tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/*
2 * Battery charger driver for the Maxim 14577
3 *
4 * Copyright (C) 2013 Samsung Electronics
5 * Krzysztof Kozlowski <k.kozlowski@samsung.com>
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
18#include <linux/module.h>
19#include <linux/platform_device.h>
20#include <linux/power_supply.h>
21#include <linux/mfd/max14577-private.h>
22
23struct max14577_charger {
24 struct device *dev;
25 struct max14577 *max14577;
26 struct power_supply charger;
27
28 unsigned int charging_state;
29 unsigned int battery_state;
30};
31
32static int max14577_get_charger_state(struct max14577_charger *chg)
33{
34 struct regmap *rmap = chg->max14577->regmap;
35 int state = POWER_SUPPLY_STATUS_DISCHARGING;
36 u8 reg_data;
37
38 /*
39 * Charging occurs only if:
40 * - CHGCTRL2/MBCHOSTEN == 1
41 * - STATUS2/CGMBC == 1
42 *
43 * TODO:
44 * - handle FULL after Top-off timer (EOC register may be off
45 * and the charger won't be charging although MBCHOSTEN is on)
46 * - handle properly dead-battery charging (respect timer)
47 * - handle timers (fast-charge and prequal) /MBCCHGERR/
48 */
49 max14577_read_reg(rmap, MAX14577_CHG_REG_CHG_CTRL2, ®_data);
50 if ((reg_data & CHGCTRL2_MBCHOSTEN_MASK) == 0)
51 goto state_set;
52
53 max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, ®_data);
54 if (reg_data & STATUS3_CGMBC_MASK) {
55 /* Charger or USB-cable is connected */
56 if (reg_data & STATUS3_EOC_MASK)
57 state = POWER_SUPPLY_STATUS_FULL;
58 else
59 state = POWER_SUPPLY_STATUS_CHARGING;
60 goto state_set;
61 }
62
63state_set:
64 chg->charging_state = state;
65 return state;
66}
67
68/*
69 * Supported charge types:
70 * - POWER_SUPPLY_CHARGE_TYPE_NONE
71 * - POWER_SUPPLY_CHARGE_TYPE_FAST
72 */
73static int max14577_get_charge_type(struct max14577_charger *chg)
74{
75 /*
76 * TODO: CHARGE_TYPE_TRICKLE (VCHGR_RC or EOC)?
77 * As spec says:
78 * [after reaching EOC interrupt]
79 * "When the battery is fully charged, the 30-minute (typ)
80 * top-off timer starts. The device continues to trickle
81 * charge the battery until the top-off timer runs out."
82 */
83 if (max14577_get_charger_state(chg) == POWER_SUPPLY_STATUS_CHARGING)
84 return POWER_SUPPLY_CHARGE_TYPE_FAST;
85 return POWER_SUPPLY_CHARGE_TYPE_NONE;
86}
87
88static int max14577_get_online(struct max14577_charger *chg)
89{
90 struct regmap *rmap = chg->max14577->regmap;
91 u8 reg_data;
92
93 max14577_read_reg(rmap, MAX14577_MUIC_REG_STATUS2, ®_data);
94 reg_data = ((reg_data & STATUS2_CHGTYP_MASK) >> STATUS2_CHGTYP_SHIFT);
95 switch (reg_data) {
96 case MAX14577_CHARGER_TYPE_USB:
97 case MAX14577_CHARGER_TYPE_DEDICATED_CHG:
98 case MAX14577_CHARGER_TYPE_SPECIAL_500MA:
99 case MAX14577_CHARGER_TYPE_SPECIAL_1A:
100 case MAX14577_CHARGER_TYPE_DEAD_BATTERY:
101 return 1;
102 case MAX14577_CHARGER_TYPE_NONE:
103 case MAX14577_CHARGER_TYPE_DOWNSTREAM_PORT:
104 case MAX14577_CHARGER_TYPE_RESERVED:
105 default:
106 return 0;
107 }
108}
109
110/*
111 * Supported health statuses:
112 * - POWER_SUPPLY_HEALTH_DEAD
113 * - POWER_SUPPLY_HEALTH_OVERVOLTAGE
114 * - POWER_SUPPLY_HEALTH_GOOD
115 */
116static int max14577_get_battery_health(struct max14577_charger *chg)
117{
118 struct regmap *rmap = chg->max14577->regmap;
119 int state = POWER_SUPPLY_HEALTH_GOOD;
120 u8 reg_data;
121
122 max14577_read_reg(rmap, MAX14577_MUIC_REG_STATUS2, ®_data);
123 reg_data = ((reg_data & STATUS2_CHGTYP_MASK) >> STATUS2_CHGTYP_SHIFT);
124 if (reg_data == MAX14577_CHARGER_TYPE_DEAD_BATTERY) {
125 state = POWER_SUPPLY_HEALTH_DEAD;
126 goto state_set;
127 }
128
129 max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, ®_data);
130 if (reg_data & STATUS3_OVP_MASK) {
131 state = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
132 goto state_set;
133 }
134
135state_set:
136 chg->battery_state = state;
137 return state;
138}
139
140/*
141 * Always returns 1.
