1 // SPDX-License-Identifier: GPL-2.0
3 * Fuel gauge driver for CellWise 2013 / 2015
5 * Copyright (C) 2012, RockChip
6 * Copyright (C) 2020, Tobias Schramm
8 * Authors: xuhuicong <xhc@rock-chips.com>
9 * Authors: Tobias Schramm <t.schramm@manjaro.org>
12 #include <linux/bits.h>
13 #include <linux/delay.h>
14 #include <linux/i2c.h>
15 #include <linux/gfp.h>
16 #include <linux/gpio/consumer.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/power_supply.h>
20 #include <linux/property.h>
21 #include <linux/regmap.h>
22 #include <linux/time.h>
23 #include <linux/workqueue.h>
24 #include <linux/devm-helpers.h>
26 #define CW2015_SIZE_BATINFO 64
28 #define CW2015_RESET_TRIES 5
30 #define CW2015_REG_VERSION 0x00
31 #define CW2015_REG_VCELL 0x02
32 #define CW2015_REG_SOC 0x04
33 #define CW2015_REG_RRT_ALERT 0x06
34 #define CW2015_REG_CONFIG 0x08
35 #define CW2015_REG_MODE 0x0A
36 #define CW2015_REG_BATINFO 0x10
38 #define CW2015_MODE_SLEEP_MASK GENMASK(7, 6)
39 #define CW2015_MODE_SLEEP (0x03 << 6)
40 #define CW2015_MODE_NORMAL (0x00 << 6)
41 #define CW2015_MODE_QUICK_START (0x03 << 4)
42 #define CW2015_MODE_RESTART (0x0f << 0)
44 #define CW2015_CONFIG_UPDATE_FLG (0x01 << 1)
45 #define CW2015_ATHD(x) ((x) << 3)
46 #define CW2015_MASK_ATHD GENMASK(7, 3)
47 #define CW2015_MASK_SOC GENMASK(12, 0)
49 /* reset gauge of no valid state of charge could be polled for 40s */
50 #define CW2015_BAT_SOC_ERROR_MS (40 * MSEC_PER_SEC)
51 /* reset gauge if state of charge stuck for half an hour during charging */
52 #define CW2015_BAT_CHARGING_STUCK_MS (1800 * MSEC_PER_SEC)
54 /* poll interval from CellWise GPL Android driver example */
55 #define CW2015_DEFAULT_POLL_INTERVAL_MS 8000
57 #define CW2015_AVERAGING_SAMPLES 3
61 struct workqueue_struct *battery_workqueue;
62 struct delayed_work battery_delay_work;
63 struct regmap *regmap;
64 struct power_supply *rk_bat;
65 struct power_supply_battery_info *battery;
68 bool charger_attached;
80 unsigned int read_errors;
81 unsigned int charge_stuck_cnt;
84 static int cw_read_word(struct cw_battery *cw_bat, u8 reg, u16 *val)
89 ret = regmap_bulk_read(cw_bat->regmap, reg, &value, sizeof(value));
93 *val = be16_to_cpu(value);
97 static int cw_update_profile(struct cw_battery *cw_bat)
100 unsigned int reg_val;
103 /* make sure gauge is not in sleep mode */
104 ret = regmap_read(cw_bat->regmap, CW2015_REG_MODE, ®_val);
109 if ((reg_val & CW2015_MODE_SLEEP_MASK) == CW2015_MODE_SLEEP) {
111 "Gauge is in sleep mode, can't update battery info\n");
115 /* write new battery info */
116 ret = regmap_raw_write(cw_bat->regmap, CW2015_REG_BATINFO,
118 CW2015_SIZE_BATINFO);
122 /* set config update flag */
123 reg_val |= CW2015_CONFIG_UPDATE_FLG;
124 reg_val &= ~CW2015_MASK_ATHD;
125 reg_val |= CW2015_ATHD(cw_bat->alert_level);
126 ret = regmap_write(cw_bat->regmap, CW2015_REG_CONFIG, reg_val);
130 /* reset gauge to apply new battery profile */
131 reset_val &= ~CW2015_MODE_RESTART;
