1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * I2C client/driver for the Linear Technology LTC2941, LTC2942, LTC2943
4 * and LTC2944 Battery Gas Gauge IC
5 *
6 * Copyright (C) 2014 Topic Embedded Systems
7 *
8 * Author: Auryn Verwegen
9 * Author: Mike Looijmans
10 */
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/of_device.h>
14 #include <linux/types.h>
15 #include <linux/errno.h>
16 #include <linux/swab.h>
17 #include <linux/i2c.h>
18 #include <linux/delay.h>
19 #include <linux/power_supply.h>
20 #include <linux/slab.h>
21
22 #define I16_MSB(x) ((x >> 8) & 0xFF)
23 #define I16_LSB(x) (x & 0xFF)
24
25 #define LTC294X_WORK_DELAY 10 /* Update delay in seconds */
26
27 #define LTC294X_MAX_VALUE 0xFFFF
28 #define LTC294X_MID_SUPPLY 0x7FFF
29
30 #define LTC2941_MAX_PRESCALER_EXP 7
31 #define LTC2943_MAX_PRESCALER_EXP 6
32
33 enum ltc294x_reg {
34 LTC294X_REG_STATUS = 0x00,
35 LTC294X_REG_CONTROL = 0x01,
36 LTC294X_REG_ACC_CHARGE_MSB = 0x02,
37 LTC294X_REG_ACC_CHARGE_LSB = 0x03,
38 LTC294X_REG_CHARGE_THR_HIGH_MSB = 0x04,
39 LTC294X_REG_CHARGE_THR_HIGH_LSB = 0x05,
40 LTC294X_REG_CHARGE_THR_LOW_MSB = 0x06,
41 LTC294X_REG_CHARGE_THR_LOW_LSB = 0x07,
42 LTC294X_REG_VOLTAGE_MSB = 0x08,
43 LTC294X_REG_VOLTAGE_LSB = 0x09,
44 LTC2942_REG_TEMPERATURE_MSB = 0x0C,
45 LTC2942_REG_TEMPERATURE_LSB = 0x0D,
46 LTC2943_REG_CURRENT_MSB = 0x0E,
47 LTC2943_REG_CURRENT_LSB = 0x0F,
48 LTC2943_REG_TEMPERATURE_MSB = 0x14,
49 LTC2943_REG_TEMPERATURE_LSB = 0x15,
50 };
51
52 enum ltc294x_id {
53 LTC2941_ID,
54 LTC2942_ID,
55 LTC2943_ID,
56 LTC2944_ID,
57 };
58
59 #define LTC2941_REG_STATUS_CHIP_ID BIT(7)
60
61 #define LTC2942_REG_CONTROL_MODE_SCAN (BIT(7) | BIT(6))
62 #define LTC2943_REG_CONTROL_MODE_SCAN BIT(7)
63 #define LTC294X_REG_CONTROL_PRESCALER_MASK (BIT(5) | BIT(4) | BIT(3))
64 #define LTC294X_REG_CONTROL_SHUTDOWN_MASK (BIT(0))
65 #define LTC294X_REG_CONTROL_PRESCALER_SET(x) \
66 ((x << 3) & LTC294X_REG_CONTROL_PRESCALER_MASK)
67 #define LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED 0
68 #define LTC294X_REG_CONTROL_ADC_DISABLE(x) ((x) & ~(BIT(7) | BIT(6)))
69
70 struct ltc294x_info {
71 struct i2c_client *client; /* I2C Client pointer */
72 struct power_supply *supply; /* Supply pointer */
73 struct power_supply_desc supply_desc; /* Supply description */
74 struct delayed_work work; /* Work scheduler */
75 enum ltc294x_id id; /* Chip type */
76 int charge; /* Last charge register content */
77 int r_sense; /* mOhm */
78 int Qlsb; /* nAh */
79 };
80
convert_bin_to_uAh(const struct ltc294x_info * info,int Q)81 static inline int convert_bin_to_uAh(
82 const struct ltc294x_info *info, int Q)
83 {
84 return ((Q * (info->Qlsb / 10))) / 100;
85 }
86
convert_uAh_to_bin(const struct ltc294x_info * info,int uAh)87 static inline int convert_uAh_to_bin(
88 const struct ltc294x_info *info, int uAh)
89 {
90 int Q;
91
92 Q = (uAh * 100) / (info->Qlsb/10);
