@@ -684,6 +684,9 @@ config RTC_DRV_CMOS_MMIO_STRICT
select RTC_DRV_CMOS_MMIO
bool
+config RTC_DRV_CMOS_PRIV_LOCK
+ bool
+
config RTC_DRV_ALPHA
bool "Alpha PC-style CMOS"
depends on ALPHA
@@ -107,6 +107,22 @@ static inline void rtc_cmos_set_base(void __iomem *base)
static void rtc_cmos_set_base(void __iomem *base) {}
#endif
+#ifdef CONFIG_RTC_DRV_CMOS_PRIV_LOCK
+static DEFINE_SPINLOCK(rtc_private_lock);
+
+static unsigned long rtc_cmos_lock(void)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&rtc_private_lock, flags);
+ return flags;
+}
+
+static void rtc_cmos_unlock(unsigned long flags)
+{
+ spin_unlock_irqrestore(&rtc_private_lock, flags);
+}
+#endif
+
/* The RTC_INTR register may have e.g. RTC_PF set even if RTC_PIE is clear;
* always mask it against the irq enable bits in RTC_CONTROL. Bit values
* are the same: PF==PIE, AF=AIE, UF=UIE; so RTC_IRQMASK works with both.
@@ -43,6 +43,10 @@ static inline void do_cmos_write(u8 val, u8 reg)
}
#endif
+#ifdef CONFIG_RTC_DRV_CMOS_PRIV_LOCK
+static unsigned long rtc_cmos_lock(void);
+static void rtc_cmos_unlock(unsigned long flags);
+#else
static inline unsigned long rtc_cmos_lock(void)
{
unsigned long flags;
@@ -54,6 +58,7 @@ static inline void rtc_cmos_unlock(unsigned long flags)
{
spin_unlock_irqrestore(&rtc_lock, flags);
}
+#endif
/*
* Returns true if a clock update is in progress
A number of architecture happen to share a lock between the rtc-cmos driver and the core architectural code for good reasons (or at least, reasons that matter to the architecture). Other architectures don't do that, but still have to define a lock that is only used by the RTC driver. How annoying! Implement a set of driver private locking primitives, and expose a config option allowing the architecture to select it if it doesn't require to share the lock with the RTC driver. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> --- drivers/rtc/Kconfig | 3 +++ drivers/rtc/rtc-cmos.c | 16 ++++++++++++++++ include/asm-generic/rtc.h | 5 +++++ 3 files changed, 24 insertions(+)