132 reg_val = reset_val | CW2015_MODE_RESTART;
133 ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reg_val);
137 /* wait for gauge to reset */
140 /* clear reset flag */
141 ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reset_val);
145 /* wait for gauge to become ready */
146 ret = regmap_read_poll_timeout(cw_bat->regmap, CW2015_REG_SOC,
147 reg_val, reg_val <= 100,
148 10 * USEC_PER_MSEC, 10 * USEC_PER_SEC);
151 "Gauge did not become ready after profile upload\n");
153 dev_dbg(cw_bat->dev, "Battery profile updated\n");
158 static int cw_init(struct cw_battery *cw_bat)
161 unsigned int reg_val = CW2015_MODE_SLEEP;
163 if ((reg_val & CW2015_MODE_SLEEP_MASK) == CW2015_MODE_SLEEP) {
164 reg_val = CW2015_MODE_NORMAL;
165 ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reg_val);
170 ret = regmap_read(cw_bat->regmap, CW2015_REG_CONFIG, ®_val);
174 if ((reg_val & CW2015_MASK_ATHD) != CW2015_ATHD(cw_bat->alert_level)) {
175 dev_dbg(cw_bat->dev, "Setting new alert level\n");
176 reg_val &= ~CW2015_MASK_ATHD;
177 reg_val |= ~CW2015_ATHD(cw_bat->alert_level);
178 ret = regmap_write(cw_bat->regmap, CW2015_REG_CONFIG, reg_val);
183 ret = regmap_read(cw_bat->regmap, CW2015_REG_CONFIG, ®_val);
187 if (!(reg_val & CW2015_CONFIG_UPDATE_FLG)) {
189 "Battery profile not present, uploading battery profile\n");
190 if (cw_bat->bat_profile) {
191 ret = cw_update_profile(cw_bat);
194 "Failed to upload battery profile\n");
198 dev_warn(cw_bat->dev,
199 "No profile specified, continuing without profile\n");
201 } else if (cw_bat->bat_profile) {
202 u8 bat_info[CW2015_SIZE_BATINFO];
204 ret = regmap_raw_read(cw_bat->regmap, CW2015_REG_BATINFO,
205 bat_info, CW2015_SIZE_BATINFO);
208 "Failed to read stored battery profile\n");
212 if (memcmp(bat_info, cw_bat->bat_profile, CW2015_SIZE_BATINFO)) {
213 dev_warn(cw_bat->dev, "Replacing stored battery profile\n");
214 ret = cw_update_profile(cw_bat);
219 dev_warn(cw_bat->dev,
220 "Can't check current battery profile, no profile provided\n");
223 dev_dbg(cw_bat->dev, "Battery profile configured\n");
227 static int cw_power_on_reset(struct cw_battery *cw_bat)
230 unsigned char reset_val;
232 reset_val = CW2015_MODE_SLEEP;
233 ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reset_val);
237 /* wait for gauge to enter sleep */
240 reset_val = CW2015_MODE_NORMAL;
241 ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reset_val);
245 ret = cw_init(cw_bat);
251 #define HYSTERESIS(current, previous, up, down) \
252 (((current) < (previous) + (up)) && ((current) > (previous) - (down)))
254 static int cw_get_soc(struct cw_battery *cw_bat)
259 ret = regmap_read(cw_bat->regmap, CW2015_REG_SOC, &soc);
264 int max_error_cycles =
265 CW2015_BAT_SOC_ERROR_MS / cw_bat->poll_interval_ms;
267 dev_err(cw_bat->dev, "Invalid SoC %d%%\n", soc);
268 cw_bat->read_errors++;
269 if (cw_bat->read_errors > max_error_cycles) {
270 dev_warn(cw_bat->dev,
271 "Too many invalid SoC reports, resetting gauge\n");
