1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Power supply driver for the goldfish emulator
4  *
5  * Copyright (C) 2008 Google, Inc.
6  * Copyright (C) 2012 Intel, Inc.
7  * Copyright (C) 2013 Intel, Inc.
8  * Author: Mike Lockwood <lockwood@android.com>
9  */
10 
11 #include <linux/module.h>
12 #include <linux/err.h>
13 #include <linux/platform_device.h>
14 #include <linux/power_supply.h>
15 #include <linux/types.h>
16 #include <linux/pci.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/acpi.h>
20 
21 struct goldfish_battery_data {
22 	void __iomem *reg_base;
23 	int irq;
24 	spinlock_t lock;
25 
26 	struct power_supply *battery;
27 	struct power_supply *ac;
28 };
29 
30 #define GOLDFISH_BATTERY_READ(data, addr) \
31 	(readl(data->reg_base + addr))
32 #define GOLDFISH_BATTERY_WRITE(data, addr, x) \
33 	(writel(x, data->reg_base + addr))
34 
35 enum {
36 	/* status register */
37 	BATTERY_INT_STATUS	= 0x00,
38 	/* set this to enable IRQ */
39 	BATTERY_INT_ENABLE	= 0x04,
40 
41 	BATTERY_AC_ONLINE	= 0x08,
42 	BATTERY_STATUS		= 0x0C,
43 	BATTERY_HEALTH		= 0x10,
44 	BATTERY_PRESENT		= 0x14,
45 	BATTERY_CAPACITY	= 0x18,
46 	BATTERY_VOLTAGE		= 0x1C,
47 	BATTERY_TEMP		= 0x20,
48 	BATTERY_CHARGE_COUNTER	= 0x24,
49 	BATTERY_VOLTAGE_MAX	= 0x28,
50 	BATTERY_CURRENT_MAX	= 0x2C,
51 	BATTERY_CURRENT_NOW	= 0x30,
52 	BATTERY_CURRENT_AVG	= 0x34,
53 	BATTERY_CHARGE_FULL_UAH	= 0x38,
54 	BATTERY_CYCLE_COUNT	= 0x40,
55 
56 	BATTERY_STATUS_CHANGED	= 1U << 0,
57 	AC_STATUS_CHANGED	= 1U << 1,
58 	BATTERY_INT_MASK	= BATTERY_STATUS_CHANGED | AC_STATUS_CHANGED,
59 };
60 
61 
62 static int goldfish_ac_get_property(struct power_supply *psy,
63 			enum power_supply_property psp,
64 			union power_supply_propval *val)
65 {
66 	struct goldfish_battery_data *data = power_supply_get_drvdata(psy);
67 	int ret = 0;
68 
69 	switch (psp) {
70 	case POWER_SUPPLY_PROP_ONLINE:
71 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_AC_ONLINE);
72 		break;
73 	case POWER_SUPPLY_PROP_VOLTAGE_MAX:
74 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_VOLTAGE_MAX);
75 		break;
76 	case POWER_SUPPLY_PROP_CURRENT_MAX:
77 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_CURRENT_MAX);
78 		break;
79 	default:
80 		ret = -EINVAL;
81 		break;
82 	}
83 	return ret;
84 }
85 
86 static int goldfish_battery_get_property(struct power_supply *psy,
87 				 enum power_supply_property psp,
88 				 union power_supply_propval *val)
89 {
90 	struct goldfish_battery_data *data = power_supply_get_drvdata(psy);
91 	int ret = 0;
92 
93 	switch (psp) {
94 	case POWER_SUPPLY_PROP_STATUS:
95 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_STATUS);
96 		break;
97 	case POWER_SUPPLY_PROP_HEALTH:
98 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_HEALTH);
99 		break;
100 	case POWER_SUPPLY_PROP_PRESENT:
101 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_PRESENT);
102 		break;
103 	case POWER_SUPPLY_PROP_TECHNOLOGY:
104 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
105 		break;
106 	case POWER_SUPPLY_PROP_CAPACITY:
107 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_CAPACITY);
108 		break;
109 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
110 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_VOLTAGE);
111 		break;
112 	case POWER_SUPPLY_PROP_TEMP:
113 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_TEMP);
114 		break;
115 	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
116 		val->intval = GOLDFISH_BATTERY_READ(data,
117 						    BATTERY_CHARGE_COUNTER);
118 		break;
119 	case POWER_SUPPLY_PROP_CURRENT_NOW:
120 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_CURRENT_NOW);
121 		break;
122 	case POWER_SUPPLY_PROP_CURRENT_AVG:
123 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_CURRENT_AVG);
124 		break;
125 	case POWER_SUPPLY_PROP_CHARGE_FULL:
126 		val->intval = GOLDFISH_BATTERY_READ(data,
127 						    BATTERY_CHARGE_FULL_UAH);
128 		break;
129 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
130 		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_CYCLE_COUNT);
131 		break;
132 	default:
133 		ret = -EINVAL;
134 		break;
135 	}
136 
137 	return ret;
138 }
139 
140 static enum power_supply_property goldfish_battery_props[] = {
141 	POWER_SUPPLY_PROP_STATUS,
142 	POWER_SUPPLY_PROP_HEALTH,
143 	POWER_SUPPLY_PROP_PRESENT,
144 	POWER_SUPPLY_PROP_TECHNOLOGY,
145 	POWER_SUPPLY_PROP_CAPACITY,
146 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
