[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>
diff --git a/drivers/char/hw_random/intel-rng.c b/drivers/char/hw_random/intel-rng.c
index 753f460..5cc651e 100644
--- a/drivers/char/hw_random/intel-rng.c
+++ b/drivers/char/hw_random/intel-rng.c
@@ -29,6 +29,7 @@
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/stop_machine.h>
+#include <linux/delay.h>
#include <asm/io.h>
@@ -162,11 +163,19 @@
return hwstatus_get(mem);
}
-static int intel_rng_data_present(struct hwrng *rng)
+static int intel_rng_data_present(struct hwrng *rng, int wait)
{
void __iomem *mem = (void __iomem *)rng->priv;
+ int data, i;
- return !!(readb(mem + INTEL_RNG_STATUS) & INTEL_RNG_DATA_PRESENT);
+ for (i = 0; i < 20; i++) {
+ data = !!(readb(mem + INTEL_RNG_STATUS) &
+ INTEL_RNG_DATA_PRESENT);
+ if (data || !wait)
+ break;
+ udelay(10);
+ }
+ return data;
}
static int intel_rng_data_read(struct hwrng *rng, u32 *data)