93 return (Q < LTC294X_MAX_VALUE) ? Q : LTC294X_MAX_VALUE;
94 }
95
ltc294x_read_regs(struct i2c_client * client,enum ltc294x_reg reg,u8 * buf,int num_regs)96 static int ltc294x_read_regs(struct i2c_client *client,
97 enum ltc294x_reg reg, u8 *buf, int num_regs)
98 {
99 int ret;
100 struct i2c_msg msgs[2] = { };
101 u8 reg_start = reg;
102
103 msgs[0].addr = client->addr;
104 msgs[0].len = 1;
105 msgs[0].buf = ®_start;
106
107 msgs[1].addr = client->addr;
108 msgs[1].len = num_regs;
109 msgs[1].buf = buf;
110 msgs[1].flags = I2C_M_RD;
111
112 ret = i2c_transfer(client->adapter, &msgs[0], 2);
113 if (ret < 0) {
114 dev_err(&client->dev, "ltc2941 read_reg failed!\n");
115 return ret;
116 }
117
118 dev_dbg(&client->dev, "%s (%#x, %d) -> %#x\n",
119 __func__, reg, num_regs, *buf);
120
121 return 0;
122 }
123
ltc294x_write_regs(struct i2c_client * client,enum ltc294x_reg reg,const u8 * buf,int num_regs)124 static int ltc294x_write_regs(struct i2c_client *client,
125 enum ltc294x_reg reg, const u8 *buf, int num_regs)
126 {
127 int ret;
128 u8 reg_start = reg;
129
130 ret = i2c_smbus_write_i2c_block_data(client, reg_start, num_regs, buf);
131 if (ret < 0) {
132 dev_err(&client->dev, "ltc2941 write_reg failed!\n");
133 return ret;
134 }
135
136 dev_dbg(&client->dev, "%s (%#x, %d) -> %#x\n",
137 __func__, reg, num_regs, *buf);
138
139 return 0;
140 }
141
ltc294x_reset(const struct ltc294x_info * info,int prescaler_exp)142 static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp)
143 {
144 int ret;
145 u8 value;
146 u8 control;
147
148 /* Read status and control registers */
149 ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value, 1);
150 if (ret < 0) {
151 dev_err(&info->client->dev,
152 "Could not read registers from device\n");
153 goto error_exit;
154 }
155
156 control = LTC294X_REG_CONTROL_PRESCALER_SET(prescaler_exp) |
157 LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED;
158 /* Put device into "monitor" mode */
159 switch (info->id) {
160 case LTC2942_ID: /* 2942 measures every 2 sec */
161 control |= LTC2942_REG_CONTROL_MODE_SCAN;
162 break;
163 case LTC2943_ID:
164 case LTC2944_ID: /* 2943 and 2944 measure every 10 sec */
165 control |= LTC2943_REG_CONTROL_MODE_SCAN;
166 break;
167 default:
168 break;
169 }
170
171 if (value != control) {
172 ret = ltc294x_write_regs(info->client,
173 LTC294X_REG_CONTROL, &control, 1);
174 if (ret < 0) {
175 dev_err(&info->client->dev,
176 "Could not write register\n");
177 goto error_exit;
178 }
179 }
180
181 return 0;
182
183 error_exit:
184 return ret;
185 }
186
ltc294x_read_charge_register(const struct ltc294x_info * info,enum ltc294x_reg reg)187 static int ltc294x_read_charge_register(const struct ltc294x_info *info,
188 enum ltc294x_reg reg)
189 {
190 int ret;
191 u8 datar[2];
192
193 ret = ltc294x_read_regs(info->client, reg, &datar[0], 2);
194 if (ret < 0)
195 return ret;
196 return (datar[0] << 8) + datar[1];
197 }
198
