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Message-ID: <20191023152332.GR3125@piout.net>
Date: Wed, 23 Oct 2019 17:23:32 +0200
From: Alexandre Belloni <alexandre.belloni@...tlin.com>
To: Arnd Bergmann <arnd@...db.de>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
linux-rtc@...r.kernel.org, Alessandro Zummo <a.zummo@...ertech.it>,
Richard Henderson <rth@...ddle.net>,
Ivan Kokshaysky <ink@...assic.park.msu.ru>,
Matt Turner <mattst88@...il.com>, linux-alpha@...r.kernel.org,
Paul Gortmaker <paul.gortmaker@...driver.com>,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] rtc/alpha: remove legacy rtc driver
On 23/10/2019 17:01:59+0200, Arnd Bergmann wrote:
> The old drivers/char/rtc.c driver was originally the implementation
> for x86 PCs but got subsequently replaced by the rtc class driver
> on all architectures except alpha.
>
> Move alpha over to the portable driver and remove the old one
> for good.
>
> The CONFIG_JS_RTC option was only ever used on SPARC32 but
> has not been available for many years, this was used to build
> the same rtc driver with a different module name.
>
> Cc: Richard Henderson <rth@...ddle.net>
> Cc: Ivan Kokshaysky <ink@...assic.park.msu.ru>
> Cc: Matt Turner <mattst88@...il.com>
> Cc: linux-alpha@...r.kernel.org
> Cc: Paul Gortmaker <paul.gortmaker@...driver.com>
> Signed-off-by: Arnd Bergmann <arnd@...db.de>
Acked-by: Alexandre Belloni <alexandre.belloni@...tlin.com>
> ---
> This was last discussed in early 2018 in
> https://lore.kernel.org/lkml/CAK8P3a0QZNY+K+V1HG056xCerz=_L2jh5UfZ+2LWkDqkw5Zznw@mail.gmail.com/
>
> Nobody ever replied there, so let's try this instead.
> If there is any reason to keep the driver after all,
> please let us know.
> ---
> arch/alpha/configs/defconfig | 3 +-
> drivers/char/Kconfig | 56 --
> drivers/char/Makefile | 4 -
> drivers/char/rtc.c | 1311 ----------------------------------
> 4 files changed, 2 insertions(+), 1372 deletions(-)
> delete mode 100644 drivers/char/rtc.c
>
> diff --git a/arch/alpha/configs/defconfig b/arch/alpha/configs/defconfig
> index f4ec420d7f2d..e10c1be3c0d1 100644
> --- a/arch/alpha/configs/defconfig
> +++ b/arch/alpha/configs/defconfig
> @@ -53,7 +53,8 @@ CONFIG_NET_PCI=y
> CONFIG_YELLOWFIN=y
> CONFIG_SERIAL_8250=y
> CONFIG_SERIAL_8250_CONSOLE=y
> -CONFIG_RTC=y
> +CONFIG_RTC_CLASS=y
> +CONFIG_RTC_DRV_CMOS=y
> CONFIG_EXT2_FS=y
> CONFIG_REISERFS_FS=m
> CONFIG_ISO9660_FS=y
> diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
> index dabbf3f519c6..c2ac4f257c82 100644
> --- a/drivers/char/Kconfig
> +++ b/drivers/char/Kconfig
> @@ -243,62 +243,6 @@ config NVRAM
> To compile this driver as a module, choose M here: the
> module will be called nvram.
>
> -#
> -# These legacy RTC drivers just cause too many conflicts with the generic
> -# RTC framework ... let's not even try to coexist any more.
> -#
> -if RTC_LIB=n
> -
> -config RTC
> - tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
> - depends on ALPHA
> - ---help---
> - If you say Y here and create a character special file /dev/rtc with
> - major number 10 and minor number 135 using mknod ("man mknod"), you
> - will get access to the real time clock (or hardware clock) built
> - into your computer.
> -
> - Every PC has such a clock built in. It can be used to generate
> - signals from as low as 1Hz up to 8192Hz, and can also be used
> - as a 24 hour alarm. It reports status information via the file
> - /proc/driver/rtc and its behaviour is set by various ioctls on
> - /dev/rtc.
