1 /*
2  * BQ27xxx battery monitor I2C driver
3  *
4  * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/
5  *	Andrew F. Davis <afd@ti.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 version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
12  * kind, whether express or implied; without even the implied warranty
13  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/i2c.h>
18 #include <linux/interrupt.h>
19 #include <linux/module.h>
20 #include <asm/unaligned.h>
21 
22 #include <linux/power/bq27xxx_battery.h>
23 
24 static DEFINE_IDR(battery_id);
25 static DEFINE_MUTEX(battery_mutex);
26 
27 static irqreturn_t bq27xxx_battery_irq_handler_thread(int irq, void *data)
28 {
29 	struct bq27xxx_device_info *di = data;
30 
31 	bq27xxx_battery_update(di);
32 
33 	return IRQ_HANDLED;
34 }
35 
36 static int bq27xxx_battery_i2c_read(struct bq27xxx_device_info *di, u8 reg,
37 				    bool single)
38 {
39 	struct i2c_client *client = to_i2c_client(di->dev);
40 	struct i2c_msg msg[2];
41 	unsigned char data[2];
42 	int ret;
43 
44 	if (!client->adapter)
45 		return -ENODEV;
46 
47 	msg[0].addr = client->addr;
48 	msg[0].flags = 0;
49 	msg[0].buf = &reg;
50 	msg[0].len = sizeof(reg);
51 	msg[1].addr = client->addr;
52 	msg[1].flags = I2C_M_RD;
53 	msg[1].buf = data;
54 	if (single)
55 		msg[1].len = 1;
56 	else
57 		msg[1].len = 2;
58 
59 	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
60 	if (ret < 0)
61 		return ret;
62 
63 	if (!single)
64 		ret = get_unaligned_le16(data);
65 	else
66 		ret = data[0];
67 
68 	return ret;
69 }
70 
71 static int bq27xxx_battery_i2c_probe(struct i2c_client *client,
72 				     const struct i2c_device_id *id)
73 {
74 	struct bq27xxx_device_info *di;
75 	int ret;
76 	char *name;
77 	int num;
78 
79 	/* Get new ID for the new battery device */
80 	mutex_lock(&battery_mutex);
81 	num = idr_alloc(&battery_id, client, 0, 0, GFP_KERNEL);
82 	mutex_unlock(&battery_mutex);
83 	if (num < 0)
84 		return num;
85 
86 	name = devm_kasprintf(&client->dev, GFP_KERNEL, "%s-%d", id->name, num);
87 	if (!name)
88 		goto err_mem;
89 
90 	di = devm_kzalloc(&client->dev, sizeof(*di), GFP_KERNEL);
91 	if (!di)
92 		goto err_mem;
93 
94 	di->id = num;
95 	di->dev = &client->dev;
96 	di->chip = id->driver_data;
97 	di->name = name;
98 	di->bus.read = bq27xxx_battery_i2c_read;
99 
100 	ret = bq27xxx_battery_setup(di);
101 	if (ret)
102 		goto err_failed;
103 
104 	/* Schedule a polling after about 1 min */
105 	schedule_delayed_work(&di->work, 60 * HZ);
106 
107 	i2c_set_clientdata(client, di);
108 
109 	if (client->irq) {
110 		ret = devm_request_threaded_irq(&client->dev, client->irq,
111 				NULL, bq27xxx_battery_irq_handler_thread,
112 				IRQF_ONESHOT,
113 				di->name, di);
114 		if (ret) {
115 			dev_err(&client->dev,
116 				"Unable to register IRQ %d error %d\n",
117 				client->irq, ret);
118 			return ret;
119 		}
120 	}
121 
122 	return 0;
123 
124 err_mem:
125 	ret = -ENOMEM;
126 
