diff options
| author | Venu Byravarasu <vbyravarasu@nvidia.com> | 2012-03-23 15:02:32 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-23 16:58:39 -0700 |
| commit | ce9f650636d310e4c8febc821b0038e9918a12db (patch) | |
| tree | 3165a949b121068c6c62b42bb9c77f20cb53f5e4 /drivers/rtc/rtc-twl.c | |
| parent | b4f0b880c8d7eb225b79dec663780b4dcdea7fbc (diff) | |
| download | lwn-ce9f650636d310e4c8febc821b0038e9918a12db.tar.gz lwn-ce9f650636d310e4c8febc821b0038e9918a12db.zip | |
drivers/rtc/rtc-twl.c: optimize IRQ bit access
As the TWL RTC driver has a cached copy of enabled RTC interrupt bits in
variable rtc_irq_bits, that can be checked before really setting or
masking any of the interrupt bits.
Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/rtc/rtc-twl.c')
| -rw-r--r-- | drivers/rtc/rtc-twl.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-twl.c b/drivers/rtc/rtc-twl.c index d43b4f6eb4e4..18dff5255670 100644 --- a/drivers/rtc/rtc-twl.c +++ b/drivers/rtc/rtc-twl.c @@ -176,6 +176,10 @@ static int set_rtc_irq_bit(unsigned char bit) unsigned char val; int ret; + /* if the bit is set, return from here */ + if (rtc_irq_bits & bit) + return 0; + val = rtc_irq_bits | bit; val &= ~BIT_RTC_INTERRUPTS_REG_EVERY_M; ret = twl_rtc_write_u8(val, REG_RTC_INTERRUPTS_REG); @@ -193,6 +197,10 @@ static int mask_rtc_irq_bit(unsigned char bit) unsigned char val; int ret; + /* if the bit is clear, return from here */ + if (!(rtc_irq_bits & bit)) + return 0; + val = rtc_irq_bits & ~bit; ret = twl_rtc_write_u8(val, REG_RTC_INTERRUPTS_REG); if (ret == 0) |