diff options
Diffstat (limited to 'drivers/crypto/qcom-rng.c')
| -rw-r--r-- | drivers/crypto/qcom-rng.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c index 99ba8d51d102..11f30fd48c14 100644 --- a/drivers/crypto/qcom-rng.c +++ b/drivers/crypto/qcom-rng.c @@ -8,6 +8,7 @@ #include <linux/clk.h> #include <linux/crypto.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> @@ -43,16 +44,19 @@ static int qcom_rng_read(struct qcom_rng *rng, u8 *data, unsigned int max) { unsigned int currsize = 0; u32 val; + int ret; /* read random data from hardware */ do { - val = readl_relaxed(rng->base + PRNG_STATUS); - if (!(val & PRNG_STATUS_DATA_AVAIL)) - break; + ret = readl_poll_timeout(rng->base + PRNG_STATUS, val, + val & PRNG_STATUS_DATA_AVAIL, + 200, 10000); + if (ret) + return ret; val = readl_relaxed(rng->base + PRNG_DATA_OUT); if (!val) - break; + return -EINVAL; if ((max - currsize) >= WORD_SZ) { memcpy(data, &val, WORD_SZ); @@ -61,11 +65,10 @@ static int qcom_rng_read(struct qcom_rng *rng, u8 *data, unsigned int max) } else { /* copy only remaining bytes */ memcpy(data, &val, max - currsize); - break; } } while (currsize < max); - return currsize; + return 0; } static int qcom_rng_generate(struct crypto_rng *tfm, @@ -87,7 +90,7 @@ static int qcom_rng_generate(struct crypto_rng *tfm, mutex_unlock(&rng->lock); clk_disable_unprepare(rng->clk); - return 0; + return ret; } static int qcom_rng_seed(struct crypto_rng *tfm, const u8 *seed, |