Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
f30c2269 | 2 | * include/asm-generic/rtc.h |
1da177e4 LT |
3 | * |
4 | * Author: Tom Rini <trini@mvista.com> | |
5 | * | |
6 | * Based on: | |
7 | * drivers/char/rtc.c | |
8 | * | |
9 | * Please read the COPYING file for all license details. | |
10 | */ | |
11 | ||
12 | #ifndef __ASM_RTC_H__ | |
13 | #define __ASM_RTC_H__ | |
14 | ||
15 | #ifdef __KERNEL__ | |
16 | ||
17 | #include <linux/mc146818rtc.h> | |
18 | #include <linux/rtc.h> | |
19 | #include <linux/bcd.h> | |
20 | ||
21 | #define RTC_PIE 0x40 /* periodic interrupt enable */ | |
22 | #define RTC_AIE 0x20 /* alarm interrupt enable */ | |
23 | #define RTC_UIE 0x10 /* update-finished interrupt enable */ | |
24 | ||
25 | /* some dummy definitions */ | |
26 | #define RTC_BATT_BAD 0x100 /* battery bad */ | |
27 | #define RTC_SQWE 0x08 /* enable square-wave output */ | |
28 | #define RTC_DM_BINARY 0x04 /* all time/date values are BCD if clear */ | |
29 | #define RTC_24H 0x02 /* 24 hour mode - else hours bit 7 means pm */ | |
30 | #define RTC_DST_EN 0x01 /* auto switch DST - works f. USA only */ | |
31 | ||
32 | /* | |
33 | * Returns true if a clock update is in progress | |
34 | */ | |
35 | static inline unsigned char rtc_is_updating(void) | |
36 | { | |
37 | unsigned char uip; | |
38 | ||
39 | spin_lock_irq(&rtc_lock); | |
40 | uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP); | |
41 | spin_unlock_irq(&rtc_lock); | |
42 | return uip; | |
43 | } | |
44 | ||
45 | static inline unsigned int get_rtc_time(struct rtc_time *time) | |
46 | { | |
47 | unsigned long uip_watchdog = jiffies; | |
48 | unsigned char ctrl; | |
49 | #ifdef CONFIG_MACH_DECSTATION | |
50 | unsigned int real_year; | |
51 | #endif | |
52 | ||
53 | /* | |
54 | * read RTC once any update in progress is done. The update | |
55 | * can take just over 2ms. We wait 10 to 20ms. There is no need to | |
56 | * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP. | |
57 | * If you need to know *exactly* when a second has started, enable | |
58 | * periodic update complete interrupts, (via ioctl) and then | |
59 | * immediately read /dev/rtc which will block until you get the IRQ. | |
60 | * Once the read clears, read the RTC time (again via ioctl). Easy. | |
61 | */ | |
62 | ||
63 | if (rtc_is_updating() != 0) | |
64 | while (jiffies - uip_watchdog < 2*HZ/100) { | |
65 | barrier(); | |
66 | cpu_relax(); | |
67 | } | |
68 | ||
69 | /* | |
70 | * Only the values that we read from the RTC are set. We leave | |
71 | * tm_wday, tm_yday and tm_isdst untouched. Even though the | |
72 | * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated | |
73 | * by the RTC when initially set to a non-zero value. | |
74 | */ | |
75 | spin_lock_irq(&rtc_lock); | |
76 | time->tm_sec = CMOS_READ(RTC_SECONDS); | |
77 | time->tm_min = CMOS_READ(RTC_MINUTES); | |
78 | time->tm_hour = CMOS_READ(RTC_HOURS); | |
79 | time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH); | |
80 | time->tm_mon = CMOS_READ(RTC_MONTH); | |
81 | time->tm_year = CMOS_READ(RTC_YEAR); | |
82 | #ifdef CONFIG_MACH_DECSTATION | |
83 | real_year = CMOS_READ(RTC_DEC_YEAR); | |
84 | #endif | |
85 | ctrl = CMOS_READ(RTC_CONTROL); | |
86 | spin_unlock_irq(&rtc_lock); | |
87 | ||
88 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) | |
89 | { | |
90 | BCD_TO_BIN(time->tm_sec); | |
91 | BCD_TO_BIN(time->tm_min); | |
92 | BCD_TO_BIN(time->tm_hour); | |
93 | BCD_TO_BIN(time->tm_mday); | |
94 | BCD_TO_BIN(time->tm_mon); | |
95 | BCD_TO_BIN(time->tm_year); | |
96 | } | |
97 | ||
98 | #ifdef CONFIG_MACH_DECSTATION | |
