mm: thp: set the accessed flag for old pages on access fault

[pandora-kernel.git] / drivers / rtc / rtc-wm831x.c

diff --git a/drivers/rtc/rtc-wm831x.c b/drivers/rtc/rtc-wm831x.c
index bdc909b..f3c2110 100644 (file)
--- a/drivers/rtc/rtc-wm831x.c
+++ b/drivers/rtc/rtc-wm831x.c
@@ -24,7 +24,7 @@
 #include <linux/mfd/wm831x/core.h>
 #include <linux/delay.h>
 #include <linux/platform_device.h>
-
+#include <linux/random.h>
 
 /*
  * R16416 (0x4020) - RTC Write Counter
@@ -96,6 +96,26 @@ struct wm831x_rtc {
        unsigned int alarm_enabled:1;
 };
 
+static void wm831x_rtc_add_randomness(struct wm831x *wm831x)
+{
+       int ret;
+       u16 reg;
+
+       /*
+        * The write counter contains a pseudo-random number which is
+        * regenerated every time we set the RTC so it should be a
+        * useful per-system source of entropy.
+        */
+       ret = wm831x_reg_read(wm831x, WM831X_RTC_WRITE_COUNTER);
+       if (ret >= 0) {
+               reg = ret;
+               add_device_randomness(&reg, sizeof(reg));
+       } else {
+               dev_warn(wm831x->dev, "Failed to read RTC write counter: %d\n",
+                        ret);
+       }
+}
+
 /*
  * Read current time and date in RTC
  */
@@ -449,6 +469,8 @@ static int wm831x_rtc_probe(struct platform_device *pdev)
                        alm_irq, ret);
        }
 
+       wm831x_rtc_add_randomness(wm831x);
+
        return 0;
 
 err: