1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2018 Spreadtrum Communications Inc.
3
4 #include <linux/module.h>
5 #include <linux/platform_device.h>
6 #include <linux/power_supply.h>
7 #include <linux/usb/phy.h>
8 #include <linux/regmap.h>
9 #include <linux/notifier.h>
10 #include <linux/of.h>
11
12 /* PMIC global registers definition */
13 #define SC2731_CHARGE_STATUS 0xedc
14 #define SC2731_CHARGE_FULL BIT(4)
15 #define SC2731_MODULE_EN1 0xc0c
16 #define SC2731_CHARGE_EN BIT(5)
17
18 /* SC2731 switch charger registers definition */
19 #define SC2731_CHG_CFG0 0x0
20 #define SC2731_CHG_CFG1 0x4
21 #define SC2731_CHG_CFG2 0x8
22 #define SC2731_CHG_CFG3 0xc
23 #define SC2731_CHG_CFG4 0x10
24 #define SC2731_CHG_CFG5 0x28
25
26 /* SC2731_CHG_CFG0 register definition */
27 #define SC2731_PRECHG_RNG_SHIFT 11
28 #define SC2731_PRECHG_RNG_MASK GENMASK(12, 11)
29
30 #define SC2731_TERMINATION_VOL_MASK GENMASK(2, 1)
31 #define SC2731_TERMINATION_VOL_SHIFT 1
32 #define SC2731_TERMINATION_VOL_CAL_MASK GENMASK(8, 3)
33 #define SC2731_TERMINATION_VOL_CAL_SHIFT 3
34 #define SC2731_TERMINATION_CUR_MASK GENMASK(2, 0)
35
36 #define SC2731_CC_EN BIT(13)
37 #define SC2731_CHARGER_PD BIT(0)
38
39 /* SC2731_CHG_CFG1 register definition */
40 #define SC2731_CUR_MASK GENMASK(5, 0)
41
42 /* SC2731_CHG_CFG5 register definition */
43 #define SC2731_CUR_LIMIT_SHIFT 8
44 #define SC2731_CUR_LIMIT_MASK GENMASK(9, 8)
45
46 /* Default current definition (unit is mA) */
47 #define SC2731_CURRENT_LIMIT_100 100
48 #define SC2731_CURRENT_LIMIT_500 500
49 #define SC2731_CURRENT_LIMIT_900 900
50 #define SC2731_CURRENT_LIMIT_2000 2000
51 #define SC2731_CURRENT_PRECHG 450
52 #define SC2731_CURRENT_STEP 50
53
54 struct sc2731_charger_info {
55 struct device *dev;
56 struct regmap *regmap;
57 struct usb_phy *usb_phy;
58 struct notifier_block usb_notify;
59 struct power_supply *psy_usb;
60 struct work_struct work;
61 struct mutex lock;
62 bool charging;
63 u32 base;
64 u32 limit;
65 };
66
sc2731_charger_stop_charge(struct sc2731_charger_info * info)67 static void sc2731_charger_stop_charge(struct sc2731_charger_info *info)
68 {
69 regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
70 SC2731_CC_EN, 0);
71
72 regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
73 SC2731_CHARGER_PD, SC2731_CHARGER_PD);
74 }
75
sc2731_charger_start_charge(struct sc2731_charger_info * info)76 static int sc2731_charger_start_charge(struct sc2731_charger_info *info)
77 {
78 int ret;
79
80 /* Enable charger constant current mode */
81 ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
82 SC2731_CC_EN, SC2731_CC_EN);
83 if (ret)
84 return ret;
85
86 /* Start charging */
87 return regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
88 SC2731_CHARGER_PD, 0);
89 }
90
sc2731_charger_set_current_limit(struct sc2731_charger_info * info,u32 limit)91 static int sc2731_charger_set_current_limit(struct sc2731_charger_info *info,
92 u32 limit)
93 {
94 u32 val;
95
96 if (limit <= SC2731_CURRENT_LIMIT_100)
97 val = 0;
98 else if (limit <= SC2731_CURRENT_LIMIT_500)
99 val = 3;
100 else if (limit <= SC2731_CURRENT_LIMIT_900)
101 val = 2;
102 else
103 val = 1;
104
105 return regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG5,
106 SC2731_CUR_LIMIT_MASK,
107 val << SC2731_CUR_LIMIT_SHIFT);
108 }
109
sc2731_charger_set_current(struct sc2731_charger_info * info,u32 cur)110 static int sc2731_charger_set_current(struct sc2731_charger_info *info, u32 cur)
111 {
112 u32 val;
113 int ret;
114
115 if (cur > SC2731_CURRENT_LIMIT_2000)
116 cur = SC2731_CURRENT_LIMIT_2000;
117 else if (cur < SC2731_CURRENT_PRECHG)
118 cur = SC2731_CURRENT_PRECHG;
119
