![Ingo Molnar](/assets/img/avatar_default.png)
Joseph Fannin reported that hpet_rtc_interrupt() enables hardirqs in irq context: [ 25.628000] [<c014af4e>] trace_hardirqs_on+0xce/0x200 [ 25.628000] [<c036cf21>] _spin_unlock_irq+0x31/0x70 [ 25.628000] [<c0296584>] rtc_get_rtc_time+0x44/0x1a0 [ 25.628000] [<c01198bb>] hpet_rtc_interrupt+0x21b/0x280 [ 25.628000] [<c0161141>] handle_IRQ_event+0x31/0x70 [ 25.628000] [<c0162d37>] handle_edge_irq+0xe7/0x210 [ 25.628000] [<c0106192>] do_IRQ+0x92/0x120 [ 25.628000] [<c0104121>] common_interrupt+0x25/0x2c the call of rtc_get_rtc_time() is highly suspect. At a minimum we need the patch below to save/restore hardirq state. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Joseph Fannin <jfannin@gmail.com> Cc: John Stultz <johnstul@us.ibm.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1382 lines
33 KiB
C
1382 lines
33 KiB
C
/*
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* Real Time Clock interface for Linux
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*
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* Copyright (C) 1996 Paul Gortmaker
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*
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* This driver allows use of the real time clock (built into
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* nearly all computers) from user space. It exports the /dev/rtc
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* interface supporting various ioctl() and also the
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* /proc/driver/rtc pseudo-file for status information.
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*
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* The ioctls can be used to set the interrupt behaviour and
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* generation rate from the RTC via IRQ 8. Then the /dev/rtc
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* interface can be used to make use of these timer interrupts,
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* be they interval or alarm based.
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*
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* The /dev/rtc interface will block on reads until an interrupt
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* has been received. If a RTC interrupt has already happened,
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* it will output an unsigned long and then block. The output value
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* contains the interrupt status in the low byte and the number of
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* interrupts since the last read in the remaining high bytes. The
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* /dev/rtc interface can also be used with the select(2) call.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Based on other minimal char device drivers, like Alan's
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* watchdog, Ted's random, etc. etc.
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*
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* 1.07 Paul Gortmaker.
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* 1.08 Miquel van Smoorenburg: disallow certain things on the
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* DEC Alpha as the CMOS clock is also used for other things.
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* 1.09 Nikita Schmidt: epoch support and some Alpha cleanup.
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* 1.09a Pete Zaitcev: Sun SPARC
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* 1.09b Jeff Garzik: Modularize, init cleanup
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* 1.09c Jeff Garzik: SMP cleanup
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* 1.10 Paul Barton-Davis: add support for async I/O
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* 1.10a Andrea Arcangeli: Alpha updates
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* 1.10b Andrew Morton: SMP lock fix
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* 1.10c Cesar Barros: SMP locking fixes and cleanup
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* 1.10d Paul Gortmaker: delete paranoia check in rtc_exit
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* 1.10e Maciej W. Rozycki: Handle DECstation's year weirdness.
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* 1.11 Takashi Iwai: Kernel access functions
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* rtc_register/rtc_unregister/rtc_control
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* 1.11a Daniele Bellucci: Audit create_proc_read_entry in rtc_init
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* 1.12 Venkatesh Pallipadi: Hooks for emulating rtc on HPET base-timer
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* CONFIG_HPET_EMULATE_RTC
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* 1.12a Maciej W. Rozycki: Handle memory-mapped chips properly.
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* 1.12ac Alan Cox: Allow read access to the day of week register
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*/
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#define RTC_VERSION "1.12ac"
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/*
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* Note that *all* calls to CMOS_READ and CMOS_WRITE are done with
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* interrupts disabled. Due to the index-port/data-port (0x70/0x71)
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* design of the RTC, we don't want two different things trying to
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* get to it at once. (e.g. the periodic 11 min sync from time.c vs.
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* this driver.)
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*/
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#include <linux/interrupt.h>
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/types.h>
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#include <linux/miscdevice.h>
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#include <linux/ioport.h>
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#include <linux/fcntl.h>
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#include <linux/mc146818rtc.h>
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#include <linux/init.h>
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#include <linux/poll.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/spinlock.h>
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#include <linux/sysctl.h>
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#include <linux/wait.h>
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#include <linux/bcd.h>
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#include <linux/delay.h>
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#include <asm/current.h>
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#include <asm/uaccess.h>
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#include <asm/system.h>
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#if defined(__i386__)
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#include <asm/hpet.h>
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#endif
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#ifdef __sparc__
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#include <linux/pci.h>
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#include <asm/ebus.h>
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#ifdef __sparc_v9__
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#include <asm/isa.h>
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#endif
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static unsigned long rtc_port;
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static int rtc_irq = PCI_IRQ_NONE;
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#endif
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#ifdef CONFIG_HPET_RTC_IRQ
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#undef RTC_IRQ
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#endif
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#ifdef RTC_IRQ
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static int rtc_has_irq = 1;
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#endif
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#ifndef CONFIG_HPET_EMULATE_RTC
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#define is_hpet_enabled() 0
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#define hpet_set_alarm_time(hrs, min, sec) 0
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#define hpet_set_periodic_freq(arg) 0
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#define hpet_mask_rtc_irq_bit(arg) 0
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#define hpet_set_rtc_irq_bit(arg) 0
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#define hpet_rtc_timer_init() do { } while (0)
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#define hpet_rtc_dropped_irq() 0
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static inline irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs) {return 0;}
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#else
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extern irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs);
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#endif
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/*
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* We sponge a minor off of the misc major. No need slurping
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* up another valuable major dev number for this. If you add
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* an ioctl, make sure you don't conflict with SPARC's RTC
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* ioctls.
