2007-12-20 15:49:38

by Bernhard Walle

[permalink] [raw]
Subject: [patch 2/3] Use the IRQ callback interface in (old) RTC driver

That function uses the new registration callback mechanism which was added in
the previous patch in the old RTC driver. It also removes the direct
rtc_interrupt() call from arch/x86/kernel/hpetc.c so that there's finally
no (code) dependency to CONFIG_RTC in arch/x86/kernel/hpet.c.

Because of this, it's possible to compile the drivers/char/rtc.ko driver
as module and still use the HPET emulation functionality. This is also
expressed in Kconfig.


Signed-off-by: Bernhard Walle <[email protected]>

---
arch/x86/Kconfig | 2 +-
arch/x86/kernel/hpet.c | 2 --
drivers/char/rtc.c | 15 ++++++++++++++-
3 files changed, 15 insertions(+), 4 deletions(-)

--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -405,7 +405,7 @@ config HPET_TIMER

config HPET_EMULATE_RTC
def_bool y
- depends on HPET_TIMER && RTC=y
+ depends on HPET_TIMER && (RTC=y || RTC=m)

# Mark as embedded because too many people got it wrong.
# The code disables itself when not needed.
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -708,8 +708,6 @@ irqreturn_t hpet_rtc_interrupt(int irq,
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;
}
--- a/drivers/char/rtc.c
+++ b/drivers/char/rtc.c
@@ -110,6 +110,8 @@ static int rtc_has_irq = 1;
#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)
{
@@ -1027,7 +1029,15 @@ no_irq:

#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;
}
@@ -1050,6 +1060,7 @@ no_irq:
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();
@@ -1141,8 +1152,10 @@ static void __exit rtc_exit(void)
#else
rtc_release_region();
#ifdef RTC_IRQ
- if (rtc_has_irq)
+ if (rtc_has_irq) {
free_irq(RTC_IRQ, NULL);
+ hpet_unregister_irq_handler(hpet_rtc_interrupt);
+ }
#endif
#endif /* CONFIG_SPARC32 */
}