diff options
Diffstat (limited to 'drivers/char/hw_random/intel-rng.c')
| -rw-r--r-- | drivers/char/hw_random/intel-rng.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/char/hw_random/intel-rng.c b/drivers/char/hw_random/intel-rng.c index 753f46052b87..5cc651ef75eb 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 @@ static inline u8 hwstatus_set(void __iomem *mem, 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; - - return !!(readb(mem + INTEL_RNG_STATUS) & INTEL_RNG_DATA_PRESENT); + int data, i; + + 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) |