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6#include <linux/kernel.h>
7#include <linux/module.h>
8#include <linux/init.h>
9#include <linux/io.h>
10#include <linux/platform_device.h>
11#include <linux/rtc.h>
12#include <linux/bcd.h>
13#include <linux/slab.h>
14
15MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
16MODULE_DESCRIPTION("TI BQ4802 RTC driver");
17MODULE_LICENSE("GPL");
18
19struct bq4802 {
20 void __iomem *regs;
21 unsigned long ioport;
22 struct rtc_device *rtc;
23 spinlock_t lock;
24 struct resource *r;
25 u8 (*read)(struct bq4802 *, int);
26 void (*write)(struct bq4802 *, int, u8);
27};
28
29static u8 bq4802_read_io(struct bq4802 *p, int off)
30{
31 return inb(p->ioport + off);
32}
33
34static void bq4802_write_io(struct bq4802 *p, int off, u8 val)
35{
36 outb(val, p->ioport + off);
37}
38
39static u8 bq4802_read_mem(struct bq4802 *p, int off)
40{
41 return readb(p->regs + off);
42}
43
44static void bq4802_write_mem(struct bq4802 *p, int off, u8 val)
45{
46 writeb(val, p->regs + off);
47}
48
49static int bq4802_read_time(struct device *dev, struct rtc_time *tm)
50{
51 struct platform_device *pdev = to_platform_device(dev);
52 struct bq4802 *p = platform_get_drvdata(pdev);
53 unsigned long flags;
54 unsigned int century;
55 u8 val;
56
57 spin_lock_irqsave(&p->lock, flags);
58
59 val = p->read(p, 0x0e);
60 p->write(p, 0xe, val | 0x08);
61
62 tm->tm_sec = p->read(p, 0x00);
63 tm->tm_min = p->read(p, 0x02);
64 tm->tm_hour = p->read(p, 0x04);
65 tm->tm_mday = p->read(p, 0x06);
66 tm->tm_mon = p->read(p, 0x09);
67 tm->tm_year = p->read(p, 0x0a);
68 tm->tm_wday = p->read(p, 0x08);
69 century = p->read(p, 0x0f);
70
71 p->write(p, 0x0e, val);
72
73 spin_unlock_irqrestore(&p->lock, flags);
74
75 tm->tm_sec = bcd2bin(tm->tm_sec);
76 tm->tm_min = bcd2bin(tm->tm_min);
77 tm->tm_hour = bcd2bin(tm->tm_hour);
78 tm->tm_mday = bcd2bin(tm->tm_mday);
79 tm->tm_mon = bcd2bin(tm->tm_mon);
80 tm->tm_year = bcd2bin(tm->tm_year);
81 tm->tm_wday = bcd2bin(tm->tm_wday);
82 century = bcd2bin(century);
83
84 tm->tm_year += (century * 100);
85 tm->tm_year -= 1900;
86
87 tm->tm_mon--;
88
89 return 0;
90}
91
92static int bq4802_set_time(struct device *dev, struct rtc_time *tm)
93{
94 struct platform_device *pdev = to_platform_device(dev);
95 struct bq4802 *p = platform_get_drvdata(pdev);
96 u8 sec, min, hrs, day, mon, yrs, century, val;
97 unsigned long flags;
98 unsigned int year;
99
100 year = tm->tm_year + 1900;
101 century = year / 100;
102 yrs = year % 100;
103
104 mon = tm->tm_mon + 1;
105 day = tm->tm_mday;
106 hrs = tm->tm_hour;
107 min = tm->tm_min;
108 sec = tm->tm_sec;
109
110 sec = bin2bcd(sec);
111 min = bin2bcd(min);
112 hrs = bin2bcd(hrs);
113 day = bin2bcd(day);
114 mon = bin2bcd(mon);
115 yrs = bin2bcd(yrs);
116 century = bin2bcd(century);
117
118 spin_lock_irqsave(&p->lock, flags);
119
120 val = p->read(p, 0x0e);
121 p->write(p, 0x0e, val | 0x08);
122
123 p->write(p, 0x00, sec);
124 p->write(p, 0x02, min);
125 p->write(p, 0x04, hrs);
126 p->write(p, 0x06, day);
127 p->write(p, 0x09, mon);
128 p->write(p, 0x0a, yrs);
129 p->write(p, 0x0f, century);
130
131 p->write(p, 0x0e, val);
132
133 spin_unlock_irqrestore(&p->lock, flags);
134
135 return 0;
136}
137
138static const struct rtc_class_ops bq4802_ops = {
139 .read_time = bq4802_read_time,
140 .set_time = bq4802_set_time,
141};
142
143static int bq4802_probe(struct platform_device *pdev)
144{
145 struct bq4802 *p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
146 int err = -ENOMEM;
147
148 if (!p)
149 goto out;
150
151 spin_lock_init(&p->lock);
152
153 p->r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
154 if (!p->r) {
155 p->r = platform_get_resource(pdev, IORESOURCE_IO, 0);
156 err = -EINVAL;
157 if (!p->r)
158 goto out;
159 }
160 if (p->r->flags & IORESOURCE_IO) {
161 p->ioport = p->r->start;
162 p->read = bq4802_read_io;
163 p->write = bq4802_write_io;
164 } else if (p->r->flags & IORESOURCE_MEM) {
165 p->regs = devm_ioremap(&pdev->dev, p->r->start,
166 resource_size(p->r));
167 p->read = bq4802_read_mem;
168 p->write = bq4802_write_mem;
169 } else {
170 err = -EINVAL;
171 goto out;
172 }
173
174 platform_set_drvdata(pdev, p);
175
176 p->rtc = devm_rtc_device_register(&pdev->dev, "bq4802",
177 &bq4802_ops, THIS_MODULE);
178 if (IS_ERR(p->rtc)) {
179 err = PTR_ERR(p->rtc);
180 goto out;
181 }
182
183 err = 0;
184out:
185 return err;
186
187}
188
189
190MODULE_ALIAS("platform:rtc-bq4802");
191
192static struct platform_driver bq4802_driver = {
193 .driver = {
194 .name = "rtc-bq4802",
195 .owner = THIS_MODULE,
196 },
197 .probe = bq4802_probe,
198};
199
200module_platform_driver(bq4802_driver);
201