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*/
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static struct fasync_struct *rtc_async_queue;
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static DECLARE_WAIT_QUEUE_HEAD(rtc_wait);
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#ifdef RTC_IRQ
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static struct timer_list rtc_irq_timer;
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#endif
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static ssize_t rtc_read(struct file *file, char __user *buf,
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size_t count, loff_t *ppos);
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static int rtc_ioctl(struct inode *inode, struct file *file,
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unsigned int cmd, unsigned long arg);
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#ifdef RTC_IRQ
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static unsigned int rtc_poll(struct file *file, poll_table *wait);
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#endif
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static void get_rtc_alm_time (struct rtc_time *alm_tm);
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#ifdef RTC_IRQ
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static void rtc_dropped_irq(unsigned long data);
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static void set_rtc_irq_bit_locked(unsigned char bit);
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static void mask_rtc_irq_bit_locked(unsigned char bit);
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static inline void set_rtc_irq_bit(unsigned char bit)
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{
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spin_lock_irq(&rtc_lock);
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set_rtc_irq_bit_locked(bit);
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spin_unlock_irq(&rtc_lock);
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}
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static void mask_rtc_irq_bit(unsigned char bit)
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{
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spin_lock_irq(&rtc_lock);
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mask_rtc_irq_bit_locked(bit);
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spin_unlock_irq(&rtc_lock);
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}
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#endif
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static int rtc_proc_open(struct inode *inode, struct file *file);
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/*
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* Bits in rtc_status. (6 bits of room for future expansion)
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*/
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#define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */
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#define RTC_TIMER_ON 0x02 /* missed irq timer active */
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/*
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* rtc_status is never changed by rtc_interrupt, and ioctl/open/close is
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* protected by the big kernel lock. However, ioctl can still disable the timer
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* in rtc_status and then with del_timer after the interrupt has read
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* rtc_status but before mod_timer is called, which would then reenable the
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* timer (but you would need to have an awful timing before you'd trip on it)
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*/
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static unsigned long rtc_status = 0; /* bitmapped status byte. */
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static unsigned long rtc_freq = 0; /* Current periodic IRQ rate */
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static unsigned long rtc_irq_data = 0; /* our output to the world */
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static unsigned long rtc_max_user_freq = 64; /* > this, need CAP_SYS_RESOURCE */
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#ifdef RTC_IRQ
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/*
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* rtc_task_lock nests inside rtc_lock.
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*/
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static DEFINE_SPINLOCK(rtc_task_lock);
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static rtc_task_t *rtc_callback = NULL;
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#endif
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/*
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* If this driver ever becomes modularised, it will be really nice
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* to make the epoch retain its value across module reload...
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*/
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static unsigned long epoch = 1900; /* year corresponding to 0x00 */
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static const unsigned char days_in_mo[] =
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{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
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/*
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* Returns true if a clock update is in progress
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*/
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static inline unsigned char rtc_is_updating(void)
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{
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unsigned char uip;
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spin_lock_irq(&rtc_lock);
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uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP);
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spin_unlock_irq(&rtc_lock);
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return uip;
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}
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#ifdef RTC_IRQ
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/*
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* A very tiny interrupt handler. It runs with IRQF_DISABLED set,
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* but there is possibility of conflicting with the set_rtc_mmss()
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* call (the rtc irq and the timer irq can easily run at the same
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* time in two different CPUs). So we need to serialize
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* accesses to the chip with the rtc_lock spinlock that each
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* architecture should implement in the timer code.
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* (See ./arch/XXXX/kernel/time.c for the set_rtc_mmss() function.)
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*/
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irqreturn_t rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
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{
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/*
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* Can be an alarm interrupt, update complete interrupt,
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* or a periodic interrupt. We store the status in the
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* low byte and the number of interrupts received since
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* the last read in the remainder of rtc_irq_data.
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*/
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spin_lock (&rtc_lock);
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rtc_irq_data += 0x100;
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rtc_irq_data &= ~0xff;
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if (is_hpet_enabled()) {
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/*
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* In this case it is HPET RTC interrupt handler
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* calling us, with the interrupt information
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* passed as arg1, instead of irq.
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*/
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rtc_irq_data |= (unsigned long)irq & 0xF0;
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} else {
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rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0);
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}
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if (rtc_status & RTC_TIMER_ON)
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mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100);
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spin_unlock (&rtc_lock);
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/* Now do the rest of the actions */
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spin_lock(&rtc_task_lock);
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if (rtc_callback)
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rtc_callback->func(rtc_callback->private_data);
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spin_unlock(&rtc_task_lock);
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wake_up_interruptible(&rtc_wait);
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kill_fasync (&rtc_async_queue, SIGIO, POLL_IN);
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return IRQ_HANDLED;
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}
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#endif
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/*
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* sysctl-tuning infrastructure.
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*/
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static ctl_table rtc_table[] = {
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{
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.ctl_name = 1,
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.procname = "max-user-freq",
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.data = &rtc_max_user_freq,
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.maxlen = sizeof(int),
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.mode = 0644,
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.proc_handler = &proc_dointvec,
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},
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{ .ctl_name = 0 }
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};
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static ctl_table rtc_root[] = {
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{
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.ctl_name = 1,
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.procname = "rtc",
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.maxlen = 0,
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.mode = 0555,
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.child = rtc_table,
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},
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{ .ctl_name = 0 }
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};
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static ctl_table dev_root[] = {
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{
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.ctl_name = CTL_DEV,
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.procname = "dev",
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.maxlen = 0,
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.mode = 0555,
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.child = rtc_root,
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},
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{ .ctl_name = 0 }
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};
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static struct ctl_table_header *sysctl_header;
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static int __init init_sysctl(void)
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{
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sysctl_header = register_sysctl_table(dev_root, 0);
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return 0;
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}
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static void __exit cleanup_sysctl(void)
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{
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unregister_sysctl_table(sysctl_header);
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}
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/*
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* Now all the various file operations that we export.
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*/
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static ssize_t rtc_read(struct file *file, char __user *buf,
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size_t count, loff_t *ppos)
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{
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#ifndef RTC_IRQ
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return -EIO;
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#else
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DECLARE_WAITQUEUE(wait, current);
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unsigned long data;
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ssize_t retval;
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if (rtc_has_irq == 0)
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return -EIO;
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/*
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* Historically this function used to assume that sizeof(unsigned long)
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* is the same in userspace and kernelspace. This lead to problems
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* for configurations with multiple ABIs such a the MIPS o32 and 64
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* ABIs supported on the same kernel. So now we support read of both
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* 4 and 8 bytes and assume that's the sizeof(unsigned long) in the
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* userspace ABI.
