1/*
2 * Power supply driver for the goldfish emulator
3 *
4 * Copyright (C) 2008 Google, Inc.
5 * Copyright (C) 2012 Intel, Inc.
6 * Copyright (C) 2013 Intel, Inc.
7 * Author: Mike Lockwood <lockwood@android.com>
8 *
9 * This software is licensed under the terms of the GNU General Public
10 * License version 2, as published by the Free Software Foundation, and
11 * may be copied, distributed, and modified under those terms.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 */
18
19#include <linux/module.h>
20#include <linux/err.h>
21#include <linux/platform_device.h>
22#include <linux/power_supply.h>
23#include <linux/types.h>
24#include <linux/pci.h>
25#include <linux/interrupt.h>
26#include <linux/io.h>
27
28struct goldfish_battery_data {
29	void __iomem *reg_base;
30	int irq;
31	spinlock_t lock;
32
33	struct power_supply *battery;
34	struct power_supply *ac;
35};
36
37#define GOLDFISH_BATTERY_READ(data, addr) \
38	(readl(data->reg_base + addr))
39#define GOLDFISH_BATTERY_WRITE(data, addr, x) \
40	(writel(x, data->reg_base + addr))
41
42/*
43 * Temporary variable used between goldfish_battery_probe() and
44 * goldfish_battery_open().
45 */
46static struct goldfish_battery_data *battery_data;
47
48enum {
49	/* status register */
50	BATTERY_INT_STATUS	    = 0x00,
51	/* set this to enable IRQ */
52	BATTERY_INT_ENABLE	    = 0x04,
53
54	BATTERY_AC_ONLINE       = 0x08,
55	BATTERY_STATUS          = 0x0C,
56	BATTERY_HEALTH          = 0x10,
57	BATTERY_PRESENT         = 0x14,
58	BATTERY_CAPACITY        = 0x18,
59
60	BATTERY_STATUS_CHANGED	= 1U << 0,
61	AC_STATUS_CHANGED	= 1U << 1,
62	BATTERY_INT_MASK        = BATTERY_STATUS_CHANGED | AC_STATUS_CHANGED,
63};
64
65
66static int goldfish_ac_get_property(struct power_supply *psy,
67			enum power_supply_property psp,
68			union power_supply_propval *val)
69{
70	struct goldfish_battery_data *data = power_supply_get_drvdata(psy);
71	int ret = 0;
72
73	switch (psp) {
74	case POWER_SUPPLY_PROP_ONLINE:
75		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_AC_ONLINE);
76		break;
77	default:
78		ret = -EINVAL;
79		break;
80	}
81	return ret;
82}
83
84static int goldfish_battery_get_property(struct power_supply *psy,
85				 enum power_supply_property psp,
86				 union power_supply_propval *val)
87{
88	struct goldfish_battery_data *data = power_supply_get_drvdata(psy);
89	int ret = 0;
90
91	switch (psp) {
92	case POWER_SUPPLY_PROP_STATUS:
93		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_STATUS);
94		break;
95	case POWER_SUPPLY_PROP_HEALTH:
96		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_HEALTH);
97		break;
98	case POWER_SUPPLY_PROP_PRESENT:
99		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_PRESENT);
100		break;
101	case POWER_SUPPLY_PROP_TECHNOLOGY:
102		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
103		break;
104	case POWER_SUPPLY_PROP_CAPACITY:
105		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_CAPACITY);
106		break;
107	default:
108		ret = -EINVAL;
109		break;
110	}
111
112	return ret;
113}
114
115static enum power_supply_property goldfish_battery_props[] = {
116	POWER_SUPPLY_PROP_STATUS,
117	POWER_SUPPLY_PROP_HEALTH,
118	POWER_SUPPLY_PROP_PRESENT,
119	POWER_SUPPLY_PROP_TECHNOLOGY,
120	POWER_SUPPLY_PROP_CAPACITY,
121};
122
123static enum power_supply_property goldfish_ac_props[] = {
124	POWER_SUPPLY_PROP_ONLINE,
125};
126
