diff options
Diffstat (limited to 'drivers/rtc/rtc-bq4802.c')
-rw-r--r-- | drivers/rtc/rtc-bq4802.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-bq4802.c b/drivers/rtc/rtc-bq4802.c new file mode 100644 index 000000000000..541580cb6df4 --- /dev/null +++ b/drivers/rtc/rtc-bq4802.c | |||
@@ -0,0 +1,229 @@ | |||
1 | /* 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 | |||
14 | MODULE_AUTHOR("David S. Miller <davem@davemloft.net>"); | ||
15 | MODULE_DESCRIPTION("TI BQ4802 RTC driver"); | ||
16 | MODULE_LICENSE("GPL"); | ||
17 | |||
18 | struct bq4802 { | ||
19 | void __iomem *regs; | ||
20 | struct rtc_device *rtc; | ||
21 | spinlock_t lock; | ||
22 | struct resource *r; | ||
23 | u8 (*read)(struct bq4802 *, int); | ||
24 | void (*write)(struct bq4802 *, int, u8); | ||
25 | }; | ||
26 | |||
27 | static u8 bq4802_read_io(struct bq4802 *p, int off) | ||
28 | { | ||
29 | return inb(p->regs + off); | ||
30 | } | ||
31 | |||
32 | static void bq4802_write_io(struct bq4802 *p, int off, u8 val) | ||
33 | { | ||
34 | return outb(val, p->regs + off); | ||
35 | } | ||
36 | |||
37 | static u8 bq4802_read_mem(struct bq4802 *p, int off) | ||
38 | { | ||
39 | return readb(p->regs + off); | ||
40 | } | ||
41 | |||
42 | static void bq4802_write_mem(struct bq4802 *p, int off, u8 val) | ||
43 | { | ||
44 | return writeb(val, p->regs + off); | ||
45 | } | ||
46 | |||
47 | static int bq4802_read_time(struct device *dev, struct rtc_time *tm) | ||
48 | { | ||
49 | struct platform_device *pdev = to_platform_device(dev); | ||
50 | struct bq4802 *p = platform_get_drvdata(pdev); | ||
51 | unsigned long flags; | ||
52 | unsigned int century; | ||
53 | u8 val; | ||
54 | |||
55 | spin_lock_irqsave(&p->lock, flags); | ||
56 | |||
57 | val = p->read(p, 0x0e); | ||
58 | p->write(p, 0xe, val | 0x08); | ||
59 | |||
60 | tm->tm_sec = p->read(p, 0x00); | ||
61 | tm->tm_min = p->read(p, 0x02); | ||
62 | tm->tm_hour = p->read(p, 0x04); | ||
63 | tm->tm_mday = p->read(p, 0x06); | ||
64 | tm->tm_mon = p->read(p, 0x09); | ||
65 | tm->tm_year = p->read(p, 0x0a); | ||
66 | tm->tm_wday = p->read(p, 0x08); | ||
67 | century = p->read(p, 0x0f); | ||
68 | |||
69 | p->write(p, 0x0e, val); | ||
70 | |||
71 | spin_unlock_irqrestore(&p->lock, flags); | ||
72 | |||
73 | BCD_TO_BIN(tm->tm_sec); | ||
74 | BCD_TO_BIN(tm->tm_min); | ||
75 | BCD_TO_BIN(tm->tm_hour); | ||
76 | BCD_TO_BIN(tm->tm_mday); | ||
77 | BCD_TO_BIN(tm->tm_mon); | ||
78 | BCD_TO_BIN(tm->tm_year); | ||
79 | BCD_TO_BIN(tm->tm_wday); | ||
80 | BCD_TO_BIN(century); | ||
81 | |||
82 | tm->tm_year += (century * 100); | ||
83 | tm->tm_year -= 1900; | ||
84 | |||
85 | tm->tm_mon--; | ||
86 | |||
87 | return 0; | ||
88 | } | ||
89 | |||
90 | static int bq4802_set_time(struct device *dev, struct rtc_time *tm) | ||
91 | { | ||
92 | struct platform_device *pdev = to_platform_device(dev); | ||
93 | struct bq4802 *p = platform_get_drvdata(pdev); | ||
94 | u8 sec, min, hrs, day, mon, yrs, century, val; | ||
95 | unsigned long flags; | ||
96 | unsigned int year; | ||
97 | |||
98 | year = tm->tm_year + 1900; | ||
99 | century = year / 100; | ||
100 | yrs = year % 100; | ||
101 | |||
102 | mon = tm->tm_mon + 1; /* tm_mon starts at zero */ | ||
103 | day = tm->tm_mday; | ||
104 | hrs = tm->tm_hour; | ||
105 | min = tm->tm_min; | ||
106 | sec = tm->tm_sec; | ||
107 | |||
108 | BIN_TO_BCD(sec); | ||
109 | BIN_TO_BCD(min); | ||
110 | BIN_TO_BCD(hrs); | ||
111 | BIN_TO_BCD(day); | ||
