;
146
147 /* Look up count from channel values */
148 u16 c0 = count_lut[ch0];
149 u16 c1 = count_lut[ch1];
150
151 /* Avoid division by 0 and count 1 cannot be greater than count 0 */
152 if (c1 <= c0)
153 if (c0) {
154 /*
155 * Calculate ratio.
156 * Note: the "128" is a scaling factor
157 */
158 u8 r = c1 * 128 / c0;
159
160 /* Calculate LUX */
161 lux = ((c0 - c1) * ratio_lut[r]) / 256;
162 } else
163 lux = 0;
164 else
165 return 0;
166
167 /* LUX range check */
168 return lux > TSL2550_MAX_LUX ? TSL2550_MAX_LUX : lux;
169}
170
171/*
172 * SysFS support
173 */
174
175static ssize_t tsl2550_show_power_state(struct device *dev,
176 struct device_attribute *attr, char *buf)
177{
178 struct tsl2550_data *data = i2c_get_clientdata(to_i2c_client(dev));
179
180 return sprintf(buf, "%u\n", data->power_state);
181}
182
183static ssize_t tsl2550_store_power_state(struct device *dev,
184 struct device_attribute *attr, const char *buf, size_t count)
185{
186 struct i2c_client *client = to_i2c_client(dev);
187 struct tsl2550_data *data = i2c_get_clientdata(client);
188 unsigned long val = simple_strtoul(buf, NULL, 10);
189 int ret;
190
191 if (val > 1)
192 return -EINVAL;
193
194 mutex_lock(&data->update_lock);
195 ret = tsl2550_set_power_state(client, val);
196 mutex_unlock(&data->update_lock);
197
198 if (ret < 0)
199 return ret;
200
201 return count;
202}
203
204static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
205 tsl2550_show_power_state, tsl2550_store_power_state);
206
207static ssize_t tsl2550_show_operating_mode(struct device *dev,
208 struct device_attribute *attr, char *buf)
209{
210 struct tsl2550_data *data = i2c_get_clientdata(to_i2c_client(dev));
211
212 return sprintf(buf, "%u\n", data->operating_mode);
213}
214
215static ssize_t tsl2550_store_operating_mode(struct device *dev,
216 struct device_attribute *attr, const char *buf, size_t count)
217{
218 struct i2c_client *client = to_i2c_client(dev);
219 struct tsl2550_data *data = i2c_get_clientdata(client);
220 unsigned long val = simple_strtoul(buf, NULL, 10);
221 int ret;
222
223 if (val > 1)
224 return -EINVAL;
225
226 if (data->power_state == 0)
227 return -EBUSY;
228
229 mutex_lock(&data->update_lock);
230 ret = tsl2550_set_operating_mode(client, val);
231 mutex_unlock(&data->update_lock);
232
233 if (ret < 0)
234 return ret;
235
236 return count;
237}
238
239static DEVICE_ATTR(operating_mode, S_IWUSR | S_IRUGO,
240 tsl2550_show_operating_mode, tsl2550_store_operating_mode);
241
242static ssize_t __tsl2550_show_lux(struct i2c_client *client, char *buf)
243{
244 struct tsl2550_data *data = i2c_get_clientdata(client);
245 u8 ch0, ch1;
246 int ret;
247
248 ret = tsl2550_get_adc_value(client, TSL2550_READ_ADC0);
249 if (ret < 0)
250 return ret;
251 ch0 = ret;
252
253 ret = tsl2550_get_adc_value(client, TSL2550_READ_ADC1);
254 if (ret < 0)
255 return ret;
256 ch1 = ret;
257
258 /* Do the job */
259 ret = tsl2550_calculate_lux(ch0, ch1);
260 if (ret < 0)
261 return ret;
262 if (data->operating_mode == 1)
263 ret *= 5;
264
265 return sprintf(buf, "%d\n", ret);
266}
267
268static ssize_t tsl2550_show_lux1_input(struct device *dev,
269 struct device_attribute *attr, char *buf)
270{
271 struct i2c_client *client = to_i2c_client(dev);
272 struct tsl2550_data *data = i2c_get_clientdata(client);
273 int ret;
274
275 /* No LUX data if not operational */
276 if (!data->power_state)
277 return -EBUSY;
278
279 mutex_lock(&data->update_lock);
280 ret = __tsl2550_show_lux(client, buf);
281 mutex_unlock(&data->update_lock);
282
283 return ret;
284}
285
286static DEVICE_ATTR(lux1_input, S_IRUGO,
287 tsl2550_show_lux1_input, NULL);
288
289static struct attribute *tsl2550_attributes[] = {
290 &dev_attr_power_state.attr,
291 &dev_attr_operating_mode.attr,
292 &dev_attr_lux1_input.attr,
293 NULL
294};
295