> -
> - If you run Linux on a multiprocessor machine and said Y to
> - "Symmetric Multi Processing" above, you should say Y here to read
> - and set the RTC in an SMP compatible fashion.
> -
> - If you think you have a use for such a device (such as periodic data
> - sampling), then say Y here, and read <file:Documentation/admin-guide/rtc.rst>
> - for details.
> -
> - To compile this driver as a module, choose M here: the
> - module will be called rtc.
> -
> -config JS_RTC
> - tristate "Enhanced Real Time Clock Support"
> - depends on SPARC32 && PCI
> - ---help---
> - If you say Y here and create a character special file /dev/rtc with
> - major number 10 and minor number 135 using mknod ("man mknod"), you
> - will get access to the real time clock (or hardware clock) built
> - into your computer.
> -
> - Every PC has such a clock built in. It can be used to generate
> - signals from as low as 1Hz up to 8192Hz, and can also be used
> - as a 24 hour alarm. It reports status information via the file
> - /proc/driver/rtc and its behaviour is set by various ioctls on
> - /dev/rtc.
> -
> - If you think you have a use for such a device (such as periodic data
> - sampling), then say Y here, and read <file:Documentation/admin-guide/rtc.rst>
> - for details.
> -
> - To compile this driver as a module, choose M here: the
> - module will be called js-rtc.
> -
> -endif # RTC_LIB
> -
> config DTLK
> tristate "Double Talk PC internal speech card support"
> depends on ISA
> diff --git a/drivers/char/Makefile b/drivers/char/Makefile
> index abe3138b1f5a..ffce287ef415 100644
> --- a/drivers/char/Makefile
> +++ b/drivers/char/Makefile
> @@ -20,7 +20,6 @@ obj-$(CONFIG_APM_EMULATION) += apm-emulation.o
> obj-$(CONFIG_DTLK) += dtlk.o
> obj-$(CONFIG_APPLICOM) += applicom.o
> obj-$(CONFIG_SONYPI) += sonypi.o
> -obj-$(CONFIG_RTC) += rtc.o
> obj-$(CONFIG_HPET) += hpet.o
> obj-$(CONFIG_XILINX_HWICAP) += xilinx_hwicap/
> obj-$(CONFIG_NVRAM) += nvram.o
> @@ -45,9 +44,6 @@ obj-$(CONFIG_TCG_TPM) += tpm/
>
> obj-$(CONFIG_PS3_FLASH) += ps3flash.o
>
> -obj-$(CONFIG_JS_RTC) += js-rtc.o
> -js-rtc-y = rtc.o
> -
> obj-$(CONFIG_XILLYBUS) += xillybus/
> obj-$(CONFIG_POWERNV_OP_PANEL) += powernv-op-panel.o
> obj-$(CONFIG_ADI) += adi.o
> diff --git a/drivers/char/rtc.c b/drivers/char/rtc.c
> deleted file mode 100644
> index 3b91184b77ae..000000000000
> --- a/drivers/char/rtc.c
> +++ /dev/null
> @@ -1,1311 +0,0 @@
> -// SPDX-License-Identifier: GPL-2.0-or-later
> -/*
> - * Real Time Clock interface for Linux
> - *
> - * Copyright (C) 1996 Paul Gortmaker
> - *
> - * 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.
> - *
> - * 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
> - * 1.12a Maciej W. Rozycki: Handle memory-mapped chips properly.
> - * 1.12ac Alan Cox: Allow read access to the day of week register
> - * 1.12b David John: Remove calls to the BKL.
> - */
> -
> -#define RTC_VERSION "1.12b"
> -
> -/*
> - * 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
> - * kernel/time/ntp.c vs. this driver.)
