1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (C) 2018 BayLibre SAS
4 // Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
5 //
6 // Battery charger driver for MAXIM 77650/77651 charger/power-supply.
7
8 #include <linux/i2c.h>
9 #include <linux/interrupt.h>
10 #include <linux/mfd/max77650.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/power_supply.h>
14 #include <linux/regmap.h>
15
16 #define MAX77650_CHARGER_ENABLED BIT(0)
17 #define MAX77650_CHARGER_DISABLED 0x00
18 #define MAX77650_CHARGER_CHG_EN_MASK BIT(0)
19
20 #define MAX77650_CHG_DETAILS_MASK GENMASK(7, 4)
21 #define MAX77650_CHG_DETAILS_BITS(_reg) \
22 (((_reg) & MAX77650_CHG_DETAILS_MASK) >> 4)
23
24 /* Charger is OFF. */
25 #define MAX77650_CHG_OFF 0x00
26 /* Charger is in prequalification mode. */
27 #define MAX77650_CHG_PREQ 0x01
28 /* Charger is in fast-charge constant current mode. */
29 #define MAX77650_CHG_ON_CURR 0x02
30 /* Charger is in JEITA modified fast-charge constant-current mode. */
31 #define MAX77650_CHG_ON_CURR_JEITA 0x03
32 /* Charger is in fast-charge constant-voltage mode. */
33 #define MAX77650_CHG_ON_VOLT 0x04
34 /* Charger is in JEITA modified fast-charge constant-voltage mode. */
35 #define MAX77650_CHG_ON_VOLT_JEITA 0x05
36 /* Charger is in top-off mode. */
37 #define MAX77650_CHG_ON_TOPOFF 0x06
38 /* Charger is in JEITA modified top-off mode. */
39 #define MAX77650_CHG_ON_TOPOFF_JEITA 0x07
40 /* Charger is done. */
41 #define MAX77650_CHG_DONE 0x08
42 /* Charger is JEITA modified done. */
43 #define MAX77650_CHG_DONE_JEITA 0x09
44 /* Charger is suspended due to a prequalification timer fault. */
45 #define MAX77650_CHG_SUSP_PREQ_TIM_FAULT 0x0a
46 /* Charger is suspended due to a fast-charge timer fault. */
47 #define MAX77650_CHG_SUSP_FAST_CHG_TIM_FAULT 0x0b
48 /* Charger is suspended due to a battery temperature fault. */
49 #define MAX77650_CHG_SUSP_BATT_TEMP_FAULT 0x0c
50
51 #define MAX77650_CHGIN_DETAILS_MASK GENMASK(3, 2)
52 #define MAX77650_CHGIN_DETAILS_BITS(_reg) \
53 (((_reg) & MAX77650_CHGIN_DETAILS_MASK) >> 2)
54
55 #define MAX77650_CHGIN_UNDERVOLTAGE_LOCKOUT 0x00
56 #define MAX77650_CHGIN_OVERVOLTAGE_LOCKOUT 0x01
57 #define MAX77650_CHGIN_OKAY 0x11
58
59 #define MAX77650_CHARGER_CHG_MASK BIT(1)
60 #define MAX77650_CHARGER_CHG_CHARGING(_reg) \
61 (((_reg) & MAX77650_CHARGER_CHG_MASK) > 1)
62
63 #define MAX77650_CHARGER_VCHGIN_MIN_MASK 0xc0
64 #define MAX77650_CHARGER_VCHGIN_MIN_SHIFT(_val) ((_val) << 5)
65
66 #define MAX77650_CHARGER_ICHGIN_LIM_MASK 0x1c
67 #define MAX77650_CHARGER_ICHGIN_LIM_SHIFT(_val) ((_val) << 2)
68
69 struct max77650_charger_data {
70 struct regmap *map;
71 struct device *dev;
72 };
73
74 static enum power_supply_property max77650_charger_properties[] = {
75 POWER_SUPPLY_PROP_STATUS,
76 POWER_SUPPLY_PROP_ONLINE,
77 POWER_SUPPLY_PROP_CHARGE_TYPE
78 };
79
80 static const unsigned int max77650_charger_vchgin_min_table[] = {
81 4000000, 4100000, 4200000, 4300000, 4400000, 4500000, 4600000, 4700000
82 };
83
84 static const unsigned int max77650_charger_ichgin_lim_table[] = {
85 95000, 190000, 285000, 380000, 475000
86 };
87
max77650_charger_set_vchgin_min(struct max77650_charger_data * chg,unsigned int val)88 static int max77650_charger_set_vchgin_min(struct max77650_charger_data *chg,
89 unsigned int val)
90 {
91 int i, rv;
92
93 for (i = 0; i < ARRAY_SIZE(max77650_charger_vchgin_min_table); i++) {
94 if (val == max77650_charger_vchgin_min_table[i]) {
95 rv = regmap_update_bits(chg->map,
96 MAX77650_REG_CNFG_CHG_B,
97 MAX77650_CHARGER_VCHGIN_MIN_MASK,
98 MAX77650_CHARGER_VCHGIN_MIN_SHIFT(i));
99 if (rv)
100 return rv;
101
102 return 0;
103 }
104 }
105
106 return -EINVAL;
107 }
108
max77650_charger_set_ichgin_lim(struct max77650_charger_data * chg,unsigned int val)109 static int max77650_charger_set_ichgin_lim(struct max77650_charger_data *chg,