ltc294x_get_charge(const struct ltc294x_info * info,enum ltc294x_reg reg,int * val)199 static int ltc294x_get_charge(const struct ltc294x_info *info,
200 enum ltc294x_reg reg, int *val)
201 {
202 int value = ltc294x_read_charge_register(info, reg);
203
204 if (value < 0)
205 return value;
206 /* When r_sense < 0, this counts up when the battery discharges */
207 if (info->Qlsb < 0)
208 value -= 0xFFFF;
209 *val = convert_bin_to_uAh(info, value);
210 return 0;
211 }
212
ltc294x_set_charge_now(const struct ltc294x_info * info,int val)213 static int ltc294x_set_charge_now(const struct ltc294x_info *info, int val)
214 {
215 int ret;
216 u8 dataw[2];
217 u8 ctrl_reg;
218 s32 value;
219
220 value = convert_uAh_to_bin(info, val);
221 /* Direction depends on how sense+/- were connected */
222 if (info->Qlsb < 0)
223 value += 0xFFFF;
224 if ((value < 0) || (value > 0xFFFF)) /* input validation */
225 return -EINVAL;
226
227 /* Read control register */
228 ret = ltc294x_read_regs(info->client,
229 LTC294X_REG_CONTROL, &ctrl_reg, 1);
230 if (ret < 0)
231 return ret;
232 /* Disable analog section */
233 ctrl_reg |= LTC294X_REG_CONTROL_SHUTDOWN_MASK;
234 ret = ltc294x_write_regs(info->client,
235 LTC294X_REG_CONTROL, &ctrl_reg, 1);
236 if (ret < 0)
237 return ret;
238 /* Set new charge value */
239 dataw[0] = I16_MSB(value);
240 dataw[1] = I16_LSB(value);
241 ret = ltc294x_write_regs(info->client,
242 LTC294X_REG_ACC_CHARGE_MSB, &dataw[0], 2);
243 if (ret < 0)
244 goto error_exit;
245 /* Enable analog section */
246 error_exit:
247 ctrl_reg &= ~LTC294X_REG_CONTROL_SHUTDOWN_MASK;
248 ret = ltc294x_write_regs(info->client,
249 LTC294X_REG_CONTROL, &ctrl_reg, 1);
250
251 return ret < 0 ? ret : 0;
252 }
253
ltc294x_set_charge_thr(const struct ltc294x_info * info,enum ltc294x_reg reg,int val)254 static int ltc294x_set_charge_thr(const struct ltc294x_info *info,
255 enum ltc294x_reg reg, int val)
256 {
257 u8 dataw[2];
258 s32 value;
259
260 value = convert_uAh_to_bin(info, val);
261 /* Direction depends on how sense+/- were connected */
262 if (info->Qlsb < 0)
263 value += 0xFFFF;
264 if ((value < 0) || (value > 0xFFFF)) /* input validation */
265 return -EINVAL;
266
267 /* Set new charge value */
268 dataw[0] = I16_MSB(value);
269 dataw[1] = I16_LSB(value);
270 return ltc294x_write_regs(info->client, reg, &dataw[0], 2);
271 }
272
ltc294x_get_charge_counter(const struct ltc294x_info * info,int * val)273 static int ltc294x_get_charge_counter(
274 const struct ltc294x_info *info, int *val)
275 {
276 int value = ltc294x_read_charge_register(info, LTC294X_REG_ACC_CHARGE_MSB);
277
278 if (value < 0)
279 return value;
280 value -= LTC294X_MID_SUPPLY;
281 *val = convert_bin_to_uAh(info, value);
282 return 0;
283 }
284
ltc294x_get_voltage(const struct ltc294x_info * info,int * val)285 static int ltc294x_get_voltage(const struct ltc294x_info *info, int *val)
286 {
287 int ret;
288 u8 datar[2];
