1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // max8997_charger.c - Power supply consumer driver for the Maxim 8997/8966
4 //
5 //  Copyright (C) 2011 Samsung Electronics
6 //  MyungJoo Ham <myungjoo.ham@samsung.com>
7 
8 #include <linux/err.h>
9 #include <linux/module.h>
10 #include <linux/slab.h>
11 #include <linux/platform_device.h>
12 #include <linux/power_supply.h>
13 #include <linux/mfd/max8997.h>
14 #include <linux/mfd/max8997-private.h>
15 
16 /* MAX8997_REG_STATUS4 */
17 #define DCINOK_SHIFT		1
18 #define DCINOK_MASK		(1 << DCINOK_SHIFT)
19 #define DETBAT_SHIFT		2
20 #define DETBAT_MASK		(1 << DETBAT_SHIFT)
21 
22 /* MAX8997_REG_MBCCTRL1 */
23 #define TFCH_SHIFT		4
24 #define TFCH_MASK		(7 << TFCH_SHIFT)
25 
26 /* MAX8997_REG_MBCCTRL5 */
27 #define ITOPOFF_SHIFT		0
28 #define ITOPOFF_MASK		(0xF << ITOPOFF_SHIFT)
29 
30 struct charger_data {
31 	struct device *dev;
32 	struct max8997_dev *iodev;
33 	struct power_supply *battery;
34 };
35 
36 static enum power_supply_property max8997_battery_props[] = {
37 	POWER_SUPPLY_PROP_STATUS, /* "FULL", "CHARGING" or "DISCHARGING". */
38 	POWER_SUPPLY_PROP_PRESENT, /* the presence of battery */
39 	POWER_SUPPLY_PROP_ONLINE, /* charger is active or not */
40 };
41 
42 /* Note that the charger control is done by a current regulator "CHARGER" */
43 static int max8997_battery_get_property(struct power_supply *psy,
44 		enum power_supply_property psp,
45 		union power_supply_propval *val)
46 {
47 	struct charger_data *charger = power_supply_get_drvdata(psy);
48 	struct i2c_client *i2c = charger->iodev->i2c;
49 	int ret;
50 	u8 reg;
51 
52 	switch (psp) {
53 	case POWER_SUPPLY_PROP_STATUS:
54 		val->intval = 0;
55 		ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
56 		if (ret)
57 			return ret;
58 		if ((reg & (1 << 0)) == 0x1)
59 			val->intval = POWER_SUPPLY_STATUS_FULL;
60 		else if ((reg & DCINOK_MASK))
61 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
62 		else
63 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
64 
65 		break;
66 	case POWER_SUPPLY_PROP_PRESENT:
67 		val->intval = 0;
68 		ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
69 		if (ret)
70 			return ret;
71 		if ((reg & DETBAT_MASK) == 0x0)
72 			val->intval = 1;
73 
74 		break;
75 	case POWER_SUPPLY_PROP_ONLINE:
76 		val->intval = 0;
77 		ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
78 		if (ret)
79 			return ret;
80 		if (reg & DCINOK_MASK)
81 			val->intval = 1;
82 
83 		break;
84 	default:
85 		return -EINVAL;
86 	}
87 
88 	return 0;
89 }
90 
91 static const struct power_supply_desc max8997_battery_desc = {
92 	.name		= "max8997_pmic",
93 	.type		= POWER_SUPPLY_TYPE_BATTERY,
94 	.get_property	= max8997_battery_get_property,
95 	.properties	= max8997_battery_props,
96 	.num_properties	= ARRAY_SIZE(max8997_battery_props),
97 };
98 
99 static int max8997_battery_probe(struct platform_device *pdev)
100 {
101 	int ret = 0;
102 	struct charger_data *charger;
103 	struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
104 	struct i2c_client *i2c = iodev->i2c;
105 	struct max8997_platform_data *pdata = iodev->pdata;
106 	struct power_supply_config psy_cfg = {};
107 
108 	if (!pdata) {
109 		dev_err(&pdev->dev, "No platform data supplied.\n");
110 		return -EINVAL;
111 	}
112 
113 	if (pdata->eoc_mA) {
114 		int val = (pdata->eoc_mA - 50) / 10;
115 		if (val < 0)
116 			val = 0;
117 		if (val > 0xf)
118 			val = 0xf;
119 
120 		ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL5,
121 				val << ITOPOFF_SHIFT, ITOPOFF_MASK);
122 		if (ret < 0) {
123 			dev_err(&pdev->dev, "Cannot use i2c bus.\n");
124 			return ret;
125 		}
126 	}
127 	switch (pdata->timeout) {
128 	case 5:
129 		ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL1,
130 				0x2 << TFCH_SHIFT, TFCH_MASK);
131 		break;
132 	case 6:
133 		ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL1,
134 				0x3 << TFCH_SHIFT, TFCH_MASK);
135 		break;
136 	case 7:
137 		ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL1,
138 				0x4 << TFCH_SHIFT, TFCH_MASK);
139 		break;
140 	case 0:
141 		ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL1,
142 				0x7 << TFCH_SHIFT, TFCH_MASK);
143 		break;
144 	default:
145 		dev_err(&pdev->dev, "incorrect timeout value (%d)\n",
146 				pdata->timeout);
147 		return -EINVAL;
148 	}
149 	if (ret < 0) {
150 		dev_err(&pdev->dev, "Cannot use i2c bus.\n");
151 		return ret;
152 	}
153 
154 	charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
155 	if (!charger)
156 		return -ENOMEM;
157 
158 	platform_set_drvdata(pdev, charger);
159 
160 	charger->dev = &pdev->dev;
161 	charger->iodev = iodev;
162 
163 	psy_cfg.drv_data = charger;
164 
165 	charger->battery = devm_power_supply_register(&pdev->dev,
166 						 &max8997_battery_desc,
167 						 &psy_cfg);
168 	if (IS_ERR(charger->battery)) {
169 		dev_err(&pdev->dev, "failed: power supply register\n");
170 		return PTR_ERR(charger->battery);
171 	}
172 
173 	return 0;
174 }
175 
176 static const struct platform_device_id max8997_battery_id[] = {
177 	{ "max8997-battery", 0 },
178 	{ }
179 };
180 MODULE_DEVICE_TABLE(platform, max8997_battery_id);
181 
182 static struct platform_driver max8997_battery_driver = {
183 	.driver = {
184 		.name = "max8997-battery",
185 	},
186 	.probe = max8997_battery_probe,
187 	.id_table = max8997_battery_id,
188 };
189 module_platform_driver(max8997_battery_driver);
190 
191 MODULE_DESCRIPTION("MAXIM 8997/8966 battery control driver");
192 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
193 MODULE_LICENSE("GPL");
194