1 /*
2  * Copyright (C) 2007 Texas Instruments, Inc.
3  *
4  * This file is licensed under the terms of the GNU General Public License
5  * version 2. This program is licensed "as is" without any warranty of any
6  * kind, whether express or implied.
7  *
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/device.h>
13 #include <linux/types.h>
14 #include <linux/platform_device.h>
15 #include <linux/mutex.h>
16 #include <linux/power/bq27xxx_battery.h>
17 
18 #include <linux/w1.h>
19 
20 #define W1_FAMILY_BQ27000	0x01
21 
22 #define HDQ_CMD_READ	(0)
23 #define HDQ_CMD_WRITE	(1<<7)
24 
25 static int F_ID;
26 module_param(F_ID, int, S_IRUSR);
27 MODULE_PARM_DESC(F_ID, "1-wire slave FID for BQ device");
28 
29 static int w1_bq27000_read(struct device *dev, unsigned int reg)
30 {
31 	u8 val;
32 	struct w1_slave *sl = container_of(dev->parent, struct w1_slave, dev);
33 
34 	mutex_lock(&sl->master->bus_mutex);
35 	w1_write_8(sl->master, HDQ_CMD_READ | reg);
36 	val = w1_read_8(sl->master);
37 	mutex_unlock(&sl->master->bus_mutex);
38 
39 	return val;
40 }
41 
42 static struct bq27xxx_platform_data bq27000_battery_info = {
43 	.read   = w1_bq27000_read,
44 	.name   = "bq27000-battery",
45 	.chip   = BQ27000,
46 };
47 
48 static int w1_bq27000_add_slave(struct w1_slave *sl)
49 {
50 	int ret;
51 	struct platform_device *pdev;
52 
53 	pdev = platform_device_alloc("bq27000-battery", -1);
54 	if (!pdev) {
55 		ret = -ENOMEM;
56 		return ret;
57 	}
58 	ret = platform_device_add_data(pdev,
59 				       &bq27000_battery_info,
60 				       sizeof(bq27000_battery_info));
61 	if (ret)
62 		goto pdev_add_failed;
63 	pdev->dev.parent = &sl->dev;
64 
65 	ret = platform_device_add(pdev);
66 	if (ret)
67 		goto pdev_add_failed;
68 
69 	dev_set_drvdata(&sl->dev, pdev);
70 
71 	goto success;
72 
73 pdev_add_failed:
74 	platform_device_put(pdev);
75 success:
76 	return ret;
77 }
78 
79 static void w1_bq27000_remove_slave(struct w1_slave *sl)
80 {
81 	struct platform_device *pdev = dev_get_drvdata(&sl->dev);
82 
83 	platform_device_unregister(pdev);
84 }
85 
86 static struct w1_family_ops w1_bq27000_fops = {
87 	.add_slave	= w1_bq27000_add_slave,
88 	.remove_slave	= w1_bq27000_remove_slave,
89 };
90 
91 static struct w1_family w1_bq27000_family = {
92 	.fid = W1_FAMILY_BQ27000,
93 	.fops = &w1_bq27000_fops,
94 };
95 
96 static int __init w1_bq27000_init(void)
97 {
98 	if (F_ID)
99 		w1_bq27000_family.fid = F_ID;
100 
101 	return w1_register_family(&w1_bq27000_family);
102 }
103 
104 static void __exit w1_bq27000_exit(void)
105 {
106 	w1_unregister_family(&w1_bq27000_family);
107 }
108 
109 module_init(w1_bq27000_init);
110 module_exit(w1_bq27000_exit);
111 
112 MODULE_AUTHOR("Texas Instruments Ltd");
113 MODULE_DESCRIPTION("HDQ/1-wire slave driver bq27000 battery monitor chip");
114 MODULE_LICENSE("GPL");
115 MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_BQ27000));
116