Thomas Gleixner | 2874c5f | 2019-05-27 08:55:01 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | /* |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 3 | * Real Time Clock interface for Linux |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * |
| 5 | * Copyright (C) 1996 Paul Gortmaker |
| 6 | * |
| 7 | * This driver allows use of the real time clock (built into |
| 8 | * nearly all computers) from user space. It exports the /dev/rtc |
| 9 | * interface supporting various ioctl() and also the |
| 10 | * /proc/driver/rtc pseudo-file for status information. |
| 11 | * |
| 12 | * The ioctls can be used to set the interrupt behaviour and |
| 13 | * generation rate from the RTC via IRQ 8. Then the /dev/rtc |
| 14 | * interface can be used to make use of these timer interrupts, |
| 15 | * be they interval or alarm based. |
| 16 | * |
| 17 | * The /dev/rtc interface will block on reads until an interrupt |
| 18 | * has been received. If a RTC interrupt has already happened, |
| 19 | * it will output an unsigned long and then block. The output value |
| 20 | * contains the interrupt status in the low byte and the number of |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 21 | * interrupts since the last read in the remaining high bytes. The |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | * /dev/rtc interface can also be used with the select(2) call. |
| 23 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | * Based on other minimal char device drivers, like Alan's |
| 25 | * watchdog, Ted's random, etc. etc. |
| 26 | * |
| 27 | * 1.07 Paul Gortmaker. |
| 28 | * 1.08 Miquel van Smoorenburg: disallow certain things on the |
| 29 | * DEC Alpha as the CMOS clock is also used for other things. |
| 30 | * 1.09 Nikita Schmidt: epoch support and some Alpha cleanup. |
| 31 | * 1.09a Pete Zaitcev: Sun SPARC |
| 32 | * 1.09b Jeff Garzik: Modularize, init cleanup |
| 33 | * 1.09c Jeff Garzik: SMP cleanup |
Ralf Baechle | 12a0a70 | 2006-10-09 23:20:47 +0100 | [diff] [blame] | 34 | * 1.10 Paul Barton-Davis: add support for async I/O |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | * 1.10a Andrea Arcangeli: Alpha updates |
| 36 | * 1.10b Andrew Morton: SMP lock fix |
| 37 | * 1.10c Cesar Barros: SMP locking fixes and cleanup |
| 38 | * 1.10d Paul Gortmaker: delete paranoia check in rtc_exit |
| 39 | * 1.10e Maciej W. Rozycki: Handle DECstation's year weirdness. |
Ralf Baechle | 12a0a70 | 2006-10-09 23:20:47 +0100 | [diff] [blame] | 40 | * 1.11 Takashi Iwai: Kernel access functions |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | * rtc_register/rtc_unregister/rtc_control |
| 42 | * 1.11a Daniele Bellucci: Audit create_proc_read_entry in rtc_init |
| 43 | * 1.12 Venkatesh Pallipadi: Hooks for emulating rtc on HPET base-timer |
| 44 | * CONFIG_HPET_EMULATE_RTC |
Maciej W. Rozycki | 38e0e8c | 2006-07-10 04:45:30 -0700 | [diff] [blame] | 45 | * 1.12a Maciej W. Rozycki: Handle memory-mapped chips properly. |
Alan Cox | b759958 | 2006-01-11 12:17:32 -0800 | [diff] [blame] | 46 | * 1.12ac Alan Cox: Allow read access to the day of week register |
David John | 048cd58 | 2008-10-23 13:55:56 +0530 | [diff] [blame] | 47 | * 1.12b David John: Remove calls to the BKL. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | */ |
| 49 | |
David John | 048cd58 | 2008-10-23 13:55:56 +0530 | [diff] [blame] | 50 | #define RTC_VERSION "1.12b" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | /* |
| 53 | * Note that *all* calls to CMOS_READ and CMOS_WRITE are done with |
| 54 | * interrupts disabled. Due to the index-port/data-port (0x70/0x71) |
| 55 | * design of the RTC, we don't want two different things trying to |
Michael Witten | 5196d20 | 2012-01-24 22:48:04 +0000 | [diff] [blame] | 56 | * get to it at once. (e.g. the periodic 11 min sync from |
| 57 | * kernel/time/ntp.c vs. this driver.) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | */ |
| 59 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | #include <linux/interrupt.h> |
| 61 | #include <linux/module.h> |
| 62 | #include <linux/kernel.h> |
| 63 | #include <linux/types.h> |
| 64 | #include <linux/miscdevice.h> |
| 65 | #include <linux/ioport.h> |
| 66 | #include <linux/fcntl.h> |
| 67 | #include <linux/mc146818rtc.h> |
| 68 | #include <linux/init.h> |
| 69 | #include <linux/poll.h> |
| 70 | #include <linux/proc_fs.h> |
| 71 | #include <linux/seq_file.h> |
| 72 | #include <linux/spinlock.h> |
Ingo Molnar | 174cd4b | 2017-02-02 19:15:33 +0100 | [diff] [blame] | 73 | #include <linux/sched/signal.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | #include <linux/sysctl.h> |
| 75 | #include <linux/wait.h> |
| 76 | #include <linux/bcd.h> |
Luca Falavigna | 47f176f | 2005-06-28 20:44:42 -0700 | [diff] [blame] | 77 | #include <linux/delay.h> |
Alan Cox | 53f1b14 | 2008-07-23 21:30:32 -0700 | [diff] [blame] | 78 | #include <linux/uaccess.h> |
Christian Dietrich | a28ee47 | 2011-06-04 17:36:33 +0200 | [diff] [blame] | 79 | #include <linux/ratelimit.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | |
| 81 | #include <asm/current.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | |
Chris Wright | 55f93af | 2007-07-21 17:10:09 +0200 | [diff] [blame] | 83 | #ifdef CONFIG_X86 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | #include <asm/hpet.h> |
| 85 | #endif |
| 86 | |
David S. Miller | cdee99d | 2007-07-19 13:59:58 -0700 | [diff] [blame] | 87 | #ifdef CONFIG_SPARC32 |
David S. Miller | 7508132 | 2008-08-30 00:23:51 -0700 | [diff] [blame] | 88 | #include <linux/of.h> |
| 89 | #include <linux/of_device.h> |
| 90 | #include <asm/io.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | |
| 92 | static unsigned long rtc_port; |
David S. Miller | 7508132 | 2008-08-30 00:23:51 -0700 | [diff] [blame] | 93 | static int rtc_irq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | #endif |
| 95 | |
David Brownell | 0f4d3fd | 2008-10-15 22:03:00 -0700 | [diff] [blame] | 96 | #ifdef CONFIG_HPET_EMULATE_RTC |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | #undef RTC_IRQ |
| 98 | #endif |
| 99 | |
| 100 | #ifdef RTC_IRQ |
| 101 | static int rtc_has_irq = 1; |
| 102 | #endif |
| 103 | |
| 104 | #ifndef CONFIG_HPET_EMULATE_RTC |
| 105 | #define is_hpet_enabled() 0 |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 106 | #define hpet_set_alarm_time(hrs, min, sec) 0 |
| 107 | #define hpet_set_periodic_freq(arg) 0 |
| 108 | #define hpet_mask_rtc_irq_bit(arg) 0 |
| 109 | #define hpet_set_rtc_irq_bit(arg) 0 |
| 110 | #define hpet_rtc_timer_init() do { } while (0) |
| 111 | #define hpet_rtc_dropped_irq() 0 |
David Howells | 32fa458 | 2008-02-28 13:29:43 +0000 | [diff] [blame] | 112 | #define hpet_register_irq_handler(h) ({ 0; }) |
| 113 | #define hpet_unregister_irq_handler(h) ({ 0; }) |
Andrew Morton | 533ffc2 | 2006-12-22 01:06:36 -0800 | [diff] [blame] | 114 | #ifdef RTC_IRQ |
| 115 | static irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) |
| 116 | { |
| 117 | return 0; |
| 118 | } |
| 119 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | #endif |
| 121 | |
| 122 | /* |
| 123 | * We sponge a minor off of the misc major. No need slurping |
| 124 | * up another valuable major dev number for this. If you add |
| 125 | * an ioctl, make sure you don't conflict with SPARC's RTC |
| 126 | * ioctls. |
| 127 | */ |
| 128 | |
| 129 | static struct fasync_struct *rtc_async_queue; |
| 130 | |
| 131 | static DECLARE_WAIT_QUEUE_HEAD(rtc_wait); |
| 132 | |
| 133 | #ifdef RTC_IRQ |
Kees Cook | 24ed960 | 2017-08-28 11:28:21 -0700 | [diff] [blame] | 134 | static void rtc_dropped_irq(struct timer_list *unused); |
Jiri Slaby | 40565f1 | 2007-02-12 00:52:31 -0800 | [diff] [blame] | 135 | |
Kees Cook | 1d27e3e | 2017-10-04 16:27:04 -0700 | [diff] [blame] | 136 | static DEFINE_TIMER(rtc_irq_timer, rtc_dropped_irq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | #endif |