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*/
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if (count != sizeof(unsigned int) && count != sizeof(unsigned long))
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return -EINVAL;
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add_wait_queue(&rtc_wait, &wait);
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do {
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/* First make it right. Then make it fast. Putting this whole
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* block within the parentheses of a while would be too
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* confusing. And no, xchg() is not the answer. */
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__set_current_state(TASK_INTERRUPTIBLE);
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spin_lock_irq (&rtc_lock);
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data = rtc_irq_data;
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rtc_irq_data = 0;
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spin_unlock_irq (&rtc_lock);
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if (data != 0)
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break;
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if (file->f_flags & O_NONBLOCK) {
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retval = -EAGAIN;
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goto out;
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}
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if (signal_pending(current)) {
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retval = -ERESTARTSYS;
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goto out;
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}
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schedule();
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} while (1);
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if (count == sizeof(unsigned int))
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retval = put_user(data, (unsigned int __user *)buf) ?: sizeof(int);
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else
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retval = put_user(data, (unsigned long __user *)buf) ?: sizeof(long);
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if (!retval)
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retval = count;
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out:
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current->state = TASK_RUNNING;
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remove_wait_queue(&rtc_wait, &wait);
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return retval;
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#endif
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}
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static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel)
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{
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struct rtc_time wtime;
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#ifdef RTC_IRQ
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if (rtc_has_irq == 0) {
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switch (cmd) {
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case RTC_AIE_OFF:
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case RTC_AIE_ON:
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case RTC_PIE_OFF:
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case RTC_PIE_ON:
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case RTC_UIE_OFF:
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case RTC_UIE_ON:
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case RTC_IRQP_READ:
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case RTC_IRQP_SET:
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return -EINVAL;
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};
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}
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#endif
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switch (cmd) {
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#ifdef RTC_IRQ
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case RTC_AIE_OFF: /* Mask alarm int. enab. bit */
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{
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mask_rtc_irq_bit(RTC_AIE);
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return 0;
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}
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case RTC_AIE_ON: /* Allow alarm interrupts. */
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{
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set_rtc_irq_bit(RTC_AIE);
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return 0;
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}
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case RTC_PIE_OFF: /* Mask periodic int. enab. bit */
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{
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unsigned long flags; /* can be called from isr via rtc_control() */
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spin_lock_irqsave (&rtc_lock, flags);
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mask_rtc_irq_bit_locked(RTC_PIE);
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if (rtc_status & RTC_TIMER_ON) {
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rtc_status &= ~RTC_TIMER_ON;
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del_timer(&rtc_irq_timer);
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}
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spin_unlock_irqrestore (&rtc_lock, flags);
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return 0;
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}
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case RTC_PIE_ON: /* Allow periodic ints */
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{
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unsigned long flags; /* can be called from isr via rtc_control() */
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/*
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* We don't really want Joe User enabling more
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* than 64Hz of interrupts on a multi-user machine.
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*/
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if (!kernel && (rtc_freq > rtc_max_user_freq) &&
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(!capable(CAP_SYS_RESOURCE)))
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return -EACCES;
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spin_lock_irqsave (&rtc_lock, flags);
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if (!(rtc_status & RTC_TIMER_ON)) {
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rtc_irq_timer.expires = jiffies + HZ/rtc_freq + 2*HZ/100;
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add_timer(&rtc_irq_timer);
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rtc_status |= RTC_TIMER_ON;
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}
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set_rtc_irq_bit_locked(RTC_PIE);
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spin_unlock_irqrestore (&rtc_lock, flags);
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return 0;
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}
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case RTC_UIE_OFF: /* Mask ints from RTC updates. */
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{
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mask_rtc_irq_bit(RTC_UIE);
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return 0;
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}
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case RTC_UIE_ON: /* Allow ints for RTC updates. */
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{
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set_rtc_irq_bit(RTC_UIE);
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return 0;
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}
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#endif
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case RTC_ALM_READ: /* Read the present alarm time */
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{
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/*
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* This returns a struct rtc_time. Reading >= 0xc0
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* means "don't care" or "match all". Only the tm_hour,
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* tm_min, and tm_sec values are filled in.
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*/
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memset(&wtime, 0, sizeof(struct rtc_time));
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get_rtc_alm_time(&wtime);
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break;
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}
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case RTC_ALM_SET: /* Store a time into the alarm */
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{
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/*
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* This expects a struct rtc_time. Writing 0xff means
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* "don't care" or "match all". Only the tm_hour,
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* tm_min and tm_sec are used.
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*/
|
|
unsigned char hrs, min, sec;
|
|
struct rtc_time alm_tm;
|
|
|
|
if (copy_from_user(&alm_tm, (struct rtc_time __user *)arg,
|
|
sizeof(struct rtc_time)))
|
|
return -EFAULT;
|
|
|
|
hrs = alm_tm.tm_hour;
|
|
min = alm_tm.tm_min;
|
|
sec = alm_tm.tm_sec;
|
|
|
|
spin_lock_irq(&rtc_lock);
|
|
if (hpet_set_alarm_time(hrs, min, sec)) {
|
|
/*
|
|
* Fallthru and set alarm time in CMOS too,
|
|
* so that we will get proper value in RTC_ALM_READ
|
|
*/
|
|
}
|
|
if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) ||
|
|
RTC_ALWAYS_BCD)
|
|
{
|
|
if (sec < 60) BIN_TO_BCD(sec);
|
|
else sec = 0xff;
|
|
|
|
if (min < 60) BIN_TO_BCD(min);
|
|
else min = 0xff;
|
|
|
|
if (hrs < 24) BIN_TO_BCD(hrs);
|
|
else hrs = 0xff;
|
|
}
|
|
CMOS_WRITE(hrs, RTC_HOURS_ALARM);
|
|
CMOS_WRITE(min, RTC_MINUTES_ALARM);
|
|
CMOS_WRITE(sec, RTC_SECONDS_ALARM);
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
return 0;
|
|
}
|
|
case RTC_RD_TIME: /* Read the time/date from RTC */
|
|
{
|
|
memset(&wtime, 0, sizeof(struct rtc_time));
|
|
rtc_get_rtc_time(&wtime);
|
|
break;
|
|
}
|
|
case RTC_SET_TIME: /* Set the RTC */
|
|
{
|
|
struct rtc_time rtc_tm;
|
|
unsigned char mon, day, hrs, min, sec, leap_yr;
|
|
unsigned char save_control, save_freq_select;
|
|
unsigned int yrs;
|
|
#ifdef CONFIG_MACH_DECSTATION
|
|
unsigned int real_yrs;
|
|
#endif
|
|
|
|
if (!capable(CAP_SYS_TIME))
|
|
return -EACCES;
|
|
|
|
if (copy_from_user(&rtc_tm, (struct rtc_time __user *)arg,
|
|
sizeof(struct rtc_time)))
|
|
return -EFAULT;
|
|
|
|
yrs = rtc_tm.tm_year + 1900;
|
|
mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
|
|
day = rtc_tm.tm_mday;
|
|
hrs = rtc_tm.tm_hour;
|
|
min = rtc_tm.tm_min;
|
|
sec = rtc_tm.tm_sec;
|
|
|
|
if (yrs < 1970)
|
|
return -EINVAL;
|
|
|
|
leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
|
|
|
|
if ((mon > 12) || (day == 0))
|
|
return -EINVAL;
|
|
|
|
if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
|
|
return -EINVAL;
|
|
|
|
if ((hrs >= 24) || (min >= 60) || (sec >= 60))
|
|
return -EINVAL;
|
|
|
|
if ((yrs -= epoch) > 255) /* They are unsigned */
|
|
return -EINVAL;
|
|
|
|
spin_lock_irq(&rtc_lock);
|
|
#ifdef CONFIG_MACH_DECSTATION
|
|
real_yrs = yrs;
|
|
yrs = 72;
|
|
|
|
/*
|
|
* We want to keep the year set to 73 until March
|
|
* for non-leap years, so that Feb, 29th is handled
|
|
* correctly.
