diff options
Diffstat (limited to 'drivers/char/sh03rtc.c')
| -rw-r--r-- | drivers/char/sh03rtc.c | 1185 |
1 files changed, 1185 insertions, 0 deletions
diff --git a/drivers/char/sh03rtc.c b/drivers/char/sh03rtc.c new file mode 100644 index 00000000000000..09c5643b1f78d6 --- /dev/null +++ b/drivers/char/sh03rtc.c @@ -0,0 +1,1185 @@ +/* + * Real Time Clock interface for Linux + * + * Copyright (C) 2004 Interface Corporation Saito.K + * + * Based on skelrton from the drivers/char/rtc.c + * + * This driver allows use of the real time clock (built into + * nearly all computers) from user space. It exports the /dev/rtc + * interface supporting various ioctl() and also the + * /proc/driver/rtc pseudo-file for status information. + * + * The ioctls can be used to set the interrupt behaviour and + * generation rate from the RTC via IRQ 8. Then the /dev/rtc + * interface can be used to make use of these timer interrupts, + * be they interval or alarm based. + * + * The /dev/rtc interface will block on reads until an interrupt + * has been received. If a RTC interrupt has already happened, + * it will output an unsigned long and then block. The output value + * contains the interrupt status in the low byte and the number of + * interrupts since the last read in the remaining high bytes. The + * /dev/rtc interface can also be used with the select(2) call. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * Based on other minimal char device drivers, like Alan's + * watchdog, Ted's random, etc. etc. + * + * 1.07 Paul Gortmaker. + * 1.08 Miquel van Smoorenburg: disallow certain things on the + * DEC Alpha as the CMOS clock is also used for other things. + * 1.09 Nikita Schmidt: epoch support and some Alpha cleanup. + * 1.09a Pete Zaitcev: Sun SPARC + * 1.09b Jeff Garzik: Modularize, init cleanup + * 1.09c Jeff Garzik: SMP cleanup + * 1.10 Paul Barton-Davis: add support for async I/O + * 1.10a Andrea Arcangeli: Alpha updates + * 1.10b Andrew Morton: SMP lock fix + * 1.10c Cesar Barros: SMP locking fixes and cleanup + * 1.10d Paul Gortmaker: delete paranoia check in rtc_exit + * 1.10e Maciej W. Rozycki: Handle DECstation's year weirdness. + * 1.11 Takashi Iwai: Kernel access functions + * rtc_register/rtc_unregister/rtc_control + * 1.11a Daniele Bellucci: Audit create_proc_read_entry in rtc_init + * 1.12 Venkatesh Pallipadi: Hooks for emulating rtc on HPET base-timer + * CONFIG_HPET_EMULATE_RTC + * + */ + +#define SH03_RTC_VERSION "0.09" + +#define RTC_IO_EXTENT 0x8 + +/* + * Note that *all* calls to CMOS_READ and CMOS_WRITE are done with + * interrupts disabled. Due to the index-port/data-port (0x70/0x71) + * design of the RTC, we don't want two different things trying to + * get to it at once. (e.g. the periodic 11 min sync from time.c vs. + * this driver.) + */ + +#include <linux/config.