120 /* Calculate the step value, each step is 50 mA */
121 val = (cur - SC2731_CURRENT_PRECHG) / SC2731_CURRENT_STEP;
122
123 /* Set pre-charge current as 450 mA */
124 ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
125 SC2731_PRECHG_RNG_MASK,
126 0x3 << SC2731_PRECHG_RNG_SHIFT);
127 if (ret)
128 return ret;
129
130 return regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG1,
131 SC2731_CUR_MASK, val);
132 }
133
sc2731_charger_get_status(struct sc2731_charger_info * info)134 static int sc2731_charger_get_status(struct sc2731_charger_info *info)
135 {
136 u32 val;
137 int ret;
138
139 ret = regmap_read(info->regmap, SC2731_CHARGE_STATUS, &val);
140 if (ret)
141 return ret;
142
143 if (val & SC2731_CHARGE_FULL)
144 return POWER_SUPPLY_STATUS_FULL;
145
146 return POWER_SUPPLY_STATUS_CHARGING;
147 }
148
sc2731_charger_get_current(struct sc2731_charger_info * info,u32 * cur)149 static int sc2731_charger_get_current(struct sc2731_charger_info *info,
150 u32 *cur)
151 {
152 int ret;
153 u32 val;
154
155 ret = regmap_read(info->regmap, info->base + SC2731_CHG_CFG1, &val);
156 if (ret)
157 return ret;
158
159 val &= SC2731_CUR_MASK;
160 *cur = val * SC2731_CURRENT_STEP + SC2731_CURRENT_PRECHG;
161
162 return 0;
163 }
164
sc2731_charger_get_current_limit(struct sc2731_charger_info * info,u32 * cur)165 static int sc2731_charger_get_current_limit(struct sc2731_charger_info *info,
166 u32 *cur)
167 {
168 int ret;
169 u32 val;
170
171 ret = regmap_read(info->regmap, info->base + SC2731_CHG_CFG5, &val);
172 if (ret)
173 return ret;
174
175 val = (val & SC2731_CUR_LIMIT_MASK) >> SC2731_CUR_LIMIT_SHIFT;
176
177 switch (val) {
178 case 0:
179 *cur = SC2731_CURRENT_LIMIT_100;
180 break;
181
182 case 1:
183 *cur = SC2731_CURRENT_LIMIT_2000;
184 break;
185
186 case 2:
187 *cur = SC2731_CURRENT_LIMIT_900;
188 break;
189
190 case 3:
191 *cur = SC2731_CURRENT_LIMIT_500;
192 break;
193
194 default:
195 return -EINVAL;
196 }
197
198 return 0;
199 }
200
201 static int
sc2731_charger_usb_set_property(struct power_supply * psy,enum power_supply_property psp,const union power_supply_propval * val)202 sc2731_charger_usb_set_property(struct power_supply *psy,
203 enum power_supply_property psp,
204 const union power_supply_propval *val)
205 {
206 struct sc2731_charger_info *info = power_supply_get_drvdata(psy);
207 int ret;
208
209 mutex_lock(&info->lock);
210
211 if (!info->charging) {
212 mutex_unlock(&info->lock);
213 return -ENODEV;
214 }
215
216 switch (psp) {
217 case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
218 ret = sc2731_charger_set_current(info, val->intval / 1000);
219 if (ret < 0)
220 dev_err(info->dev, "set charge current failed\n");
221 break;
222
223 case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
224 ret = sc2731_charger_set_current_limit(info,
225 val->intval / 1000);
226 if (ret < 0)
227 dev_err(info->dev, "set input current limit failed\n");
228 break;
229
230 default:
231 ret = -EINVAL;
232 }
233
234 mutex_unlock(&info->lock);
235 return ret;
236 }
237
sc2731_charger_usb_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)238 static int sc2731_charger_usb_get_property(struct power_supply *psy,
239 enum power_supply_property psp,
240 union power_supply_propval *val)
241 {
242 struct sc2731_charger_info *info = power_supply_get_drvdata(psy);
243 int ret = 0;
244 u32 cur;
245
246 mutex_lock(&info->lock);
247
248 switch (psp) {
249 case POWER_SUPPLY_PROP_STATUS:
250 if (info->charging)
251 val->intval = sc2731_charger_get_status(info);
252 else
253 val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
254 break;
255
256 case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
