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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/sbus/char/rtc.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/sbus/char/rtc.c')
-rw-r--r--drivers/sbus/char/rtc.c178
1 files changed, 178 insertions, 0 deletions
diff --git a/drivers/sbus/char/rtc.c b/drivers/sbus/char/rtc.c
new file mode 100644
index 000000000000..bf3273eb1c8b
--- /dev/null
+++ b/drivers/sbus/char/rtc.c
@@ -0,0 +1,178 @@
1/* $Id: rtc.c,v 1.28 2001/10/08 22:19:51 davem Exp $
2 *
3 * Linux/SPARC Real Time Clock Driver
4 * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
5 *
6 * This is a little driver that lets a user-level program access
7 * the SPARC Mostek real time clock chip. It is no use unless you
8 * use the modified clock utility.
9 *
10 * Get the modified clock utility from:
11 * ftp://vger.kernel.org/pub/linux/Sparc/userland/clock.c
12 */
13
14#include <linux/module.h>
15#include <linux/types.h>
16#include <linux/errno.h>
17#include <linux/miscdevice.h>
18#include <linux/slab.h>
19#include <linux/fcntl.h>
20#include <linux/poll.h>
21#include <linux/init.h>
22#include <linux/smp_lock.h>
23#include <asm/io.h>
24#include <asm/mostek.h>
25#include <asm/system.h>
26#include <asm/uaccess.h>
27#include <asm/rtc.h>
28
29static int rtc_busy = 0;
30
31/* Retrieve the current date and time from the real time clock. */
32static void get_rtc_time(struct rtc_time *t)
33{
34 void * __iomem regs = mstk48t02_regs;
35 u8 tmp;
36
37 spin_lock_irq(&mostek_lock);
38
39 tmp = mostek_read(regs + MOSTEK_CREG);
40 tmp |= MSTK_CREG_READ;
41 mostek_write(regs + MOSTEK_CREG, tmp);
42
43 t->sec = MSTK_REG_SEC(regs);
44 t->min = MSTK_REG_MIN(regs);
45 t->hour = MSTK_REG_HOUR(regs);
46 t->dow = MSTK_REG_DOW(regs);
47 t->dom = MSTK_REG_DOM(regs);
48 t->month = MSTK_REG_MONTH(regs);
49 t->year = MSTK_CVT_YEAR( MSTK_REG_YEAR(regs) );
50
51 tmp = mostek_read(regs + MOSTEK_CREG);
52 tmp &= ~MSTK_CREG_READ;
53 mostek_write(regs + MOSTEK_CREG, tmp);
54
55 spin_unlock_irq(&mostek_lock);
56}
57
58/* Set the current date and time inthe real time clock. */
59void set_rtc_time(struct rtc_time *t)
60{
61 void * __iomem regs = mstk48t02_regs;
62 u8 tmp;
63
64 spin_lock_irq(&mostek_lock);
65
66 tmp = mostek_read(regs + MOSTEK_CREG);
67 tmp |= MSTK_CREG_WRITE;
68 mostek_write(regs + MOSTEK_CREG, tmp);
69
70 MSTK_SET_REG_SEC(regs,t->sec);
71 MSTK_SET_REG_MIN(regs,t->min);
72 MSTK_SET_REG_HOUR(regs,t->hour);
73 MSTK_SET_REG_DOW(regs,t->dow);
74 MSTK_SET_REG_DOM(regs,t->dom);
75 MSTK_SET_REG_MONTH(regs,t->month);
76 MSTK_SET_REG_YEAR(regs,t->year - MSTK_YEAR_ZERO);
77
78 tmp = mostek_read(regs + MOSTEK_CREG);
79 tmp &= ~MSTK_CREG_WRITE;
80 mostek_write(regs + MOSTEK_CREG, tmp);
81
82 spin_unlock_irq(&mostek_lock);
83}
84
85static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
86 unsigned long arg)
87{
88 struct rtc_time rtc_tm;
89 void __user *argp = (void __user *)arg;
90
91 switch (cmd)
92 {
93 case RTCGET:
94 memset(&rtc_tm, 0, sizeof(struct rtc_time));
95 get_rtc_time(&rtc_tm);
96
97 if (copy_to_user(argp, &rtc_tm, sizeof(struct rtc_time)))
98 return -EFAULT;
99
100 return 0;
101
102
103 case RTCSET:
104 if (!capable(CAP_SYS_TIME))
105 return -EPERM;
106
107 if (copy_from_user(&rtc_tm, argp, sizeof(struct rtc_time)))
108 return -EFAULT;
109
110 set_rtc_time(&rtc_tm);
111
112 return 0;
113
114 default:
115 return -EINVAL;
116 }
117}
118
119static int rtc_open(struct inode *inode, struct file *file)
120{
121 int ret;
122
123 spin_lock_irq(&mostek_lock);
124 if (rtc_busy) {
125 ret = -EBUSY;
126 } else {
127 rtc_busy = 1;
128 ret = 0;
129 }
130 spin_unlock_irq(&mostek_lock);
131
132 return ret;
133}
134
135static int rtc_release(struct inode *inode, struct file *file)
136{
137 rtc_busy = 0;
138
139 return 0;
140}
141
142static struct file_operations rtc_fops = {
143 .owner = THIS_MODULE,
144 .llseek = no_llseek,
145 .ioctl = rtc_ioctl,
146 .open = rtc_open,
147 .release = rtc_release,
148};
149
150static struct miscdevice rtc_dev = { RTC_MINOR, "rtc", &rtc_fops };
151
152static int __init rtc_sun_init(void)
153{
154 int error;
155
156 /* It is possible we are being driven by some other RTC chip
157 * and thus another RTC driver is handling things.
158 */
159 if (mstk48t02_regs == 0)
160 return -ENODEV;
161
162 error = misc_register(&rtc_dev);
163 if (error) {
164 printk(KERN_ERR "rtc: unable to get misc minor for Mostek\n");
165 return error;
166 }
167
168 return 0;
169}
170
171static void __exit rtc_sun_cleanup(void)
172{
173 misc_deregister(&rtc_dev);
174}
175
176module_init(rtc_sun_init);
177module_exit(rtc_sun_cleanup);
178MODULE_LICENSE("GPL");