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/miscdevice.h> +#include <linux/ioport.h> +#include <linux/fcntl.h> + +// @@@@@ 16.09.29 #include <linux/mc146818rtc.h> +#include <linux/rtc.h> + +#include <linux/init.h> +#include <linux/poll.h> +#include <linux/proc_fs.h> +#include <linux/spinlock.h> +#include <linux/sysctl.h> +#include <linux/wait.h> +#include <linux/bcd.h> + +#include <asm/current.h> +#include <asm/uaccess.h> +#include <asm/system.h> +#include <asm/io.h> + +extern spinlock_t rtc_lock; + +/* +TODO: Timer +*/ +#define SH03_RTC_IRQ 11 + +#define RTC_BASE 0xb0000000 +#define RTC_SEC1 (RTC_BASE + 0) +#define RTC_SEC10 (RTC_BASE + 1) +#define RTC_MIN1 (RTC_BASE + 2) +#define RTC_MIN10 (RTC_BASE + 3) +#define RTC_HOU1 (RTC_BASE + 4) +#define RTC_HOU10 (RTC_BASE + 5) +#define RTC_WEE1 (RTC_BASE + 6) +#define RTC_DAY1 (RTC_BASE + 7) +#define RTC_DAY10 (RTC_BASE + 8) +#define RTC_MON1 (RTC_BASE + 9) +#define RTC_MON10 (RTC_BASE + 10) +#define RTC_YEA1 (RTC_BASE + 11) +#define RTC_YEA10 (RTC_BASE + 12) +#define RTC_YEA100 (RTC_BASE + 13) +#define RTC_YEA1000 (RTC_BASE + 14) +#define RTC_CTL (RTC_BASE + 15) +#define RTC_BUSY 1 +#define RTC_STOP 2 +#define RTC_BANK0 (0 << 2) +#define RTC_BANK1 (1 << 2) +#define RTC_BANK2 (2 << 2) + +#define RTC_ATCTL (RTC_BASE + 14) +#define RTC_AIE 1 +#define RTC_AF 2 + +#define RTC_TE_CLOCK (RTC_BASE + 8) +#define RTC_TMCTL (RTC_BASE + 14) +#define RTC_TIE 1 +#define RTC_TF 2 + +#define SH03_RTC_PORT(n) ((RTC_BASE) + n) +#define SH03_RTC_IO_EXTENT 0x10 + +#ifndef BIN_TO_BCD +#define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10) +#endif + +#define SELECT_BANK(n) ctrl_outb((n), RTC_CTL) + +#define READ_SECONDS ((ctrl_inb(RTC_SEC1) & 15) + (ctrl_inb(RTC_SEC10) & 7) * 10) +#define READ_MINUTES ((ctrl_inb(RTC_MIN1) & 15) + (ctrl_inb(RTC_MIN10) & 7) * 10) +#define READ_HOURS ((ctrl_inb(RTC_HOU1) & 15) + (ctrl_inb(RTC_HOU10) & 3) * 10) +#define READ_WEEK (ctrl_inb(RTC_WEE1) & 7) +#define READ_DAY ((ctrl_inb(RTC_DAY1) & 15) + (ctrl_inb(RTC_DAY10) & 3) * 10) +#define READ_MONTH ((ctrl_inb(RTC_MON1) & 15) + (ctrl_inb(RTC_MON10) & 1) * 10) +#define READ_YEAR ((ctrl_inb(RTC_YEA1) & 15) + (ctrl_inb(RTC_YEA10) & 15) * 10 \ + + (ctrl_inb(RTC_YEA100) & 15) * 100 + (ctrl_inb(RTC_YEA1000) & 3) * 1000) + +#define WRITE_SECONDS(d) ctrl_outb((d) & 15, RTC_SEC1); ctrl_outb((d) >> 4, RTC_SEC10) +#define WRITE_MINUTES(d) ctrl_outb((d) & 15, RTC_MIN1); ctrl_outb((d) >> 4, RTC_MIN10) +#define WRITE_HOURS(d) ctrl_outb((d) & 15, RTC_HOU1); ctrl_outb((d) >> 4, RTC_HOU10) +#define WRITE_WEEK(d) ctrl_outb((d) & 15, RTC_WEE1) +#define WRITE_DAY(d) ctrl_outb((d) & 15, RTC_DAY1); ctrl_outb((d) >> 4, RTC_DAY10) +#define WRITE_MONTH(d) ctrl_outb((d) & 15, RTC_MON1); ctrl_outb((d) >> 4, RTC_MON10) +#define WRITE_YEAR_LOW(d) ctrl_outb((d) & 15, RTC_YEA1); ctrl_outb((d) >> 4, RTC_YEA10) +#define WRITE_YEAR_HIGH(d) ctrl_outb((d) & 15, RTC_YEA100); ctrl_outb((d) >> 4, RTC_YEA1000) + +#define READ_ATCTL (ctrl_inb(RTC_ATCTL)) +#define WRITE_ATCTL(d) ctrl_outb((d), RTC_ATCTL) + +#define READ_TMCTL (ctrl_inb(RTC_TMCTL)) +#define WRITE_TMCTL(d) ctrl_outb((d), RTC_TMCTL) + +#define READ_CLOCK (ctrl_inb(RTC_TE_CLOCK)) +#define WRITE_CLOCK(d) ctrl_outb((d) & 15, RTC_TE_CLOCK) + + + +#ifdef SH03_RTC_IRQ +static int sh03_rtc_has_irq = SH03_RTC_IRQ; +#endif + +/* + * We sponge a minor off of the misc major. No need slurping + * up another valuable major dev number for this. If you add + * an ioctl, make sure you don't conflict with SPARC's RTC + * ioctls. + */ + +static struct fasync_struct *sh03_rtc_async_queue; + +static DECLARE_WAIT_QUEUE_HEAD(sh03_rtc_wait); + +#ifdef SH03_RTC_IRQ +static struct timer_list