272 cw_power_on_reset(cw_bat);
273 cw_bat->read_errors = 0;
277 cw_bat->read_errors = 0;
279 /* Reset gauge if stuck while charging */
280 if (cw_bat->status == POWER_SUPPLY_STATUS_CHARGING && soc == cw_bat->soc) {
281 int max_stuck_cycles =
282 CW2015_BAT_CHARGING_STUCK_MS / cw_bat->poll_interval_ms;
284 cw_bat->charge_stuck_cnt++;
285 if (cw_bat->charge_stuck_cnt > max_stuck_cycles) {
286 dev_warn(cw_bat->dev,
287 "SoC stuck @%u%%, resetting gauge\n", soc);
288 cw_power_on_reset(cw_bat);
289 cw_bat->charge_stuck_cnt = 0;
292 cw_bat->charge_stuck_cnt = 0;
295 /* Ignore voltage dips during charge */
296 if (cw_bat->charger_attached && HYSTERESIS(soc, cw_bat->soc, 0, 3))
299 /* Ignore voltage spikes during discharge */
300 if (!cw_bat->charger_attached && HYSTERESIS(soc, cw_bat->soc, 3, 0))
306 static int cw_get_voltage(struct cw_battery *cw_bat)
308 int ret, i, voltage_mv;
312 for (i = 0; i < CW2015_AVERAGING_SAMPLES; i++) {
313 ret = cw_read_word(cw_bat, CW2015_REG_VCELL, ®_val);
319 avg /= CW2015_AVERAGING_SAMPLES;
322 * 305 uV per ADC step
323 * Use 312 / 1024 as efficient approximation of 305 / 1000
324 * Negligible error of 0.1%
326 voltage_mv = avg * 312 / 1024;
328 dev_dbg(cw_bat->dev, "Read voltage: %d mV, raw=0x%04x\n",
329 voltage_mv, reg_val);
333 static int cw_get_time_to_empty(struct cw_battery *cw_bat)
338 ret = cw_read_word(cw_bat, CW2015_REG_RRT_ALERT, &value16);
342 return value16 & CW2015_MASK_SOC;
345 static void cw_update_charge_status(struct cw_battery *cw_bat)
349 ret = power_supply_am_i_supplied(cw_bat->rk_bat);
351 dev_warn(cw_bat->dev, "Failed to get supply state: %d\n", ret);
353 bool charger_attached;
355 charger_attached = !!ret;
356 if (cw_bat->charger_attached != charger_attached) {
357 cw_bat->battery_changed = true;
358 if (charger_attached)
359 cw_bat->charge_count++;
361 cw_bat->charger_attached = charger_attached;
365 static void cw_update_soc(struct cw_battery *cw_bat)
369 soc = cw_get_soc(cw_bat);
371 dev_err(cw_bat->dev, "Failed to get SoC from gauge: %d\n", soc);
372 else if (cw_bat->soc != soc) {
374 cw_bat->battery_changed = true;
378 static void cw_update_voltage(struct cw_battery *cw_bat)
382 voltage_mv = cw_get_voltage(cw_bat);
384 dev_err(cw_bat->dev, "Failed to get voltage from gauge: %d\n",
387 cw_bat->voltage_mv = voltage_mv;
390 static void cw_update_status(struct cw_battery *cw_bat)
392 int status = POWER_SUPPLY_STATUS_DISCHARGING;
394 if (cw_bat->charger_attached) {
395 if (cw_bat->soc >= 100)
396 status = POWER_SUPPLY_STATUS_FULL;
398 status = POWER_SUPPLY_STATUS_CHARGING;
401 if (cw_bat->status != status)
402 cw_bat->battery_changed = true;
403 cw_bat->status = status;
406 static void cw_update_time_to_empty(struct cw_battery *cw_bat)
410 time_to_empty = cw_get_time_to_empty(cw_bat);
411 if (time_to_empty < 0)
412 dev_err(cw_bat->dev, "Failed to get time to empty from gauge: %d\n",
414 else if (cw_bat->time_to_empty != time_to_empty) {