| 138 | |
| 139 | static ssize_t rtc_read(struct file *file, char __user *buf, |
| 140 | size_t count, loff_t *ppos); |
| 141 | |
Alan Cox | 53f1b14 | 2008-07-23 21:30:32 -0700 | [diff] [blame] | 142 | static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg); |
Adrian Bunk | 9580d85 | 2008-07-25 19:46:25 -0700 | [diff] [blame] | 143 | static void rtc_get_rtc_time(struct rtc_time *rtc_tm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | |
| 145 | #ifdef RTC_IRQ |
Al Viro | afc9a42 | 2017-07-03 06:39:46 -0400 | [diff] [blame] | 146 | static __poll_t rtc_poll(struct file *file, poll_table *wait); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 147 | #endif |
| 148 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 149 | static void get_rtc_alm_time(struct rtc_time *alm_tm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | #ifdef RTC_IRQ |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 151 | static void set_rtc_irq_bit_locked(unsigned char bit); |
| 152 | static void mask_rtc_irq_bit_locked(unsigned char bit); |
| 153 | |
| 154 | static inline void set_rtc_irq_bit(unsigned char bit) |
| 155 | { |
| 156 | spin_lock_irq(&rtc_lock); |
| 157 | set_rtc_irq_bit_locked(bit); |
| 158 | spin_unlock_irq(&rtc_lock); |
| 159 | } |
| 160 | |
| 161 | static void mask_rtc_irq_bit(unsigned char bit) |
| 162 | { |
| 163 | spin_lock_irq(&rtc_lock); |
| 164 | mask_rtc_irq_bit_locked(bit); |
| 165 | spin_unlock_irq(&rtc_lock); |
| 166 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | #endif |
| 168 | |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 169 | #ifdef CONFIG_PROC_FS |
Christoph Hellwig | 3f3942a | 2018-05-15 15:57:23 +0200 | [diff] [blame] | 170 | static int rtc_proc_show(struct seq_file *seq, void *v); |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 171 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | |
| 173 | /* |
| 174 | * Bits in rtc_status. (6 bits of room for future expansion) |
| 175 | */ |
| 176 | |
| 177 | #define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */ |
| 178 | #define RTC_TIMER_ON 0x02 /* missed irq timer active */ |
| 179 | |
| 180 | /* |
| 181 | * rtc_status is never changed by rtc_interrupt, and ioctl/open/close is |
David John | 048cd58 | 2008-10-23 13:55:56 +0530 | [diff] [blame] | 182 | * protected by the spin lock rtc_lock. However, ioctl can still disable the |
| 183 | * timer in rtc_status and then with del_timer after the interrupt has read |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | * rtc_status but before mod_timer is called, which would then reenable the |
| 185 | * timer (but you would need to have an awful timing before you'd trip on it) |
| 186 | */ |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 187 | static unsigned long rtc_status; /* bitmapped status byte. */ |
| 188 | static unsigned long rtc_freq; /* Current periodic IRQ rate */ |
| 189 | static unsigned long rtc_irq_data; /* our output to the world */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 190 | static unsigned long rtc_max_user_freq = 64; /* > this, need CAP_SYS_RESOURCE */ |
| 191 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | /* |
| 193 | * If this driver ever becomes modularised, it will be really nice |
| 194 | * to make the epoch retain its value across module reload... |
| 195 | */ |
| 196 | |
| 197 | static unsigned long epoch = 1900; /* year corresponding to 0x00 */ |
| 198 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 199 | static const unsigned char days_in_mo[] = |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; |
| 201 | |
| 202 | /* |
| 203 | * Returns true if a clock update is in progress |
| 204 | */ |
| 205 | static inline unsigned char rtc_is_updating(void) |
| 206 | { |
Peter Zijlstra | 0b16f21 | 2006-09-25 16:24:23 -0700 | [diff] [blame] | 207 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | unsigned char uip; |
| 209 | |
Peter Zijlstra | 0b16f21 | 2006-09-25 16:24:23 -0700 | [diff] [blame] | 210 | spin_lock_irqsave(&rtc_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP); |
Peter Zijlstra | 0b16f21 | 2006-09-25 16:24:23 -0700 | [diff] [blame] | 212 | spin_unlock_irqrestore(&rtc_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | return uip; |
| 214 | } |
| 215 | |
| 216 | #ifdef RTC_IRQ |
| 217 | /* |
Michael Opdenacker | d88ed62 | 2013-10-13 06:14:42 +0200 | [diff] [blame] | 218 | * A very tiny interrupt handler. It runs with interrupts disabled, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | * but there is possibility of conflicting with the set_rtc_mmss() |
| 220 | * call (the rtc irq and the timer irq can easily run at the same |
| 221 | * time in two different CPUs). So we need to serialize |
| 222 | * accesses to the chip with the rtc_lock spinlock that each |
| 223 | * architecture should implement in the timer code. |
| 224 | * (See ./arch/XXXX/kernel/time.c for the set_rtc_mmss() function.) |
| 225 | */ |
| 226 | |
Adrian Bunk | 9580d85 | 2008-07-25 19:46:25 -0700 | [diff] [blame] | 227 | static irqreturn_t rtc_interrupt(int irq, void *dev_id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | { |
| 229 | /* |
| 230 | * Can be an alarm interrupt, update complete interrupt, |
| 231 | * or a periodic interrupt. We store the status in the |
| 232 | * low byte and the number of interrupts received since |
| 233 | * the last read in the remainder of rtc_irq_data. |
| 234 | */ |
| 235 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 236 | spin_lock(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | rtc_irq_data += 0x100; |
| 238 | rtc_irq_data &= ~0xff; |
| 239 | if (is_hpet_enabled()) { |
| 240 | /* |
| 241 | * In this case it is HPET RTC interrupt handler |
| 242 | * calling us, with the interrupt information |
| 243 | * passed as arg1, instead of irq. |
| 244 | */ |
| 245 | rtc_irq_data |= (unsigned long)irq & 0xF0; |
| 246 | } else { |
| 247 | rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0); |
| 248 | } |
| 249 | |
| 250 | if (rtc_status & RTC_TIMER_ON) |
| 251 | mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100); |
| 252 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 253 | spin_unlock(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 255 | wake_up_interruptible(&rtc_wait); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 256 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 257 | kill_fasync(&rtc_async_queue, SIGIO, POLL_IN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | |
| 259 | return IRQ_HANDLED; |
| 260 | } |
| 261 | #endif |
| 262 | |
| 263 | /* |
| 264 | * sysctl-tuning infrastructure. |
| 265 | */ |
Joe Perches | a151427 | 2013-06-13 19:37:35 -0700 | [diff] [blame] | 266 | static struct ctl_table rtc_table[] = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | .procname = "max-user-freq", |
| 269 | .data = &rtc_max_user_freq, |
| 270 | .maxlen = sizeof(int), |
| 271 | .mode = 0644, |
Eric W. Biederman | 6d45611 | 2009-11-16 03:11:48 -0800 | [diff] [blame] | 272 | .proc_handler = proc_dointvec, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | }, |
Eric W. Biederman | 894d249 | 2009-11-05 14:34:02 -0800 | [diff] [blame] | 274 | { } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | }; |
| 276 | |
Joe Perches | a151427 | 2013-06-13 19:37:35 -0700 | [diff] [blame] | 277 | static struct ctl_table rtc_root[] = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | .procname = "rtc", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 280 | .mode = 0555, |
| 281 | .child = rtc_table, |
| 282 | }, |
Eric W. Biederman | 894d249 | 2009-11-05 14:34:02 -0800 | [diff] [blame] | 283 | { } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | }; |
| 285 | |