147 	POWER_SUPPLY_PROP_TEMP,
148 	POWER_SUPPLY_PROP_CHARGE_COUNTER,
149 	POWER_SUPPLY_PROP_CURRENT_NOW,
150 	POWER_SUPPLY_PROP_CURRENT_AVG,
151 	POWER_SUPPLY_PROP_CHARGE_FULL,
152 	POWER_SUPPLY_PROP_CYCLE_COUNT,
153 };
154 
155 static enum power_supply_property goldfish_ac_props[] = {
156 	POWER_SUPPLY_PROP_ONLINE,
157 	POWER_SUPPLY_PROP_VOLTAGE_MAX,
158 	POWER_SUPPLY_PROP_CURRENT_MAX,
159 };
160 
161 static irqreturn_t goldfish_battery_interrupt(int irq, void *dev_id)
162 {
163 	unsigned long irq_flags;
164 	struct goldfish_battery_data *data = dev_id;
165 	uint32_t status;
166 
167 	spin_lock_irqsave(&data->lock, irq_flags);
168 
169 	/* read status flags, which will clear the interrupt */
170 	status = GOLDFISH_BATTERY_READ(data, BATTERY_INT_STATUS);
171 	status &= BATTERY_INT_MASK;
172 
173 	if (status & BATTERY_STATUS_CHANGED)
174 		power_supply_changed(data->battery);
175 	if (status & AC_STATUS_CHANGED)
176 		power_supply_changed(data->ac);
177 
178 	spin_unlock_irqrestore(&data->lock, irq_flags);
179 	return status ? IRQ_HANDLED : IRQ_NONE;
180 }
181 
182 static const struct power_supply_desc battery_desc = {
183 	.properties	= goldfish_battery_props,
184 	.num_properties	= ARRAY_SIZE(goldfish_battery_props),
185 	.get_property	= goldfish_battery_get_property,
186 	.name		= "battery",
187 	.type		= POWER_SUPPLY_TYPE_BATTERY,
188 };
189 
190 static const struct power_supply_desc ac_desc = {
191 	.properties	= goldfish_ac_props,
192 	.num_properties	= ARRAY_SIZE(goldfish_ac_props),
193 	.get_property	= goldfish_ac_get_property,
194 	.name		= "ac",
195 	.type		= POWER_SUPPLY_TYPE_MAINS,
196 };
197 
198 static int goldfish_battery_probe(struct platform_device *pdev)
199 {
200 	int ret;
201 	struct resource *r;
202 	struct goldfish_battery_data *data;
203 	struct power_supply_config psy_cfg = {};
204 
205 	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
206 	if (data == NULL)
207 		return -ENOMEM;
208 
209 	spin_lock_init(&data->lock);
210 
211 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
212 	if (r == NULL) {
213 		dev_err(&pdev->dev, "platform_get_resource failed\n");
214 		return -ENODEV;
215 	}
216 
217 	data->reg_base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
218 	if (data->reg_base == NULL) {
219 		dev_err(&pdev->dev, "unable to remap MMIO\n");
220 		return -ENOMEM;
221 	}
222 
223 	data->irq = platform_get_irq(pdev, 0);
224 	if (data->irq < 0) {
225 		dev_err(&pdev->dev, "platform_get_irq failed\n");
226 		return -ENODEV;
227 	}
228 
229 	ret = devm_request_irq(&pdev->dev, data->irq,
230 			       goldfish_battery_interrupt,
231 			       IRQF_SHARED, pdev->name, data);
232 	if (ret)
233 		return ret;
234 
235 	psy_cfg.drv_data = data;
236 
237 	data->ac = power_supply_register(&pdev->dev, &ac_desc, &psy_cfg);
238 	if (IS_ERR(data->ac))
239 		return PTR_ERR(data->ac);
240 
241 	data->battery = power_supply_register(&pdev->dev, &battery_desc,
242 						&psy_cfg);
243 	if (IS_ERR(data->battery)) {
244 		power_supply_unregister(data->ac);
245 		return PTR_ERR(data->battery);
246 	}
247 
248 	platform_set_drvdata(pdev, data);
249 
250 	GOLDFISH_BATTERY_WRITE(data, BATTERY_INT_ENABLE, BATTERY_INT_MASK);
251 	return 0;
252 }
253 
254 static int goldfish_battery_remove(struct platform_device *pdev)
255 {
256 	struct goldfish_battery_data *data = platform_get_drvdata(pdev);
257 
258 	power_supply_unregister(data->battery);
259 	power_supply_unregister(data->ac);
260 	return 0;
261 }
262 
263 static const struct of_device_id goldfish_battery_of_match[] = {
264 	{ .compatible = "google,goldfish-battery", },
265 	{},
266 };
267 MODULE_DEVICE_TABLE(of, goldfish_battery_of_match);
268 
269 #ifdef CONFIG_ACPI
270 static const struct acpi_device_id goldfish_battery_acpi_match[] = {
271 	{ "GFSH0001", 0 },
272 	{ },
273 };
274 MODULE_DEVICE_TABLE(acpi, goldfish_battery_acpi_match);
275 #endif
276 
277 static struct platform_driver goldfish_battery_device = {
278 	.probe		= goldfish_battery_probe,
279 	.remove		= goldfish_battery_remove,
280 	.driver = {
281 		.name = "goldfish-battery",
282 		.of_match_table = goldfish_battery_of_match,
283 		.acpi_match_table = ACPI_PTR(goldfish_battery_acpi_match),
284 	}
285 };
286 module_platform_driver(goldfish_battery_device);
287 
288 MODULE_AUTHOR("Mike Lockwood lockwood@android.com");
289 MODULE_LICENSE("GPL");
290 MODULE_DESCRIPTION("Battery driver for the Goldfish emulator");
291