289 u32 value;
290
291 ret = ltc294x_read_regs(info->client,
292 LTC294X_REG_VOLTAGE_MSB, &datar[0], 2);
293 value = (datar[0] << 8) | datar[1];
294 switch (info->id) {
295 case LTC2943_ID:
296 value *= 23600 * 2;
297 value /= 0xFFFF;
298 value *= 1000 / 2;
299 break;
300 case LTC2944_ID:
301 value *= 70800 / 5*4;
302 value /= 0xFFFF;
303 value *= 1000 * 5/4;
304 break;
305 default:
306 value *= 6000 * 10;
307 value /= 0xFFFF;
308 value *= 1000 / 10;
309 break;
310 }
311 *val = value;
312 return ret;
313 }
314
ltc294x_get_current(const struct ltc294x_info * info,int * val)315 static int ltc294x_get_current(const struct ltc294x_info *info, int *val)
316 {
317 int ret;
318 u8 datar[2];
319 s32 value;
320
321 ret = ltc294x_read_regs(info->client,
322 LTC2943_REG_CURRENT_MSB, &datar[0], 2);
323 value = (datar[0] << 8) | datar[1];
324 value -= 0x7FFF;
325 if (info->id == LTC2944_ID)
326 value *= 64000;
327 else
328 value *= 60000;
329 /* Value is in range -32k..+32k, r_sense is usually 10..50 mOhm,
330 * the formula below keeps everything in s32 range while preserving
331 * enough digits */
332 *val = 1000 * (value / (info->r_sense * 0x7FFF)); /* in uA */
333 return ret;
334 }
335
ltc294x_get_temperature(const struct ltc294x_info * info,int * val)336 static int ltc294x_get_temperature(const struct ltc294x_info *info, int *val)
337 {
338 enum ltc294x_reg reg;
339 int ret;
340 u8 datar[2];
341 u32 value;
342
343 if (info->id == LTC2942_ID) {
344 reg = LTC2942_REG_TEMPERATURE_MSB;
345 value = 6000; /* Full-scale is 600 Kelvin */
346 } else {
347 reg = LTC2943_REG_TEMPERATURE_MSB;
348 value = 5100; /* Full-scale is 510 Kelvin */
349 }
350 ret = ltc294x_read_regs(info->client, reg, &datar[0], 2);
351 value *= (datar[0] << 8) | datar[1];
352 /* Convert to tenths of degree Celsius */
353 *val = value / 0xFFFF - 2722;
354 return ret;
355 }
356
ltc294x_get_property(struct power_supply * psy,enum power_supply_property prop,union power_supply_propval * val)357 static int ltc294x_get_property(struct power_supply *psy,
358 enum power_supply_property prop,
359 union power_supply_propval *val)
360 {
361 struct ltc294x_info *info = power_supply_get_drvdata(psy);
362
363 switch (prop) {
364 case POWER_SUPPLY_PROP_CHARGE_FULL:
365 return ltc294x_get_charge(info, LTC294X_REG_CHARGE_THR_HIGH_MSB,
366 &val->intval);
367 case POWER_SUPPLY_PROP_CHARGE_EMPTY:
368 return ltc294x_get_charge(info, LTC294X_REG_CHARGE_THR_LOW_MSB,
369 &val->intval);
370 case POWER_SUPPLY_PROP_CHARGE_NOW:
371 return ltc294x_get_charge(info, LTC294X_REG_ACC_CHARGE_MSB,
372 &val->intval);
373 case POWER_SUPPLY_PROP_CHARGE_COUNTER:
374 return ltc294x_get_charge_counter(info, &val->intval);
375 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
376 return ltc294x_get_voltage(info, &val->intval);
377 case POWER_SUPPLY_PROP_CURRENT_NOW:
378 return ltc294x_get_current(info, &val->intval);
379 case POWER_SUPPLY_PROP_TEMP:
380 return ltc294x_get_temperature(info, &val->intval);
381 default:
382 return -EINVAL;
383 }
384 }
385
ltc294x_set_property(struct power_supply * psy,enum power_supply_property psp,const union power_supply_propval * val)386 static int ltc294x_set_property(struct power_supply *psy,
387 enum power_supply_property psp,
388 const union power_supply_propval *val)
389 {
390 struct ltc294x_info *info = power_supply_get_drvdata(psy);
391
392 switch (psp) {
393 case POWER_SUPPLY_PROP_CHARGE_FULL:
394 return ltc294x_set_charge_thr(info,
395 LTC294X_REG_CHARGE_THR_HIGH_MSB, val->intval);
396 case POWER_SUPPLY_PROP_CHARGE_EMPTY:
397 return ltc294x_set_charge_thr(info,
398 LTC294X_REG_CHARGE_THR_LOW_MSB, val->intval);
399 case POWER_SUPPLY_PROP_CHARGE_NOW:
400 return ltc294x_set_charge_now(info, val->intval);
401 default:
402 return -EPERM;
403 }
404 }
405
ltc294x_property_is_writeable(struct power_supply * psy,enum power_supply_property psp)406 static int ltc294x_property_is_writeable(
407 struct power_supply *psy, enum power_supply_property psp)
408 {
409 switch (psp) {
410 case POWER_SUPPLY_PROP_CHARGE_FULL:
411 case POWER_SUPPLY_PROP_CHARGE_EMPTY:
412 case POWER_SUPPLY_PROP_CHARGE_NOW:
413 return 1;
414 default:
415 return 0;
416 }
417 }
418
ltc294x_update(struct ltc294x_info * info)419 static void ltc294x_update(struct ltc294x_info *info)
420 {
421 int charge = ltc294x_read_charge_register(info, LTC294X_REG_ACC_CHARGE_MSB);
422
423 if (charge != info->charge) {
424 info->charge = charge;
425 power_supply_changed(info->supply);
426 }
427 }
428
ltc294x_work(struct work_struct * work)429 static void ltc294x_work(struct work_struct *work)
430 {
431 struct ltc294x_info *info;
432
433 info = container_of(work, struct ltc294x_info, work.work);
434 ltc294x_update(info);
435 schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
436 }
437
438 static enum power_supply_property ltc294x_properties[] = {
439 POWER_SUPPLY_PROP_CHARGE_COUNTER,
440 POWER_SUPPLY_PROP_CHARGE_FULL,
441 POWER_SUPPLY_PROP_CHARGE_EMPTY,
442 POWER_SUPPLY_PROP_CHARGE_NOW,
443 POWER_SUPPLY_PROP_VOLTAGE_NOW,
444 POWER_SUPPLY_PROP_TEMP,
445 POWER_SUPPLY_PROP_CURRENT_NOW,
446 };
447
ltc294x_i2c_remove(struct i2c_client * client)448 static int ltc294x_i2c_remove(struct i2c_client *client)
449 {
450 struct ltc294x_info *info = i2c_get_clientdata(client);
451
452 cancel_delayed_work_sync(&info->work);
453 power_supply_unregister(info->supply);
454 return 0;
455 }
456
ltc294x_i2c_probe(struct i2c_client * client,const struct i2c_device_id * id)457 static int ltc294x_i2c_probe(struct i2c_client *client,
458 const struct i2c_device_id *id)
459 {
460 struct power_supply_config psy_cfg = {};
461 struct ltc294x_info *info;
462 struct device_node *np;
463 int ret;
464 u32 prescaler_exp;
465 s32 r_sense;
466 u8 status;
467
468 info = devm_kzalloc(&client->dev, sizeof(*info), GFP_KERNEL);
469 if (info == NULL)
