![David Brownell](/assets/img/avatar_default.png)
This fixes kernel http://bugzilla.kernel.org/show_bug.cgi?id=11112 (bogus RTC update IRQs reported) for rtc-cmos, in two ways: - When HPET is stealing the IRQs, use the first IRQ to grab the seconds counter which will be monitored (instead of using whatever was previously in that memory); - In sane IRQ handling modes, scrub out old IRQ status before enabling IRQs. That latter is done by tightening up IRQ handling for rtc-cmos everywhere, also ensuring that when HPET is used it's the only thing triggering IRQ reports to userspace; net object shrink. Also fix a bogus HPET message related to its RTC emulation. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Report-by: W Unruh <unruh@physics.ubc.ca> Cc: Andrew Victor <avictor.za@gmail.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1037 lines
25 KiB
C
1037 lines
25 KiB
C
/*
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* RTC class driver for "CMOS RTC": PCs, ACPI, etc
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*
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* Copyright (C) 1996 Paul Gortmaker (drivers/char/rtc.c)
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* Copyright (C) 2006 David Brownell (convert to new framework)
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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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/*
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* The original "cmos clock" chip was an MC146818 chip, now obsolete.
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* That defined the register interface now provided by all PCs, some
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* non-PC systems, and incorporated into ACPI. Modern PC chipsets
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* integrate an MC146818 clone in their southbridge, and boards use
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* that instead of discrete clones like the DS12887 or M48T86. There
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* are also clones that connect using the LPC bus.
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*
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* That register API is also used directly by various other drivers
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* (notably for integrated NVRAM), infrastructure (x86 has code to
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* bypass the RTC framework, directly reading the RTC during boot
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* and updating minutes/seconds for systems using NTP synch) and
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* utilities (like userspace 'hwclock', if no /dev node exists).
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*
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* So **ALL** calls to CMOS_READ and CMOS_WRITE must be done with
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* interrupts disabled, holding the global rtc_lock, to exclude those
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* other drivers and utilities on correctly configured systems.
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/spinlock.h>
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#include <linux/platform_device.h>
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#include <linux/mod_devicetable.h>
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/* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
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#include <asm-generic/rtc.h>
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struct cmos_rtc {
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struct rtc_device *rtc;
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struct device *dev;
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int irq;
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struct resource *iomem;
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void (*wake_on)(struct device *);
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void (*wake_off)(struct device *);
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u8 enabled_wake;
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u8 suspend_ctrl;
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/* newer hardware extends the original register set */
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u8 day_alrm;
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u8 mon_alrm;
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u8 century;
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};
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/* both platform and pnp busses use negative numbers for invalid irqs */
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#define is_valid_irq(n) ((n) >= 0)
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static const char driver_name[] = "rtc_cmos";
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/* The RTC_INTR register may have e.g. RTC_PF set even if RTC_PIE is clear;
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* always mask it against the irq enable bits in RTC_CONTROL. Bit values
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* are the same: PF==PIE, AF=AIE, UF=UIE; so RTC_IRQMASK works with both.
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*/
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#define RTC_IRQMASK (RTC_PF | RTC_AF | RTC_UF)
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static inline int is_intr(u8 rtc_intr)
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{
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if (!(rtc_intr & RTC_IRQF))
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return 0;
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return rtc_intr & RTC_IRQMASK;
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}
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/*----------------------------------------------------------------*/
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/* Much modern x86 hardware has HPETs (10+ MHz timers) which, because
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* many BIOS programmers don't set up "sane mode" IRQ routing, are mostly
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* used in a broken "legacy replacement" mode. The breakage includes
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* HPET #1 hijacking the IRQ for this RTC, and being unavailable for
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* other (better) use.
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*
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* When that broken mode is in use, platform glue provides a partial
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* emulation of hardware RTC IRQ facilities using HPET #1. We don't
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* want to use HPET for anything except those IRQs though...
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*/
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#ifdef CONFIG_HPET_EMULATE_RTC
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#include <asm/hpet.h>
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#else
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static inline int is_hpet_enabled(void)
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{
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return 0;
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}
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static inline int hpet_mask_rtc_irq_bit(unsigned long mask)
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{
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return 0;
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}
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static inline int hpet_set_rtc_irq_bit(unsigned long mask)
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{
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return 0;
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}
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static inline int
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hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec)
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{
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return 0;
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}
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static inline int hpet_set_periodic_freq(unsigned long freq)
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{
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return 0;
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}
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static inline int hpet_rtc_dropped_irq(void)
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{
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return 0;
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}
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static inline int hpet_rtc_timer_init(void)
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{
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return 0;
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}
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extern irq_handler_t hpet_rtc_interrupt;
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static inline int hpet_register_irq_handler(irq_handler_t handler)
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{
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return 0;
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}
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static inline int hpet_unregister_irq_handler(irq_handler_t handler)
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{
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return 0;
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}
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#endif
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/*----------------------------------------------------------------*/
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static int cmos_read_time(struct device *dev, struct rtc_time *t)
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{
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/* REVISIT: if the clock has a "century" register, use
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* that instead of the heuristic in get_rtc_time().
