[HWRNG]: move status polling loop to data_present callbacks

Handle waiting for new random within the drivers themselves, this allows to
use better suited timeouts for the individual rngs.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 11 insertions, 3 deletions

diff --git a/drivers/char/hw_random/pasemi-rng.c b/drivers/char/hw_random/pasemi-rng.c
index fa6040b6c8f2..621adf25e580 100644
--- a/drivers/char/hw_random/pasemi-rng.c
+++ b/drivers/char/hw_random/pasemi-rng.c
@@ -23,6 +23,7 @@
 #include <linux/kernel.h>
 #include <linux/platform_device.h>
 #include <linux/hw_random.h>
+#include <linux/delay.h>
 #include <asm/of_platform.h>
 #include <asm/io.h>
 
@@ -44,9 +45,16 @@
 static int pasemi_rng_data_present(struct hwrng *rng)
 {
         void __iomem *rng_regs = (void __iomem *)rng->priv;
-
-        return (in_le32(rng_regs + SDCRNG_CTL_REG)
-                & SDCRNG_CTL_FVLD_M) ? 1 : 0;
+        int data, i;
+
+        for (i = 0; i < 20; i++) {
+                data = (in_le32(rng_regs + SDCRNG_CTL_REG)
+                        & SDCRNG_CTL_FVLD_M) ? 1 : 0;
+                if (data || !wait)
+                        break;
+                udelay(10);
+        }
+        return data;
 }
 
 static int pasemi_rng_data_read(struct hwrng *rng, u32 *data)