296static const struct attribute_group tsl2550_attr_group = {
297 .attrs = tsl2550_attributes,
298};
299
300/*
301 * Initialization function
302 */
303
304static int tsl2550_init_client(struct i2c_client *client)
305{
306 struct tsl2550_data *data = i2c_get_clientdata(client);
307 int err;
308
309 /*
310 * Probe the chip. To do so we try to power up the device and then to
311 * read back the 0x03 code
312 */
313 err = i2c_smbus_read_byte_data(client, TSL2550_POWER_UP);
314 if (err < 0)
315 return err;
316 if (err != TSL2550_POWER_UP)
317 return -ENODEV;
318 data->power_state = 1;
319
320 /* Set the default operating mode */
321 err = i2c_smbus_write_byte(client,
322 TSL2550_MODE_RANGE[data->operating_mode]);
323 if (err < 0)
324 return err;
325
326 return 0;
327}
328
329/*
330 * I2C init/probing/exit functions
331 */
332
333static struct i2c_driver tsl2550_driver;
334static int tsl2550_probe(struct i2c_client *client)
335{
336 struct i2c_adapter *adapter = client->adapter;
337 struct tsl2550_data *data;
338 int *opmode, err = 0;
339
340 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE
341 | I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
342 err = -EIO;
343 goto exit;
344 }
345
346 data = kzalloc(sizeof(struct tsl2550_data), GFP_KERNEL);
347 if (!data) {
348 err = -ENOMEM;
349 goto exit;
350 }
351 data->client = client;
352 i2c_set_clientdata(client, data);
353
354 /* Check platform data */
355 opmode = client->dev.platform_data;
356 if (opmode) {
357 if (*opmode < 0 || *opmode > 1) {
358 dev_err(&client->dev, "invalid operating_mode (%d)\n",
359 *opmode);
360 err = -EINVAL;
361 goto exit_kfree;
362 }
363 data->operating_mode = *opmode;
364 } else
365 data->operating_mode = 0; /* default mode is standard */
366 dev_info(&client->dev, "%s operating mode\n",
367 data->operating_mode ? "extended" : "standard");
368
369 mutex_init(&data->update_lock);
370
371 /* Initialize the TSL2550 chip */
372 err = tsl2550_init_client(client);
373 if (err)
374 goto exit_kfree;
375
376 /* Register sysfs hooks */
377 err = sysfs_create_group(&client->dev.kobj, &tsl2550_attr_group);
378 if (err)
379 goto exit_kfree;
380
381 dev_info(&client->dev, "support ver. %s enabled\n", DRIVER_VERSION);
382
383 return 0;
384
385exit_kfree:
386 kfree(data);
387exit:
388 return err;
389}
390
391static void tsl2550_remove(struct i2c_client *client)
392{
393 sysfs_remove_group(&client->dev.kobj, &tsl2550_attr_group);
394
395 /* Power down the device */
396 tsl2550_set_power_state(client, 0);
397
398 kfree(i2c_get_clientdata(client));
399}
400
401#ifdef CONFIG_PM_SLEEP
402
403static int tsl2550_suspend(struct device *dev)
404{
405 return tsl2550_set_power_state(to_i2c_client(dev), 0);
406}
407
408static int tsl2550_resume(struct device *dev)
409{
410 return tsl2550_set_power_state(to_i2c_client(dev), 1);
411}
412
413static SIMPLE_DEV_PM_OPS(tsl2550_pm_ops, tsl2550_suspend, tsl2550_resume);
414#define TSL2550_PM_OPS (&tsl2550_pm_ops)
415
416#else
417
418#define TSL2550_PM_OPS NULL
419
420#endif /* CONFIG_PM_SLEEP */
421
422static const struct i2c_device_id tsl2550_id[] = {
423 { "tsl2550", 0 },
424 { }
425};
426MODULE_DEVICE_TABLE(i2c, tsl2550_id);
427
428static const struct of_device_id tsl2550_of_match[] = {
429 { .compatible = "taos,tsl2550" },
430 { }
431};
432MODULE_DEVICE_TABLE(of, tsl2550_of_match);
433
434static struct i2c_driver tsl2550_driver = {
435 .driver = {
436 .name = TSL2550_DRV_NAME,
437 .of_match_table = tsl2550_of_match,
438 .pm = TSL2550_PM_OPS,
439 },
440 .probe_new = tsl2550_probe,
441 .remove = tsl2550_remove,
442 .id_table = tsl2550_id,
443};
444
445module_i2c_driver(tsl2550_driver);
446
447MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
448MODULE_DESCRIPTION("TSL2550 ambient light sensor driver");
449MODULE_LICENSE("GPL");
450MODULE_VERSION(DRIVER_VERSION);