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* That'll make Y3K compatility (year > 2070) easy!
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*/
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get_rtc_time(t);
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return 0;
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}
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static int cmos_set_time(struct device *dev, struct rtc_time *t)
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{
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/* REVISIT: set the "century" register if available
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*
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* NOTE: this ignores the issue whereby updating the seconds
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* takes effect exactly 500ms after we write the register.
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* (Also queueing and other delays before we get this far.)
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*/
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return set_rtc_time(t);
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}
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static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
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{
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struct cmos_rtc *cmos = dev_get_drvdata(dev);
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unsigned char rtc_control;
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if (!is_valid_irq(cmos->irq))
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return -EIO;
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/* Basic alarms only support hour, minute, and seconds fields.
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* Some also support day and month, for alarms up to a year in
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* the future.
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*/
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t->time.tm_mday = -1;
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t->time.tm_mon = -1;
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spin_lock_irq(&rtc_lock);
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t->time.tm_sec = CMOS_READ(RTC_SECONDS_ALARM);
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t->time.tm_min = CMOS_READ(RTC_MINUTES_ALARM);
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t->time.tm_hour = CMOS_READ(RTC_HOURS_ALARM);
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if (cmos->day_alrm) {
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/* ignore upper bits on readback per ACPI spec */
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t->time.tm_mday = CMOS_READ(cmos->day_alrm) & 0x3f;
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if (!t->time.tm_mday)
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t->time.tm_mday = -1;
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if (cmos->mon_alrm) {
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t->time.tm_mon = CMOS_READ(cmos->mon_alrm);
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if (!t->time.tm_mon)
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t->time.tm_mon = -1;
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}
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}
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rtc_control = CMOS_READ(RTC_CONTROL);
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spin_unlock_irq(&rtc_lock);
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/* REVISIT this assumes PC style usage: always BCD */
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if (((unsigned)t->time.tm_sec) < 0x60)
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t->time.tm_sec = BCD2BIN(t->time.tm_sec);
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else
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t->time.tm_sec = -1;
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if (((unsigned)t->time.tm_min) < 0x60)
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t->time.tm_min = BCD2BIN(t->time.tm_min);
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else
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t->time.tm_min = -1;
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if (((unsigned)t->time.tm_hour) < 0x24)
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t->time.tm_hour = BCD2BIN(t->time.tm_hour);
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else
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t->time.tm_hour = -1;
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if (cmos->day_alrm) {
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if (((unsigned)t->time.tm_mday) <= 0x31)
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t->time.tm_mday = BCD2BIN(t->time.tm_mday);
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else
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t->time.tm_mday = -1;
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if (cmos->mon_alrm) {
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if (((unsigned)t->time.tm_mon) <= 0x12)
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t->time.tm_mon = BCD2BIN(t->time.tm_mon) - 1;
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else
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t->time.tm_mon = -1;
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}
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}
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t->time.tm_year = -1;
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t->enabled = !!(rtc_control & RTC_AIE);
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t->pending = 0;
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return 0;
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}
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static void cmos_checkintr(struct cmos_rtc *cmos, unsigned char rtc_control)
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{
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unsigned char rtc_intr;
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/* NOTE after changing RTC_xIE bits we always read INTR_FLAGS;
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* allegedly some older rtcs need that to handle irqs properly
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*/
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rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
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if (is_hpet_enabled())
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return;
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rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
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if (is_intr(rtc_intr))
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rtc_update_irq(cmos->rtc, 1, rtc_intr);
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}
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static void cmos_irq_enable(struct cmos_rtc *cmos, unsigned char mask)
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{
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unsigned char rtc_control;
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/* flush any pending IRQ status, notably for update irqs,
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* before we enable new IRQs
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*/
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rtc_control = CMOS_READ(RTC_CONTROL);
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cmos_checkintr(cmos, rtc_control);
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rtc_control |= mask;
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CMOS_WRITE(rtc_control, RTC_CONTROL);
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hpet_set_rtc_irq_bit(mask);
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cmos_checkintr(cmos, rtc_control);
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}
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static void cmos_irq_disable(struct cmos_rtc *cmos, unsigned char mask)
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{
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unsigned char rtc_control;
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rtc_control = CMOS_READ(RTC_CONTROL);
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rtc_control &= ~mask;
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CMOS_WRITE(rtc_control, RTC_CONTROL);
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hpet_mask_rtc_irq_bit(mask);
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cmos_checkintr(cmos, rtc_control);
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}
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static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
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{
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struct cmos_rtc *cmos = dev_get_drvdata(dev);
