diff options
Diffstat (limited to 'drivers/char/hw_random/mxc-rnga.c')
| -rw-r--r-- | drivers/char/hw_random/mxc-rnga.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/drivers/char/hw_random/mxc-rnga.c b/drivers/char/hw_random/mxc-rnga.c index 187c6be80f43..85074de5042e 100644 --- a/drivers/char/hw_random/mxc-rnga.c +++ b/drivers/char/hw_random/mxc-rnga.c @@ -24,6 +24,7 @@ #include <linux/ioport.h> #include <linux/platform_device.h> #include <linux/hw_random.h> +#include <linux/delay.h> #include <linux/io.h> /* RNGA Registers */ @@ -60,16 +61,20 @@ static struct platform_device *rng_dev; -static int mxc_rnga_data_present(struct hwrng *rng) +static int mxc_rnga_data_present(struct hwrng *rng, int wait) { - int level; void __iomem *rng_base = (void __iomem *)rng->priv; - - /* how many random numbers is in FIFO? [0-16] */ - level = ((__raw_readl(rng_base + RNGA_STATUS) & - RNGA_STATUS_LEVEL_MASK) >> 8); - - return level > 0 ? 1 : 0; + int i; + + for (i = 0; i < 20; i++) { + /* how many random numbers are in FIFO? [0-16] */ + int level = (__raw_readl(rng_base + RNGA_STATUS) & + RNGA_STATUS_LEVEL_MASK) >> 8; + if (level || !wait) + return !!level; + udelay(10); + } + return 0; } static int mxc_rnga_data_read(struct hwrng *rng, u32 * data) |