142 * The max14577 chip doesn't report any status of battery presence.
143 * Lets assume that it will always be used with some battery.
144 */
145static int max14577_get_present(struct max14577_charger *chg)
146{
147 return 1;
148}
149
150/*
151 * Sets charger registers to proper and safe default values.
152 * Some of these values are equal to defaults in MAX14577E
153 * data sheet but there are minor differences.
154 */
155static void max14577_charger_reg_init(struct max14577_charger *chg)
156{
157 struct regmap *rmap = chg->max14577->regmap;
158 u8 reg_data;
159
160 /*
161 * Charger-Type Manual Detection, default off (set CHGTYPMAN to 0)
162 * Charger-Detection Enable, default on (set CHGDETEN to 1)
163 * Combined mask of CHGDETEN and CHGTYPMAN will zero the CHGTYPMAN bit
164 */
165 reg_data = 0x1 << CDETCTRL1_CHGDETEN_SHIFT;
166 max14577_update_reg(rmap, MAX14577_REG_CDETCTRL1,
167 CDETCTRL1_CHGDETEN_MASK | CDETCTRL1_CHGTYPMAN_MASK,
168 reg_data);
169
170 /* Battery Fast-Charge Timer, from SM-V700: 6hrs */
171 reg_data = 0x3 << CHGCTRL1_TCHW_SHIFT;
172 max14577_write_reg(rmap, MAX14577_REG_CHGCTRL1, reg_data);
173
174 /*
175 * Wall-Adapter Rapid Charge, default on
176 * Battery-Charger, default on
177 */
178 reg_data = 0x1 << CHGCTRL2_VCHGR_RC_SHIFT;
179 reg_data |= 0x1 << CHGCTRL2_MBCHOSTEN_SHIFT;
180 max14577_write_reg(rmap, MAX14577_REG_CHGCTRL2, reg_data);
181
182 /* Battery-Charger Constant Voltage (CV) Mode, from SM-V700: 4.35V */
183 reg_data = 0xf << CHGCTRL3_MBCCVWRC_SHIFT;
184 max14577_write_reg(rmap, MAX14577_REG_CHGCTRL3, reg_data);
185
186 /*
187 * Fast Battery-Charge Current Low, default 200-950mA
188 * Fast Battery-Charge Current High, from SM-V700: 450mA
189 */
190 reg_data = 0x1 << CHGCTRL4_MBCICHWRCL_SHIFT;
191 reg_data |= 0x5 << CHGCTRL4_MBCICHWRCH_SHIFT;
192 max14577_write_reg(rmap, MAX14577_REG_CHGCTRL4, reg_data);
193
194 /* End-of-Charge Current, from SM-V700: 50mA */
195 reg_data = 0x0 << CHGCTRL5_EOCS_SHIFT;
196 max14577_write_reg(rmap, MAX14577_REG_CHGCTRL5, reg_data);
197
198 /* Auto Charging Stop, default off */
199 reg_data = 0x0 << CHGCTRL6_AUTOSTOP_SHIFT;
200 max14577_write_reg(rmap, MAX14577_REG_CHGCTRL6, reg_data);
201
202 /* Overvoltage-Protection Threshold, from SM-V700: 6.5V */
203 reg_data = 0x2 << CHGCTRL7_OTPCGHCVS_SHIFT;
204 max14577_write_reg(rmap, MAX14577_REG_CHGCTRL7, reg_data);
205}
206
207/* Support property from charger */
208static enum power_supply_property max14577_charger_props[] = {
209 POWER_SUPPLY_PROP_STATUS,
210 POWER_SUPPLY_PROP_CHARGE_TYPE,
211 POWER_SUPPLY_PROP_HEALTH,
212 POWER_SUPPLY_PROP_PRESENT,
213 POWER_SUPPLY_PROP_ONLINE,
214 POWER_SUPPLY_PROP_MODEL_NAME,