|
|
*/
|
|
if (!leap_yr && mon < 3) {
|
|
real_yrs--;
|
|
yrs = 73;
|
|
}
|
|
#endif
|
|
/* These limits and adjustments are independent of
|
|
* whether the chip is in binary mode or not.
|
|
*/
|
|
if (yrs > 169) {
|
|
spin_unlock_irq(&rtc_lock);
|
|
return -EINVAL;
|
|
}
|
|
if (yrs >= 100)
|
|
yrs -= 100;
|
|
|
|
if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY)
|
|
|| RTC_ALWAYS_BCD) {
|
|
BIN_TO_BCD(sec);
|
|
BIN_TO_BCD(min);
|
|
BIN_TO_BCD(hrs);
|
|
BIN_TO_BCD(day);
|
|
BIN_TO_BCD(mon);
|
|
BIN_TO_BCD(yrs);
|
|
}
|
|
|
|
save_control = CMOS_READ(RTC_CONTROL);
|
|
CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL);
|
|
save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
|
|
CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
|
|
|
|
#ifdef CONFIG_MACH_DECSTATION
|
|
CMOS_WRITE(real_yrs, RTC_DEC_YEAR);
|
|
#endif
|
|
CMOS_WRITE(yrs, RTC_YEAR);
|
|
CMOS_WRITE(mon, RTC_MONTH);
|
|
CMOS_WRITE(day, RTC_DAY_OF_MONTH);
|
|
CMOS_WRITE(hrs, RTC_HOURS);
|
|
CMOS_WRITE(min, RTC_MINUTES);
|
|
CMOS_WRITE(sec, RTC_SECONDS);
|
|
|
|
CMOS_WRITE(save_control, RTC_CONTROL);
|
|
CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
|
|
|
|
spin_unlock_irq(&rtc_lock);
|
|
return 0;
|
|
}
|
|
#ifdef RTC_IRQ
|
|
case RTC_IRQP_READ: /* Read the periodic IRQ rate. */
|
|
{
|
|
return put_user(rtc_freq, (unsigned long __user *)arg);
|
|
}
|
|
case RTC_IRQP_SET: /* Set periodic IRQ rate. */
|
|
{
|
|
int tmp = 0;
|
|
unsigned char val;
|
|
unsigned long flags; /* can be called from isr via rtc_control() */
|
|
|
|
/*
|
|
* The max we can do is 8192Hz.
|
|
*/
|
|
if ((arg < 2) || (arg > 8192))
|
|
return -EINVAL;
|
|
/*
|
|
* We don't really want Joe User generating more
|
|
* than 64Hz of interrupts on a multi-user machine.
|
|
*/
|
|
if (!kernel && (arg > rtc_max_user_freq) && (!capable(CAP_SYS_RESOURCE)))
|
|
return -EACCES;
|
|
|
|
while (arg > (1<<tmp))
|
|
tmp++;
|
|
|
|
/*
|
|
* Check that the input was really a power of 2.
|
|
*/
|
|
if (arg != (1<<tmp))
|
|
return -EINVAL;
|
|
|
|
spin_lock_irqsave(&rtc_lock, flags);
|
|
if (hpet_set_periodic_freq(arg)) {
|
|
spin_unlock_irqrestore(&rtc_lock, flags);
|
|
return 0;
|
|
}
|
|
rtc_freq = arg;
|
|
|
|
val = CMOS_READ(RTC_FREQ_SELECT) & 0xf0;
|
|
val |= (16 - tmp);
|
|
CMOS_WRITE(val, RTC_FREQ_SELECT);
|
|
spin_unlock_irqrestore(&rtc_lock, flags);
|
|
return 0;
|
|
}
|
|
#endif
|
|
case RTC_EPOCH_READ: /* Read the epoch. */
|
|
{
|
|
return put_user (epoch, (unsigned long __user *)arg);
|
|
}
|
|
case RTC_EPOCH_SET: /* Set the epoch. */
|
|
{
|
|
/*
|
|
* There were no RTC clocks before 1900.
|
|
*/
|
|
if (arg < 1900)
|
|
return -EINVAL;
|
|
|
|
if (!capable(CAP_SYS_TIME))
|
|
return -EACCES;
|
|
|
|
epoch = arg;
|
|
return 0;
|
|
}
|
|
default:
|
|
return -ENOTTY;
|
|
}
|
|
return copy_to_user((void __user *)arg, &wtime, sizeof wtime) ? -EFAULT : 0;
|
|
}
|
|
|
|
static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
return rtc_do_ioctl(cmd, arg, 0);
|
|
}
|
|
|
|
/*
|
|
* We enforce only one user at a time here with the open/close.
|
|
* Also clear the previous interrupt data on an open, and clean
|
|
* up things on a close.
|
|
*/
|
|
|
|
/* We use rtc_lock to protect against concurrent opens. So the BKL is not
|
|
* needed here. Or anywhere else in this driver. */
|
|
static int rtc_open(struct inode *inode, struct file *file)
|
|
{
|
|
spin_lock_irq (&rtc_lock);
|
|
|
|
if(rtc_status & RTC_IS_OPEN)
|
|
goto out_busy;
|
|
|
|
rtc_status |= RTC_IS_OPEN;
|
|
|
|
rtc_irq_data = 0;
|
|
spin_unlock_irq (&rtc_lock);
|
|
return 0;
|
|
|
|
out_busy:
|
|
spin_unlock_irq (&rtc_lock);
|
|
return -EBUSY;
|
|
}
|
|
|
|
static int rtc_fasync (int fd, struct file *filp, int on)
|
|
|
|
{
|
|
return fasync_helper (fd, filp, on, &rtc_async_queue);
|
|
}
|
|
|
|
static int rtc_release(struct inode *inode, struct file *file)
|
|
{
|
|
#ifdef RTC_IRQ
|
|
unsigned char tmp;
|
|
|
|
if (rtc_has_irq == 0)
|
|
goto no_irq;
|
|
|
|
/*
|
|
* Turn off all interrupts once the device is no longer
|
|
* in use, and clear the data.