sh03_rtc_irq_timer; +#endif + +static ssize_t sh03_rtc_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos); + +static int sh03_rtc_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg); + +#ifdef SH03_RTC_IRQ +static unsigned int sh03_rtc_poll(struct file *file, poll_table *wait); +#endif + +void sh03_rtc_get_rtc_time(struct rtc_time *rtc_tm); +static void sh03_get_rtc_alm_time (struct rtc_time *alm_tm); +#ifdef SH03_RTC_IRQ +static void sh03_rtc_dropped_irq(unsigned long data); + +static void sh03_set_rtc_irq_bit(unsigned int bit); +static void sh03_mask_rtc_irq_bit(unsigned int bit); +#endif + +static int sh03_rtc_read_proc(char *page, char **start, off_t off, + int count, int *eof, void *data); + +/* + * Bits in rtc_status. (6 bits of room for future expansion) + */ + +#define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */ +#define RTC_TIMER_ON 0x02 /* missed irq timer active */ + +/* + * rtc_status is never changed by rtc_interrupt, and ioctl/open/close is + * protected by the big kernel lock. However, ioctl can still disable the timer + * in rtc_status and then with del_timer after the interrupt has read + * rtc_status but before mod_timer is called, which would then reenable the + * timer (but you would need to have an awful timing before you'd trip on it) + */ +static unsigned long rtc_status = 0; /* bitmapped status byte. */ +static unsigned long rtc_freq = 0; /* Current periodic IRQ rate */ +static unsigned long rtc_irq_data = 0; /* our output to the world */ +static unsigned long rtc_max_user_freq = 64; /* > this, need CAP_SYS_RESOURCE */ + +#ifdef SH03_RTC_IRQ +/* + * rtc_task_lock nests inside rtc_lock. + */ +static spinlock_t rtc_task_lock = SPIN_LOCK_UNLOCKED; +static rtc_task_t *rtc_callback = NULL; +#endif + +/* + * If this driver ever becomes modularised, it will be really nice + * to make the epoch retain its value across module reload... + */ + +static unsigned long epoch = 1900; /* year corresponding to 0x00 */ + +static const unsigned char days_in_mo[] = +{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; + +#if 0 /* @@@@@ 16.09.29 TODO */ +/* + * Returns true if a clock update is in progress + */ +static inline unsigned char rtc_is_updating(void) +{ + unsigned char uip; + + spin_lock_irq(&rtc_lock); + uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP); + spin_unlock_irq(&rtc_lock); + return uip; +} +#endif + +#ifdef SH03_RTC_IRQ +/* + * A very tiny interrupt handler. It runs with SA_INTERRUPT set, + * but there is possibility of conflicting with the set_rtc_mmss() + * call (the rtc irq and the timer irq can easily run at the same + * time in two different CPUs). So we need to serialize + * accesses to the chip with the rtc_lock spinlock that each + * architecture should implement in the timer code. + * (See ./arch/XXXX/kernel/time.c for the set_rtc_mmss() function.) + */ + +irqreturn_t sh03_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + /* + * Can be an alarm interrupt, update complete interrupt, + * or a periodic interrupt. We store the status in the + * low byte and the number of interrupts received since + * the last read in the remainder of rtc_irq_data. + */ + + spin_lock (&rtc_lock); + rtc_irq_data += 0x100; + rtc_irq_data &= ~0xff; + SELECT_BANK(RTC_BANK1); + rtc_irq_data |= (READ_ATCTL & RTC_AF) >> 1; + WRITE_ATCTL(READ_ATCTL & ~ RTC_AF); + SELECT_BANK(RTC_BANK2); + rtc_irq_data |= (READ_TMCTL & RTC_TF); + WRITE_TMCTL(READ_TMCTL & ~ RTC_TF); + SELECT_BANK(RTC_BANK0); + + if (rtc_status & RTC_TIMER_ON) + mod_timer(&sh03_rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100); + + spin_unlock (&rtc_lock); + + /* Now do the rest of the actions */ + spin_lock(&rtc_task_lock); + if (rtc_callback) + rtc_callback->func(rtc_callback->private_data); + spin_unlock(&rtc_task_lock); + wake_up_interruptible(&sh03_rtc_wait); + + kill_fasync (&sh03_rtc_async_queue, SIGIO, POLL_IN); + + return IRQ_HANDLED; +} +#endif + +/* + * sysctl-tuning infrastructure. + */ +static ctl_table rtc_table[] = { + { + .ctl_name = 1, + .procname = "max-user-freq", + .data = &rtc_max_user_freq, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { .ctl_name = 0 } +}; + +static ctl_table rtc_root[] = { + { + .ctl_name = 1, + .procname = "rtc", + .maxlen = 0, + .mode = 0555, + .child = rtc_table, + }, + { .ctl_name = 0 } +}; + +static ctl_table dev_root[] = { + { + .ctl_name = CTL_DEV, + .procname = "dev", + .maxlen = 0, + .mode = 0555, + .child = rtc_root, + }, + { .ctl_name = 0 } +}; + +static struct ctl_table_header *sysctl_header; + +static int __init init_sysctl(void) +{ + sysctl_header = register_sysctl_table(dev_root, 0); + return 0; +} + +static void __exit cleanup_sysctl(void) +{ + unregister_sysctl_table(sysctl_header); +} + +/* + * Now all the various file operations that we export. + */ + +static ssize_t sh03_rtc_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ +#ifndef SH03_RTC_IRQ + return -EIO; +#else + DECLARE_WAITQUEUE(wait, current); + unsigned long data; + ssize_t retval; + + if (sh03_rtc_has_irq == 0) + return -EIO; + + if (count < sizeof(unsigned)) + return -EINVAL; + + add_wait_queue(&sh03_rtc_wait, &wait); + + do { + /* First make it right. Then make it fast. Putting this whole + * block within the parentheses of a while would be too + * confusing. And no, xchg() is not the answer. */ + + __set_current_state(TASK_INTERRUPTIBLE); + + spin_lock_irq (&rtc_lock); + data = rtc_irq_data; + rtc_irq_data = 0; + spin_unlock_irq (&rtc_lock); + + if (data != 0) + break; + + if (file->f_flags & O_NONBLOCK) { + retval = -EAGAIN; + goto out; + } + if (signal_pending(current)) { + retval = -ERESTARTSYS; + goto out; + } + schedule(); + } while (1); + + if (count < sizeof(unsigned long)) + retval = put_user(data, (unsigned int __user *)buf) ?: sizeof(int); + else + retval = put_user(data, (unsigned long __user *)buf) ?: sizeof(long); + out: + current->state = TASK_RUNNING; + remove_wait_queue(&sh03_rtc_wait, &wait); + + return retval; +#endif +} + +static int sh03_rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel) +{ + struct rtc_time wtime; + +#ifdef SH03_RTC_IRQ + if (sh03_rtc_has_irq == 0) { + switch (cmd) { + case RTC_AIE_OFF: + case RTC_AIE_ON: + case RTC_PIE_OFF: + case RTC_PIE_ON: + case RTC_UIE_OFF: + case RTC_UIE_ON: + case RTC_IRQP_READ: + case RTC_IRQP_SET: + return -EINVAL; + }; + } +#endif + + switch (cmd) { +#ifdef SH03_RTC_IRQ + case RTC_AIE_OFF: /* Mask alarm int. enab. bit */ + { + sh03_mask_rtc_irq_bit(RTC_AIE); + return 