112 | BIN_TO_BCD(mon); | ||
113 | BIN_TO_BCD(yrs); | ||
114 | BIN_TO_BCD(century); | ||
115 | |||
116 | spin_lock_irqsave(&p->lock, flags); | ||
117 | |||
118 | val = p->read(p, 0x0e); | ||
119 | p->write(p, 0x0e, val | 0x08); | ||
120 | |||
121 | p->write(p, 0x00, sec); | ||
122 | p->write(p, 0x02, min); | ||
123 | p->write(p, 0x04, hrs); | ||
124 | p->write(p, 0x06, day); | ||
125 | p->write(p, 0x09, mon); | ||
126 | p->write(p, 0x0a, yrs); | ||
127 | p->write(p, 0x0f, century); | ||
128 | |||
129 | p->write(p, 0x0e, val); | ||
130 | |||
131 | spin_unlock_irqrestore(&p->lock, flags); | ||
132 | |||
133 | return 0; | ||
134 | } | ||
135 | |||
136 | static const struct rtc_class_ops bq4802_ops = { | ||
137 | .read_time = bq4802_read_time, | ||
138 | .set_time = bq4802_set_time, | ||
139 | }; | ||
140 | |||
141 | static int __devinit bq4802_probe(struct platform_device *pdev) | ||
142 | { | ||
143 | struct bq4802 *p = kzalloc(sizeof(*p), GFP_KERNEL); | ||
144 | int err = -ENOMEM; | ||
145 | |||
146 | if (!p) | ||
147 | goto out; | ||
148 | |||
149 | spin_lock_init(&p->lock); | ||
150 | |||
151 | p->r = platform_get_resource(pdev, IORESOURCE_MEM, 0); | ||
152 | if (!p->r) { | ||
153 | p->r = platform_get_resource(pdev, IORESOURCE_IO, 0); | ||
154 | err = -EINVAL; | ||
155 | if (!p->r) | ||
156 | goto out_free; | ||
157 | } | ||
158 | if (p->r->flags & IORESOURCE_IO) { | ||
159 | p->regs = (void __iomem *) p->r->start; | ||
160 | p->read = bq4802_read_io; | ||
161 | p->write = bq4802_write_io; | ||
162 | } else if (p->r->flags & IORESOURCE_MEM) { | ||
163 | p->regs = ioremap(p->r->start, resource_size(p->r)); | ||
164 | p->read = bq4802_read_mem; | ||
165 | p->write = bq4802_write_mem; | ||
166 | } else { | ||
167 | err = -EINVAL; | ||
168 | goto out_free; | ||
169 | } | ||
170 | |||
171 | p->rtc = rtc_device_register("bq4802", &pdev->dev, | ||
172 | &bq4802_ops, THIS_MODULE); | ||
173 | if (IS_ERR(p->rtc)) { | ||
174 | err = PTR_ERR(p->rtc); | ||
175 | goto out_iounmap; | ||
176 | } | ||
177 | |||
178 | platform_set_drvdata(pdev, p); | ||
179 | err = 0; | ||
180 | out: | ||
181 | return err; | ||
182 | |||
183 | out_iounmap: | ||
184 | if (p->r->flags & IORESOURCE_MEM) | ||
185 | iounmap(p->regs); | ||
186 | out_free: | ||
187 | kfree(p); | ||
188 | goto out; | ||
189 | } | ||
190 | |||
191 | static int __devexit bq4802_remove(struct platform_device *pdev) | ||
192 | { | ||
193 | struct bq4802 *p = platform_get_drvdata(pdev); | ||
194 | |||
195 | rtc_device_unregister(p->rtc); | ||
196 | if (p->r->flags & IORESOURCE_MEM) | ||
197 | iounmap(p->regs); | ||
198 | |||
199 | platform_set_drvdata(pdev, NULL); | ||
200 | |||
201 | kfree(p); | ||
202 | |||
203 | return 0; | ||
204 | } | ||
205 | |||
206 | /* work with hotplug and coldplug */ | ||
207 | MODULE_ALIAS("platform:rtc-bq4802"); | ||
208 | |||
209 | static struct platform_driver bq4802_driver = { | ||
210 | .driver = { | ||
211 | .name = "rtc-bq4802", | ||
212 | .owner = THIS_MODULE, | ||
213 | }, | ||
214 | .probe = bq4802_probe, | ||
215 | .remove = __devexit_p(bq4802_remove), | ||
216 | }; | ||
217 | |||
218 | static int __init bq4802_init(void) | ||
219 | { | ||
220 | return platform_driver_register(&bq4802_driver); | ||
221 | } | ||
222 | |||
223 | static void __exit bq4802_exit(void) | ||
224 | { | ||
225 | platform_driver_unregister(&bq4802_driver); | ||
226 | } | ||
227 | |||
228 | module_init(bq4802_init); | ||
229 | module_exit(bq4802_exit); | ||