|
|
*/
|
|
|
|
spin_lock_irq(&rtc_lock);
|
|
if (!hpet_mask_rtc_irq_bit(RTC_PIE | RTC_AIE | RTC_UIE)) {
|
|
tmp = CMOS_READ(RTC_CONTROL);
|
|
tmp &= ~RTC_PIE;
|
|
tmp &= ~RTC_AIE;
|
|
tmp &= ~RTC_UIE;
|
|
CMOS_WRITE(tmp, RTC_CONTROL);
|
|
CMOS_READ(RTC_INTR_FLAGS);
|
|
}
|
|
if (rtc_status & RTC_TIMER_ON) {
|
|
rtc_status &= ~RTC_TIMER_ON;
|
|
del_timer(&rtc_irq_timer);
|
|
}
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
if (file->f_flags & FASYNC) {
|
|
rtc_fasync (-1, file, 0);
|
|
}
|
|
no_irq:
|
|
#endif
|
|
|
|
spin_lock_irq (&rtc_lock);
|
|
rtc_irq_data = 0;
|
|
rtc_status &= ~RTC_IS_OPEN;
|
|
spin_unlock_irq (&rtc_lock);
|
|
return 0;
|
|
}
|
|
|
|
#ifdef RTC_IRQ
|
|
/* Called without the kernel lock - fine */
|
|
static unsigned int rtc_poll(struct file *file, poll_table *wait)
|
|
{
|
|
unsigned long l;
|
|
|
|
if (rtc_has_irq == 0)
|
|
return 0;
|
|
|
|
poll_wait(file, &rtc_wait, wait);
|
|
|
|
spin_lock_irq (&rtc_lock);
|
|
l = rtc_irq_data;
|
|
spin_unlock_irq (&rtc_lock);
|
|
|
|
if (l != 0)
|
|
return POLLIN | POLLRDNORM;
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* exported stuffs
|
|
*/
|
|
|
|
EXPORT_SYMBOL(rtc_register);
|
|
EXPORT_SYMBOL(rtc_unregister);
|
|
EXPORT_SYMBOL(rtc_control);
|
|
|
|
int rtc_register(rtc_task_t *task)
|
|
{
|
|
#ifndef RTC_IRQ
|
|
return -EIO;
|
|
#else
|
|
if (task == NULL || task->func == NULL)
|
|
return -EINVAL;
|
|
spin_lock_irq(&rtc_lock);
|
|
if (rtc_status & RTC_IS_OPEN) {
|
|
spin_unlock_irq(&rtc_lock);
|
|
return -EBUSY;
|
|
}
|
|
spin_lock(&rtc_task_lock);
|
|
if (rtc_callback) {
|
|
spin_unlock(&rtc_task_lock);
|
|
spin_unlock_irq(&rtc_lock);
|
|
return -EBUSY;
|
|
}
|
|
rtc_status |= RTC_IS_OPEN;
|
|
rtc_callback = task;
|
|
spin_unlock(&rtc_task_lock);
|
|
spin_unlock_irq(&rtc_lock);
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
int rtc_unregister(rtc_task_t *task)
|
|
{
|
|
#ifndef RTC_IRQ
|
|
return -EIO;
|
|
#else
|
|
unsigned char tmp;
|
|
|
|
spin_lock_irq(&rtc_lock);
|
|
spin_lock(&rtc_task_lock);
|
|
if (rtc_callback != task) {
|
|
spin_unlock(&rtc_task_lock);
|
|
spin_unlock_irq(&rtc_lock);
|
|
return -ENXIO;
|
|
}
|
|
rtc_callback = NULL;
|
|
|
|
/* disable controls */
|
|
if (!hpet_mask_rtc_irq_bit(RTC_PIE | RTC_AIE | RTC_UIE)) {
|
|
tmp = CMOS_READ(RTC_CONTROL);
|
|
tmp &= ~RTC_PIE;
|
|
tmp &= ~RTC_AIE;
|
|
tmp &= ~RTC_UIE;
|
|
CMOS_WRITE(tmp, RTC_CONTROL);
|
|
CMOS_READ(RTC_INTR_FLAGS);
|
|
}
|
|
if (rtc_status & RTC_TIMER_ON) {
|
|
rtc_status &= ~RTC_TIMER_ON;
|
|
del_timer(&rtc_irq_timer);
|
|
}
|
|
rtc_status &= ~RTC_IS_OPEN;
|
|
spin_unlock(&rtc_task_lock);
|
|
spin_unlock_irq(&rtc_lock);
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
int rtc_control(rtc_task_t *task, unsigned int cmd, unsigned long arg)
|
|
{
|
|
#ifndef RTC_IRQ
|
|
return -EIO;
|
|
#else
|
|
unsigned long flags;
|
|
if (cmd != RTC_PIE_ON && cmd != RTC_PIE_OFF && cmd != RTC_IRQP_SET)
|
|
return -EINVAL;
|
|
spin_lock_irqsave(&rtc_task_lock, flags);
|
|
if (rtc_callback != task) {
|
|
spin_unlock_irqrestore(&rtc_task_lock, flags);
|
|
return -ENXIO;
|
|
}
|
|
spin_unlock_irqrestore(&rtc_task_lock, flags);
|
|
return rtc_do_ioctl(cmd, arg, 1);
|
|
#endif
|
|
}
|
|
|
|
|
|
/*
|
|
* The various file operations we support.