215 POWER_SUPPLY_PROP_MANUFACTURER,
216};
217
218static const char *model_name = "MAX14577";
219static const char *manufacturer = "Maxim Integrated";
220
221static int max14577_charger_get_property(struct power_supply *psy,
222 enum power_supply_property psp,
223 union power_supply_propval *val)
224{
225 struct max14577_charger *chg = container_of(psy,
226 struct max14577_charger,
227 charger);
228 int ret = 0;
229
230 switch (psp) {
231 case POWER_SUPPLY_PROP_STATUS:
232 val->intval = max14577_get_charger_state(chg);
233 break;
234 case POWER_SUPPLY_PROP_CHARGE_TYPE:
235 val->intval = max14577_get_charge_type(chg);
236 break;
237 case POWER_SUPPLY_PROP_HEALTH:
238 val->intval = max14577_get_battery_health(chg);
239 break;
240 case POWER_SUPPLY_PROP_PRESENT:
241 val->intval = max14577_get_present(chg);
242 break;
243 case POWER_SUPPLY_PROP_ONLINE:
244 val->intval = max14577_get_online(chg);
245 break;
246 case POWER_SUPPLY_PROP_MODEL_NAME:
247 val->strval = model_name;
248 break;
249 case POWER_SUPPLY_PROP_MANUFACTURER:
250 val->strval = manufacturer;
251 break;
252 default:
253 return -EINVAL;
254 }
255
256 return ret;
257}
258
259static int max14577_charger_probe(struct platform_device *pdev)
260{
261 struct max14577_charger *chg;
262 struct max14577 *max14577 = dev_get_drvdata(pdev->dev.parent);
263 int ret;
264
265 chg = devm_kzalloc(&pdev->dev, sizeof(*chg), GFP_KERNEL);
266 if (!chg)
267 return -ENOMEM;
268
269 platform_set_drvdata(pdev, chg);
270 chg->dev = &pdev->dev;
271 chg->max14577 = max14577;
272
273 max14577_charger_reg_init(chg);
274
275 chg->charger.name = "max14577-charger",
276 chg->charger.type = POWER_SUPPLY_TYPE_BATTERY,
277 chg->charger.properties = max14577_charger_props,
278 chg->charger.num_properties = ARRAY_SIZE(max14577_charger_props),
279 chg->charger.get_property = max14577_charger_get_property,
280
281 ret = power_supply_register(&pdev->dev, &chg->charger);
282 if (ret) {
283 dev_err(&pdev->dev, "failed: power supply register\n");
284 return ret;
285 }
286
287 return 0;
288}
289
290static int max14577_charger_remove(struct platform_device *pdev)
291{
292 struct max14577_charger *chg = platform_get_drvdata(pdev);
293
294 power_supply_unregister(&chg->charger);
295
296 return 0;
297}
298
299static struct platform_driver max14577_charger_driver = {
300 .driver = {
301 .owner = THIS_MODULE,
302 .name = "max14577-charger",
303 },
304 .probe = max14577_charger_probe,
305 .remove = max14577_charger_remove,
306};
307module_platform_driver(max14577_charger_driver);
308
309MODULE_AUTHOR("Krzysztof Kozlowski <k.kozlowski@samsung.com>");
310MODULE_DESCRIPTION("MAXIM 14577 charger driver");
311MODULE_LICENSE("GPL");