110 unsigned int val)
111 {
112 int i, rv;
113
114 for (i = 0; i < ARRAY_SIZE(max77650_charger_ichgin_lim_table); i++) {
115 if (val == max77650_charger_ichgin_lim_table[i]) {
116 rv = regmap_update_bits(chg->map,
117 MAX77650_REG_CNFG_CHG_B,
118 MAX77650_CHARGER_ICHGIN_LIM_MASK,
119 MAX77650_CHARGER_ICHGIN_LIM_SHIFT(i));
120 if (rv)
121 return rv;
122
123 return 0;
124 }
125 }
126
127 return -EINVAL;
128 }
129
max77650_charger_enable(struct max77650_charger_data * chg)130 static int max77650_charger_enable(struct max77650_charger_data *chg)
131 {
132 int rv;
133
134 rv = regmap_update_bits(chg->map,
135 MAX77650_REG_CNFG_CHG_B,
136 MAX77650_CHARGER_CHG_EN_MASK,
137 MAX77650_CHARGER_ENABLED);
138 if (rv)
139 dev_err(chg->dev, "unable to enable the charger: %d\n", rv);
140
141 return rv;
142 }
143
max77650_charger_disable(struct max77650_charger_data * chg)144 static void max77650_charger_disable(struct max77650_charger_data *chg)
145 {
146 int rv;
147
148 rv = regmap_update_bits(chg->map,
149 MAX77650_REG_CNFG_CHG_B,
150 MAX77650_CHARGER_CHG_EN_MASK,
151 MAX77650_CHARGER_DISABLED);
152 if (rv)
153 dev_err(chg->dev, "unable to disable the charger: %d\n", rv);
154 }
155
max77650_charger_check_status(int irq,void * data)156 static irqreturn_t max77650_charger_check_status(int irq, void *data)
157 {
158 struct max77650_charger_data *chg = data;
159 int rv, reg;
160
161 rv = regmap_read(chg->map, MAX77650_REG_STAT_CHG_B, ®);
162 if (rv) {
163 dev_err(chg->dev,
164 "unable to read the charger status: %d\n", rv);
165 return IRQ_HANDLED;
166 }
167
168 switch (MAX77650_CHGIN_DETAILS_BITS(reg)) {
169 case MAX77650_CHGIN_UNDERVOLTAGE_LOCKOUT:
170 dev_err(chg->dev, "undervoltage lockout detected, disabling charger\n");
171 max77650_charger_disable(chg);
172 break;
173 case MAX77650_CHGIN_OVERVOLTAGE_LOCKOUT:
174 dev_err(chg->dev, "overvoltage lockout detected, disabling charger\n");
175 max77650_charger_disable(chg);
176 break;
177 case MAX77650_CHGIN_OKAY:
178 max77650_charger_enable(chg);
179 break;
180 default:
181 /* May be 0x10 - debouncing */
182 break;
183 }
184
185 return IRQ_HANDLED;
186 }
187
max77650_charger_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)188 static int max77650_charger_get_property(struct power_supply *psy,
189 enum power_supply_property psp,
190 union power_supply_propval *val)
191 {
192 struct max77650_charger_data *chg = power_supply_get_drvdata(psy);
193 int rv, reg;
194
195 switch (psp) {
196 case POWER_SUPPLY_PROP_STATUS:
197 rv = regmap_read(chg->map, MAX77650_REG_STAT_CHG_B, ®);
198 if (rv)
199 return rv;
200
201 if (MAX77650_CHARGER_CHG_CHARGING(reg)) {
202 val->intval = POWER_SUPPLY_STATUS_CHARGING;
203 break;
204 }
205
206 switch (MAX77650_CHG_DETAILS_BITS(reg)) {
207 case MAX77650_CHG_OFF:
208 case MAX77650_CHG_SUSP_PREQ_TIM_FAULT:
209 case MAX77650_CHG_SUSP_FAST_CHG_TIM_FAULT:
210 case MAX77650_CHG_SUSP_BATT_TEMP_FAULT:
211 val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
212 break;
213 case MAX77650_CHG_PREQ:
214 case MAX77650_CHG_ON_CURR:
215 case MAX77650_CHG_ON_CURR_JEITA:
216 case MAX77650_CHG_ON_VOLT:
217 case MAX77650_CHG_ON_VOLT_JEITA:
218 case MAX77650_CHG_ON_TOPOFF:
219 case MAX77650_CHG_ON_TOPOFF_JEITA:
220 val->intval = POWER_SUPPLY_STATUS_CHARGING;
221 break;
222 case MAX77650_CHG_DONE:
223 val->intval = POWER_SUPPLY_STATUS_FULL;
224 break;
225 default:
226 val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
227 }
228 break;
229 case POWER_SUPPLY_PROP_ONLINE:
230 rv = regmap_read(chg->map, MAX77650_REG_STAT_CHG_B, ®);
231 if (rv)
232 return rv;
233
234 val->intval = MAX77650_CHARGER_CHG_CHARGING(reg);
235 break;
236 case POWER_SUPPLY_PROP_CHARGE_TYPE:
237 rv = regmap_read(chg->map, MAX77650_REG_STAT_CHG_B, ®);