0; + } + case RTC_AIE_ON: /* Allow alarm interrupts. */ + { + sh03_set_rtc_irq_bit(RTC_AIE); + return 0; + } + case RTC_PIE_OFF: /* Mask periodic int. enab. bit */ + { + sh03_mask_rtc_irq_bit(RTC_PIE_OFF); + if (rtc_status & RTC_TIMER_ON) { + spin_lock_irq (&rtc_lock); + rtc_status &= ~RTC_TIMER_ON; + del_timer(&sh03_rtc_irq_timer); + spin_unlock_irq (&rtc_lock); + } + return 0; + } + case RTC_PIE_ON: /* Allow periodic ints */ + { + + /* + * We don't really want Joe User enabling more + * than 64Hz of interrupts on a multi-user machine. + */ + if (!kernel && (rtc_freq > rtc_max_user_freq) && + (!capable(CAP_SYS_RESOURCE))) + return -EACCES; + + if (!(rtc_status & RTC_TIMER_ON)) { + spin_lock_irq (&rtc_lock); + sh03_rtc_irq_timer.expires = jiffies + HZ/rtc_freq + 2*HZ/100; + add_timer(&sh03_rtc_irq_timer); + rtc_status |= RTC_TIMER_ON; + spin_unlock_irq (&rtc_lock); + } + sh03_set_rtc_irq_bit(RTC_PIE_ON); + return 0; + } +#if 1 /* @@@@@ 16.09.29 TODO */ + case RTC_UIE_OFF: /* Mask ints from RTC updates. */ + case RTC_UIE_ON: /* Allow ints for RTC updates. */ + return -EINVAL; +#else + case RTC_UIE_OFF: /* Mask ints from RTC updates. */ + { + sh03_mask_rtc_irq_bit(RTC_UIE); + return 0; + } + case RTC_UIE_ON: /* Allow ints for RTC updates. */ + { + sh03_set_rtc_irq_bit(RTC_UIE); + return 0; + } +#endif +#endif + case RTC_ALM_READ: /* Read the present alarm time */ + { + /* + * This returns a struct rtc_time. Reading >= 0xc0 + * means "don't care" or "match all". Only the tm_hour, + * tm_min, and tm_sec values are filled in. + */ + memset(&wtime, 0, sizeof(struct rtc_time)); + sh03_get_rtc_alm_time(&wtime); + break; + } + case RTC_ALM_SET: /* Store a time into the alarm */ + { + /* + * This expects a struct rtc_time. Writing 0xff means + * "don't care" or "match all". Only the tm_hour, + * tm_min and tm_sec are used. + */ + unsigned char day, week, 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; + + day = alm_tm.tm_mday; + week = alm_tm.tm_wday; + hrs = alm_tm.tm_hour; + min = alm_tm.tm_min; + sec = alm_tm.tm_sec; + if (day >= 31) + day = 99; + + if (week >= 7) + week = 9; + + if (hrs >= 24) + hrs = 99; + + if (min >= 60) + min = 99; + + if (sec >= 60) + sec = 99; + + spin_lock_irq(&rtc_lock); + BIN_TO_BCD(sec); + BIN_TO_BCD(min); + BIN_TO_BCD(hrs); + BIN_TO_BCD(day); + SELECT_BANK(RTC_BANK1); + WRITE_DAY(day); + WRITE_WEEK(week); + WRITE_HOURS(hrs); + WRITE_MINUTES(min); + WRITE_SECONDS(sec); + SELECT_BANK(RTC_BANK0); + spin_unlock_irq(&rtc_lock); + + return 0; + } + case RTC_RD_TIME: /* Read the time/date from RTC */ + { + memset(&wtime, 0, sizeof(struct rtc_time)); + sh03_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 int yrs, yrs_low, yrs_high; + + 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); + + /* 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; + + yrs += epoch; + BIN_TO_BCD(sec); + BIN_TO_BCD(min); + BIN_TO_BCD(hrs); + BIN_TO_BCD(day); + BIN_TO_BCD(mon); + yrs_low = yrs % 100; + yrs_high = yrs / 100; + BIN_TO_BCD(yrs_low); + BIN_TO_BCD(yrs_high); + + WRITE_YEAR_HIGH(yrs_high); + WRITE_YEAR_LOW(yrs_low); + WRITE_MONTH(mon); + WRITE_DAY(day); + WRITE_HOURS(hrs); + WRITE_MINUTES(min); + WRITE_SECONDS(sec); + + spin_unlock_irq(&rtc_lock); + return 0; + } +#ifdef