Joe Perches | a151427 | 2013-06-13 19:37:35 -0700 | [diff] [blame] | 286 | static struct ctl_table dev_root[] = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 287 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | .procname = "dev", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | .mode = 0555, |
| 290 | .child = rtc_root, |
| 291 | }, |
Eric W. Biederman | 894d249 | 2009-11-05 14:34:02 -0800 | [diff] [blame] | 292 | { } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 293 | }; |
| 294 | |
| 295 | static struct ctl_table_header *sysctl_header; |
| 296 | |
| 297 | static int __init init_sysctl(void) |
| 298 | { |
Eric W. Biederman | 0b4d414 | 2007-02-14 00:34:09 -0800 | [diff] [blame] | 299 | sysctl_header = register_sysctl_table(dev_root); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | return 0; |
| 301 | } |
| 302 | |
| 303 | static void __exit cleanup_sysctl(void) |
| 304 | { |
| 305 | unregister_sysctl_table(sysctl_header); |
| 306 | } |
| 307 | |
| 308 | /* |
| 309 | * Now all the various file operations that we export. |
| 310 | */ |
| 311 | |
| 312 | static ssize_t rtc_read(struct file *file, char __user *buf, |
| 313 | size_t count, loff_t *ppos) |
| 314 | { |
| 315 | #ifndef RTC_IRQ |
| 316 | return -EIO; |
| 317 | #else |
| 318 | DECLARE_WAITQUEUE(wait, current); |
| 319 | unsigned long data; |
| 320 | ssize_t retval; |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 321 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | if (rtc_has_irq == 0) |
| 323 | return -EIO; |
| 324 | |
Maciej W. Rozycki | 38e0e8c | 2006-07-10 04:45:30 -0700 | [diff] [blame] | 325 | /* |
| 326 | * Historically this function used to assume that sizeof(unsigned long) |
| 327 | * is the same in userspace and kernelspace. This lead to problems |
| 328 | * for configurations with multiple ABIs such a the MIPS o32 and 64 |
| 329 | * ABIs supported on the same kernel. So now we support read of both |
| 330 | * 4 and 8 bytes and assume that's the sizeof(unsigned long) in the |
| 331 | * userspace ABI. |
| 332 | */ |
| 333 | if (count != sizeof(unsigned int) && count != sizeof(unsigned long)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 334 | return -EINVAL; |
| 335 | |
| 336 | add_wait_queue(&rtc_wait, &wait); |
| 337 | |
| 338 | do { |
| 339 | /* First make it right. Then make it fast. Putting this whole |
| 340 | * block within the parentheses of a while would be too |
| 341 | * confusing. And no, xchg() is not the answer. */ |
| 342 | |
| 343 | __set_current_state(TASK_INTERRUPTIBLE); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 344 | |
| 345 | spin_lock_irq(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | data = rtc_irq_data; |
| 347 | rtc_irq_data = 0; |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 348 | spin_unlock_irq(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 349 | |
| 350 | if (data != 0) |
| 351 | break; |
| 352 | |
| 353 | if (file->f_flags & O_NONBLOCK) { |
| 354 | retval = -EAGAIN; |
| 355 | goto out; |
| 356 | } |
| 357 | if (signal_pending(current)) { |
| 358 | retval = -ERESTARTSYS; |
| 359 | goto out; |
| 360 | } |
| 361 | schedule(); |
| 362 | } while (1); |
| 363 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 364 | if (count == sizeof(unsigned int)) { |
| 365 | retval = put_user(data, |
| 366 | (unsigned int __user *)buf) ?: sizeof(int); |
| 367 | } else { |
| 368 | retval = put_user(data, |
| 369 | (unsigned long __user *)buf) ?: sizeof(long); |
| 370 | } |
Maciej W. Rozycki | 38e0e8c | 2006-07-10 04:45:30 -0700 | [diff] [blame] | 371 | if (!retval) |
| 372 | retval = count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 373 | out: |
Milind Arun Choudhary | cc0a8fb | 2007-05-08 00:30:52 -0700 | [diff] [blame] | 374 | __set_current_state(TASK_RUNNING); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | remove_wait_queue(&rtc_wait, &wait); |
| 376 | |
| 377 | return retval; |
| 378 | #endif |
| 379 | } |
| 380 | |
| 381 | static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel) |
| 382 | { |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 383 | struct rtc_time wtime; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 384 | |
| 385 | #ifdef RTC_IRQ |
| 386 | if (rtc_has_irq == 0) { |
| 387 | switch (cmd) { |
| 388 | case RTC_AIE_OFF: |
| 389 | case RTC_AIE_ON: |
| 390 | case RTC_PIE_OFF: |
| 391 | case RTC_PIE_ON: |
| 392 | case RTC_UIE_OFF: |
| 393 | case RTC_UIE_ON: |
| 394 | case RTC_IRQP_READ: |
| 395 | case RTC_IRQP_SET: |
| 396 | return -EINVAL; |
Peter Senna Tschudin | f8885c2 | 2012-09-12 19:03:18 +0200 | [diff] [blame] | 397 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 398 | } |
| 399 | #endif |
| 400 | |
| 401 | switch (cmd) { |
| 402 | #ifdef RTC_IRQ |
| 403 | case RTC_AIE_OFF: /* Mask alarm int. enab. bit */ |
| 404 | { |
| 405 | mask_rtc_irq_bit(RTC_AIE); |
| 406 | return 0; |
| 407 | } |
| 408 | case RTC_AIE_ON: /* Allow alarm interrupts. */ |
| 409 | { |
| 410 | set_rtc_irq_bit(RTC_AIE); |
| 411 | return 0; |
| 412 | } |
| 413 | case RTC_PIE_OFF: /* Mask periodic int. enab. bit */ |
| 414 | { |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 415 | /* can be called from isr via rtc_control() */ |
| 416 | unsigned long flags; |
| 417 | |
| 418 | spin_lock_irqsave(&rtc_lock, flags); |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 419 | mask_rtc_irq_bit_locked(RTC_PIE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 420 | if (rtc_status & RTC_TIMER_ON) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | rtc_status &= ~RTC_TIMER_ON; |
| 422 | del_timer(&rtc_irq_timer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | } |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 424 | spin_unlock_irqrestore(&rtc_lock, flags); |
| 425 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 426 | return 0; |
| 427 | } |
| 428 | case RTC_PIE_ON: /* Allow periodic ints */ |
| 429 | { |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 430 | /* can be called from isr via rtc_control() */ |
| 431 | unsigned long flags; |
| 432 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | /* |
| 434 | * We don't really want Joe User enabling more |
| 435 | * than 64Hz of interrupts on a multi-user machine. |
| 436 | */ |
| 437 | if (!kernel && (rtc_freq > rtc_max_user_freq) && |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 438 | (!capable(CAP_SYS_RESOURCE))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | return -EACCES; |
| 440 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 441 | spin_lock_irqsave(&rtc_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 442 | if (!(rtc_status & RTC_TIMER_ON)) { |
Jiri Slaby | 40565f1 | 2007-02-12 00:52:31 -0800 | [diff] [blame] | 443 | mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + |
| 444 | 2*HZ/100); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 445 | rtc_status |= RTC_TIMER_ON; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 446 | } |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 447 | set_rtc_irq_bit_locked(RTC_PIE); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 448 | spin_unlock_irqrestore(&rtc_lock, flags); |
| 449 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 450 | return 0; |
| 451 | } |
| 452 | case RTC_UIE_OFF: /* Mask ints from RTC updates. */ |
| 453 | { |
| 454 | mask_rtc_irq_bit(RTC_UIE); |
| 455 | return 0; |
| 456 | } |
| 457 | case RTC_UIE_ON: /* Allow ints for RTC updates. */ |
| 458 | { |
| 459 | set_rtc_irq_bit(RTC_UIE); |
| 460 | return 0; |
| 461 | } |
| 462 | #endif |
| 463 | case RTC_ALM_READ: /* Read the present alarm time */ |
| 464 | { |
| 465 | /* |
| 466 | * This returns a struct rtc_time. Reading >= 0xc0 |
| 467 | * means "don't care" or "match all". Only the tm_hour, |
| 468 | * tm_min, and tm_sec values are filled in. |
| 469 | */ |