99 | time->tm_year += real_year - 72; | |
100 | #endif | |
101 | ||
102 | /* | |
103 | * Account for differences between how the RTC uses the values | |
104 | * and how they are defined in a struct rtc_time; | |
105 | */ | |
106 | if (time->tm_year <= 69) | |
107 | time->tm_year += 100; | |
108 | ||
109 | time->tm_mon--; | |
110 | ||
111 | return RTC_24H; | |
112 | } | |
113 | ||
114 | /* Set the current date and time in the real time clock. */ | |
115 | static inline int set_rtc_time(struct rtc_time *time) | |
116 | { | |
eb71c87a | 117 | unsigned long flags; |
1da177e4 LT |
118 | unsigned char mon, day, hrs, min, sec; |
119 | unsigned char save_control, save_freq_select; | |
120 | unsigned int yrs; | |
121 | #ifdef CONFIG_MACH_DECSTATION | |
122 | unsigned int real_yrs, leap_yr; | |
123 | #endif | |
124 | ||
125 | yrs = time->tm_year; | |
126 | mon = time->tm_mon + 1; /* tm_mon starts at zero */ | |
127 | day = time->tm_mday; | |
128 | hrs = time->tm_hour; | |
129 | min = time->tm_min; | |
130 | sec = time->tm_sec; | |
131 | ||
132 | if (yrs > 255) /* They are unsigned */ | |
133 | return -EINVAL; | |
134 | ||
eb71c87a | 135 | spin_lock_irqsave(&rtc_lock, flags); |
1da177e4 LT |
136 | #ifdef CONFIG_MACH_DECSTATION |
137 | real_yrs = yrs; | |
138 | leap_yr = ((!((yrs + 1900) % 4) && ((yrs + 1900) % 100)) || | |
139 | !((yrs + 1900) % 400)); | |
140 | yrs = 72; | |
141 | ||
142 | /* | |
143 | * We want to keep the year set to 73 until March | |
144 | * for non-leap years, so that Feb, 29th is handled | |
145 | * correctly. | |
146 | */ | |
147 | if (!leap_yr && mon < 3) { | |
148 | real_yrs--; | |
149 | yrs = 73; | |
150 | } | |
151 | #endif | |
152 | /* These limits and adjustments are independent of | |
153 | * whether the chip is in binary mode or not. | |
154 | */ | |
155 | if (yrs > 169) { | |
eb71c87a | 156 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 LT |
157 | return -EINVAL; |
158 | } | |
159 | ||
160 | if (yrs >= 100) | |
161 | yrs -= 100; | |
162 | ||
163 | if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) | |
164 | || RTC_ALWAYS_BCD) { | |
165 | BIN_TO_BCD(sec); | |
166 | BIN_TO_BCD(min); | |
167 | BIN_TO_BCD(hrs); | |
168 | BIN_TO_BCD(day); | |
169 | BIN_TO_BCD(mon); | |
170 | BIN_TO_BCD(yrs); | |
171 | } | |
172 | ||
173 | save_control = CMOS_READ(RTC_CONTROL); | |
174 | CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL); | |
175 | save_freq_select = CMOS_READ(RTC_FREQ_SELECT); | |
176 | CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT); | |
177 | ||
178 | #ifdef CONFIG_MACH_DECSTATION | |
179 | CMOS_WRITE(real_yrs, RTC_DEC_YEAR); | |
180 | #endif | |
181 | CMOS_WRITE(yrs, RTC_YEAR); | |
182 | CMOS_WRITE(mon, RTC_MONTH); | |
183 | CMOS_WRITE(day, RTC_DAY_OF_MONTH); | |
184 | CMOS_WRITE(hrs, RTC_HOURS); | |
185 | CMOS_WRITE(min, RTC_MINUTES); | |
186 | CMOS_WRITE(sec, RTC_SECONDS); | |
187 | ||
188 | CMOS_WRITE(save_control, RTC_CONTROL); | |
189 | CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT); | |
190 | ||
eb71c87a | 191 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 LT |
192 | |
193 | return 0; | |
194 | } | |
195 | ||
196 | static inline unsigned int get_rtc_ss(void) | |
197 | { | |
198 | struct rtc_time h; | |
199 | ||
200 | get_rtc_time(&h); | |
201 | return h.tm_sec; | |
202 | } | |
203 | ||
204 | static inline int get_rtc_pll(struct rtc_pll_info *pll) | |
205 | { | |
206 | return -EINVAL; | |
207 | } | |
208 | static inline int set_rtc_pll(struct rtc_pll_info *pll) | |
209 | { | |
210 | return -EINVAL; | |
211 | } | |
212 | ||
213 | #endif /* __KERNEL__ */ | |
214 | #endif /* __ASM_RTC_H__ */ |