257 if (!info->charging) {
258 val->intval = 0;
259 } else {
260 ret = sc2731_charger_get_current(info, &cur);
261 if (ret)
262 goto out;
263
264 val->intval = cur * 1000;
265 }
266 break;
267
268 case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
269 if (!info->charging) {
270 val->intval = 0;
271 } else {
272 ret = sc2731_charger_get_current_limit(info, &cur);
273 if (ret)
274 goto out;
275
276 val->intval = cur * 1000;
277 }
278 break;
279
280 default:
281 ret = -EINVAL;
282 }
283
284 out:
285 mutex_unlock(&info->lock);
286 return ret;
287 }
288
sc2731_charger_property_is_writeable(struct power_supply * psy,enum power_supply_property psp)289 static int sc2731_charger_property_is_writeable(struct power_supply *psy,
290 enum power_supply_property psp)
291 {
292 int ret;
293
294 switch (psp) {
295 case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
296 case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
297 ret = 1;
298 break;
299
300 default:
301 ret = 0;
302 }
303
304 return ret;
305 }
306
307 static enum power_supply_property sc2731_usb_props[] = {
308 POWER_SUPPLY_PROP_STATUS,
309 POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
310 POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,
311 };
312
313 static const struct power_supply_desc sc2731_charger_desc = {
314 .name = "sc2731_charger",
315 .type = POWER_SUPPLY_TYPE_USB,
316 .properties = sc2731_usb_props,
317 .num_properties = ARRAY_SIZE(sc2731_usb_props),
318 .get_property = sc2731_charger_usb_get_property,
319 .set_property = sc2731_charger_usb_set_property,
320 .property_is_writeable = sc2731_charger_property_is_writeable,
321 };
322
sc2731_charger_work(struct work_struct * data)323 static void sc2731_charger_work(struct work_struct *data)
324 {
325 struct sc2731_charger_info *info =
326 container_of(data, struct sc2731_charger_info, work);
327 int ret;
328
329 mutex_lock(&info->lock);
330
331 if (info->limit > 0 && !info->charging) {
332 /* set current limitation and start to charge */
333 ret = sc2731_charger_set_current_limit(info, info->limit);
334 if (ret)
335 goto out;
336
337 ret = sc2731_charger_set_current(info, info->limit);
338 if (ret)
339 goto out;
340
341 ret = sc2731_charger_start_charge(info);
342 if (ret)
343 goto out;
344
345 info->charging = true;
346 } else if (!info->limit && info->charging) {
347 /* Stop charging */
348 info->charging = false;
349 sc2731_charger_stop_charge(info);
350 }
351
352 out:
353 mutex_unlock(&info->lock);
354 }
355
sc2731_charger_usb_change(struct notifier_block * nb,unsigned long limit,void * data)356 static int sc2731_charger_usb_change(struct notifier_block *nb,
357 unsigned long limit, void *data)
358 {
359 struct sc2731_charger_info *info =
360 container_of(nb, struct sc2731_charger_info, usb_notify);
361
362 info->limit = limit;
363
364 schedule_work(&info->work);
365
366 return NOTIFY_OK;
367 }
368
sc2731_charger_hw_init(struct sc2731_charger_info * info)369 static int sc2731_charger_hw_init(struct sc2731_charger_info *info)
370 {
371 struct power_supply_battery_info bat_info = { };
372 u32 term_currrent, term_voltage, cur_val, vol_val;
373 int ret;
374
375 /* Enable charger module */
376 ret = regmap_update_bits(info->regmap, SC2731_MODULE_EN1,
377 SC2731_CHARGE_EN, SC2731_CHARGE_EN);
378 if (ret)
379 return ret;
380
381 ret = power_supply_get_battery_info(info->psy_usb, &bat_info);
382 if (ret) {
383 dev_warn(info->dev, "no battery information is supplied\n");
384
385 /*
386 * If no battery information is supplied, we should set
387 * default charge termination current to 120 mA, and default
388 * charge termination voltage to 4.35V.