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unsigned char mon, mday, hrs, min, sec;
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if (!is_valid_irq(cmos->irq))
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return -EIO;
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/* REVISIT this assumes PC style usage: always BCD */
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/* Writing 0xff means "don't care" or "match all". */
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mon = t->time.tm_mon + 1;
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mon = (mon <= 12) ? BIN2BCD(mon) : 0xff;
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mday = t->time.tm_mday;
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mday = (mday >= 1 && mday <= 31) ? BIN2BCD(mday) : 0xff;
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hrs = t->time.tm_hour;
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hrs = (hrs < 24) ? BIN2BCD(hrs) : 0xff;
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min = t->time.tm_min;
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min = (min < 60) ? BIN2BCD(min) : 0xff;
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sec = t->time.tm_sec;
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sec = (sec < 60) ? BIN2BCD(sec) : 0xff;
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spin_lock_irq(&rtc_lock);
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/* next rtc irq must not be from previous alarm setting */
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cmos_irq_disable(cmos, RTC_AIE);
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/* update alarm */
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CMOS_WRITE(hrs, RTC_HOURS_ALARM);
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CMOS_WRITE(min, RTC_MINUTES_ALARM);
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CMOS_WRITE(sec, RTC_SECONDS_ALARM);
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/* the system may support an "enhanced" alarm */
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if (cmos->day_alrm) {
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CMOS_WRITE(mday, cmos->day_alrm);
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if (cmos->mon_alrm)
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CMOS_WRITE(mon, cmos->mon_alrm);
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}
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/* FIXME the HPET alarm glue currently ignores day_alrm
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* and mon_alrm ...
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*/
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hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min, t->time.tm_sec);
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if (t->enabled)
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cmos_irq_enable(cmos, RTC_AIE);
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spin_unlock_irq(&rtc_lock);
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return 0;
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}
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static int cmos_irq_set_freq(struct device *dev, int freq)
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{
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struct cmos_rtc *cmos = dev_get_drvdata(dev);
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int f;
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unsigned long flags;
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if (!is_valid_irq(cmos->irq))
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return -ENXIO;
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/* 0 = no irqs; 1 = 2^15 Hz ... 15 = 2^0 Hz */
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f = ffs(freq);
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if (f-- > 16)
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return -EINVAL;
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f = 16 - f;
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spin_lock_irqsave(&rtc_lock, flags);
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hpet_set_periodic_freq(freq);
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CMOS_WRITE(RTC_REF_CLCK_32KHZ | f, RTC_FREQ_SELECT);
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spin_unlock_irqrestore(&rtc_lock, flags);
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return 0;
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}
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static int cmos_irq_set_state(struct device *dev, int enabled)
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{
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struct cmos_rtc *cmos = dev_get_drvdata(dev);
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unsigned long flags;
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if (!is_valid_irq(cmos->irq))
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return -ENXIO;
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spin_lock_irqsave(&rtc_lock, flags);
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if (enabled)
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cmos_irq_enable(cmos, RTC_PIE);
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else
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cmos_irq_disable(cmos, 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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#if defined(CONFIG_RTC_INTF_DEV) || defined(CONFIG_RTC_INTF_DEV_MODULE)
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static int
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cmos_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
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{
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struct cmos_rtc *cmos = dev_get_drvdata(dev);
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unsigned long flags;
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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_UIE_OFF:
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case RTC_UIE_ON:
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if (!is_valid_irq(cmos->irq))
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return -EINVAL;
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break;
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/* PIE ON/OFF is handled by cmos_irq_set_state() */
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default:
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return -ENOIOCTLCMD;
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}
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spin_lock_irqsave(&rtc_lock, flags);
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switch (cmd) {
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case RTC_AIE_OFF: /* alarm off */
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cmos_irq_disable(cmos, RTC_AIE);
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break;
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case RTC_AIE_ON: /* alarm on */
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cmos_irq_enable(cmos, RTC_AIE);
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break;
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case RTC_UIE_OFF: /* update off */
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cmos_irq_disable(cmos, RTC_UIE);
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break;
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case RTC_UIE_ON: /* update on */
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cmos_irq_enable(cmos, RTC_UIE);
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break;
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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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#else
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#define cmos_rtc_ioctl NULL
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#endif
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#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
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static int cmos_procfs(struct device *dev, struct seq_file *seq)
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{
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struct cmos_rtc *cmos = dev_get_drvdata(dev);
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unsigned char rtc_control, valid;
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spin_lock_irq(&rtc_lock);
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rtc_control = CMOS_READ(RTC_CONTROL);
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valid = CMOS_READ(RTC_VALID);
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spin_unlock_irq(&rtc_lock);
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/* NOTE: at least ICH6 reports battery status using a different
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* (non-RTC) bit; and SQWE is ignored on many current systems.