|
|
*/
|
|
|
|
static const struct file_operations rtc_fops = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = no_llseek,
|
|
.read = rtc_read,
|
|
#ifdef RTC_IRQ
|
|
.poll = rtc_poll,
|
|
#endif
|
|
.ioctl = rtc_ioctl,
|
|
.open = rtc_open,
|
|
.release = rtc_release,
|
|
.fasync = rtc_fasync,
|
|
};
|
|
|
|
static struct miscdevice rtc_dev = {
|
|
.minor = RTC_MINOR,
|
|
.name = "rtc",
|
|
.fops = &rtc_fops,
|
|
};
|
|
|
|
static const struct file_operations rtc_proc_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = rtc_proc_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = single_release,
|
|
};
|
|
|
|
#if defined(RTC_IRQ) && !defined(__sparc__)
|
|
static irqreturn_t (*rtc_int_handler_ptr)(int irq, void *dev_id, struct pt_regs *regs);
|
|
#endif
|
|
|
|
static int __init rtc_init(void)
|
|
{
|
|
struct proc_dir_entry *ent;
|
|
#if defined(__alpha__) || defined(__mips__)
|
|
unsigned int year, ctrl;
|
|
char *guess = NULL;
|
|
#endif
|
|
#ifdef __sparc__
|
|
struct linux_ebus *ebus;
|
|
struct linux_ebus_device *edev;
|
|
#ifdef __sparc_v9__
|
|
struct sparc_isa_bridge *isa_br;
|
|
struct sparc_isa_device *isa_dev;
|
|
#endif
|
|
#endif
|
|
#ifndef __sparc__
|
|
void *r;
|
|
#endif
|
|
|
|
#ifdef __sparc__
|
|
for_each_ebus(ebus) {
|
|
for_each_ebusdev(edev, ebus) {
|
|
if(strcmp(edev->prom_node->name, "rtc") == 0) {
|
|
rtc_port = edev->resource[0].start;
|
|
rtc_irq = edev->irqs[0];
|
|
goto found;
|
|
}
|
|
}
|
|
}
|
|
#ifdef __sparc_v9__
|
|
for_each_isa(isa_br) {
|
|
for_each_isadev(isa_dev, isa_br) {
|
|
if (strcmp(isa_dev->prom_node->name, "rtc") == 0) {
|
|
rtc_port = isa_dev->resource.start;
|
|
rtc_irq = isa_dev->irq;
|
|
goto found;
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
printk(KERN_ERR "rtc_init: no PC rtc found\n");
|
|
return -EIO;
|
|
|
|
found:
|
|
if (rtc_irq == PCI_IRQ_NONE) {
|
|
rtc_has_irq = 0;
|
|
goto no_irq;
|
|
}
|
|
|
|
/*
|
|
* XXX Interrupt pin #7 in Espresso is shared between RTC and
|
|
* PCI Slot 2 INTA# (and some INTx# in Slot 1).
|
|
*/
|
|
if (request_irq(rtc_irq, rtc_interrupt, IRQF_SHARED, "rtc", (void *)&rtc_port)) {
|
|
printk(KERN_ERR "rtc: cannot register IRQ %d\n", rtc_irq);
|
|
return -EIO;
|
|
}
|
|
no_irq:
|
|
#else
|
|
if (RTC_IOMAPPED)
|
|
r = request_region(RTC_PORT(0), RTC_IO_EXTENT, "rtc");
|
|
else
|
|
r = request_mem_region(RTC_PORT(0), RTC_IO_EXTENT, "rtc");
|
|
if (!r) {
|
|
printk(KERN_ERR "rtc: I/O resource %lx is not free.\n",
|
|
(long)(RTC_PORT(0)));
|
|
return -EIO;
|
|
}
|
|
|
|
#ifdef RTC_IRQ
|
|
if (is_hpet_enabled()) {
|
|
rtc_int_handler_ptr = hpet_rtc_interrupt;
|
|
} else {
|
|
rtc_int_handler_ptr = rtc_interrupt;
|
|
}
|
|
|
|
if(request_irq(RTC_IRQ, rtc_int_handler_ptr, IRQF_DISABLED, "rtc", NULL)) {
|
|
/* Yeah right, seeing as irq 8 doesn't even hit the bus. */
|
|
printk(KERN_ERR "rtc: IRQ %d is not free.\n", RTC_IRQ);
|
|
if (RTC_IOMAPPED)
|
|
release_region(RTC_PORT(0), RTC_IO_EXTENT);
|
|
else
|
|
release_mem_region(RTC_PORT(0), RTC_IO_EXTENT);
|
|
return -EIO;
|
|
}
|
|
hpet_rtc_timer_init();
|
|
|
|
#endif
|
|
|
|
#endif /* __sparc__ vs. others */
|
|
|
|
if (misc_register(&rtc_dev)) {
|
|
#ifdef RTC_IRQ
|
|
free_irq(RTC_IRQ, NULL);
|
|
#endif
|
|
release_region(RTC_PORT(0), RTC_IO_EXTENT);
|
|
return -ENODEV;
|
|
}
|
|
|
|
ent = create_proc_entry("driver/rtc", 0, NULL);
|
|
if (!ent) {
|
|
#ifdef RTC_IRQ
|
|
free_irq(RTC_IRQ, NULL);
|
|
#endif
|
|
release_region(RTC_PORT(0), RTC_IO_EXTENT);
|
|
misc_deregister(&rtc_dev);
|
|
return -ENOMEM;
|
|
}
|
|
ent->proc_fops = &rtc_proc_fops;
|
|
|
|
#if defined(__alpha__) || defined(__mips__)
|
|
rtc_freq = HZ;
|
|
|
|
/* Each operating system on an Alpha uses its own epoch.