> - */
> -
> -#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>
> -#include <linux/mc146818rtc.h>
> -#include <linux/init.h>
> -#include <linux/poll.h>
> -#include <linux/proc_fs.h>
> -#include <linux/seq_file.h>
> -#include <linux/spinlock.h>
> -#include <linux/sched/signal.h>
> -#include <linux/sysctl.h>
> -#include <linux/wait.h>
> -#include <linux/bcd.h>
> -#include <linux/delay.h>
> -#include <linux/uaccess.h>
> -#include <linux/ratelimit.h>
> -
> -#include <asm/current.h>
> -
> -#ifdef CONFIG_X86
> -#include <asm/hpet.h>
> -#endif
> -
> -#ifdef CONFIG_SPARC32
> -#include <linux/of.h>
> -#include <linux/of_device.h>
> -#include <asm/io.h>
> -
> -static unsigned long rtc_port;
> -static int rtc_irq;
> -#endif
> -
> -#ifdef CONFIG_HPET_EMULATE_RTC
> -#undef RTC_IRQ
> -#endif
> -
> -#ifdef RTC_IRQ
> -static int rtc_has_irq = 1;
> -#endif
> -
> -#ifndef CONFIG_HPET_EMULATE_RTC
> -#define is_hpet_enabled() 0
> -#define hpet_set_alarm_time(hrs, min, sec) 0
> -#define hpet_set_periodic_freq(arg) 0
> -#define hpet_mask_rtc_irq_bit(arg) 0
> -#define hpet_set_rtc_irq_bit(arg) 0
> -#define hpet_rtc_timer_init() do { } while (0)
> -#define hpet_rtc_dropped_irq() 0
> -#define hpet_register_irq_handler(h) ({ 0; })
> -#define hpet_unregister_irq_handler(h) ({ 0; })
> -#ifdef RTC_IRQ
> -static irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id)
> -{
> - return 0;
> -}
> -#endif
> -#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 *rtc_async_queue;
> -
> -static DECLARE_WAIT_QUEUE_HEAD(rtc_wait);
> -
> -#ifdef RTC_IRQ
> -static void rtc_dropped_irq(struct timer_list *unused);
> -
> -static DEFINE_TIMER(rtc_irq_timer, rtc_dropped_irq);
> -#endif
> -
> -static ssize_t rtc_read(struct file *file, char __user *buf,
> - size_t count, loff_t *ppos);
> -
> -static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
> -static void rtc_get_rtc_time(struct rtc_time *rtc_tm);
> -
> -#ifdef RTC_IRQ
> -static __poll_t rtc_poll(struct file *file, poll_table *wait);
> -#endif
> -
> -static void get_rtc_alm_time(struct rtc_time *alm_tm);
> -#ifdef RTC_IRQ
> -static void set_rtc_irq_bit_locked(unsigned char bit);
> -static void mask_rtc_irq_bit_locked(unsigned char bit);
> -
> -static inline void set_rtc_irq_bit(unsigned char bit)
> -{
> - spin_lock_irq(&rtc_lock);
> - set_rtc_irq_bit_locked(bit);
> - spin_unlock_irq(&rtc_lock);
> -}
> -
> -static void mask_rtc_irq_bit(unsigned char bit)
> -{
> - spin_lock_irq(&rtc_lock);
> - mask_rtc_irq_bit_locked(bit);
> - spin_unlock_irq(&rtc_lock);
> -}
> -#endif
> -
> -#ifdef CONFIG_PROC_FS
> -static int rtc_proc_show(struct seq_file *seq, void *v);
> -#endif
> -
> -/*
> - * 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 spin lock rtc_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; /* bitmapped status byte. */
> -static unsigned long rtc_freq; /* Current periodic IRQ rate */
> -static unsigned long rtc_irq_data; /* our output to the world */
> -static unsigned long rtc_max_user_freq = 64; /* > this, need CAP_SYS_RESOURCE */
> -
> -/*
> - * 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};
> -
> -/*
> - * Returns true if a clock update is in progress
> - */
> -static inline unsigned char rtc_is_updating(void)
> -{
> - unsigned long flags;
> - unsigned char uip;
> -
> - spin_lock_irqsave(&rtc_lock, flags);
> - uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP);
> - spin_unlock_irqrestore(&rtc_lock, flags);
> - return uip;
> -}
> -
> -#ifdef RTC_IRQ
> -/*
> - * A very tiny interrupt handler. It runs with interrupts disabled,
> - * 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.)