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*/
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return seq_printf(seq,
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"periodic_IRQ\t: %s\n"
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"update_IRQ\t: %s\n"
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"HPET_emulated\t: %s\n"
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// "square_wave\t: %s\n"
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// "BCD\t\t: %s\n"
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"DST_enable\t: %s\n"
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"periodic_freq\t: %d\n"
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"batt_status\t: %s\n",
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(rtc_control & RTC_PIE) ? "yes" : "no",
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(rtc_control & RTC_UIE) ? "yes" : "no",
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is_hpet_enabled() ? "yes" : "no",
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// (rtc_control & RTC_SQWE) ? "yes" : "no",
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// (rtc_control & RTC_DM_BINARY) ? "no" : "yes",
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(rtc_control & RTC_DST_EN) ? "yes" : "no",
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cmos->rtc->irq_freq,
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(valid & RTC_VRT) ? "okay" : "dead");
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}
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#else
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#define cmos_procfs NULL
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#endif
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static const struct rtc_class_ops cmos_rtc_ops = {
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.ioctl = cmos_rtc_ioctl,
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.read_time = cmos_read_time,
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.set_time = cmos_set_time,
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.read_alarm = cmos_read_alarm,
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.set_alarm = cmos_set_alarm,
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.proc = cmos_procfs,
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.irq_set_freq = cmos_irq_set_freq,
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.irq_set_state = cmos_irq_set_state,
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};
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/*----------------------------------------------------------------*/
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/*
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* All these chips have at least 64 bytes of address space, shared by
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* RTC registers and NVRAM. Most of those bytes of NVRAM are used
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* by boot firmware. Modern chips have 128 or 256 bytes.
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*/
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#define NVRAM_OFFSET (RTC_REG_D + 1)
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static ssize_t
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cmos_nvram_read(struct kobject *kobj, struct bin_attribute *attr,
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char *buf, loff_t off, size_t count)
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{
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int retval;
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if (unlikely(off >= attr->size))
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return 0;
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if ((off + count) > attr->size)
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count = attr->size - off;
|
|
|
|
spin_lock_irq(&rtc_lock);
|
|
for (retval = 0, off += NVRAM_OFFSET; count--; retval++, off++)
|
|
*buf++ = CMOS_READ(off);
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
return retval;
|
|
}
|
|
|
|
static ssize_t
|
|
cmos_nvram_write(struct kobject *kobj, struct bin_attribute *attr,
|
|
char *buf, loff_t off, size_t count)
|
|
{
|
|
struct cmos_rtc *cmos;
|
|
int retval;
|
|
|
|
cmos = dev_get_drvdata(container_of(kobj, struct device, kobj));
|
|
if (unlikely(off >= attr->size))
|
|
return -EFBIG;
|
|
if ((off + count) > attr->size)
|
|
count = attr->size - off;
|
|
|
|
/* NOTE: on at least PCs and Ataris, the boot firmware uses a
|
|
* checksum on part of the NVRAM data. That's currently ignored
|
|
* here. If userspace is smart enough to know what fields of
|
|
* NVRAM to update, updating checksums is also part of its job.
|
|
*/
|
|
spin_lock_irq(&rtc_lock);
|
|
for (retval = 0, off += NVRAM_OFFSET; count--; retval++, off++) {
|
|
/* don't trash RTC registers */
|
|
if (off == cmos->day_alrm
|
|
|| off == cmos->mon_alrm
|
|
|| off == cmos->century)
|
|
buf++;
|
|
else
|
|
CMOS_WRITE(*buf++, off);
|
|
}
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
return retval;
|
|
}
|
|
|
|
static struct bin_attribute nvram = {
|
|
.attr = {
|
|
.name = "nvram",
|
|
.mode = S_IRUGO | S_IWUSR,
|
|
.owner = THIS_MODULE,
|
|
},
|
|
|
|
.read = cmos_nvram_read,
|
|
.write = cmos_nvram_write,
|
|
/* size gets set up later */
|
|
};
|
|
|
|
/*----------------------------------------------------------------*/
|
|
|
|
static struct cmos_rtc cmos_rtc;
|
|
|
|
static irqreturn_t cmos_interrupt(int irq, void *p)
|
|
{
|
|
u8 irqstat;
|
|
u8 rtc_control;
|
|
|
|
spin_lock(&rtc_lock);
|
|
|
|
/* When the HPET interrupt handler calls us, the interrupt
|
|
* status is passed as arg1 instead of the irq number. But
|
|
* always clear irq status, even when HPET is in the way.