127 err_failed:
128 	mutex_lock(&battery_mutex);
129 	idr_remove(&battery_id, num);
130 	mutex_unlock(&battery_mutex);
131 
132 	return ret;
133 }
134 
135 static int bq27xxx_battery_i2c_remove(struct i2c_client *client)
136 {
137 	struct bq27xxx_device_info *di = i2c_get_clientdata(client);
138 
139 	bq27xxx_battery_teardown(di);
140 
141 	mutex_lock(&battery_mutex);
142 	idr_remove(&battery_id, di->id);
143 	mutex_unlock(&battery_mutex);
144 
145 	return 0;
146 }
147 
148 static const struct i2c_device_id bq27xxx_i2c_id_table[] = {
149 	{ "bq27200", BQ27000 },
150 	{ "bq27210", BQ27010 },
151 	{ "bq27500", BQ2750X },
152 	{ "bq27510", BQ2751X },
153 	{ "bq27520", BQ2751X },
154 	{ "bq27500-1", BQ27500 },
155 	{ "bq27510g1", BQ27510G1 },
156 	{ "bq27510g2", BQ27510G2 },
157 	{ "bq27510g3", BQ27510G3 },
158 	{ "bq27520g1", BQ27520G1 },
159 	{ "bq27520g2", BQ27520G2 },
160 	{ "bq27520g3", BQ27520G3 },
161 	{ "bq27520g4", BQ27520G4 },
162 	{ "bq27530", BQ27530 },
163 	{ "bq27531", BQ27530 },
164 	{ "bq27541", BQ27541 },
165 	{ "bq27542", BQ27541 },
166 	{ "bq27546", BQ27541 },
167 	{ "bq27742", BQ27541 },
168 	{ "bq27545", BQ27545 },
169 	{ "bq27421", BQ27421 },
170 	{ "bq27425", BQ27421 },
171 	{ "bq27441", BQ27421 },
172 	{ "bq27621", BQ27421 },
173 	{},
174 };
175 MODULE_DEVICE_TABLE(i2c, bq27xxx_i2c_id_table);
176 
177 #ifdef CONFIG_OF
178 static const struct of_device_id bq27xxx_battery_i2c_of_match_table[] = {
179 	{ .compatible = "ti,bq27200" },
180 	{ .compatible = "ti,bq27210" },
181 	{ .compatible = "ti,bq27500" },
182 	{ .compatible = "ti,bq27510" },
183 	{ .compatible = "ti,bq27520" },
184 	{ .compatible = "ti,bq27500-1" },
185 	{ .compatible = "ti,bq27510g1" },
186 	{ .compatible = "ti,bq27510g2" },
187 	{ .compatible = "ti,bq27510g3" },
188 	{ .compatible = "ti,bq27520g1" },
189 	{ .compatible = "ti,bq27520g2" },
190 	{ .compatible = "ti,bq27520g3" },
191 	{ .compatible = "ti,bq27520g4" },
192 	{ .compatible = "ti,bq27530" },
193 	{ .compatible = "ti,bq27531" },
194 	{ .compatible = "ti,bq27541" },
195 	{ .compatible = "ti,bq27542" },
196 	{ .compatible = "ti,bq27546" },
197 	{ .compatible = "ti,bq27742" },
198 	{ .compatible = "ti,bq27545" },
199 	{ .compatible = "ti,bq27421" },
200 	{ .compatible = "ti,bq27425" },
201 	{ .compatible = "ti,bq27441" },
202 	{ .compatible = "ti,bq27621" },
203 	{},
204 };
205 MODULE_DEVICE_TABLE(of, bq27xxx_battery_i2c_of_match_table);
206 #endif
207 
208 static struct i2c_driver bq27xxx_battery_i2c_driver = {
209 	.driver = {
210 		.name = "bq27xxx-battery",
211 		.of_match_table = of_match_ptr(bq27xxx_battery_i2c_of_match_table),
212 	},
213 	.probe = bq27xxx_battery_i2c_probe,
214 	.remove = bq27xxx_battery_i2c_remove,
215 	.id_table = bq27xxx_i2c_id_table,
216 };
217 module_i2c_driver(bq27xxx_battery_i2c_driver);
218 
219 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
220 MODULE_DESCRIPTION("BQ27xxx battery monitor i2c driver");
221 MODULE_LICENSE("GPL");
222