389 */
390 cur_val = 0x2;
391 vol_val = 0x1;
392 } else {
393 term_currrent = bat_info.charge_term_current_ua / 1000;
394
395 if (term_currrent <= 90)
396 cur_val = 0;
397 else if (term_currrent >= 265)
398 cur_val = 0x7;
399 else
400 cur_val = ((term_currrent - 90) / 25) + 1;
401
402 term_voltage = bat_info.constant_charge_voltage_max_uv / 1000;
403
404 if (term_voltage > 4500)
405 term_voltage = 4500;
406
407 if (term_voltage > 4200)
408 vol_val = (term_voltage - 4200) / 100;
409 else
410 vol_val = 0;
411
412 power_supply_put_battery_info(info->psy_usb, &bat_info);
413 }
414
415 /* Set charge termination current */
416 ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG2,
417 SC2731_TERMINATION_CUR_MASK, cur_val);
418 if (ret)
419 goto error;
420
421 /* Set charge termination voltage */
422 ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
423 SC2731_TERMINATION_VOL_MASK |
424 SC2731_TERMINATION_VOL_CAL_MASK,
425 (vol_val << SC2731_TERMINATION_VOL_SHIFT) |
426 (0x6 << SC2731_TERMINATION_VOL_CAL_SHIFT));
427 if (ret)
428 goto error;
429
430 return 0;
431
432 error:
433 regmap_update_bits(info->regmap, SC2731_MODULE_EN1, SC2731_CHARGE_EN, 0);
434 return ret;
435 }
436
sc2731_charger_detect_status(struct sc2731_charger_info * info)437 static void sc2731_charger_detect_status(struct sc2731_charger_info *info)
438 {
439 unsigned int min, max;
440
441 /*
442 * If the USB charger status has been USB_CHARGER_PRESENT before
443 * registering the notifier, we should start to charge with getting
444 * the charge current.
445 */
446 if (info->usb_phy->chg_state != USB_CHARGER_PRESENT)
447 return;
448
449 usb_phy_get_charger_current(info->usb_phy, &min, &max);
450 info->limit = min;
451
452 schedule_work(&info->work);
453 }
454
sc2731_charger_probe(struct platform_device * pdev)455 static int sc2731_charger_probe(struct platform_device *pdev)
456 {
457 struct device_node *np = pdev->dev.of_node;
458 struct sc2731_charger_info *info;
459 struct power_supply_config charger_cfg = { };
460 int ret;
461
462 info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
463 if (!info)
464 return -ENOMEM;
465
466 mutex_init(&info->lock);
467 info->dev = &pdev->dev;
468 INIT_WORK(&info->work, sc2731_charger_work);
469
470 info->regmap = dev_get_regmap(pdev->dev.parent, NULL);
471 if (!info->regmap) {
472 dev_err(&pdev->dev, "failed to get charger regmap\n");
473 return -ENODEV;
474 }
475
476 ret = of_property_read_u32(np, "reg", &info->base);
477 if (ret) {
478 dev_err(&pdev->dev, "failed to get register address\n");
479 return -ENODEV;
480 }
481
482 charger_cfg.drv_data = info;
483 charger_cfg.of_node = np;
484 info->psy_usb = devm_power_supply_register(&pdev->dev,
485 &sc2731_charger_desc,
486 &charger_cfg);
487 if (IS_ERR(info->psy_usb)) {
488 dev_err(&pdev->dev, "failed to register power supply\n");
489 return PTR_ERR(info->psy_usb);
490 }
491
492 ret = sc2731_charger_hw_init(info);
493 if (ret)
494 return ret;
495
496 info->usb_phy = devm_usb_get_phy_by_phandle(&pdev->dev, "phys", 0);
497 if (IS_ERR(info->usb_phy)) {
498 dev_err(&pdev->dev, "failed to find USB phy\n");
499 return PTR_ERR(info->usb_phy);
500 }
501
502 info->usb_notify.notifier_call = sc2731_charger_usb_change;
503 ret = usb_register_notifier(info->usb_phy, &info->usb_notify);
504 if (ret) {
505 dev_err(&pdev->dev, "failed to register notifier: %d\n", ret);
506 return ret;
507 }
508
509 sc2731_charger_detect_status(info);
510
511 return 0;
512 }
513
sc2731_charger_remove(struct platform_device * pdev)514 static int sc2731_charger_remove(struct platform_device *pdev)
515 {
516 struct sc2731_charger_info *info = platform_get_drvdata(pdev);
517
518 usb_unregister_notifier(info->usb_phy, &info->usb_notify);
519
520 return 0;
521 }
522
523 static const struct of_device_id sc2731_charger_of_match[] = {
524 { .compatible = "sprd,sc2731-charger", },
525 { }
526 };
527
528 static struct platform_driver sc2731_charger_driver = {
529 .driver = {
530 .name = "sc2731-charger",
531 .of_match_table = sc2731_charger_of_match,
532 },
533 .probe = sc2731_charger_probe,
534 .remove = sc2731_charger_remove,
535 };
536
537 module_platform_driver(sc2731_charger_driver);
538
539 MODULE_DESCRIPTION("Spreadtrum SC2731 Charger Driver");
540 MODULE_LICENSE("GPL v2");
541