|
|
*
|
|
* Note that HPET and RTC are almost certainly out of phase,
|
|
* giving different IRQ status ...
|
|
*/
|
|
irqstat = CMOS_READ(RTC_INTR_FLAGS);
|
|
rtc_control = CMOS_READ(RTC_CONTROL);
|
|
if (is_hpet_enabled())
|
|
irqstat = (unsigned long)irq & 0xF0;
|
|
irqstat &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
|
|
|
|
/* All Linux RTC alarms should be treated as if they were oneshot.
|
|
* Similar code may be needed in system wakeup paths, in case the
|
|
* alarm woke the system.
|
|
*/
|
|
if (irqstat & RTC_AIE) {
|
|
rtc_control &= ~RTC_AIE;
|
|
CMOS_WRITE(rtc_control, RTC_CONTROL);
|
|
hpet_mask_rtc_irq_bit(RTC_AIE);
|
|
|
|
CMOS_READ(RTC_INTR_FLAGS);
|
|
}
|
|
spin_unlock(&rtc_lock);
|
|
|
|
if (is_intr(irqstat)) {
|
|
rtc_update_irq(p, 1, irqstat);
|
|
return IRQ_HANDLED;
|
|
} else
|
|
return IRQ_NONE;
|
|
}
|
|
|
|
#ifdef CONFIG_PNP
|
|
#define INITSECTION
|
|
|
|
#else
|
|
#define INITSECTION __init
|
|
#endif
|
|
|
|
static int INITSECTION
|
|
cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
|
|
{
|
|
struct cmos_rtc_board_info *info = dev->platform_data;
|
|
int retval = 0;
|
|
unsigned char rtc_control;
|
|
unsigned address_space;
|
|
|
|
/* there can be only one ... */
|
|
if (cmos_rtc.dev)
|
|
return -EBUSY;
|
|
|
|
if (!ports)
|
|
return -ENODEV;
|
|
|
|
/* Claim I/O ports ASAP, minimizing conflict with legacy driver.
|
|
*
|
|
* REVISIT non-x86 systems may instead use memory space resources
|
|
* (needing ioremap etc), not i/o space resources like this ...
|
|
*/
|
|
ports = request_region(ports->start,
|
|
ports->end + 1 - ports->start,
|
|
driver_name);
|
|
if (!ports) {
|
|
dev_dbg(dev, "i/o registers already in use\n");
|
|
return -EBUSY;
|
|
}
|
|
|
|
cmos_rtc.irq = rtc_irq;
|
|
cmos_rtc.iomem = ports;
|
|
|
|
/* Heuristic to deduce NVRAM size ... do what the legacy NVRAM
|
|
* driver did, but don't reject unknown configs. Old hardware
|
|
* won't address 128 bytes, and for now we ignore the way newer
|
|
* chips can address 256 bytes (using two more i/o ports).
|
|
*/
|
|
#if defined(CONFIG_ATARI)
|
|
address_space = 64;
|
|
#elif defined(__i386__) || defined(__x86_64__) || defined(__arm__)
|
|
address_space = 128;
|
|
#else
|
|
#warning Assuming 128 bytes of RTC+NVRAM address space, not 64 bytes.
|
|
address_space = 128;
|
|
#endif
|
|
|
|
/* For ACPI systems extension info comes from the FADT. On others,
|
|
* board specific setup provides it as appropriate. Systems where
|
|
* the alarm IRQ isn't automatically a wakeup IRQ (like ACPI, and
|
|
* some almost-clones) can provide hooks to make that behave.
|
|
*
|
|
* Note that ACPI doesn't preclude putting these registers into
|
|
* "extended" areas of the chip, including some that we won't yet
|
|
* expect CMOS_READ and friends to handle.
|
|
*/
|
|
if (info) {
|
|
if (info->rtc_day_alarm && info->rtc_day_alarm < 128)
|
|
cmos_rtc.day_alrm = info->rtc_day_alarm;
|
|
if (info->rtc_mon_alarm && info->rtc_mon_alarm < 128)
|
|
cmos_rtc.mon_alrm = info->rtc_mon_alarm;
|
|
if (info->rtc_century && info->rtc_century < 128)
|
|
cmos_rtc.century = info->rtc_century;
|
|
|
|
if (info->wake_on && info->wake_off) {
|
|
cmos_rtc.wake_on = info->wake_on;
|
|
cmos_rtc.wake_off = info->wake_off;
|
|
}
|
|
}
|
|
|
|
cmos_rtc.rtc = rtc_device_register(driver_name, dev,
|
|
&cmos_rtc_ops, THIS_MODULE);
|
|
if (IS_ERR(cmos_rtc.rtc)) {
|
|
retval = PTR_ERR(cmos_rtc.rtc);
|
|
goto cleanup0;
|
|
}
|
|
|
|
cmos_rtc.dev = dev;
|
|
dev_set_drvdata(dev, &cmos_rtc);
|
|
rename_region(ports, cmos_rtc.rtc->dev.bus_id);
|
|
|
|
spin_lock_irq(&rtc_lock);
|
|
|
|
/* force periodic irq to CMOS reset default of 1024Hz;
|
|
*
|
|
* REVISIT it's been reported that at least one x86_64 ALI mobo
|
|
* doesn't use 32KHz here ... for portability we might need to
|
|
* do something about other clock frequencies.