| 470 | memset(&wtime, 0, sizeof(struct rtc_time)); |
| 471 | get_rtc_alm_time(&wtime); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 472 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | } |
| 474 | case RTC_ALM_SET: /* Store a time into the alarm */ |
| 475 | { |
| 476 | /* |
| 477 | * This expects a struct rtc_time. Writing 0xff means |
| 478 | * "don't care" or "match all". Only the tm_hour, |
| 479 | * tm_min and tm_sec are used. |
| 480 | */ |
| 481 | unsigned char hrs, min, sec; |
| 482 | struct rtc_time alm_tm; |
| 483 | |
| 484 | if (copy_from_user(&alm_tm, (struct rtc_time __user *)arg, |
| 485 | sizeof(struct rtc_time))) |
| 486 | return -EFAULT; |
| 487 | |
| 488 | hrs = alm_tm.tm_hour; |
| 489 | min = alm_tm.tm_min; |
| 490 | sec = alm_tm.tm_sec; |
| 491 | |
| 492 | spin_lock_irq(&rtc_lock); |
| 493 | if (hpet_set_alarm_time(hrs, min, sec)) { |
| 494 | /* |
| 495 | * Fallthru and set alarm time in CMOS too, |
| 496 | * so that we will get proper value in RTC_ALM_READ |
| 497 | */ |
| 498 | } |
| 499 | if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) || |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 500 | RTC_ALWAYS_BCD) { |
| 501 | if (sec < 60) |
Adrian Bunk | 357c6e6 | 2008-10-18 20:28:42 -0700 | [diff] [blame] | 502 | sec = bin2bcd(sec); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 503 | else |
| 504 | sec = 0xff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 506 | if (min < 60) |
Adrian Bunk | 357c6e6 | 2008-10-18 20:28:42 -0700 | [diff] [blame] | 507 | min = bin2bcd(min); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 508 | else |
| 509 | min = 0xff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 511 | if (hrs < 24) |
Adrian Bunk | 357c6e6 | 2008-10-18 20:28:42 -0700 | [diff] [blame] | 512 | hrs = bin2bcd(hrs); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 513 | else |
| 514 | hrs = 0xff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | } |
| 516 | CMOS_WRITE(hrs, RTC_HOURS_ALARM); |
| 517 | CMOS_WRITE(min, RTC_MINUTES_ALARM); |
| 518 | CMOS_WRITE(sec, RTC_SECONDS_ALARM); |
| 519 | spin_unlock_irq(&rtc_lock); |
| 520 | |
| 521 | return 0; |
| 522 | } |
| 523 | case RTC_RD_TIME: /* Read the time/date from RTC */ |
| 524 | { |
| 525 | memset(&wtime, 0, sizeof(struct rtc_time)); |
| 526 | rtc_get_rtc_time(&wtime); |
| 527 | break; |
| 528 | } |
| 529 | case RTC_SET_TIME: /* Set the RTC */ |
| 530 | { |
| 531 | struct rtc_time rtc_tm; |
| 532 | unsigned char mon, day, hrs, min, sec, leap_yr; |
| 533 | unsigned char save_control, save_freq_select; |
| 534 | unsigned int yrs; |
| 535 | #ifdef CONFIG_MACH_DECSTATION |
| 536 | unsigned int real_yrs; |
| 537 | #endif |
| 538 | |
| 539 | if (!capable(CAP_SYS_TIME)) |
| 540 | return -EACCES; |
| 541 | |
| 542 | if (copy_from_user(&rtc_tm, (struct rtc_time __user *)arg, |
| 543 | sizeof(struct rtc_time))) |
| 544 | return -EFAULT; |
| 545 | |
| 546 | yrs = rtc_tm.tm_year + 1900; |
| 547 | mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */ |
| 548 | day = rtc_tm.tm_mday; |
| 549 | hrs = rtc_tm.tm_hour; |
| 550 | min = rtc_tm.tm_min; |
| 551 | sec = rtc_tm.tm_sec; |
| 552 | |
| 553 | if (yrs < 1970) |
| 554 | return -EINVAL; |
| 555 | |
| 556 | leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400)); |
| 557 | |
| 558 | if ((mon > 12) || (day == 0)) |
| 559 | return -EINVAL; |
| 560 | |
| 561 | if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr))) |
| 562 | return -EINVAL; |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 563 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 564 | if ((hrs >= 24) || (min >= 60) || (sec >= 60)) |
| 565 | return -EINVAL; |
| 566 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 567 | yrs -= epoch; |
| 568 | if (yrs > 255) /* They are unsigned */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 569 | return -EINVAL; |
| 570 | |
| 571 | spin_lock_irq(&rtc_lock); |
| 572 | #ifdef CONFIG_MACH_DECSTATION |
| 573 | real_yrs = yrs; |
| 574 | yrs = 72; |
| 575 | |
| 576 | /* |
| 577 | * We want to keep the year set to 73 until March |
| 578 | * for non-leap years, so that Feb, 29th is handled |
| 579 | * correctly. |
| 580 | */ |
| 581 | if (!leap_yr && mon < 3) { |
| 582 | real_yrs--; |
| 583 | yrs = 73; |
| 584 | } |
| 585 | #endif |
| 586 | /* These limits and adjustments are independent of |
| 587 | * whether the chip is in binary mode or not. |
| 588 | */ |
| 589 | if (yrs > 169) { |
| 590 | spin_unlock_irq(&rtc_lock); |
| 591 | return -EINVAL; |
| 592 | } |
| 593 | if (yrs >= 100) |
| 594 | yrs -= 100; |
| 595 | |
| 596 | if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) |
| 597 | || RTC_ALWAYS_BCD) { |
Adrian Bunk | 357c6e6 | 2008-10-18 20:28:42 -0700 | [diff] [blame] | 598 | sec = bin2bcd(sec); |
| 599 | min = bin2bcd(min); |
| 600 | hrs = bin2bcd(hrs); |
| 601 | day = bin2bcd(day); |
| 602 | mon = bin2bcd(mon); |
| 603 | yrs = bin2bcd(yrs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 604 | } |
| 605 | |
| 606 | save_control = CMOS_READ(RTC_CONTROL); |
| 607 | CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL); |
| 608 | save_freq_select = CMOS_READ(RTC_FREQ_SELECT); |
| 609 | CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT); |
| 610 | |
| 611 | #ifdef CONFIG_MACH_DECSTATION |
| 612 | CMOS_WRITE(real_yrs, RTC_DEC_YEAR); |
| 613 | #endif |
| 614 | CMOS_WRITE(yrs, RTC_YEAR); |
| 615 | CMOS_WRITE(mon, RTC_MONTH); |
| 616 | CMOS_WRITE(day, RTC_DAY_OF_MONTH); |
| 617 | CMOS_WRITE(hrs, RTC_HOURS); |
| 618 | CMOS_WRITE(min, RTC_MINUTES); |
| 619 | CMOS_WRITE(sec, RTC_SECONDS); |
| 620 | |
| 621 | CMOS_WRITE(save_control, RTC_CONTROL); |
| 622 | CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT); |
| 623 | |
| 624 | spin_unlock_irq(&rtc_lock); |
| 625 | return 0; |
| 626 | } |
| 627 | #ifdef RTC_IRQ |
| 628 | case RTC_IRQP_READ: /* Read the periodic IRQ rate. */ |
| 629 | { |
| 630 | return put_user(rtc_freq, (unsigned long __user *)arg); |
| 631 | } |
| 632 | case RTC_IRQP_SET: /* Set periodic IRQ rate. */ |
| 633 | { |
| 634 | int tmp = 0; |
| 635 | unsigned char val; |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 636 | /* can be called from isr via rtc_control() */ |
| 637 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 639 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 640 | * The max we can do is 8192Hz. |
| 641 | */ |
| 642 | if ((arg < 2) || (arg > 8192)) |
| 643 | return -EINVAL; |
| 644 | /* |
| 645 | * We don't really want Joe User generating more |
| 646 | * than 64Hz of interrupts on a multi-user machine. |
| 647 | */ |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 648 | if (!kernel && (arg > rtc_max_user_freq) && |
| 649 | !capable(CAP_SYS_RESOURCE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 650 | return -EACCES; |
| 651 | |
| 652 | while (arg > (1<<tmp)) |
| 653 | tmp++; |
| 654 | |
| 655 | /* |
| 656 | * Check that the input was really a power of 2. |
| 657 | */ |
| 658 | if (arg != (1<<tmp)) |
| 659 | return -EINVAL; |
| 660 | |
Paul Gortmaker | 61ca9da | 2008-07-10 17:30:48 -0700 | [diff] [blame] | 661 | rtc_freq = arg; |
| 662 | |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 663 | spin_lock_irqsave(&rtc_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | if (hpet_set_periodic_freq(arg)) { |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 665 | spin_unlock_irqrestore(&rtc_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 666 | return 0; |
| 667 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | |
| 669 | val = CMOS_READ(RTC_FREQ_SELECT) & 0xf0; |
| 670 | val |= (16 - tmp); |
| 671 | CMOS_WRITE(val, RTC_FREQ_SELECT); |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 672 | spin_unlock_irqrestore(&rtc_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 673 | return 0; |