> - */
> -
> -static irqreturn_t rtc_interrupt(int irq, void *dev_id)
> -{
> - /*
> - * 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;
> - if (is_hpet_enabled()) {
> - /*
> - * In this case it is HPET RTC interrupt handler
> - * calling us, with the interrupt information
> - * passed as arg1, instead of irq.
> - */
> - rtc_irq_data |= (unsigned long)irq & 0xF0;
> - } else {
> - rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0);
> - }
> -
> - if (rtc_status & RTC_TIMER_ON)
> - mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100);
> -
> - spin_unlock(&rtc_lock);
> -
> - wake_up_interruptible(&rtc_wait);
> -
> - kill_fasync(&rtc_async_queue, SIGIO, POLL_IN);
> -
> - return IRQ_HANDLED;
> -}
> -#endif
> -
> -/*
> - * sysctl-tuning infrastructure.
> - */
> -static struct ctl_table rtc_table[] = {
> - {
> - .procname = "max-user-freq",
> - .data = &rtc_max_user_freq,
> - .maxlen = sizeof(int),
> - .mode = 0644,
> - .proc_handler = proc_dointvec,
> - },
> - { }
> -};
> -
> -static struct ctl_table rtc_root[] = {
> - {
> - .procname = "rtc",
> - .mode = 0555,
> - .child = rtc_table,
> - },
> - { }
> -};
> -
> -static struct ctl_table dev_root[] = {
> - {
> - .procname = "dev",
> - .mode = 0555,
> - .child = rtc_root,
> - },
> - { }
> -};
> -
> -static struct ctl_table_header *sysctl_header;
> -
> -static int __init init_sysctl(void)
> -{
> - sysctl_header = register_sysctl_table(dev_root);
> - 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 rtc_read(struct file *file, char __user *buf,
> - size_t count, loff_t *ppos)
> -{
> -#ifndef RTC_IRQ
> - return -EIO;
> -#else
> - DECLARE_WAITQUEUE(wait, current);
> - unsigned long data;
> - ssize_t retval;
> -
> - if (rtc_has_irq == 0)
> - return -EIO;
> -
> - /*
> - * Historically this function used to assume that sizeof(unsigned long)
> - * is the same in userspace and kernelspace. This lead to problems
> - * for configurations with multiple ABIs such a the MIPS o32 and 64
> - * ABIs supported on the same kernel. So now we support read of both
> - * 4 and 8 bytes and assume that's the sizeof(unsigned long) in the
> - * userspace ABI.
> - */
> - if (count != sizeof(unsigned int) && count != sizeof(unsigned long))
> - return -EINVAL;
> -
> - add_wait_queue(&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 int)) {
> - retval = put_user(data,
> - (unsigned int __user *)buf) ?: sizeof(int);
> - } else {
> - retval = put_user(data,
> - (unsigned long __user *)buf) ?: sizeof(long);
> - }
> - if (!retval)
> - retval = count;
> - out:
> - __set_current_state(TASK_RUNNING);
> - remove_wait_queue(&rtc_wait, &wait);
> -
> - return retval;
> -#endif
> -}
> -
> -static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel)
> -{
> - struct rtc_time wtime;
> -
> -#ifdef RTC_IRQ
> - if (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 RTC_IRQ
> - case RTC_AIE_OFF: /* Mask alarm int. enab. bit */
> - {
> - mask_rtc_irq_bit(RTC_AIE);
> - return 0;
> - }
> - case RTC_AIE_ON: /* Allow alarm interrupts. */
> - {
> - set_rtc_irq_bit(RTC_AIE);
> - return 0;
> - }
> - case RTC_PIE_OFF: /* Mask periodic int. enab. bit */
> - {
> - /* can be called from isr via rtc_control() */
> - unsigned long flags;
> -
> - spin_lock_irqsave(&rtc_lock, flags);
> - mask_rtc_irq_bit_locked(RTC_PIE);
> - if (rtc_status & RTC_TIMER_ON) {
> - rtc_status &= ~RTC_TIMER_ON;
> - del_timer(&rtc_irq_timer);
> - }
> - spin_unlock_irqrestore(&rtc_lock, flags);
> -
> - return 0;
> - }
> - case RTC_PIE_ON: /* Allow periodic ints */
> - {
> - /* can be called from isr via rtc_control() */
> - unsigned long flags;
> -
> - /*
> - * 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;
> -
> - spin_lock_irqsave(&rtc_lock, flags);
> - if (!(rtc_status & RTC_TIMER_ON)) {
> - mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq +
> - 2*HZ/100);