SH03_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; + + /* + * 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; + + switch (arg) { + case 1: tmp = 2; break; + case 64: tmp = 1; break; + case 4096: tmp = 0; break; + default: return -EINVAL; + } + + spin_lock_irq(&rtc_lock); + rtc_freq = arg; + SELECT_BANK(RTC_BANK2); + WRITE_CLOCK((READ_CLOCK & ~3) | tmp); + SELECT_BANK(RTC_BANK0); + spin_unlock_irq(&rtc_lock); + 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 sh03_rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, + unsigned long arg) +{ + return sh03_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 sh03_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 sh03_rtc_fasync (int fd, struct file *filp, int on) + +{ + return fasync_helper (fd, filp, on, &sh03_rtc_async_queue); +} + +static int sh03_rtc_release(struct inode *inode, struct file *file) +{ +#ifdef SH03_RTC_IRQ + if (sh03_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); + SELECT_BANK(RTC_BANK1); + ctrl_outb(0, RTC_ATCTL); + SELECT_BANK(RTC_BANK2); + ctrl_outb(0, RTC_TMCTL); + SELECT_BANK(RTC_BANK0); + + if (rtc_status & RTC_TIMER_ON) { + rtc_status &= ~RTC_TIMER_ON; + del_timer(&sh03_rtc_irq_timer); + } + spin_unlock_irq(&rtc_lock); + + if (file->f_flags & FASYNC) { + sh03_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 SH03_RTC_IRQ +/* Called without the kernel lock - fine */ +static unsigned int sh03_rtc_poll(struct file *file, poll_table *wait) +{ + unsigned long l; + + if (sh03_rtc_has_irq == 0) + return 0; + + poll_wait(file, &sh03_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 + +int rtc_control(rtc_task_t *task, unsigned int cmd, unsigned long arg) +{ +#ifndef SH03_RTC_IRQ + return -EIO; +#else + spin_lock_irq(&rtc_task_lock); + if (rtc_callback != task) { + spin_unlock_irq(&rtc_task_lock); + return -ENXIO; + } + spin_unlock_irq(&rtc_task_lock); + return sh03_rtc_do_ioctl(cmd, arg, 1); +#endif +} + + +/* + * The various file operations we support. + */ + +static struct file_operations sh03_rtc_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .read = sh03_rtc_read, +#ifdef SH03_RTC_IRQ + .poll = sh03_rtc_poll, +#endif + .ioctl = sh03_rtc_ioctl, + .open = sh03_rtc_open, + .release = sh03_rtc_release, + .fasync = sh03_rtc_fasync, +}; + +static struct miscdevice sh03_rtc_dev= +{ + RTC_MINOR, + "sh03-rtc", + &sh03_rtc_fops +}; + +#ifdef SH03_RTC_IRQ +static irqreturn_t (*rtc_int_handler_ptr)(int irq, void *dev_id, struct pt_regs *regs); +#endif + +static int __init sh03_rtc_init(void) +{ + if (!request_region(SH03_RTC_PORT(0), SH03_RTC_IO_EXTENT, "sh03-rtc")) { + printk(KERN_ERR "sh03-rtc: I/O port %d is not free.\n", SH03_RTC_PORT (0)); + return -EIO; + } + +#ifdef SH03_RTC_IRQ + rtc_int_handler_ptr = sh03_rtc_interrupt; + if(request_irq(SH03_RTC_IRQ, rtc_int_handler_ptr, SA_INTERRUPT, "sh03-rtc", NULL)) { + /* Yeah right, seeing as irq 8 doesn't even hit the bus. */ + printk(KERN_ERR "sh03-rtc: IRQ %d is not free.