blob: d00a274df8fcedf76d00d52d668493e9e9e068cf [file] [log] [blame]
David S. Millercca4c232008-08-29 01:29:53 -07001/* rtc-bq4802.c: TI BQ4802 RTC driver.
2 *
3 * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
4 */
5
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
14MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
15MODULE_DESCRIPTION("TI BQ4802 RTC driver");
16MODULE_LICENSE("GPL");
17
18struct bq4802 {
19 void __iomem *regs;
David S. Miller503acc82008-09-09 19:50:04 -070020 unsigned long ioport;
David S. Millercca4c232008-08-29 01:29:53 -070021 struct rtc_device *rtc;
22 spinlock_t lock;
23 struct resource *r;
24 u8 (*read)(struct bq4802 *, int);
25 void (*write)(struct bq4802 *, int, u8);
26};
27
28static u8 bq4802_read_io(struct bq4802 *p, int off)
29{
David S. Miller503acc82008-09-09 19:50:04 -070030 return inb(p->ioport + off);
David S. Millercca4c232008-08-29 01:29:53 -070031}
32
33static void bq4802_write_io(struct bq4802 *p, int off, u8 val)
34{
David S. Miller503acc82008-09-09 19:50:04 -070035 outb(val, p->ioport + off);
David S. Millercca4c232008-08-29 01:29:53 -070036}
37
38static u8 bq4802_read_mem(struct bq4802 *p, int off)
39{
40 return readb(p->regs + off);
41}
42
43static void bq4802_write_mem(struct bq4802 *p, int off, u8 val)
44{
David S. Miller503acc82008-09-09 19:50:04 -070045 writeb(val, p->regs + off);
David S. Millercca4c232008-08-29 01:29:53 -070046}
47
48static int bq4802_read_time(struct device *dev, struct rtc_time *tm)
49{
50 struct platform_device *pdev = to_platform_device(dev);
51 struct bq4802 *p = platform_get_drvdata(pdev);
52 unsigned long flags;
53 unsigned int century;
54 u8 val;
55
56 spin_lock_irqsave(&p->lock, flags);
57
58 val = p->read(p, 0x0e);
59 p->write(p, 0xe, val | 0x08);
60
61 tm->tm_sec = p->read(p, 0x00);
62 tm->tm_min = p->read(p, 0x02);
63 tm->tm_hour = p->read(p, 0x04);
64 tm->tm_mday = p->read(p, 0x06);
65 tm->tm_mon = p->read(p, 0x09);
66 tm->tm_year = p->read(p, 0x0a);
67 tm->tm_wday = p->read(p, 0x08);
68 century = p->read(p, 0x0f);
69
70 p->write(p, 0x0e, val);
71
72 spin_unlock_irqrestore(&p->lock, flags);
73
Andrew Mortone232cfd2008-10-18 20:28:43 -070074 tm->tm_sec = bcd2bin(tm->tm_sec);
75 tm->tm_min = bcd2bin(tm->tm_min);
76 tm->tm_hour = bcd2bin(tm->tm_hour);
77 tm->tm_mday = bcd2bin(tm->tm_mday);
78 tm->tm_mon = bcd2bin(tm->tm_mon);
79 tm->tm_year = bcd2bin(tm->tm_year);
80 tm->tm_wday = bcd2bin(tm->tm_wday);
81 century = bcd2bin(century);
David S. Millercca4c232008-08-29 01:29:53 -070082
83 tm->tm_year += (century * 100);
84 tm->tm_year -= 1900;
85
86 tm->tm_mon--;
87
88 return 0;
89}
90
91static int bq4802_set_time(struct device *dev, struct rtc_time *tm)
92{
93 struct platform_device *pdev = to_platform_device(dev);
94 struct bq4802 *p = platform_get_drvdata(pdev);
95 u8 sec, min, hrs, day, mon, yrs, century, val;
96 unsigned long flags;
97 unsigned int year;
98
99 year = tm->tm_year + 1900;
100 century = year / 100;
101 yrs = year % 100;
102
103 mon = tm->tm_mon + 1; /* tm_mon starts at zero */