238 if (rv)
239 return rv;
240
241 if (!MAX77650_CHARGER_CHG_CHARGING(reg)) {
242 val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE;
243 break;
244 }
245
246 switch (MAX77650_CHG_DETAILS_BITS(reg)) {
247 case MAX77650_CHG_PREQ:
248 case MAX77650_CHG_ON_CURR:
249 case MAX77650_CHG_ON_CURR_JEITA:
250 case MAX77650_CHG_ON_VOLT:
251 case MAX77650_CHG_ON_VOLT_JEITA:
252 val->intval = POWER_SUPPLY_CHARGE_TYPE_FAST;
253 break;
254 case MAX77650_CHG_ON_TOPOFF:
255 case MAX77650_CHG_ON_TOPOFF_JEITA:
256 val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
257 break;
258 default:
259 val->intval = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
260 }
261 break;
262 default:
263 return -EINVAL;
264 }
265
266 return 0;
267 }
268
269 static const struct power_supply_desc max77650_battery_desc = {
270 .name = "max77650",
271 .type = POWER_SUPPLY_TYPE_USB,
272 .get_property = max77650_charger_get_property,
273 .properties = max77650_charger_properties,
274 .num_properties = ARRAY_SIZE(max77650_charger_properties),
275 };
276
max77650_charger_probe(struct platform_device * pdev)277 static int max77650_charger_probe(struct platform_device *pdev)
278 {
279 struct power_supply_config pscfg = {};
280 struct max77650_charger_data *chg;
281 struct power_supply *battery;
282 struct device *dev, *parent;
283 int rv, chg_irq, chgin_irq;
284 unsigned int prop;
285
286 dev = &pdev->dev;
287 parent = dev->parent;
288
289 chg = devm_kzalloc(dev, sizeof(*chg), GFP_KERNEL);
290 if (!chg)
291 return -ENOMEM;
292
293 platform_set_drvdata(pdev, chg);
294
295 chg->map = dev_get_regmap(parent, NULL);
296 if (!chg->map)
297 return -ENODEV;
298
299 chg->dev = dev;
300
301 pscfg.of_node = dev->of_node;
302 pscfg.drv_data = chg;
303
304 chg_irq = platform_get_irq_byname(pdev, "CHG");
305 if (chg_irq < 0)
306 return chg_irq;
307
308 chgin_irq = platform_get_irq_byname(pdev, "CHGIN");
309 if (chgin_irq < 0)
310 return chgin_irq;
311
312 rv = devm_request_any_context_irq(dev, chg_irq,
313 max77650_charger_check_status,
314 IRQF_ONESHOT, "chg", chg);
315 if (rv < 0)
316 return rv;
317
318 rv = devm_request_any_context_irq(dev, chgin_irq,
319 max77650_charger_check_status,
320 IRQF_ONESHOT, "chgin", chg);
321 if (rv < 0)
322 return rv;
323
324 battery = devm_power_supply_register(dev,
325 &max77650_battery_desc, &pscfg);
326 if (IS_ERR(battery))
327 return PTR_ERR(battery);
328
329 rv = of_property_read_u32(dev->of_node,
330 "input-voltage-min-microvolt", &prop);
331 if (rv == 0) {
332 rv = max77650_charger_set_vchgin_min(chg, prop);
333 if (rv)
334 return rv;
335 }
336
337 rv = of_property_read_u32(dev->of_node,
338 "input-current-limit-microamp", &prop);
339 if (rv == 0) {
340 rv = max77650_charger_set_ichgin_lim(chg, prop);
341 if (rv)
342 return rv;
343 }
344
345 return max77650_charger_enable(chg);
346 }
347
max77650_charger_remove(struct platform_device * pdev)348 static int max77650_charger_remove(struct platform_device *pdev)
349 {
350 struct max77650_charger_data *chg = platform_get_drvdata(pdev);
351
352 max77650_charger_disable(chg);
353
354 return 0;
355 }
356
357 static const struct of_device_id max77650_charger_of_match[] = {
358 { .compatible = "maxim,max77650-charger" },
359 { }
360 };
361 MODULE_DEVICE_TABLE(of, max77650_charger_of_match);
362
363 static struct platform_driver max77650_charger_driver = {
364 .driver = {
365 .name = "max77650-charger",
366 .of_match_table = max77650_charger_of_match,
367 },
368 .probe = max77650_charger_probe,
369 .remove = max77650_charger_remove,
370 };
371 module_platform_driver(max77650_charger_driver);
372
373 MODULE_DESCRIPTION("MAXIM 77650/77651 charger driver");
374 MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
375 MODULE_LICENSE("GPL v2");
376 MODULE_ALIAS("platform:max77650-charger");
377