415 cw_bat->time_to_empty = time_to_empty;
416 cw_bat->battery_changed = true;
420 static void cw_bat_work(struct work_struct *work)
422 struct delayed_work *delay_work;
423 struct cw_battery *cw_bat;
425 unsigned int reg_val;
427 delay_work = to_delayed_work(work);
428 cw_bat = container_of(delay_work, struct cw_battery, battery_delay_work);
429 ret = regmap_read(cw_bat->regmap, CW2015_REG_MODE, ®_val);
431 dev_err(cw_bat->dev, "Failed to read mode from gauge: %d\n", ret);
433 if ((reg_val & CW2015_MODE_SLEEP_MASK) == CW2015_MODE_SLEEP) {
436 for (i = 0; i < CW2015_RESET_TRIES; i++) {
437 if (!cw_power_on_reset(cw_bat))
441 cw_update_soc(cw_bat);
442 cw_update_voltage(cw_bat);
443 cw_update_charge_status(cw_bat);
444 cw_update_status(cw_bat);
445 cw_update_time_to_empty(cw_bat);
447 dev_dbg(cw_bat->dev, "charger_attached = %d\n", cw_bat->charger_attached);
448 dev_dbg(cw_bat->dev, "status = %d\n", cw_bat->status);
449 dev_dbg(cw_bat->dev, "soc = %d%%\n", cw_bat->soc);
450 dev_dbg(cw_bat->dev, "voltage = %dmV\n", cw_bat->voltage_mv);
452 if (cw_bat->battery_changed)
453 power_supply_changed(cw_bat->rk_bat);
454 cw_bat->battery_changed = false;
456 queue_delayed_work(cw_bat->battery_workqueue,
457 &cw_bat->battery_delay_work,
458 msecs_to_jiffies(cw_bat->poll_interval_ms));
461 static bool cw_battery_valid_time_to_empty(struct cw_battery *cw_bat)
463 return cw_bat->time_to_empty > 0 &&
464 cw_bat->time_to_empty < CW2015_MASK_SOC &&
465 cw_bat->status == POWER_SUPPLY_STATUS_DISCHARGING;
468 static int cw_battery_get_property(struct power_supply *psy,
469 enum power_supply_property psp,
470 union power_supply_propval *val)
472 struct cw_battery *cw_bat;
474 cw_bat = power_supply_get_drvdata(psy);
476 case POWER_SUPPLY_PROP_CAPACITY:
477 val->intval = cw_bat->soc;
480 case POWER_SUPPLY_PROP_STATUS:
481 val->intval = cw_bat->status;
484 case POWER_SUPPLY_PROP_PRESENT:
485 val->intval = !!cw_bat->voltage_mv;
488 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
489 val->intval = cw_bat->voltage_mv * 1000;
492 case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
493 if (cw_battery_valid_time_to_empty(cw_bat))
494 val->intval = cw_bat->time_to_empty;
499 case POWER_SUPPLY_PROP_TECHNOLOGY:
500 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
503 case POWER_SUPPLY_PROP_CHARGE_COUNTER:
504 val->intval = cw_bat->charge_count;
507 case POWER_SUPPLY_PROP_CHARGE_FULL:
508 case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
509 if (cw_bat->battery->charge_full_design_uah > 0)
510 val->intval = cw_bat->battery->charge_full_design_uah;
515 case POWER_SUPPLY_PROP_CHARGE_NOW:
516 val->intval = cw_bat->battery->charge_full_design_uah;
517 val->intval = val->intval * cw_bat->soc / 100;
520 case POWER_SUPPLY_PROP_CURRENT_NOW:
521 if (cw_battery_valid_time_to_empty(cw_bat) &&
522 cw_bat->battery->charge_full_design_uah > 0) {
523 /* calculate remaining capacity */