| 674 | } |
| 675 | #endif |
| 676 | case RTC_EPOCH_READ: /* Read the epoch. */ |
| 677 | { |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 678 | return put_user(epoch, (unsigned long __user *)arg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 679 | } |
| 680 | case RTC_EPOCH_SET: /* Set the epoch. */ |
| 681 | { |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 682 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | * There were no RTC clocks before 1900. |
| 684 | */ |
| 685 | if (arg < 1900) |
| 686 | return -EINVAL; |
| 687 | |
| 688 | if (!capable(CAP_SYS_TIME)) |
| 689 | return -EACCES; |
| 690 | |
| 691 | epoch = arg; |
| 692 | return 0; |
| 693 | } |
| 694 | default: |
| 695 | return -ENOTTY; |
| 696 | } |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 697 | return copy_to_user((void __user *)arg, |
| 698 | &wtime, sizeof wtime) ? -EFAULT : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | } |
| 700 | |
Alan Cox | 53f1b14 | 2008-07-23 21:30:32 -0700 | [diff] [blame] | 701 | static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | { |
Alan Cox | 53f1b14 | 2008-07-23 21:30:32 -0700 | [diff] [blame] | 703 | long ret; |
Alan Cox | 53f1b14 | 2008-07-23 21:30:32 -0700 | [diff] [blame] | 704 | ret = rtc_do_ioctl(cmd, arg, 0); |
Alan Cox | 53f1b14 | 2008-07-23 21:30:32 -0700 | [diff] [blame] | 705 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | } |
| 707 | |
| 708 | /* |
| 709 | * We enforce only one user at a time here with the open/close. |
| 710 | * Also clear the previous interrupt data on an open, and clean |
| 711 | * up things on a close. |
| 712 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | static int rtc_open(struct inode *inode, struct file *file) |
| 714 | { |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 715 | spin_lock_irq(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 716 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 717 | if (rtc_status & RTC_IS_OPEN) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 718 | goto out_busy; |
| 719 | |
| 720 | rtc_status |= RTC_IS_OPEN; |
| 721 | |
| 722 | rtc_irq_data = 0; |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 723 | spin_unlock_irq(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | return 0; |
| 725 | |
| 726 | out_busy: |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 727 | spin_unlock_irq(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 728 | return -EBUSY; |
| 729 | } |
| 730 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 731 | static int rtc_fasync(int fd, struct file *filp, int on) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | { |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 733 | return fasync_helper(fd, filp, on, &rtc_async_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 734 | } |
| 735 | |
| 736 | static int rtc_release(struct inode *inode, struct file *file) |
| 737 | { |
| 738 | #ifdef RTC_IRQ |
| 739 | unsigned char tmp; |
| 740 | |
| 741 | if (rtc_has_irq == 0) |
| 742 | goto no_irq; |
| 743 | |
| 744 | /* |
| 745 | * Turn off all interrupts once the device is no longer |
| 746 | * in use, and clear the data. |
| 747 | */ |
| 748 | |
| 749 | spin_lock_irq(&rtc_lock); |
| 750 | if (!hpet_mask_rtc_irq_bit(RTC_PIE | RTC_AIE | RTC_UIE)) { |
| 751 | tmp = CMOS_READ(RTC_CONTROL); |
| 752 | tmp &= ~RTC_PIE; |
| 753 | tmp &= ~RTC_AIE; |
| 754 | tmp &= ~RTC_UIE; |
| 755 | CMOS_WRITE(tmp, RTC_CONTROL); |
| 756 | CMOS_READ(RTC_INTR_FLAGS); |
| 757 | } |
| 758 | if (rtc_status & RTC_TIMER_ON) { |
| 759 | rtc_status &= ~RTC_TIMER_ON; |
| 760 | del_timer(&rtc_irq_timer); |
| 761 | } |
| 762 | spin_unlock_irq(&rtc_lock); |
| 763 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 764 | no_irq: |
| 765 | #endif |
| 766 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 767 | spin_lock_irq(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 768 | rtc_irq_data = 0; |
| 769 | rtc_status &= ~RTC_IS_OPEN; |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 770 | spin_unlock_irq(&rtc_lock); |
| 771 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | return 0; |
| 773 | } |
| 774 | |
| 775 | #ifdef RTC_IRQ |
Al Viro | afc9a42 | 2017-07-03 06:39:46 -0400 | [diff] [blame] | 776 | static __poll_t rtc_poll(struct file *file, poll_table *wait) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 777 | { |
| 778 | unsigned long l; |
| 779 | |
| 780 | if (rtc_has_irq == 0) |
| 781 | return 0; |
| 782 | |
| 783 | poll_wait(file, &rtc_wait, wait); |
| 784 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 785 | spin_lock_irq(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 786 | l = rtc_irq_data; |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 787 | spin_unlock_irq(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 788 | |
| 789 | if (l != 0) |
Linus Torvalds | a9a0884 | 2018-02-11 14:34:03 -0800 | [diff] [blame] | 790 | return EPOLLIN | EPOLLRDNORM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 791 | return 0; |
| 792 | } |
| 793 | #endif |
| 794 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 795 | /* |
| 796 | * The various file operations we support. |
| 797 | */ |
| 798 | |
Arjan van de Ven | 62322d2 | 2006-07-03 00:24:21 -0700 | [diff] [blame] | 799 | static const struct file_operations rtc_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 800 | .owner = THIS_MODULE, |
| 801 | .llseek = no_llseek, |
| 802 | .read = rtc_read, |
| 803 | #ifdef RTC_IRQ |
| 804 | .poll = rtc_poll, |
| 805 | #endif |
Alan Cox | 53f1b14 | 2008-07-23 21:30:32 -0700 | [diff] [blame] | 806 | .unlocked_ioctl = rtc_ioctl, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 807 | .open = rtc_open, |
| 808 | .release = rtc_release, |
| 809 | .fasync = rtc_fasync, |
| 810 | }; |
| 811 | |
| 812 | static struct miscdevice rtc_dev = { |
| 813 | .minor = RTC_MINOR, |
| 814 | .name = "rtc", |
| 815 | .fops = &rtc_fops, |
| 816 | }; |
| 817 | |
Bjorn Helgaas | 9626f1f1 | 2007-11-14 16:59:57 -0800 | [diff] [blame] | 818 | static resource_size_t rtc_size; |
| 819 | |
| 820 | static struct resource * __init rtc_request_region(resource_size_t size) |
| 821 | { |
| 822 | struct resource *r; |
| 823 | |
| 824 | if (RTC_IOMAPPED) |
| 825 | r = request_region(RTC_PORT(0), size, "rtc"); |
| 826 | else |
| 827 | r = request_mem_region(RTC_PORT(0), size, "rtc"); |
| 828 | |
| 829 | if (r) |
| 830 | rtc_size = size; |
| 831 | |
| 832 | return r; |
| 833 | } |
| 834 | |
Bjorn Helgaas | 4c06be1 | 2007-11-14 16:59:56 -0800 | [diff] [blame] | 835 | static void rtc_release_region(void) |
| 836 | { |
| 837 | if (RTC_IOMAPPED) |
Bjorn Helgaas | 9626f1f1 | 2007-11-14 16:59:57 -0800 | [diff] [blame] | 838 | release_region(RTC_PORT(0), rtc_size); |
Bjorn Helgaas | 4c06be1 | 2007-11-14 16:59:56 -0800 | [diff] [blame] | 839 | else |
Bjorn Helgaas | 9626f1f1 | 2007-11-14 16:59:57 -0800 | [diff] [blame] | 840 | release_mem_region(RTC_PORT(0), rtc_size); |
Bjorn Helgaas | 4c06be1 | 2007-11-14 16:59:56 -0800 | [diff] [blame] | 841 | } |
| 842 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 843 | static int __init rtc_init(void) |
| 844 | { |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 845 | #ifdef CONFIG_PROC_FS |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 846 | struct proc_dir_entry *ent; |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 847 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 848 | #if defined(__alpha__) || defined(__mips__) |
| 849 | unsigned int year, ctrl; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 850 | char *guess = NULL; |
| 851 | #endif |
David S. Miller | cdee99d | 2007-07-19 13:59:58 -0700 | [diff] [blame] | 852 | #ifdef CONFIG_SPARC32 |
David S. Miller | 7508132 | 2008-08-30 00:23:51 -0700 | [diff] [blame] | 853 | struct device_node *ebus_dp; |