104 day = tm->tm_mday;
105 hrs = tm->tm_hour;
106 min = tm->tm_min;
107 sec = tm->tm_sec;
108
Andrew Mortone232cfd2008-10-18 20:28:43 -0700109 sec = bin2bcd(sec);
110 min = bin2bcd(min);
111 hrs = bin2bcd(hrs);
112 day = bin2bcd(day);
113 mon = bin2bcd(mon);
114 yrs = bin2bcd(yrs);
115 century = bin2bcd(century);
David S. Millercca4c232008-08-29 01:29:53 -0700116
117 spin_lock_irqsave(&p->lock, flags);
118
119 val = p->read(p, 0x0e);
120 p->write(p, 0x0e, val | 0x08);
121
122 p->write(p, 0x00, sec);
123 p->write(p, 0x02, min);
124 p->write(p, 0x04, hrs);
125 p->write(p, 0x06, day);
126 p->write(p, 0x09, mon);
127 p->write(p, 0x0a, yrs);
128 p->write(p, 0x0f, century);
129
130 p->write(p, 0x0e, val);
131
132 spin_unlock_irqrestore(&p->lock, flags);
133
134 return 0;
135}
136
137static const struct rtc_class_ops bq4802_ops = {
138 .read_time = bq4802_read_time,
139 .set_time = bq4802_set_time,
140};
141
142static int __devinit bq4802_probe(struct platform_device *pdev)
143{
144 struct bq4802 *p = kzalloc(sizeof(*p), GFP_KERNEL);
145 int err = -ENOMEM;
146
147 if (!p)
148 goto out;
149
150 spin_lock_init(&p->lock);
151
152 p->r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
153 if (!p->r) {
154 p->r = platform_get_resource(pdev, IORESOURCE_IO, 0);
155 err = -EINVAL;
156 if (!p->r)
157 goto out_free;
158 }
159 if (p->r->flags & IORESOURCE_IO) {
David S. Miller503acc82008-09-09 19:50:04 -0700160 p->ioport = p->r->start;
David S. Millercca4c232008-08-29 01:29:53 -0700161 p->read = bq4802_read_io;
162 p->write = bq4802_write_io;
163 } else if (p->r->flags & IORESOURCE_MEM) {
164 p->regs = ioremap(p->r->start, resource_size(p->r));
165 p->read = bq4802_read_mem;
166 p->write = bq4802_write_mem;
167 } else {
168 err = -EINVAL;
169 goto out_free;
170 }
171
172 p->rtc = rtc_device_register("bq4802", &pdev->dev,
173 &bq4802_ops, THIS_MODULE);
174 if (IS_ERR(p->rtc)) {
175 err = PTR_ERR(p->rtc);
176 goto out_iounmap;
177 }
178
179 platform_set_drvdata(pdev, p);
180 err = 0;
181out:
182 return err;
183
184out_iounmap:
185 if (p->r->flags & IORESOURCE_MEM)
186 iounmap(p->regs);
187out_free:
188 kfree(p);
189 goto out;
190}
191
192static int __devexit bq4802_remove(struct platform_device *pdev)
193{
194 struct bq4802 *p = platform_get_drvdata(pdev);
195
196 rtc_device_unregister(p->rtc);
197 if (p->r->flags & IORESOURCE_MEM)
198 iounmap(p->regs);
199
200 platform_set_drvdata(pdev, NULL);
201
202 kfree(p);
203
204 return 0;
205}
206
207/* work with hotplug and coldplug */
208MODULE_ALIAS("platform:rtc-bq4802");
209
210static struct platform_driver bq4802_driver = {
211 .driver = {
212 .name = "rtc-bq4802",
213 .owner = THIS_MODULE,
214 },
215 .probe = bq4802_probe,
216 .remove = __devexit_p(bq4802_remove),
217};
218
219static int __init bq4802_init(void)
220{
221 return platform_driver_register(&bq4802_driver);
222}
223
224static void __exit bq4802_exit(void)
225{
226 platform_driver_unregister(&bq4802_driver);
227}
228
229module_init(bq4802_init);
230module_exit(bq4802_exit);