524 val->intval = cw_bat->battery->charge_full_design_uah;
525 val->intval = val->intval * cw_bat->soc / 100;
527 /* estimate current based on time to empty */
528 val->intval = 60 * val->intval / cw_bat->time_to_empty;
541 static enum power_supply_property cw_battery_properties[] = {
542 POWER_SUPPLY_PROP_CAPACITY,
543 POWER_SUPPLY_PROP_STATUS,
544 POWER_SUPPLY_PROP_PRESENT,
545 POWER_SUPPLY_PROP_VOLTAGE_NOW,
546 POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
547 POWER_SUPPLY_PROP_TECHNOLOGY,
548 POWER_SUPPLY_PROP_CHARGE_COUNTER,
549 POWER_SUPPLY_PROP_CHARGE_FULL,
550 POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
551 POWER_SUPPLY_PROP_CHARGE_NOW,
552 POWER_SUPPLY_PROP_CURRENT_NOW,
555 static const struct power_supply_desc cw2015_bat_desc = {
556 .name = "cw2015-battery",
557 .type = POWER_SUPPLY_TYPE_BATTERY,
558 .properties = cw_battery_properties,
559 .num_properties = ARRAY_SIZE(cw_battery_properties),
560 .get_property = cw_battery_get_property,
563 static int cw2015_parse_properties(struct cw_battery *cw_bat)
565 struct device *dev = cw_bat->dev;
569 length = device_property_count_u8(dev, "cellwise,battery-profile");
571 dev_warn(cw_bat->dev,
572 "No battery-profile found, using current flash contents\n");
573 } else if (length != CW2015_SIZE_BATINFO) {
574 dev_err(cw_bat->dev, "battery-profile must be %d bytes\n",
575 CW2015_SIZE_BATINFO);
578 cw_bat->bat_profile = devm_kzalloc(dev, length, GFP_KERNEL);
579 if (!cw_bat->bat_profile)
582 ret = device_property_read_u8_array(dev,
583 "cellwise,battery-profile",
590 ret = device_property_read_u32(dev, "cellwise,monitor-interval-ms",
591 &cw_bat->poll_interval_ms);
593 dev_dbg(cw_bat->dev, "Using default poll interval\n");
594 cw_bat->poll_interval_ms = CW2015_DEFAULT_POLL_INTERVAL_MS;
600 static const struct regmap_range regmap_ranges_rd_yes[] = {
601 regmap_reg_range(CW2015_REG_VERSION, CW2015_REG_VERSION),
602 regmap_reg_range(CW2015_REG_VCELL, CW2015_REG_CONFIG),
603 regmap_reg_range(CW2015_REG_MODE, CW2015_REG_MODE),
604 regmap_reg_range(CW2015_REG_BATINFO,
605 CW2015_REG_BATINFO + CW2015_SIZE_BATINFO - 1),
608 static const struct regmap_access_table regmap_rd_table = {
609 .yes_ranges = regmap_ranges_rd_yes,
613 static const struct regmap_range regmap_ranges_wr_yes[] = {
614 regmap_reg_range(CW2015_REG_RRT_ALERT, CW2015_REG_CONFIG),
615 regmap_reg_range(CW2015_REG_MODE, CW2015_REG_MODE),
616 regmap_reg_range(CW2015_REG_BATINFO,
617 CW2015_REG_BATINFO + CW2015_SIZE_BATINFO - 1),
620 static const struct regmap_access_table regmap_wr_table = {
621 .yes_ranges = regmap_ranges_wr_yes,
625 static const struct regmap_range regmap_ranges_vol_yes[] = {
626 regmap_reg_range(CW2015_REG_VCELL, CW2015_REG_SOC + 1),
629 static const struct regmap_access_table regmap_vol_table = {
630 .yes_ranges = regmap_ranges_vol_yes,
634 static const struct regmap_config cw2015_regmap_config = {
637 .rd_table = ®map_rd_table,
638 .wr_table = ®map_wr_table,