470 return -ENOMEM;
471
472 i2c_set_clientdata(client, info);
473
474 np = of_node_get(client->dev.of_node);
475
476 info->id = (enum ltc294x_id) (uintptr_t) of_device_get_match_data(
477 &client->dev);
478 info->supply_desc.name = np->name;
479
480 /* r_sense can be negative, when sense+ is connected to the battery
481 * instead of the sense-. This results in reversed measurements. */
482 ret = of_property_read_u32(np, "lltc,resistor-sense", &r_sense);
483 if (ret < 0) {
484 dev_err(&client->dev,
485 "Could not find lltc,resistor-sense in devicetree\n");
486 return ret;
487 }
488 info->r_sense = r_sense;
489
490 ret = of_property_read_u32(np, "lltc,prescaler-exponent",
491 &prescaler_exp);
492 if (ret < 0) {
493 dev_warn(&client->dev,
494 "lltc,prescaler-exponent not in devicetree\n");
495 prescaler_exp = LTC2941_MAX_PRESCALER_EXP;
496 }
497
498 if (info->id == LTC2943_ID) {
499 if (prescaler_exp > LTC2943_MAX_PRESCALER_EXP)
500 prescaler_exp = LTC2943_MAX_PRESCALER_EXP;
501 info->Qlsb = ((340 * 50000) / r_sense) /
502 (4096 / (1 << (2*prescaler_exp)));
503 } else {
504 if (prescaler_exp > LTC2941_MAX_PRESCALER_EXP)
505 prescaler_exp = LTC2941_MAX_PRESCALER_EXP;
506 info->Qlsb = ((85 * 50000) / r_sense) /
507 (128 / (1 << prescaler_exp));
508 }
509
510 /* Read status register to check for LTC2942 */
511 if (info->id == LTC2941_ID || info->id == LTC2942_ID) {
512 ret = ltc294x_read_regs(client, LTC294X_REG_STATUS, &status, 1);
513 if (ret < 0) {
514 dev_err(&client->dev,
515 "Could not read status register\n");
516 return ret;
517 }
518 if (status & LTC2941_REG_STATUS_CHIP_ID)
519 info->id = LTC2941_ID;
520 else
521 info->id = LTC2942_ID;
522 }
523
524 info->client = client;
525 info->supply_desc.type = POWER_SUPPLY_TYPE_BATTERY;
526 info->supply_desc.properties = ltc294x_properties;
527 switch (info->id) {
528 case LTC2944_ID:
529 case LTC2943_ID:
530 info->supply_desc.num_properties =
531 ARRAY_SIZE(ltc294x_properties);
532 break;
533 case LTC2942_ID:
534 info->supply_desc.num_properties =
535 ARRAY_SIZE(ltc294x_properties) - 1;
536 break;
537 case LTC2941_ID:
538 default:
539 info->supply_desc.num_properties =
540 ARRAY_SIZE(ltc294x_properties) - 3;
541 break;
542 }
543 info->supply_desc.get_property = ltc294x_get_property;
544 info->supply_desc.set_property = ltc294x_set_property;
545 info->supply_desc.property_is_writeable = ltc294x_property_is_writeable;
546 info->supply_desc.external_power_changed = NULL;
547
548 psy_cfg.drv_data = info;
549
550 INIT_DELAYED_WORK(&info->work, ltc294x_work);
551
552 ret = ltc294x_reset(info, prescaler_exp);
553 if (ret < 0) {
554 dev_err(&client->dev, "Communication with chip failed\n");
555 return ret;
556 }
557
558 info->supply = power_supply_register(&client->dev, &info->supply_desc,
559 &psy_cfg);
560 if (IS_ERR(info->supply)) {
561 dev_err(&client->dev, "failed to register ltc2941\n");
562 return PTR_ERR(info->supply);