> - rtc_status |= RTC_TIMER_ON;
> - }
> - set_rtc_irq_bit_locked(RTC_PIE);
> - spin_unlock_irqrestore(&rtc_lock, flags);
> -
> - return 0;
> - }
> - case RTC_UIE_OFF: /* Mask ints from RTC updates. */
> - {
> - mask_rtc_irq_bit(RTC_UIE);
> - return 0;
> - }
> - case RTC_UIE_ON: /* Allow ints for RTC updates. */
> - {
> - set_rtc_irq_bit(RTC_UIE);
> - return 0;
> - }
> -#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));
> - 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 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)
> - sec = bin2bcd(sec);
> - else
> - sec = 0xff;
> -
> - if (min < 60)
> - min = bin2bcd(min);
> - else
> - min = 0xff;
> -
> - if (hrs < 24)
> - hrs = bin2bcd(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;
> -
> - yrs -= epoch;
> - if (yrs > 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) {
> - sec = bin2bcd(sec);
> - min = bin2bcd(min);
> - hrs = bin2bcd(hrs);
> - day = bin2bcd(day);
> - mon = bin2bcd(mon);
> - yrs = bin2bcd(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;
> - /* can be called from isr via rtc_control() */
> - unsigned long flags;
> -
> - /*
> - * 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;
> -
> - rtc_freq = arg;
> -
> - spin_lock_irqsave(&rtc_lock, flags);
> - if (hpet_set_periodic_freq(arg)) {
> - spin_unlock_irqrestore(&rtc_lock, flags);
> - return 0;
> - }
> -
> - 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 long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
> -{
> - long ret;
> - ret = rtc_do_ioctl(cmd, arg, 0);
> - return ret;
> -}
> -
> -/*
> - * 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.
> - */
> -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);
> -
> -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
> -static __poll_t 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 EPOLLIN | EPOLLRDNORM;
> - return 0;
> -}
> -#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
> - .unlocked_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 resource_size_t rtc_size;
> -
> -static struct resource * __init rtc_request_region(resource_size_t size)
> -{
> - struct resource *r;
> -
> - if (RTC_IOMAPPED)
> - r = request_region(RTC_PORT(0), size, "rtc");
> - else
> - r = request_mem_region(RTC_PORT(0), size, "rtc");
> -
> - if (r)
> - rtc_size = size;
> -
> - return r;
> -}
> -
> -static void rtc_release_region(void)
> -{
> - if (RTC_IOMAPPED)
> - release_region(RTC_PORT(0), rtc_size);
> - else
> - release_mem_region(RTC_PORT(0), rtc_size);
> -}
> -
> -static int __init rtc_init(void)
> -{
> -#ifdef CONFIG_PROC_FS
> - struct proc_dir_entry *ent;
> -#endif
> -#if defined(__alpha__) || defined(__mips__)
> - unsigned int year, ctrl;
> - char *guess = NULL;
> -#endif
> -#ifdef CONFIG_SPARC32
> - struct device_node *ebus_dp;
> - struct platform_device *op;
> -#else
> - void *r;
> -#ifdef RTC_IRQ
> - irq_handler_t rtc_int_handler_ptr;
> -#endif
> -#endif
> -
> -#ifdef CONFIG_SPARC32
> - for_each_node_by_name(ebus_dp, "ebus") {
> - struct device_node *dp;
> - for_each_child_of_node(ebus_dp, dp) {
> - if (of_node_name_eq(dp, "rtc")) {
> - op = of_find_device_by_node(dp);
> - if (op) {
> - rtc_port = op->resource[0].start;
> - rtc_irq = op->irqs[0];
> - goto found;
> - }
> - }
> - }
> - }
> - rtc_has_irq = 0;
> - printk(KERN_ERR "rtc_init: no PC rtc found\n");
> - return -EIO;
> -
> -found:
> - if (!rtc_irq) {
> - 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)) {
> - rtc_has_irq = 0;
> - printk(KERN_ERR "rtc: cannot register IRQ %d\n", rtc_irq);
> - return -EIO;
> - }
> -no_irq:
> -#else
> - r = rtc_request_region(RTC_IO_EXTENT);
> -
> - /*
> - * If we've already requested a smaller range (for example, because
> - * PNPBIOS or ACPI told us how the device is configured), the request
> - * above might fail because it's too big.
