drivers/rtc/rtc-sirfsoc.c: replace local_irq_disable by spin_lock_irq for SMP safety

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Cc: hao liu <hao.liu@csr.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>

1 files changed, 19 insertions, 8 deletions

diff --git a/drivers/rtc/rtc-sirfsoc.c b/drivers/rtc/rtc-sirfsoc.c
index a9ea7d181380..d2ac6688e5c7 100644
--- a/drivers/rtc/rtc-sirfsoc.c
+++ b/drivers/rtc/rtc-sirfsoc.c
@@ -47,6 +47,7 @@ struct sirfsoc_rtc_drv {
         unsigned                irq_wake;
         /* Overflow for every 8 years extra time */
         u32                     overflow_rtc;
+        spinlock_t              lock;
 #ifdef CONFIG_PM
         u32             saved_counter;
         u32             saved_overflow_rtc;
@@ -61,7 +62,7 @@ static int sirfsoc_rtc_read_alarm(struct device *dev,
 
         rtcdrv = dev_get_drvdata(dev);
 
-        local_irq_disable();
+        spin_lock_irq(&rtcdrv->lock);
 
         rtc_count = sirfsoc_rtc_iobrg_readl(rtcdrv->rtc_base + RTC_CN);
 
@@ -84,7 +85,8 @@ static int sirfsoc_rtc_read_alarm(struct device *dev,
         if (sirfsoc_rtc_iobrg_readl(
                         rtcdrv->rtc_base + RTC_STATUS) & SIRFSOC_RTC_AL0E)
                 alrm->enabled = 1;
-        local_irq_enable();
+
+        spin_unlock_irq(&rtcdrv->lock);
 
         return 0;
 }
@@ -99,7 +101,7 @@ static int sirfsoc_rtc_set_alarm(struct device *dev,
         if (alrm->enabled) {
                 rtc_tm_to_time(&(alrm->time), &rtc_alarm);
 
-                local_irq_disable();
+                spin_lock_irq(&rtcdrv->lock);
 
                 rtc_status_reg = sirfsoc_rtc_iobrg_readl(
                                 rtcdrv->rtc_base + RTC_STATUS);
@@ -123,14 +125,15 @@ static int sirfsoc_rtc_set_alarm(struct device *dev,
                 rtc_status_reg |= SIRFSOC_RTC_AL0E;
                 sirfsoc_rtc_iobrg_writel(
                         rtc_status_reg, rtcdrv->rtc_base + RTC_STATUS);
-                local_irq_enable();
+
+                spin_unlock_irq(&rtcdrv->lock);
         } else {
                 /*
                  * if this function was called with enabled=0
                  * then it could mean that the application is
                  * trying to cancel an ongoing alarm
                  */
-                local_irq_disable();
+                spin_lock_irq(&rtcdrv->lock);
 
                 rtc_status_reg = sirfsoc_rtc_iobrg_readl(
                                 rtcdrv->rtc_base + RTC_STATUS);
@@ -146,7 +149,7 @@ static int sirfsoc_rtc_set_alarm(struct device *dev,
                                         rtcdrv->rtc_base + RTC_STATUS);
                 }
 
-                local_irq_enable();
+                spin_unlock_irq(&rtcdrv->lock);
         }
 
         return 0;
@@ -217,7 +220,7 @@ static int sirfsoc_rtc_alarm_irq_enable(struct device *dev,
 
         rtcdrv = dev_get_drvdata(dev);
 
-        local_irq_disable();
+        spin_lock_irq(&rtcdrv->lock);
 
         rtc_status_reg = sirfsoc_rtc_iobrg_readl(
                                 rtcdrv->rtc_base + RTC_STATUS);
@@ -227,7 +230,8 @@ static int sirfsoc_rtc_alarm_irq_enable(struct device *dev,
                 rtc_status_reg &= ~SIRFSOC_RTC_AL0E;
 
         sirfsoc_rtc_iobrg_writel(rtc_status_reg, rtcdrv->rtc_base + RTC_STATUS);
-        local_irq_enable();
+
+        spin_unlock_irq(&rtcdrv->lock);
 
         return 0;
 
@@ -248,6 +252,8 @@ static irqreturn_t sirfsoc_rtc_irq_handler(int irq, void *pdata)
         unsigned long rtc_status_reg = 0x0;
         unsigned long events = 0x0;
 
+        spin_lock(&rtcdrv->lock);
+
         rtc_status_reg = sirfsoc_rtc_iobrg_readl(rtcdrv->rtc_base + RTC_STATUS);
         /* this bit will be set ONLY if an alarm was active
          * and it expired NOW
@@ -265,6 +271,9 @@ static irqreturn_t sirfsoc_rtc_irq_handler(int irq, void *pdata)
                 rtc_status_reg &= ~(SIRFSOC_RTC_AL0E);
         }
         sirfsoc_rtc_iobrg_writel(rtc_status_reg, rtcdrv->rtc_base + RTC_STATUS);
+
+        spin_unlock(&rtcdrv->lock);
+
         /* this should wake up any apps polling/waiting on the read
          * after setting the alarm
          */
@@ -292,6 +301,8 @@ static int sirfsoc_rtc_probe(struct platform_device *pdev)
         if (rtcdrv == NULL)
                 return -ENOMEM;
 
+        spin_lock_init(&rtcdrv->lock);
+
         err = of_property_read_u32(np, "reg", &rtcdrv->rtc_base);
         if (err) {
                 dev_err(&pdev->dev, "unable to find base address of rtc node in dtb\n");