563 } else {
564 schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
565 }
566
567 return 0;
568 }
569
ltc294x_i2c_shutdown(struct i2c_client * client)570 static void ltc294x_i2c_shutdown(struct i2c_client *client)
571 {
572 struct ltc294x_info *info = i2c_get_clientdata(client);
573 int ret;
574 u8 value;
575 u8 control;
576
577 /* The LTC2941 does not need any special handling */
578 if (info->id == LTC2941_ID)
579 return;
580
581 /* Read control register */
582 ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value, 1);
583 if (ret < 0)
584 return;
585
586 /* Disable continuous ADC conversion as this drains the battery */
587 control = LTC294X_REG_CONTROL_ADC_DISABLE(value);
588 if (control != value)
589 ltc294x_write_regs(info->client, LTC294X_REG_CONTROL,
590 &control, 1);
591 }
592
593 #ifdef CONFIG_PM_SLEEP
594
ltc294x_suspend(struct device * dev)595 static int ltc294x_suspend(struct device *dev)
596 {
597 struct i2c_client *client = to_i2c_client(dev);
598 struct ltc294x_info *info = i2c_get_clientdata(client);
599
600 cancel_delayed_work(&info->work);
601 return 0;
602 }
603
ltc294x_resume(struct device * dev)604 static int ltc294x_resume(struct device *dev)
605 {
606 struct i2c_client *client = to_i2c_client(dev);
607 struct ltc294x_info *info = i2c_get_clientdata(client);
608
609 schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
610 return 0;
611 }
612
613 static SIMPLE_DEV_PM_OPS(ltc294x_pm_ops, ltc294x_suspend, ltc294x_resume);
614 #define LTC294X_PM_OPS (<c294x_pm_ops)
615
616 #else
617 #define LTC294X_PM_OPS NULL
618 #endif /* CONFIG_PM_SLEEP */
619
620
621 static const struct i2c_device_id ltc294x_i2c_id[] = {
622 { "ltc2941", LTC2941_ID, },
623 { "ltc2942", LTC2942_ID, },
624 { "ltc2943", LTC2943_ID, },
625 { "ltc2944", LTC2944_ID, },
626 { },
627 };
628 MODULE_DEVICE_TABLE(i2c, ltc294x_i2c_id);
629
630 static const struct of_device_id ltc294x_i2c_of_match[] = {
631 {
632 .compatible = "lltc,ltc2941",
633 .data = (void *)LTC2941_ID,
634 },
635 {
636 .compatible = "lltc,ltc2942",
637 .data = (void *)LTC2942_ID,
638 },
639 {
640 .compatible = "lltc,ltc2943",
641 .data = (void *)LTC2943_ID,
642 },
643 {
644 .compatible = "lltc,ltc2944",
645 .data = (void *)LTC2944_ID,
646 },
647 { },
648 };
649 MODULE_DEVICE_TABLE(of, ltc294x_i2c_of_match);
650
651 static struct i2c_driver ltc294x_driver = {
652 .driver = {
653 .name = "LTC2941",
654 .of_match_table = ltc294x_i2c_of_match,
655 .pm = LTC294X_PM_OPS,
656 },
657 .probe = ltc294x_i2c_probe,
658 .remove = ltc294x_i2c_remove,
659 .shutdown = ltc294x_i2c_shutdown,
660 .id_table = ltc294x_i2c_id,
661 };
662 module_i2c_driver(ltc294x_driver);
663
664 MODULE_AUTHOR("Auryn Verwegen, Topic Embedded Systems");
665 MODULE_AUTHOR("Mike Looijmans, Topic Embedded Products");
666 MODULE_DESCRIPTION("LTC2941/LTC2942/LTC2943/LTC2944 Battery Gas Gauge IC driver");
667 MODULE_LICENSE("GPL");
668