> - *
> - * If so, request just the range we actually use.
> - */
> - if (!r)
> - r = rtc_request_region(RTC_IO_EXTENT_USED);
> - if (!r) {
> -#ifdef RTC_IRQ
> - rtc_has_irq = 0;
> -#endif
> - 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()) {
> - int err;
> -
> - rtc_int_handler_ptr = hpet_rtc_interrupt;
> - err = hpet_register_irq_handler(rtc_interrupt);
> - if (err != 0) {
> - printk(KERN_WARNING "hpet_register_irq_handler failed "
> - "in rtc_init().");
> - return err;
> - }
> - } else {
> - rtc_int_handler_ptr = rtc_interrupt;
> - }
> -
> - if (request_irq(RTC_IRQ, rtc_int_handler_ptr, 0, "rtc", NULL)) {
> - /* Yeah right, seeing as irq 8 doesn't even hit the bus. */
> - rtc_has_irq = 0;
> - printk(KERN_ERR "rtc: IRQ %d is not free.\n", RTC_IRQ);
> - rtc_release_region();
> -
> - return -EIO;
> - }
> - hpet_rtc_timer_init();
> -
> -#endif
> -
> -#endif /* CONFIG_SPARC32 vs. others */
> -
> - if (misc_register(&rtc_dev)) {
> -#ifdef RTC_IRQ
> - free_irq(RTC_IRQ, NULL);
> - hpet_unregister_irq_handler(rtc_interrupt);
> - rtc_has_irq = 0;
> -#endif
> - rtc_release_region();
> - return -ENODEV;
> - }
> -
> -#ifdef CONFIG_PROC_FS
> - ent = proc_create_single("driver/rtc", 0, NULL, rtc_proc_show);
> - if (!ent)
> - printk(KERN_WARNING "rtc: Failed to register with procfs.\n");
> -#endif
> -
> -#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)
> - year = bcd2bin(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;
> -
> - spin_lock_irq(&rtc_lock);
> - rtc_freq = 1024;
> - if (!hpet_set_periodic_freq(rtc_freq)) {
> - /*
> - * Initialize periodic frequency 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 CONFIG_SPARC32
> - if (rtc_has_irq)
> - free_irq(rtc_irq, &rtc_port);
> -#else
> - rtc_release_region();
> -#ifdef RTC_IRQ
> - if (rtc_has_irq) {
> - free_irq(RTC_IRQ, NULL);
> - hpet_unregister_irq_handler(hpet_rtc_interrupt);
> - }
> -#endif
> -#endif /* CONFIG_SPARC32 */
> -}
> -
> -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(struct timer_list *unused)
> -{
> - 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_ratelimited(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
> -
> -#ifdef CONFIG_PROC_FS
> -/*
> - * 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: %ptRt\n"
> - "rtc_date\t: %ptRd\n"
> - "rtc_epoch\t: %04lu\n",
> - &tm, &tm, 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
> -}
> -#endif
> -
> -static 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 &&
> - time_before(jiffies, uip_watchdog + 2*HZ/100))
> - 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) {
> - rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
> - rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
> - rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
> - rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
> - rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
> - rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
> - rtc_tm->tm_wday = bcd2bin(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;
> - */
> - rtc_tm->tm_year += epoch - 1900;
> - if (rtc_tm->tm_year <= 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) {
> - alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
> - alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
> - alm_tm->tm_hour = bcd2bin(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);
> --
> 2.20.0
>
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
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