From 1bdbdaacf774f2979ed4cb0c4a4316c9e578c897 Mon Sep 17 00:00:00 2001 From: Bernhard Walle Date: Wed, 30 Jan 2008 13:33:28 +0100 Subject: [PATCH] x86, rtc: make CONFIG_HPET_EMULATE_RTC usable from modules enabled, then interrupts don't work for the rtc-cmos driver which results in RTC_AIE*, RTC_PIE* and RTC_ALM being unusable. This affects hwclock from util-linux-ng at least on i386 since that uses RTC_PIE_ON. (For x86-64, a polling method is used for unknown reasons.) This patch series now 1. export the functions from arch/x86/kernel/hpet.c that the old char/rtc driver uses to work around that problem, 2. makes it possible to compile the old rtc driver as module, while still having CONFIG_HPET_EMULATE_RTC enabled and 3. makes use of the exported functions in (1) in the new rtc-cmos driver. This patch: This patch makes the RTC emulation functions in arch/x86/kernel/hpet.c usable for kernel modules. It - exports the functions (EXPORT_SYMBOL_GPL()), - adds an interface to register the interrupt callback function instead of using only a fixed callback function and - replaces the rtc_get_rtc_time() function which depends on CONFIG_RTC with a call to get_rtc_time() which is defined in include/asm-generic/rtc.h. The only dependency to CONFIG_RTC is the call to rtc_interrupt() which is removed by the next patch. After this, there's no (code) dependency of this functions to CONFIG_RTC=y any more. Signed-off-by: Bernhard Walle Cc: Alessandro Zummo Cc: David Brownell Cc: Andi Kleen Cc: john stultz Cc: Robert Picco Signed-off-by: Andrew Morton Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/hpet.c | 47 +++++++++++++++++++++++++++++++++++++++++- include/asm-x86/hpet.h | 3 +++ 2 files changed, 49 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index 5c1702789be4..d65ced59a18f 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -107,6 +107,7 @@ int is_hpet_enabled(void) { return is_hpet_capable() && hpet_legacy_int_enabled; } +EXPORT_SYMBOL_GPL(is_hpet_enabled); /* * When the hpet driver (/dev/hpet) is enabled, we need to reserve @@ -475,6 +476,7 @@ void hpet_disable(void) */ #include #include +#include #define DEFAULT_RTC_INT_FREQ 64 #define DEFAULT_RTC_SHIFT 6 @@ -489,6 +491,38 @@ static unsigned long hpet_default_delta; static unsigned long hpet_pie_delta; static unsigned long hpet_pie_limit; +static rtc_irq_handler irq_handler; + +/* + * Registers a IRQ handler. + */ +int hpet_register_irq_handler(rtc_irq_handler handler) +{ + if (!is_hpet_enabled()) + return -ENODEV; + if (irq_handler) + return -EBUSY; + + irq_handler = handler; + + return 0; +} +EXPORT_SYMBOL_GPL(hpet_register_irq_handler); + +/* + * Deregisters the IRQ handler registered with hpet_register_irq_handler() + * and does cleanup. + */ +void hpet_unregister_irq_handler(rtc_irq_handler handler) +{ + if (!is_hpet_enabled()) + return; + + irq_handler = NULL; + hpet_rtc_flags = 0; +} +EXPORT_SYMBOL_GPL(hpet_unregister_irq_handler); + /* * Timer 1 for RTC emulation. We use one shot mode, as periodic mode * is not supported by all HPET implementations for timer 1. @@ -530,6 +564,7 @@ int hpet_rtc_timer_init(void) return 1; } +EXPORT_SYMBOL_GPL(hpet_rtc_timer_init); /* * The functions below are called from rtc driver. @@ -544,6 +579,7 @@ int hpet_mask_rtc_irq_bit(unsigned long bit_mask) hpet_rtc_flags &= ~bit_mask; return 1; } +EXPORT_SYMBOL_GPL(hpet_mask_rtc_irq_bit); int hpet_set_rtc_irq_bit(unsigned long bit_mask) { @@ -559,6 +595,7 @@ int hpet_set_rtc_irq_bit(unsigned long bit_mask) return 1; } +EXPORT_SYMBOL_GPL(hpet_set_rtc_irq_bit); int hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec) @@ -572,6 +609,7 @@ int hpet_set_alarm_time(unsigned char hrs, unsigned char min, return 1; } +EXPORT_SYMBOL_GPL(hpet_set_alarm_time); int hpet_set_periodic_freq(unsigned long freq) { @@ -590,11 +628,13 @@ int hpet_set_periodic_freq(unsigned long freq) } return 1; } +EXPORT_SYMBOL_GPL(hpet_set_periodic_freq); int hpet_rtc_dropped_irq(void) { return is_hpet_enabled(); } +EXPORT_SYMBOL_GPL(hpet_rtc_dropped_irq); static void hpet_rtc_timer_reinit(void) { @@ -638,9 +678,10 @@ irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) unsigned long rtc_int_flag = 0; hpet_rtc_timer_reinit(); + memset(&curr_time, 0, sizeof(struct rtc_time)); if (hpet_rtc_flags & (RTC_UIE | RTC_AIE)) - rtc_get_rtc_time(&curr_time); + get_rtc_time(&curr_time); if (hpet_rtc_flags & RTC_UIE && curr_time.tm_sec != hpet_prev_update_sec) { @@ -662,8 +703,12 @@ irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) if (rtc_int_flag) { rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8)); + if (irq_handler) + irq_handler(rtc_int_flag, dev_id); + rtc_interrupt(rtc_int_flag, dev_id); } return IRQ_HANDLED; } +EXPORT_SYMBOL_GPL(hpet_rtc_interrupt); #endif diff --git a/include/asm-x86/hpet.h b/include/asm-x86/hpet.h index 624f600f7161..6a9b4ac59bf7 100644 --- a/include/asm-x86/hpet.h +++ b/include/asm-x86/hpet.h @@ -69,6 +69,7 @@ extern void force_hpet_resume(void); #include +typedef irqreturn_t (*rtc_irq_handler)(int interrupt, void *cookie); extern int hpet_mask_rtc_irq_bit(unsigned long bit_mask); extern int hpet_set_rtc_irq_bit(unsigned long bit_mask); extern int hpet_set_alarm_time(unsigned char hrs, unsigned char min, @@ -77,6 +78,8 @@ extern int hpet_set_periodic_freq(unsigned long freq); extern int hpet_rtc_dropped_irq(void); extern int hpet_rtc_timer_init(void); extern irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id); +extern int hpet_register_irq_handler(rtc_irq_handler handler); +extern void hpet_unregister_irq_handler(rtc_irq_handler handler); #endif /* CONFIG_HPET_EMULATE_RTC */