|
|
Let's try to guess which one we are using now. */
|
|
|
|
if (rtc_is_updating() != 0)
|
|
msleep(20);
|
|
|
|
spin_lock_irq(&rtc_lock);
|
|
year = CMOS_READ(RTC_YEAR);
|
|
ctrl = CMOS_READ(RTC_CONTROL);
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
|
|
BCD_TO_BIN(year); /* This should never happen... */
|
|
|
|
if (year < 20) {
|
|
epoch = 2000;
|
|
guess = "SRM (post-2000)";
|
|
} else if (year >= 20 && year < 48) {
|
|
epoch = 1980;
|
|
guess = "ARC console";
|
|
} else if (year >= 48 && year < 72) {
|
|
epoch = 1952;
|
|
guess = "Digital UNIX";
|
|
#if defined(__mips__)
|
|
} else if (year >= 72 && year < 74) {
|
|
epoch = 2000;
|
|
guess = "Digital DECstation";
|
|
#else
|
|
} else if (year >= 70) {
|
|
epoch = 1900;
|
|
guess = "Standard PC (1900)";
|
|
#endif
|
|
}
|
|
if (guess)
|
|
printk(KERN_INFO "rtc: %s epoch (%lu) detected\n", guess, epoch);
|
|
#endif
|
|
#ifdef RTC_IRQ
|
|
if (rtc_has_irq == 0)
|
|
goto no_irq2;
|
|
|
|
init_timer(&rtc_irq_timer);
|
|
rtc_irq_timer.function = rtc_dropped_irq;
|
|
spin_lock_irq(&rtc_lock);
|
|
rtc_freq = 1024;
|
|
if (!hpet_set_periodic_freq(rtc_freq)) {
|
|
/* Initialize periodic freq. to CMOS reset default, which is 1024Hz */
|
|
CMOS_WRITE(((CMOS_READ(RTC_FREQ_SELECT) & 0xF0) | 0x06), RTC_FREQ_SELECT);
|
|
}
|
|
spin_unlock_irq(&rtc_lock);
|
|
no_irq2:
|
|
#endif
|
|
|
|
(void) init_sysctl();
|
|
|
|
printk(KERN_INFO "Real Time Clock Driver v" RTC_VERSION "\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __exit rtc_exit (void)
|
|
{
|
|
cleanup_sysctl();
|
|
remove_proc_entry ("driver/rtc", NULL);
|
|
misc_deregister(&rtc_dev);
|
|
|
|
#ifdef __sparc__
|
|
if (rtc_has_irq)
|
|
free_irq (rtc_irq, &rtc_port);
|
|
#else
|
|
if (RTC_IOMAPPED)
|
|
release_region(RTC_PORT(0), RTC_IO_EXTENT);
|
|
else
|
|
release_mem_region(RTC_PORT(0), RTC_IO_EXTENT);
|
|
#ifdef RTC_IRQ
|
|
if (rtc_has_irq)
|
|
free_irq (RTC_IRQ, NULL);
|
|
#endif
|
|
#endif /* __sparc__ */
|
|
}
|
|
|
|
module_init(rtc_init);
|
|
module_exit(rtc_exit);
|
|
|
|
#ifdef RTC_IRQ
|
|
/*
|
|
* At IRQ rates >= 4096Hz, an interrupt may get lost altogether.
|
|
* (usually during an IDE disk interrupt, with IRQ unmasking off)
|
|
* Since the interrupt handler doesn't get called, the IRQ status
|
|
* byte doesn't get read, and the RTC stops generating interrupts.
|
|
* A timer is set, and will call this function if/when that happens.
|
|
* To get it out of this stalled state, we just read the status.
|
|
* At least a jiffy of interrupts (rtc_freq/HZ) will have been lost.
|
|
* (You *really* shouldn't be trying to use a non-realtime system
|
|
* for something that requires a steady > 1KHz signal anyways.)
|
|
*/
|
|
|
|
static void rtc_dropped_irq(unsigned long data)
|
|
{
|
|
unsigned long freq;
|
|
|
|
spin_lock_irq (&rtc_lock);
|
|
|
|
if (hpet_rtc_dropped_irq()) {
|
|
spin_unlock_irq(&rtc_lock);
|
|
return;
|
|
}
|
|
|
|
/* Just in case someone disabled the timer from behind our back... */
|
|
if (rtc_status & RTC_TIMER_ON)
|
|
mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100);
|
|
|
|
rtc_irq_data += ((rtc_freq/HZ)<<8);
|
|
rtc_irq_data &= ~0xff;
|
|
rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0); /* restart */
|
|
|
|
freq = rtc_freq;
|
|
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n", freq);
|
|
|
|
/* Now we have new data */
|
|
wake_up_interruptible(&rtc_wait);
|
|
|
|
kill_fasync (&rtc_async_queue, SIGIO, POLL_IN);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Info exported via "/proc/driver/rtc".
|
|
*/
|
|
|
|
static int rtc_proc_show(struct seq_file *seq, void *v)
|
|
{
|
|
#define YN(bit) ((ctrl & bit) ? "yes" : "no")
|
|
#define NY(bit) ((ctrl & bit) ? "no" : "yes")
|
|
struct rtc_time tm;
|
|
unsigned char batt, ctrl;
|
|
unsigned long freq;
|
|
|
|
spin_lock_irq(&rtc_lock);
|
|
batt = CMOS_READ(RTC_VALID) & RTC_VRT;
|
|
ctrl = CMOS_READ(RTC_CONTROL);
|
|
freq = rtc_freq;
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
|
|
rtc_get_rtc_time(&tm);
|
|
|
|
/*
|
|
* There is no way to tell if the luser has the RTC set for local
|
|
* time or for Universal Standard Time (GMT). Probably local though.
|
|
*/
|
|
seq_printf(seq,
|
|
"rtc_time\t: %02d:%02d:%02d\n"
|
|
"rtc_date\t: %04d-%02d-%02d\n"
|
|
"rtc_epoch\t: %04lu\n",
|
|
tm.tm_hour, tm.tm_min, tm.tm_sec,
|
|
tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, epoch);
|
|
|
|
get_rtc_alm_time(&tm);
|
|
|
|
/*
|
|
* We implicitly assume 24hr mode here. Alarm values >= 0xc0 will
|
|
* match any value for that particular field. Values that are
|
|
* greater than a valid time, but less than 0xc0 shouldn't appear.
|
|
*/
|
|
seq_puts(seq, "alarm\t\t: ");
|
|
if (tm.tm_hour <= 24)
|
|
seq_printf(seq, "%02d:", tm.tm_hour);
|
|
else
|
|
seq_puts(seq, "**:");
|
|
|
|
if (tm.tm_min <= 59)
|
|
seq_printf(seq, "%02d:", tm.tm_min);
|
|
else
|
|
seq_puts(seq, "**:");
|
|
|
|
if (tm.tm_sec <= 59)
|
|
seq_printf(seq, "%02d\n", tm.tm_sec);
|
|
else
|
|
seq_puts(seq, "**\n");
|
|
|
|
seq_printf(seq,
|
|
"DST_enable\t: %s\n"
|
|
"BCD\t\t: %s\n"
|
|
"24hr\t\t: %s\n"
|
|
"square_wave\t: %s\n"
|
|
"alarm_IRQ\t: %s\n"
|
|
"update_IRQ\t: %s\n"
|
|
"periodic_IRQ\t: %s\n"
|
|
"periodic_freq\t: %ld\n"
|
|
"batt_status\t: %s\n",
|
|
YN(RTC_DST_EN),
|
|
NY(RTC_DM_BINARY),
|
|
YN(RTC_24H),
|
|
YN(RTC_SQWE),
|
|
YN(RTC_AIE),
|
|
YN(RTC_UIE),
|
|
YN(RTC_PIE),
|
|
freq,
|
|
batt ? "okay" : "dead");
|
|
|
|
return 0;
|
|
#undef YN
|
|
#undef NY
|
|
}
|
|
|
|
static int rtc_proc_open(struct inode *inode, struct file *file)
|
|
{
|
|
return single_open(file, rtc_proc_show, NULL);
|
|
}
|
|
|
|
void rtc_get_rtc_time(struct rtc_time *rtc_tm)
|
|
{
|
|
unsigned long uip_watchdog = jiffies, flags;
|
|
unsigned char ctrl;
|
|
#ifdef CONFIG_MACH_DECSTATION
|
|
unsigned int real_year;
|
|
#endif
|
|
|
|
/*
|
|
* read RTC once any update in progress is done. The update
|
|
* can take just over 2ms. We wait 20ms. There is no need to
|
|
* to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP.