Grant Likely | 2dc1158 | 2010-08-06 09:25:50 -0600 | [diff] [blame] | 854 | struct platform_device *op; |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 855 | #else |
Maciej W. Rozycki | 38e0e8c | 2006-07-10 04:45:30 -0700 | [diff] [blame] | 856 | void *r; |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 857 | #ifdef RTC_IRQ |
| 858 | irq_handler_t rtc_int_handler_ptr; |
| 859 | #endif |
Maciej W. Rozycki | 38e0e8c | 2006-07-10 04:45:30 -0700 | [diff] [blame] | 860 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 861 | |
David S. Miller | cdee99d | 2007-07-19 13:59:58 -0700 | [diff] [blame] | 862 | #ifdef CONFIG_SPARC32 |
David S. Miller | 7508132 | 2008-08-30 00:23:51 -0700 | [diff] [blame] | 863 | for_each_node_by_name(ebus_dp, "ebus") { |
| 864 | struct device_node *dp; |
Rob Herring | f88fd66 | 2018-12-05 13:50:19 -0600 | [diff] [blame] | 865 | for_each_child_of_node(ebus_dp, dp) { |
| 866 | if (of_node_name_eq(dp, "rtc")) { |
David S. Miller | 7508132 | 2008-08-30 00:23:51 -0700 | [diff] [blame] | 867 | op = of_find_device_by_node(dp); |
| 868 | if (op) { |
| 869 | rtc_port = op->resource[0].start; |
| 870 | rtc_irq = op->irqs[0]; |
| 871 | goto found; |
| 872 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 873 | } |
| 874 | } |
| 875 | } |
Jan Beulich | f3e92d3 | 2006-12-13 00:35:04 -0800 | [diff] [blame] | 876 | rtc_has_irq = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 877 | printk(KERN_ERR "rtc_init: no PC rtc found\n"); |
| 878 | return -EIO; |
| 879 | |
| 880 | found: |
David S. Miller | 7508132 | 2008-08-30 00:23:51 -0700 | [diff] [blame] | 881 | if (!rtc_irq) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 882 | rtc_has_irq = 0; |
| 883 | goto no_irq; |
| 884 | } |
| 885 | |
| 886 | /* |
| 887 | * XXX Interrupt pin #7 in Espresso is shared between RTC and |
David S. Miller | 53d0fc2 | 2005-09-05 23:33:05 -0700 | [diff] [blame] | 888 | * PCI Slot 2 INTA# (and some INTx# in Slot 1). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 889 | */ |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 890 | if (request_irq(rtc_irq, rtc_interrupt, IRQF_SHARED, "rtc", |
| 891 | (void *)&rtc_port)) { |
Jan Beulich | f3e92d3 | 2006-12-13 00:35:04 -0800 | [diff] [blame] | 892 | rtc_has_irq = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 893 | printk(KERN_ERR "rtc: cannot register IRQ %d\n", rtc_irq); |
| 894 | return -EIO; |
| 895 | } |
| 896 | no_irq: |
| 897 | #else |
Bjorn Helgaas | 9626f1f1 | 2007-11-14 16:59:57 -0800 | [diff] [blame] | 898 | r = rtc_request_region(RTC_IO_EXTENT); |
| 899 | |
| 900 | /* |
| 901 | * If we've already requested a smaller range (for example, because |
| 902 | * PNPBIOS or ACPI told us how the device is configured), the request |
| 903 | * above might fail because it's too big. |
| 904 | * |
| 905 | * If so, request just the range we actually use. |
| 906 | */ |
| 907 | if (!r) |
| 908 | r = rtc_request_region(RTC_IO_EXTENT_USED); |
Maciej W. Rozycki | 38e0e8c | 2006-07-10 04:45:30 -0700 | [diff] [blame] | 909 | if (!r) { |
Jan Beulich | f3e92d3 | 2006-12-13 00:35:04 -0800 | [diff] [blame] | 910 | #ifdef RTC_IRQ |
| 911 | rtc_has_irq = 0; |
| 912 | #endif |
Maciej W. Rozycki | 38e0e8c | 2006-07-10 04:45:30 -0700 | [diff] [blame] | 913 | printk(KERN_ERR "rtc: I/O resource %lx is not free.\n", |
| 914 | (long)(RTC_PORT(0))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 915 | return -EIO; |
| 916 | } |
| 917 | |
| 918 | #ifdef RTC_IRQ |
| 919 | if (is_hpet_enabled()) { |
Bernhard Walle | f8f7648 | 2008-01-30 13:33:31 +0100 | [diff] [blame] | 920 | int err; |
| 921 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 922 | rtc_int_handler_ptr = hpet_rtc_interrupt; |
Bernhard Walle | f8f7648 | 2008-01-30 13:33:31 +0100 | [diff] [blame] | 923 | err = hpet_register_irq_handler(rtc_interrupt); |
| 924 | if (err != 0) { |
| 925 | printk(KERN_WARNING "hpet_register_irq_handler failed " |
| 926 | "in rtc_init()."); |
| 927 | return err; |
| 928 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 929 | } else { |
| 930 | rtc_int_handler_ptr = rtc_interrupt; |
| 931 | } |
| 932 | |
Michael Opdenacker | d88ed62 | 2013-10-13 06:14:42 +0200 | [diff] [blame] | 933 | if (request_irq(RTC_IRQ, rtc_int_handler_ptr, 0, "rtc", NULL)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 934 | /* Yeah right, seeing as irq 8 doesn't even hit the bus. */ |
Jan Beulich | f3e92d3 | 2006-12-13 00:35:04 -0800 | [diff] [blame] | 935 | rtc_has_irq = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 936 | printk(KERN_ERR "rtc: IRQ %d is not free.\n", RTC_IRQ); |
Bjorn Helgaas | 4c06be1 | 2007-11-14 16:59:56 -0800 | [diff] [blame] | 937 | rtc_release_region(); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 938 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 939 | return -EIO; |
| 940 | } |
| 941 | hpet_rtc_timer_init(); |
| 942 | |
| 943 | #endif |
| 944 | |
David S. Miller | cdee99d | 2007-07-19 13:59:58 -0700 | [diff] [blame] | 945 | #endif /* CONFIG_SPARC32 vs. others */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 946 | |
| 947 | if (misc_register(&rtc_dev)) { |
| 948 | #ifdef RTC_IRQ |
| 949 | free_irq(RTC_IRQ, NULL); |
Bernhard Walle | f8f7648 | 2008-01-30 13:33:31 +0100 | [diff] [blame] | 950 | hpet_unregister_irq_handler(rtc_interrupt); |
Jan Beulich | f3e92d3 | 2006-12-13 00:35:04 -0800 | [diff] [blame] | 951 | rtc_has_irq = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 952 | #endif |
Bjorn Helgaas | 4c06be1 | 2007-11-14 16:59:56 -0800 | [diff] [blame] | 953 | rtc_release_region(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 954 | return -ENODEV; |
| 955 | } |
| 956 | |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 957 | #ifdef CONFIG_PROC_FS |
Christoph Hellwig | 3f3942a | 2018-05-15 15:57:23 +0200 | [diff] [blame] | 958 | ent = proc_create_single("driver/rtc", 0, NULL, rtc_proc_show); |
Denis V. Lunev | 1b50221 | 2008-04-29 01:02:34 -0700 | [diff] [blame] | 959 | if (!ent) |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 960 | printk(KERN_WARNING "rtc: Failed to register with procfs.\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 961 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 962 | |
| 963 | #if defined(__alpha__) || defined(__mips__) |
| 964 | rtc_freq = HZ; |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 965 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 966 | /* Each operating system on an Alpha uses its own epoch. |
| 967 | Let's try to guess which one we are using now. */ |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 968 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 969 | if (rtc_is_updating() != 0) |
Luca Falavigna | 47f176f | 2005-06-28 20:44:42 -0700 | [diff] [blame] | 970 | msleep(20); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 971 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 972 | spin_lock_irq(&rtc_lock); |
| 973 | year = CMOS_READ(RTC_YEAR); |
| 974 | ctrl = CMOS_READ(RTC_CONTROL); |
| 975 | spin_unlock_irq(&rtc_lock); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 976 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 977 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) |
Adrian Bunk | 357c6e6 | 2008-10-18 20:28:42 -0700 | [diff] [blame] | 978 | year = bcd2bin(year); /* This should never happen... */ |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 979 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 980 | if (year < 20) { |
| 981 | epoch = 2000; |
| 982 | guess = "SRM (post-2000)"; |
| 983 | } else if (year >= 20 && year < 48) { |
| 984 | epoch = 1980; |
| 985 | guess = "ARC console"; |
| 986 | } else if (year >= 48 && year < 72) { |
| 987 | epoch = 1952; |
| 988 | guess = "Digital UNIX"; |
| 989 | #if defined(__mips__) |