\n", RTC_IRQ); + release_region(SH03_RTC_PORT(0), SH03_RTC_IO_EXTENT); + return -EIO; + } +#endif + + if (misc_register(&sh03_rtc_dev)) { +#ifdef SH03_RTC_IRQ + free_irq(SH03_RTC_IRQ, NULL); +#endif + release_region(SH03_RTC_PORT(0), SH03_RTC_IO_EXTENT); + return -ENODEV; + } + if (!create_proc_read_entry ("driver/sh03-rtc", 0, NULL, sh03_rtc_read_proc, NULL)) { +#ifdef SH03_RTC_IRQ + free_irq(SH03_RTC_IRQ, NULL); +#endif + release_region(SH03_RTC_PORT(0), SH03_RTC_IO_EXTENT); + misc_deregister(&sh03_rtc_dev); + return -ENOMEM; + } + +#ifdef SH03_RTC_IRQ + if (sh03_rtc_has_irq == 0) + goto no_irq2; + + init_timer(&sh03_rtc_irq_timer); + sh03_rtc_irq_timer.function = sh03_rtc_dropped_irq; + spin_lock_irq(&rtc_lock); + SELECT_BANK(RTC_BANK2); + WRITE_CLOCK(2); + SELECT_BANK(RTC_BANK0); + rtc_freq = 1; + spin_unlock_irq(&rtc_lock); +no_irq2: +#endif + + (void) init_sysctl(); + + printk(KERN_INFO "CTP/PCI-SH03 Real Time Clock Driver v" SH03_RTC_VERSION "\n"); + + return 0; +} + +static void __exit sh03_rtc_exit (void) +{ + cleanup_sysctl(); + remove_proc_entry ("driver/sh03-rtc", NULL); + misc_deregister(&sh03_rtc_dev); + release_region (SH03_RTC_PORT (0), SH03_RTC_IO_EXTENT); +#ifdef SH03_RTC_IRQ + if (sh03_rtc_has_irq) + free_irq (SH03_RTC_IRQ, NULL); +#endif +} + +module_init(sh03_rtc_init); +module_exit(sh03_rtc_exit); + +#ifdef SH03_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 sh03_rtc_dropped_irq(unsigned long data) +{ + unsigned long freq; + + spin_lock_irq (&rtc_lock); + + /* Just in case someone disabled the timer from behind our back... */ + if (rtc_status & RTC_TIMER_ON) + mod_timer(&sh03_rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100); + + rtc_irq_data += ((rtc_freq/HZ)<<8); + rtc_irq_data &= ~0xff; + SELECT_BANK(RTC_BANK1); + rtc_irq_data |= (READ_ATCTL & RTC_AF) >> 1; + SELECT_BANK(RTC_BANK2); + rtc_irq_data |= (READ_TMCTL & RTC_TF); + SELECT_BANK(RTC_BANK0); + + freq = rtc_freq; + + spin_unlock_irq(&rtc_lock); + + printk(KERN_WARNING "sh03-rtc: lost some interrupts at %ldHz.\n", freq); + + /* Now we have new data */ + wake_up_interruptible(&sh03_rtc_wait); + + kill_fasync (&sh03_rtc_async_queue, SIGIO, POLL_IN); +} +#endif + +/* + * Info exported via "/proc/driver/sh03-rtc". + */ + +static int sh03_rtc_proc_output (char *buf) +{ +#define YN(bit) ((bit) ? "yes" : "no") +#define NY(bit) ((bit) ? "no" : "yes") + char *p; + struct rtc_time tm; + unsigned char aie, tie, af, tf; + unsigned long freq; + int sec_ae, min_ae, hour_ae, week_ae, day_ae; + + spin_lock_irq(&rtc_lock); + SELECT_BANK(RTC_BANK1); + aie = READ_ATCTL & RTC_AIE; + af = READ_ATCTL & 2; + sec_ae = ctrl_inb(RTC_SEC10) & 8; + min_ae = ctrl_inb(RTC_MIN10) & 8; + hour_ae = ctrl_inb(RTC_HOU10) & 8; + week_ae = ctrl_inb(RTC_WEE1 ) & 8; + day_ae = ctrl_inb(RTC_DAY10) & 8; + SELECT_BANK(RTC_BANK2); + tie = READ_TMCTL & RTC_TIE; + tf = READ_TMCTL & 2; + SELECT_BANK(RTC_BANK0); + freq = rtc_freq; + spin_unlock_irq(&rtc_lock); + + p = buf; + + sh03_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. + */ + p += sprintf(p, + "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); + + sh03_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. + */ + p += sprintf(p, "alarm\t\t: "); + if (!day_ae) + p += sprintf(p, "%02d ", tm.tm_mday); + else + p += sprintf(p, "** "); + if (!week_ae) + p += sprintf(p, "%01d ", tm.tm_wday); + else + p += sprintf(p, "* "); + if (!hour_ae) + p += sprintf(p, "%02d:", tm.tm_hour); + else + p += sprintf(p, "**:"); + + if (!min_ae) + p += sprintf(p, "%02d:", tm.tm_min); + else + p += sprintf(p, "**:"); + + if (!sec_ae) + p += sprintf(p, "%02d\n", tm.tm_sec); + else + p += sprintf(p, "**\n"); + + p += sprintf(p, + "alarm_IRQ\t: %s-%s\n" + "periodic_IRQ\t: %s-%s\n" + "periodic_freq\t: %ld\n" + "FOS\t\t: %s\n" + "Control Reg\t: %x\n", + YN(aie),YN(af), + YN(tie),YN(tf), + freq, + ctrl_inb(RTC_SEC10) & 8 ? "on" : "off", + ctrl_inb(RTC_CTL) & 15); + + return p - buf; +#undef YN +#undef NY +} + +static int sh03_rtc_read_proc(char *page, char **start, off_t off, + int count, int *eof, void *data) +{ + int len = sh03_rtc_proc_output (page); + if (len <= off+count) *eof = 1; + *start = page + off; + len -= off; + if (len>count) len = count; + if (len<0) len = 0; + return len; +} + +void sh03_rtc_get_rtc_time(struct rtc_time *rtc_tm) +{ +// @@@@@ 16.09.29 TODO unsigned long uip_watchdog = jiffies; + + /* + * read RTC once any update in progress is done. The update + * can take just over 2ms. We wait 10 to 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. + */ + +#if 0 /* @@@@@ 16.09.29 TODO */ + if (rtc_is_updating() != 0) + while (jiffies - uip_watchdog < 2*HZ/100) { + barrier(); + cpu_relax(); + } +#endif + /* + * Only the values that we read from the RTC are set. We leave + * tm_wday, tm_yday and tm_isdst untouched. Even though the + * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated + * by the RTC when initially set to a non-zero value. + */ + spin_lock_irq(&rtc_lock); + rtc_tm->tm_sec = READ_SECONDS; + rtc_tm->tm_min = READ_MINUTES; + rtc_tm->tm_hour = READ_HOURS; + rtc_tm->tm_wday = READ_WEEK; + rtc_tm->tm_mday = READ_DAY; + rtc_tm->tm_mon = READ_MONTH; + rtc_tm->tm_year = READ_YEAR - epoch; + spin_unlock_irq(&rtc_lock); + + /* + * 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 sh03_get_rtc_alm_time(struct rtc_time *alm_tm) +{ + /* + * 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); + SELECT_BANK(RTC_BANK1); + alm_tm->tm_sec = READ_SECONDS; + alm_tm->tm_min = READ_MINUTES; + alm_tm->tm_hour = READ_HOURS; + alm_tm->tm_wday = READ_WEEK; + alm_tm->tm_mday = READ_DAY; + SELECT_BANK(RTC_BANK0); + spin_unlock_irq(&rtc_lock); +} + +#ifdef SH03_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 sh03_mask_rtc_irq_bit(unsigned int bit) +{ + unsigned char val; + + spin_lock_irq(&rtc_lock); + switch(bit) { + case RTC_AIE_OFF: + SELECT_BANK(RTC_BANK1); + val = READ_ATCTL; + val &= ~RTC_AIE; + WRITE_ATCTL(val); + SELECT_BANK(RTC_BANK0); + break; + case RTC_PIE_OFF: + SELECT_BANK(RTC_BANK2); + val = READ_TMCTL; + val &= ~RTC_TIE; + WRITE_TMCTL(val); + SELECT_BANK(RTC_BANK0); + break; + } + + rtc_irq_data = 0; + spin_unlock_irq(&rtc_lock); +} + +static void sh03_set_rtc_irq_bit(unsigned int bit) +{ + unsigned char val; + + spin_lock_irq(&rtc_lock); + switch(bit) { + case RTC_AIE_ON: + SELECT_BANK(RTC_BANK1); + val = READ_ATCTL; + val |= RTC_AIE; + WRITE_ATCTL(val); + SELECT_BANK(RTC_BANK0); + break; + case RTC_PIE_ON: + SELECT_BANK(RTC_BANK2); + val = READ_TMCTL; + val |= RTC_TIE; + WRITE_TMCTL(val); + SELECT_BANK(RTC_BANK0); + break; + } + + rtc_irq_data = 0; + spin_unlock_irq(&rtc_lock); +} +#endif + +MODULE_AUTHOR("Saito.K Interface Corporation"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_MISCDEV(RTC_MINOR); + |