|
|
*/
|
|
cmos_rtc.rtc->irq_freq = 1024;
|
|
hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
|
|
CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
|
|
|
|
/* disable irqs */
|
|
cmos_irq_disable(&cmos_rtc, RTC_PIE | RTC_AIE | RTC_UIE);
|
|
|
|
rtc_control = CMOS_READ(RTC_CONTROL);
|
|
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
/* FIXME teach the alarm code how to handle binary mode;
|
|
* <asm-generic/rtc.h> doesn't know 12-hour mode either.
|
|
*/
|
|
if (!(rtc_control & RTC_24H) || (rtc_control & (RTC_DM_BINARY))) {
|
|
dev_dbg(dev, "only 24-hr BCD mode supported\n");
|
|
retval = -ENXIO;
|
|
goto cleanup1;
|
|
}
|
|
|
|
if (is_valid_irq(rtc_irq)) {
|
|
irq_handler_t rtc_cmos_int_handler;
|
|
|
|
if (is_hpet_enabled()) {
|
|
int err;
|
|
|
|
rtc_cmos_int_handler = hpet_rtc_interrupt;
|
|
err = hpet_register_irq_handler(cmos_interrupt);
|
|
if (err != 0) {
|
|
printk(KERN_WARNING "hpet_register_irq_handler "
|
|
" failed in rtc_init().");
|
|
goto cleanup1;
|
|
}
|
|
} else
|
|
rtc_cmos_int_handler = cmos_interrupt;
|
|
|
|
retval = request_irq(rtc_irq, rtc_cmos_int_handler,
|
|
IRQF_DISABLED, cmos_rtc.rtc->dev.bus_id,
|
|
cmos_rtc.rtc);
|
|
if (retval < 0) {
|
|
dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);
|
|
goto cleanup1;
|
|
}
|
|
}
|
|
hpet_rtc_timer_init();
|
|
|
|
/* export at least the first block of NVRAM */
|
|
nvram.size = address_space - NVRAM_OFFSET;
|
|
retval = sysfs_create_bin_file(&dev->kobj, &nvram);
|
|
if (retval < 0) {
|
|
dev_dbg(dev, "can't create nvram file? %d\n", retval);
|
|
goto cleanup2;
|
|
}
|
|
|
|
pr_info("%s: alarms up to one %s%s%s\n",
|
|
cmos_rtc.rtc->dev.bus_id,
|
|
is_valid_irq(rtc_irq)
|
|
? (cmos_rtc.mon_alrm
|
|
? "year"
|
|
: (cmos_rtc.day_alrm
|
|
? "month" : "day"))
|
|
: "no",
|
|
cmos_rtc.century ? ", y3k" : "",
|
|
is_hpet_enabled() ? ", hpet irqs" : "");
|
|
|
|
return 0;
|
|
|
|
cleanup2:
|
|
if (is_valid_irq(rtc_irq))
|
|
free_irq(rtc_irq, cmos_rtc.rtc);
|
|
cleanup1:
|
|
cmos_rtc.dev = NULL;
|
|
rtc_device_unregister(cmos_rtc.rtc);
|
|
cleanup0:
|
|
release_region(ports->start, ports->end + 1 - ports->start);
|
|
return retval;
|
|
}
|
|
|
|
static void cmos_do_shutdown(void)
|
|
{
|
|
spin_lock_irq(&rtc_lock);
|
|
cmos_irq_disable(&cmos_rtc, RTC_IRQMASK);
|
|
spin_unlock_irq(&rtc_lock);
|
|
}
|
|
|
|
static void __exit cmos_do_remove(struct device *dev)
|
|
{
|
|
struct cmos_rtc *cmos = dev_get_drvdata(dev);
|
|
struct resource *ports;
|
|
|
|
cmos_do_shutdown();
|
|
|
|
sysfs_remove_bin_file(&dev->kobj, &nvram);
|
|
|
|
if (is_valid_irq(cmos->irq)) {
|
|
free_irq(cmos->irq, cmos->rtc);
|
|
hpet_unregister_irq_handler(cmos_interrupt);
|
|
}
|
|
|
|
rtc_device_unregister(cmos->rtc);
|
|
cmos->rtc = NULL;
|
|
|
|
ports = cmos->iomem;
|
|
release_region(ports->start, ports->end + 1 - ports->start);
|
|
cmos->iomem = NULL;
|
|
|
|
cmos->dev = NULL;
|
|
dev_set_drvdata(dev, NULL);
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