127static irqreturn_t goldfish_battery_interrupt(int irq, void *dev_id)
128{
129	unsigned long irq_flags;
130	struct goldfish_battery_data *data = dev_id;
131	uint32_t status;
132
133	spin_lock_irqsave(&data->lock, irq_flags);
134
135	/* read status flags, which will clear the interrupt */
136	status = GOLDFISH_BATTERY_READ(data, BATTERY_INT_STATUS);
137	status &= BATTERY_INT_MASK;
138
139	if (status & BATTERY_STATUS_CHANGED)
140		power_supply_changed(data->battery);
141	if (status & AC_STATUS_CHANGED)
142		power_supply_changed(data->ac);
143
144	spin_unlock_irqrestore(&data->lock, irq_flags);
145	return status ? IRQ_HANDLED : IRQ_NONE;
146}
147
148static const struct power_supply_desc battery_desc = {
149	.properties	= goldfish_battery_props,
150	.num_properties	= ARRAY_SIZE(goldfish_battery_props),
151	.get_property	= goldfish_battery_get_property,
152	.name		= "battery",
153	.type		= POWER_SUPPLY_TYPE_BATTERY,
154};
155
156static const struct power_supply_desc ac_desc = {
157	.properties	= goldfish_ac_props,
158	.num_properties	= ARRAY_SIZE(goldfish_ac_props),
159	.get_property	= goldfish_ac_get_property,
160	.name		= "ac",
161	.type		= POWER_SUPPLY_TYPE_MAINS,
162};
163
164static int goldfish_battery_probe(struct platform_device *pdev)
165{
166	int ret;
167	struct resource *r;
168	struct goldfish_battery_data *data;
169	struct power_supply_config psy_cfg = {};
170
171	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
172	if (data == NULL)
173		return -ENOMEM;
174
175	spin_lock_init(&data->lock);
176
177	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
178	if (r == NULL) {
179		dev_err(&pdev->dev, "platform_get_resource failed\n");
180		return -ENODEV;
181	}
182
183	data->reg_base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
184	if (data->reg_base == NULL) {
185		dev_err(&pdev->dev, "unable to remap MMIO\n");
186		return -ENOMEM;
187	}
188
189	data->irq = platform_get_irq(pdev, 0);
190	if (data->irq < 0) {
191		dev_err(&pdev->dev, "platform_get_irq failed\n");
192		return -ENODEV;
193	}
194
195	ret = devm_request_irq(&pdev->dev, data->irq, goldfish_battery_interrupt,
196						IRQF_SHARED, pdev->name, data);
197	if (ret)
198		return ret;
199
200	psy_cfg.drv_data = data;
201
202	data->ac = power_supply_register(&pdev->dev, &ac_desc, &psy_cfg);
203	if (IS_ERR(data->ac))
204		return PTR_ERR(data->ac);
205
206	data->battery = power_supply_register(&pdev->dev, &battery_desc,
207						&psy_cfg);
208	if (IS_ERR(data->battery)) {
209		power_supply_unregister(data->ac);
210		return PTR_ERR(data->battery);
211	}
212
213	platform_set_drvdata(pdev, data);
214	battery_data = data;
215
216	GOLDFISH_BATTERY_WRITE(data, BATTERY_INT_ENABLE, BATTERY_INT_MASK);
217	return 0;
218}
219
220static int goldfish_battery_remove(struct platform_device *pdev)
221{
222	struct goldfish_battery_data *data = platform_get_drvdata(pdev);
223
224	power_supply_unregister(data->battery);
225	power_supply_unregister(data->ac);
226	battery_data = NULL;
227	return 0;
228}
229
230static struct platform_driver goldfish_battery_device = {
231	.probe		= goldfish_battery_probe,
232	.remove		= goldfish_battery_remove,
233	.driver = {
234		.name = "goldfish-battery"
235	}
236};
237module_platform_driver(goldfish_battery_device);
238
239MODULE_AUTHOR("Mike Lockwood lockwood@android.com");
240MODULE_LICENSE("GPL");
241MODULE_DESCRIPTION("Battery driver for the Goldfish emulator");
242