| 990 | } else if (year >= 72 && year < 74) { |
| 991 | epoch = 2000; |
| 992 | guess = "Digital DECstation"; |
| 993 | #else |
| 994 | } else if (year >= 70) { |
| 995 | epoch = 1900; |
| 996 | guess = "Standard PC (1900)"; |
| 997 | #endif |
| 998 | } |
| 999 | if (guess) |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1000 | printk(KERN_INFO "rtc: %s epoch (%lu) detected\n", |
| 1001 | guess, epoch); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1002 | #endif |
| 1003 | #ifdef RTC_IRQ |
| 1004 | if (rtc_has_irq == 0) |
| 1005 | goto no_irq2; |
| 1006 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1007 | spin_lock_irq(&rtc_lock); |
| 1008 | rtc_freq = 1024; |
| 1009 | if (!hpet_set_periodic_freq(rtc_freq)) { |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1010 | /* |
| 1011 | * Initialize periodic frequency to CMOS reset default, |
| 1012 | * which is 1024Hz |
| 1013 | */ |
| 1014 | CMOS_WRITE(((CMOS_READ(RTC_FREQ_SELECT) & 0xF0) | 0x06), |
| 1015 | RTC_FREQ_SELECT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1016 | } |
| 1017 | spin_unlock_irq(&rtc_lock); |
| 1018 | no_irq2: |
| 1019 | #endif |
| 1020 | |
| 1021 | (void) init_sysctl(); |
| 1022 | |
| 1023 | printk(KERN_INFO "Real Time Clock Driver v" RTC_VERSION "\n"); |
| 1024 | |
| 1025 | return 0; |
| 1026 | } |
| 1027 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1028 | static void __exit rtc_exit(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1029 | { |
| 1030 | cleanup_sysctl(); |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1031 | remove_proc_entry("driver/rtc", NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1032 | misc_deregister(&rtc_dev); |
| 1033 | |
David S. Miller | cdee99d | 2007-07-19 13:59:58 -0700 | [diff] [blame] | 1034 | #ifdef CONFIG_SPARC32 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1035 | if (rtc_has_irq) |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1036 | free_irq(rtc_irq, &rtc_port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1037 | #else |
Bjorn Helgaas | 4c06be1 | 2007-11-14 16:59:56 -0800 | [diff] [blame] | 1038 | rtc_release_region(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1039 | #ifdef RTC_IRQ |
Bernhard Walle | f8f7648 | 2008-01-30 13:33:31 +0100 | [diff] [blame] | 1040 | if (rtc_has_irq) { |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1041 | free_irq(RTC_IRQ, NULL); |
Bernhard Walle | f8f7648 | 2008-01-30 13:33:31 +0100 | [diff] [blame] | 1042 | hpet_unregister_irq_handler(hpet_rtc_interrupt); |
| 1043 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1044 | #endif |
David S. Miller | cdee99d | 2007-07-19 13:59:58 -0700 | [diff] [blame] | 1045 | #endif /* CONFIG_SPARC32 */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1046 | } |
| 1047 | |
| 1048 | module_init(rtc_init); |
| 1049 | module_exit(rtc_exit); |
| 1050 | |
| 1051 | #ifdef RTC_IRQ |
| 1052 | /* |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1053 | * At IRQ rates >= 4096Hz, an interrupt may get lost altogether. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1054 | * (usually during an IDE disk interrupt, with IRQ unmasking off) |
| 1055 | * Since the interrupt handler doesn't get called, the IRQ status |
| 1056 | * byte doesn't get read, and the RTC stops generating interrupts. |
| 1057 | * A timer is set, and will call this function if/when that happens. |
| 1058 | * To get it out of this stalled state, we just read the status. |
| 1059 | * At least a jiffy of interrupts (rtc_freq/HZ) will have been lost. |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1060 | * (You *really* shouldn't be trying to use a non-realtime system |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1061 | * for something that requires a steady > 1KHz signal anyways.) |
| 1062 | */ |
| 1063 | |
Kees Cook | 24ed960 | 2017-08-28 11:28:21 -0700 | [diff] [blame] | 1064 | static void rtc_dropped_irq(struct timer_list *unused) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1065 | { |
| 1066 | unsigned long freq; |
| 1067 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1068 | spin_lock_irq(&rtc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1069 | |
| 1070 | if (hpet_rtc_dropped_irq()) { |
| 1071 | spin_unlock_irq(&rtc_lock); |
| 1072 | return; |
| 1073 | } |
| 1074 | |
| 1075 | /* Just in case someone disabled the timer from behind our back... */ |
| 1076 | if (rtc_status & RTC_TIMER_ON) |
| 1077 | mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100); |
| 1078 | |
| 1079 | rtc_irq_data += ((rtc_freq/HZ)<<8); |
| 1080 | rtc_irq_data &= ~0xff; |
| 1081 | rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0); /* restart */ |
| 1082 | |
| 1083 | freq = rtc_freq; |
| 1084 | |
| 1085 | spin_unlock_irq(&rtc_lock); |
| 1086 | |
Christian Dietrich | a28ee47 | 2011-06-04 17:36:33 +0200 | [diff] [blame] | 1087 | printk_ratelimited(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n", |
| 1088 | freq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1089 | |
| 1090 | /* Now we have new data */ |
| 1091 | wake_up_interruptible(&rtc_wait); |
| 1092 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1093 | kill_fasync(&rtc_async_queue, SIGIO, POLL_IN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1094 | } |
| 1095 | #endif |
| 1096 | |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 1097 | #ifdef CONFIG_PROC_FS |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1098 | /* |
| 1099 | * Info exported via "/proc/driver/rtc". |
| 1100 | */ |
| 1101 | |
| 1102 | static int rtc_proc_show(struct seq_file *seq, void *v) |
| 1103 | { |
| 1104 | #define YN(bit) ((ctrl & bit) ? "yes" : "no") |
| 1105 | #define NY(bit) ((ctrl & bit) ? "no" : "yes") |
| 1106 | struct rtc_time tm; |
| 1107 | unsigned char batt, ctrl; |
| 1108 | unsigned long freq; |
| 1109 | |
| 1110 | spin_lock_irq(&rtc_lock); |
| 1111 | batt = CMOS_READ(RTC_VALID) & RTC_VRT; |
| 1112 | ctrl = CMOS_READ(RTC_CONTROL); |
| 1113 | freq = rtc_freq; |
| 1114 | spin_unlock_irq(&rtc_lock); |
| 1115 | |
| 1116 | |
| 1117 | rtc_get_rtc_time(&tm); |
| 1118 | |
| 1119 | /* |
| 1120 | * There is no way to tell if the luser has the RTC set for local |
| 1121 | * time or for Universal Standard Time (GMT). Probably local though. |
| 1122 | */ |
| 1123 | seq_printf(seq, |
Andy Shevchenko | 5548cbf | 2018-12-04 23:23:12 +0200 | [diff] [blame] | 1124 | "rtc_time\t: %ptRt\n" |
| 1125 | "rtc_date\t: %ptRd\n" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1126 | "rtc_epoch\t: %04lu\n", |
Andy Shevchenko | 5548cbf | 2018-12-04 23:23:12 +0200 | [diff] [blame] | 1127 | &tm, &tm, epoch); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1128 | |
| 1129 | get_rtc_alm_time(&tm); |
| 1130 | |
| 1131 | /* |
| 1132 | * We implicitly assume 24hr mode here. Alarm values >= 0xc0 will |
| 1133 | * match any value for that particular field. Values that are |
| 1134 | * greater than a valid time, but less than 0xc0 shouldn't appear. |
| 1135 | */ |
| 1136 | seq_puts(seq, "alarm\t\t: "); |
| 1137 | if (tm.tm_hour <= 24) |
| 1138 | seq_printf(seq, "%02d:", tm.tm_hour); |
| 1139 | else |
| 1140 | seq_puts(seq, "**:"); |
| 1141 | |
| 1142 | if (tm.tm_min <= 59) |
| 1143 | seq_printf(seq, "%02d:", tm.tm_min); |
| 1144 | else |
| 1145 | seq_puts(seq, "**:"); |
| 1146 | |
| 1147 | if (tm.tm_sec <= 59) |
| 1148 | seq_printf(seq, "%02d\n", tm.tm_sec); |
| 1149 | else |
| 1150 | seq_puts(seq, "**\n"); |
| 1151 | |
| 1152 | seq_printf(seq, |
| 1153 | "DST_enable\t: %s\n" |
| 1154 | "BCD\t\t: %s\n" |
| 1155 | "24hr\t\t: %s\n" |
| 1156 | "square_wave\t: %s\n" |
| 1157 | "alarm_IRQ\t: %s\n" |
| 1158 | "update_IRQ\t: %s\n" |
| 1159 | "periodic_IRQ\t: %s\n" |
| 1160 | "periodic_freq\t: %ld\n" |
| 1161 | "batt_status\t: %s\n", |
| 1162 | YN(RTC_DST_EN), |
| 1163 | NY(RTC_DM_BINARY), |