639 .volatile_table = ®map_vol_table,
640 .max_register = CW2015_REG_BATINFO + CW2015_SIZE_BATINFO - 1,
643 static int cw_bat_probe(struct i2c_client *client)
646 struct cw_battery *cw_bat;
647 struct power_supply_config psy_cfg = { 0 };
649 cw_bat = devm_kzalloc(&client->dev, sizeof(*cw_bat), GFP_KERNEL);
653 i2c_set_clientdata(client, cw_bat);
654 cw_bat->dev = &client->dev;
657 ret = cw2015_parse_properties(cw_bat);
659 dev_err(cw_bat->dev, "Failed to parse cw2015 properties\n");
663 cw_bat->regmap = devm_regmap_init_i2c(client, &cw2015_regmap_config);
664 if (IS_ERR(cw_bat->regmap)) {
665 dev_err(cw_bat->dev, "Failed to allocate regmap: %ld\n",
666 PTR_ERR(cw_bat->regmap));
667 return PTR_ERR(cw_bat->regmap);
670 ret = cw_init(cw_bat);
672 dev_err(cw_bat->dev, "Init failed: %d\n", ret);
676 psy_cfg.drv_data = cw_bat;
677 psy_cfg.fwnode = dev_fwnode(cw_bat->dev);
679 cw_bat->rk_bat = devm_power_supply_register(&client->dev,
682 if (IS_ERR(cw_bat->rk_bat)) {
683 /* try again if this happens */
684 dev_err_probe(&client->dev, PTR_ERR(cw_bat->rk_bat),
685 "Failed to register power supply\n");
686 return PTR_ERR(cw_bat->rk_bat);
689 ret = power_supply_get_battery_info(cw_bat->rk_bat, &cw_bat->battery);
691 /* Allocate an empty battery */
692 cw_bat->battery = devm_kzalloc(&client->dev,
693 sizeof(*cw_bat->battery),
695 if (!cw_bat->battery)
697 dev_warn(cw_bat->dev,
698 "No monitored battery, some properties will be missing\n");
701 cw_bat->battery_workqueue = create_singlethread_workqueue("rk_battery");
702 if (!cw_bat->battery_workqueue)
705 devm_delayed_work_autocancel(&client->dev,
706 &cw_bat->battery_delay_work, cw_bat_work);
707 queue_delayed_work(cw_bat->battery_workqueue,
708 &cw_bat->battery_delay_work, msecs_to_jiffies(10));
712 static int __maybe_unused cw_bat_suspend(struct device *dev)
714 struct i2c_client *client = to_i2c_client(dev);
715 struct cw_battery *cw_bat = i2c_get_clientdata(client);
717 cancel_delayed_work_sync(&cw_bat->battery_delay_work);
721 static int __maybe_unused cw_bat_resume(struct device *dev)
723 struct i2c_client *client = to_i2c_client(dev);
724 struct cw_battery *cw_bat = i2c_get_clientdata(client);
726 queue_delayed_work(cw_bat->battery_workqueue,
727 &cw_bat->battery_delay_work, 0);
731 static SIMPLE_DEV_PM_OPS(cw_bat_pm_ops, cw_bat_suspend, cw_bat_resume);
733 static const struct i2c_device_id cw_bat_id_table[] = {
738 static const struct of_device_id cw2015_of_match[] = {
739 { .compatible = "cellwise,cw2015" },
742 MODULE_DEVICE_TABLE(of, cw2015_of_match);
744 static struct i2c_driver cw_bat_driver = {
747 .of_match_table = cw2015_of_match,
748 .pm = &cw_bat_pm_ops,
750 .probe = cw_bat_probe,
751 .id_table = cw_bat_id_table,
754 module_i2c_driver(cw_bat_driver);
756 MODULE_AUTHOR("xhc<xhc@rock-chips.com>");
757 MODULE_AUTHOR("Tobias Schramm <t.schramm@manjaro.org>");
758 MODULE_DESCRIPTION("cw2015/cw2013 battery driver");
759 MODULE_LICENSE("GPL");