|
|
static int cmos_suspend(struct device *dev, pm_message_t mesg)
|
|
{
|
|
struct cmos_rtc *cmos = dev_get_drvdata(dev);
|
|
int do_wake = device_may_wakeup(dev);
|
|
unsigned char tmp;
|
|
|
|
/* only the alarm might be a wakeup event source */
|
|
spin_lock_irq(&rtc_lock);
|
|
cmos->suspend_ctrl = tmp = CMOS_READ(RTC_CONTROL);
|
|
if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
|
|
unsigned char mask;
|
|
|
|
if (do_wake)
|
|
mask = RTC_IRQMASK & ~RTC_AIE;
|
|
else
|
|
mask = RTC_IRQMASK;
|
|
tmp &= ~mask;
|
|
CMOS_WRITE(tmp, RTC_CONTROL);
|
|
hpet_mask_rtc_irq_bit(mask);
|
|
|
|
cmos_checkintr(cmos, tmp);
|
|
}
|
|
spin_unlock_irq(&rtc_lock);
|
|
|
|
if (tmp & RTC_AIE) {
|
|
cmos->enabled_wake = 1;
|
|
if (cmos->wake_on)
|
|
cmos->wake_on(dev);
|
|
else
|
|
enable_irq_wake(cmos->irq);
|
|
}
|
|
|
|
pr_debug("%s: suspend%s, ctrl %02x\n",
|
|
cmos_rtc.rtc->dev.bus_id,
|
|
(tmp & RTC_AIE) ? ", alarm may wake" : "",
|
|
tmp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int cmos_resume(struct device *dev)
|
|
{
|
|
struct cmos_rtc *cmos = dev_get_drvdata(dev);
|
|
unsigned char tmp = cmos->suspend_ctrl;
|
|
|
|
/* re-enable any irqs previously active */
|
|
if (tmp & RTC_IRQMASK) {
|
|
unsigned char mask;
|
|
|
|
if (cmos->enabled_wake) {
|
|
if (cmos->wake_off)
|
|
cmos->wake_off(dev);
|
|
else
|
|
disable_irq_wake(cmos->irq);
|
|
cmos->enabled_wake = 0;
|
|
}
|
|
|
|
spin_lock_irq(&rtc_lock);
|
|
do {
|
|
CMOS_WRITE(tmp, RTC_CONTROL);
|
|
hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
|
|
|
|
mask = CMOS_READ(RTC_INTR_FLAGS);
|
|
mask &= (tmp & RTC_IRQMASK) | RTC_IRQF;
|
|
if (!is_hpet_enabled() || !is_intr(mask))
|
|
break;
|
|
|
|
/* force one-shot behavior if HPET blocked
|
|
* the wake alarm's irq
|
|
*/
|
|
rtc_update_irq(cmos->rtc, 1, mask);
|
|
tmp &= ~RTC_AIE;
|
|
hpet_mask_rtc_irq_bit(RTC_AIE);
|
|
} while (mask & RTC_AIE);
|
|
spin_unlock_irq(&rtc_lock);
|
|
}
|
|
|
|
pr_debug("%s: resume, ctrl %02x\n",
|
|
cmos_rtc.rtc->dev.bus_id,
|
|
tmp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#else
|
|
#define cmos_suspend NULL
|
|
#define cmos_resume NULL
|
|
#endif
|
|
|
|
/*----------------------------------------------------------------*/
|
|
|
|
/* On non-x86 systems, a "CMOS" RTC lives most naturally on platform_bus.
|
|
* ACPI systems always list these as PNPACPI devices, and pre-ACPI PCs
|
|
* probably list them in similar PNPBIOS tables; so PNP is more common.
|
|
*
|
|
* We don't use legacy "poke at the hardware" probing. Ancient PCs that
|
|
* predate even PNPBIOS should set up platform_bus devices.
|
|
*/
|
|
|
|
#ifdef CONFIG_PNP
|
|
|
|
#include <linux/pnp.h>
|
|
|
|
static int __devinit
|
|
cmos_pnp_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
|
|
{
|
|
/* REVISIT paranoia argues for a shutdown notifier, since PNP
|
|
* drivers can't provide shutdown() methods to disable IRQs.
|
|
* Or better yet, fix PNP to allow those methods...