| 1164 | YN(RTC_24H), |
| 1165 | YN(RTC_SQWE), |
| 1166 | YN(RTC_AIE), |
| 1167 | YN(RTC_UIE), |
| 1168 | YN(RTC_PIE), |
| 1169 | freq, |
| 1170 | batt ? "okay" : "dead"); |
| 1171 | |
| 1172 | return 0; |
| 1173 | #undef YN |
| 1174 | #undef NY |
| 1175 | } |
Jan Beulich | 9cef779 | 2006-12-13 00:35:05 -0800 | [diff] [blame] | 1176 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1177 | |
Adrian Bunk | 9580d85 | 2008-07-25 19:46:25 -0700 | [diff] [blame] | 1178 | static void rtc_get_rtc_time(struct rtc_time *rtc_tm) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1179 | { |
Ingo Molnar | 0f74964 | 2006-07-12 09:03:10 -0700 | [diff] [blame] | 1180 | unsigned long uip_watchdog = jiffies, flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1181 | unsigned char ctrl; |
| 1182 | #ifdef CONFIG_MACH_DECSTATION |
| 1183 | unsigned int real_year; |
| 1184 | #endif |
| 1185 | |
| 1186 | /* |
| 1187 | * read RTC once any update in progress is done. The update |
Luca Falavigna | 47f176f | 2005-06-28 20:44:42 -0700 | [diff] [blame] | 1188 | * can take just over 2ms. We wait 20ms. There is no need to |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1189 | * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP. |
| 1190 | * If you need to know *exactly* when a second has started, enable |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1191 | * periodic update complete interrupts, (via ioctl) and then |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1192 | * immediately read /dev/rtc which will block until you get the IRQ. |
| 1193 | * Once the read clears, read the RTC time (again via ioctl). Easy. |
| 1194 | */ |
| 1195 | |
Julia Lawall | dca03a5 | 2008-04-28 02:11:59 -0700 | [diff] [blame] | 1196 | while (rtc_is_updating() != 0 && |
| 1197 | time_before(jiffies, uip_watchdog + 2*HZ/100)) |
Petr Vandrovec | 403fe5a | 2005-08-05 15:50:07 +0200 | [diff] [blame] | 1198 | cpu_relax(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1199 | |
| 1200 | /* |
| 1201 | * Only the values that we read from the RTC are set. We leave |
Alan Cox | b759958 | 2006-01-11 12:17:32 -0800 | [diff] [blame] | 1202 | * tm_wday, tm_yday and tm_isdst untouched. Note that while the |
| 1203 | * RTC has RTC_DAY_OF_WEEK, we should usually ignore it, as it is |
| 1204 | * only updated by the RTC when initially set to a non-zero value. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1205 | */ |
Ingo Molnar | 0f74964 | 2006-07-12 09:03:10 -0700 | [diff] [blame] | 1206 | spin_lock_irqsave(&rtc_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1207 | rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS); |
| 1208 | rtc_tm->tm_min = CMOS_READ(RTC_MINUTES); |
| 1209 | rtc_tm->tm_hour = CMOS_READ(RTC_HOURS); |
| 1210 | rtc_tm->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH); |
| 1211 | rtc_tm->tm_mon = CMOS_READ(RTC_MONTH); |
| 1212 | rtc_tm->tm_year = CMOS_READ(RTC_YEAR); |
Alan Cox | b759958 | 2006-01-11 12:17:32 -0800 | [diff] [blame] | 1213 | /* Only set from 2.6.16 onwards */ |
| 1214 | rtc_tm->tm_wday = CMOS_READ(RTC_DAY_OF_WEEK); |
| 1215 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1216 | #ifdef CONFIG_MACH_DECSTATION |
| 1217 | real_year = CMOS_READ(RTC_DEC_YEAR); |
| 1218 | #endif |
| 1219 | ctrl = CMOS_READ(RTC_CONTROL); |
Ingo Molnar | 0f74964 | 2006-07-12 09:03:10 -0700 | [diff] [blame] | 1220 | spin_unlock_irqrestore(&rtc_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1221 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1222 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { |
Adrian Bunk | 357c6e6 | 2008-10-18 20:28:42 -0700 | [diff] [blame] | 1223 | rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec); |
| 1224 | rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min); |
| 1225 | rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour); |
| 1226 | rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday); |
| 1227 | rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon); |
| 1228 | rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year); |
| 1229 | rtc_tm->tm_wday = bcd2bin(rtc_tm->tm_wday); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1230 | } |
| 1231 | |
| 1232 | #ifdef CONFIG_MACH_DECSTATION |
| 1233 | rtc_tm->tm_year += real_year - 72; |
| 1234 | #endif |
| 1235 | |
| 1236 | /* |
| 1237 | * Account for differences between how the RTC uses the values |
| 1238 | * and how they are defined in a struct rtc_time; |
| 1239 | */ |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1240 | rtc_tm->tm_year += epoch - 1900; |
| 1241 | if (rtc_tm->tm_year <= 69) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1242 | rtc_tm->tm_year += 100; |
| 1243 | |
| 1244 | rtc_tm->tm_mon--; |
| 1245 | } |
| 1246 | |
| 1247 | static void get_rtc_alm_time(struct rtc_time *alm_tm) |
| 1248 | { |
| 1249 | unsigned char ctrl; |
| 1250 | |
| 1251 | /* |
| 1252 | * Only the values that we read from the RTC are set. That |
| 1253 | * means only tm_hour, tm_min, and tm_sec. |
| 1254 | */ |
| 1255 | spin_lock_irq(&rtc_lock); |
| 1256 | alm_tm->tm_sec = CMOS_READ(RTC_SECONDS_ALARM); |
| 1257 | alm_tm->tm_min = CMOS_READ(RTC_MINUTES_ALARM); |
| 1258 | alm_tm->tm_hour = CMOS_READ(RTC_HOURS_ALARM); |
| 1259 | ctrl = CMOS_READ(RTC_CONTROL); |
| 1260 | spin_unlock_irq(&rtc_lock); |
| 1261 | |
Ingo Molnar | 5fd1fe9 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1262 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { |
Adrian Bunk | 357c6e6 | 2008-10-18 20:28:42 -0700 | [diff] [blame] | 1263 | alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec); |
| 1264 | alm_tm->tm_min = bcd2bin(alm_tm->tm_min); |
| 1265 | alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1266 | } |
| 1267 | } |
| 1268 | |
| 1269 | #ifdef RTC_IRQ |
| 1270 | /* |
| 1271 | * Used to disable/enable interrupts for any one of UIE, AIE, PIE. |
| 1272 | * Rumour has it that if you frob the interrupt enable/disable |
| 1273 | * bits in RTC_CONTROL, you should read RTC_INTR_FLAGS, to |
| 1274 | * ensure you actually start getting interrupts. Probably for |
| 1275 | * compatibility with older/broken chipset RTC implementations. |
| 1276 | * We also clear out any old irq data after an ioctl() that |
| 1277 | * meddles with the interrupt enable/disable bits. |
| 1278 | */ |
| 1279 | |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 1280 | static void mask_rtc_irq_bit_locked(unsigned char bit) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1281 | { |
| 1282 | unsigned char val; |
| 1283 | |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 1284 | if (hpet_mask_rtc_irq_bit(bit)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1285 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1286 | val = CMOS_READ(RTC_CONTROL); |
| 1287 | val &= ~bit; |
| 1288 | CMOS_WRITE(val, RTC_CONTROL); |
| 1289 | CMOS_READ(RTC_INTR_FLAGS); |
| 1290 | |
| 1291 | rtc_irq_data = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1292 | } |
| 1293 | |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 1294 | static void set_rtc_irq_bit_locked(unsigned char bit) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1295 | { |
| 1296 | unsigned char val; |
| 1297 | |
Takashi Iwai | c334876 | 2005-11-07 11:14:57 +0100 | [diff] [blame] | 1298 | if (hpet_set_rtc_irq_bit(bit)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1299 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1300 | val = CMOS_READ(RTC_CONTROL); |
| 1301 | val |= bit; |
| 1302 | CMOS_WRITE(val, RTC_CONTROL); |
| 1303 | CMOS_READ(RTC_INTR_FLAGS); |
| 1304 | |
| 1305 | rtc_irq_data = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1306 | } |
| 1307 | #endif |
| 1308 | |
| 1309 | MODULE_AUTHOR("Paul Gortmaker"); |
| 1310 | MODULE_LICENSE("GPL"); |
| 1311 | MODULE_ALIAS_MISCDEV(RTC_MINOR); |