|
|
* If you need to know *exactly* when a second has started, enable
|
|
* periodic update complete interrupts, (via ioctl) and then
|
|
* immediately read /dev/rtc which will block until you get the IRQ.
|
|
* Once the read clears, read the RTC time (again via ioctl). Easy.
|
|
*/
|
|
|
|
while (rtc_is_updating() != 0 && jiffies - uip_watchdog < 2*HZ/100) {
|
|
barrier();
|
|
cpu_relax();
|
|
}
|
|
|
|
/*
|
|
* Only the values that we read from the RTC are set. We leave
|
|
* tm_wday, tm_yday and tm_isdst untouched. Note that while the
|
|
* RTC has RTC_DAY_OF_WEEK, we should usually ignore it, as it is
|
|
* only updated by the RTC when initially set to a non-zero value.
|
|
*/
|
|
spin_lock_irqsave(&rtc_lock, flags);
|
|
rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS);
|
|
rtc_tm->tm_min = CMOS_READ(RTC_MINUTES);
|
|
rtc_tm->tm_hour = CMOS_READ(RTC_HOURS);
|
|
rtc_tm->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);
|
|
rtc_tm->tm_mon = CMOS_READ(RTC_MONTH);
|
|
rtc_tm->tm_year = CMOS_READ(RTC_YEAR);
|
|
/* Only set from 2.6.16 onwards */
|
|
rtc_tm->tm_wday = CMOS_READ(RTC_DAY_OF_WEEK);
|
|
|
|
#ifdef CONFIG_MACH_DECSTATION
|
|
real_year = CMOS_READ(RTC_DEC_YEAR);
|
|
#endif
|
|
ctrl = CMOS_READ(RTC_CONTROL);
|
|
spin_unlock_irqrestore(&rtc_lock, flags);
|
|
|
|
if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
|
|
{
|
|
BCD_TO_BIN(rtc_tm->tm_sec);
|
|
BCD_TO_BIN(rtc_tm->tm_min);
|
|
BCD_TO_BIN(rtc_tm->tm_hour);
|
|
BCD_TO_BIN(rtc_tm->tm_mday);
|
|
BCD_TO_BIN(rtc_tm->tm_mon);
|
|
BCD_TO_BIN(rtc_tm->tm_year);
|
|
BCD_TO_BIN(rtc_tm->tm_wday);
|
|
}
|
|
|
|
#ifdef CONFIG_MACH_DECSTATION
|
|
rtc_tm->tm_year += real_year - 72;
|
|
#endif
|
|
|
|
/*
|
|
* Account for differences between how the RTC uses the values
|
|
* and how they are defined in a struct rtc_time;
|
|
*/
|
|
if ((rtc_tm->tm_year += (epoch - 1900)) <= 69)
|
|
rtc_tm->tm_year += 100;
|
|
|
|
rtc_tm->tm_mon--;
|
|
}
|
|
|
|
static void get_rtc_alm_time(struct rtc_time *alm_tm)
|
|
{
|
|
unsigned char ctrl;
|
|
|
|
/*
|
|
* Only the values that we read from the RTC are set. That
|
|
* means only tm_hour, tm_min, and tm_sec.
|
|
*/
|
|
spin_lock_irq(&rtc_lock);
|
|
alm_tm->tm_sec = CMOS_READ(RTC_SECONDS_ALARM);
|
|
alm_tm->tm_min = CMOS_READ(RTC_MINUTES_ALARM);
|
|
alm_tm->tm_hour = CMOS_READ(RTC_HOURS_ALARM);
|
|
ctrl = CMOS_READ(RTC_CONTROL);
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
|
|
{
|
|
BCD_TO_BIN(alm_tm->tm_sec);
|
|
BCD_TO_BIN(alm_tm->tm_min);
|
|
BCD_TO_BIN(alm_tm->tm_hour);
|
|
}
|
|
}
|
|
|
|
#ifdef RTC_IRQ
|
|
/*
|
|
* Used to disable/enable interrupts for any one of UIE, AIE, PIE.
|
|
* Rumour has it that if you frob the interrupt enable/disable
|
|
* bits in RTC_CONTROL, you should read RTC_INTR_FLAGS, to
|
|
* ensure you actually start getting interrupts. Probably for
|
|
* compatibility with older/broken chipset RTC implementations.
|
|
* We also clear out any old irq data after an ioctl() that
|
|
* meddles with the interrupt enable/disable bits.
|
|
*/
|
|
|
|
static void mask_rtc_irq_bit_locked(unsigned char bit)
|
|
{
|
|
unsigned char val;
|
|
|
|
if (hpet_mask_rtc_irq_bit(bit))
|
|
return;
|
|
val = CMOS_READ(RTC_CONTROL);
|
|
val &= ~bit;
|
|
CMOS_WRITE(val, RTC_CONTROL);
|
|
CMOS_READ(RTC_INTR_FLAGS);
|
|
|
|
rtc_irq_data = 0;
|
|
}
|
|
|
|
static void set_rtc_irq_bit_locked(unsigned char bit)
|
|
{
|
|
unsigned char val;
|
|
|
|
if (hpet_set_rtc_irq_bit(bit))
|
|
return;
|
|
val = CMOS_READ(RTC_CONTROL);
|
|
val |= bit;
|
|
CMOS_WRITE(val, RTC_CONTROL);
|
|
CMOS_READ(RTC_INTR_FLAGS);
|
|
|
|
rtc_irq_data = 0;
|
|
}
|
|
#endif
|
|
|
|
MODULE_AUTHOR("Paul Gortmaker");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_MISCDEV(RTC_MINOR);
|