|
|
*/
|
|
if (pnp_port_start(pnp,0) == 0x70 && !pnp_irq_valid(pnp,0))
|
|
/* Some machines contain a PNP entry for the RTC, but
|
|
* don't define the IRQ. It should always be safe to
|
|
* hardcode it in these cases
|
|
*/
|
|
return cmos_do_probe(&pnp->dev,
|
|
pnp_get_resource(pnp, IORESOURCE_IO, 0), 8);
|
|
else
|
|
return cmos_do_probe(&pnp->dev,
|
|
pnp_get_resource(pnp, IORESOURCE_IO, 0),
|
|
pnp_irq(pnp, 0));
|
|
}
|
|
|
|
static void __exit cmos_pnp_remove(struct pnp_dev *pnp)
|
|
{
|
|
cmos_do_remove(&pnp->dev);
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
|
|
static int cmos_pnp_suspend(struct pnp_dev *pnp, pm_message_t mesg)
|
|
{
|
|
return cmos_suspend(&pnp->dev, mesg);
|
|
}
|
|
|
|
static int cmos_pnp_resume(struct pnp_dev *pnp)
|
|
{
|
|
return cmos_resume(&pnp->dev);
|
|
}
|
|
|
|
#else
|
|
#define cmos_pnp_suspend NULL
|
|
#define cmos_pnp_resume NULL
|
|
#endif
|
|
|
|
|
|
static const struct pnp_device_id rtc_ids[] = {
|
|
{ .id = "PNP0b00", },
|
|
{ .id = "PNP0b01", },
|
|
{ .id = "PNP0b02", },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(pnp, rtc_ids);
|
|
|
|
static struct pnp_driver cmos_pnp_driver = {
|
|
.name = (char *) driver_name,
|
|
.id_table = rtc_ids,
|
|
.probe = cmos_pnp_probe,
|
|
.remove = __exit_p(cmos_pnp_remove),
|
|
|
|
/* flag ensures resume() gets called, and stops syslog spam */
|
|
.flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
|
|
.suspend = cmos_pnp_suspend,
|
|
.resume = cmos_pnp_resume,
|
|
};
|
|
|
|
#endif /* CONFIG_PNP */
|
|
|
|
/*----------------------------------------------------------------*/
|
|
|
|
/* Platform setup should have set up an RTC device, when PNP is
|
|
* unavailable ... this could happen even on (older) PCs.
|
|
*/
|
|
|
|
static int __init cmos_platform_probe(struct platform_device *pdev)
|
|
{
|
|
return cmos_do_probe(&pdev->dev,
|
|
platform_get_resource(pdev, IORESOURCE_IO, 0),
|
|
platform_get_irq(pdev, 0));
|
|
}
|
|
|
|
static int __exit cmos_platform_remove(struct platform_device *pdev)
|
|
{
|
|
cmos_do_remove(&pdev->dev);
|
|
return 0;
|
|
}
|
|
|
|
static void cmos_platform_shutdown(struct platform_device *pdev)
|
|
{
|
|
cmos_do_shutdown();
|
|
}
|
|
|
|
/* work with hotplug and coldplug */
|
|
MODULE_ALIAS("platform:rtc_cmos");
|
|
|
|
static struct platform_driver cmos_platform_driver = {
|
|
.remove = __exit_p(cmos_platform_remove),
|
|
.shutdown = cmos_platform_shutdown,
|
|
.driver = {
|
|
.name = (char *) driver_name,
|
|
.suspend = cmos_suspend,
|
|
.resume = cmos_resume,
|
|
}
|
|
};
|
|
|
|
static int __init cmos_init(void)
|
|
{
|
|
#ifdef CONFIG_PNP
|
|
if (pnp_platform_devices)
|
|
return pnp_register_driver(&cmos_pnp_driver);
|
|
else
|
|
return platform_driver_probe(&cmos_platform_driver,
|
|
cmos_platform_probe);
|
|
#else
|
|
return platform_driver_probe(&cmos_platform_driver,
|
|
cmos_platform_probe);
|
|
#endif /* CONFIG_PNP */
|
|
}
|
|
module_init(cmos_init);
|
|
|
|
static void __exit cmos_exit(void)
|
|
{
|
|
#ifdef CONFIG_PNP
|
|
if (pnp_platform_devices)
|
|
pnp_unregister_driver(&cmos_pnp_driver);
|
|
else
|
|
platform_driver_unregister(&cmos_platform_driver);
|
|
#else
|
|
platform_driver_unregister(&cmos_platform_driver);
|
|
#endif /* CONFIG_PNP */
|
|
}
|
|
module_exit(cmos_exit);
|
|
|
|
|
|
MODULE_AUTHOR("David Brownell");
|
|
MODULE_DESCRIPTION("Driver for PC-style 'CMOS' RTCs");
|
|
MODULE_LICENSE("GPL");
|