1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/s390/crypto/zcrypt_api.c b/drivers/s390/crypto/zcrypt_api.c
index 08f1830cbfc4..01bf1f5cf2e9 100644
--- a/drivers/s390/crypto/zcrypt_api.c
+++ b/drivers/s390/crypto/zcrypt_api.c
@@ -54,6 +54,10 @@ MODULE_DESCRIPTION("Cryptographic Coprocessor interface, " \
                    "Copyright IBM Corp. 2001, 2012");
 MODULE_LICENSE("GPL");
 
+static int zcrypt_hwrng_seed = 1;
+module_param_named(hwrng_seed, zcrypt_hwrng_seed, int, S_IRUSR|S_IRGRP);
+MODULE_PARM_DESC(hwrng_seed, "Turn on/off hwrng auto seed, default is 1 (on).");
+
 static DEFINE_SPINLOCK(zcrypt_device_lock);
 static LIST_HEAD(zcrypt_device_list);
 static int zcrypt_device_count = 0;
@@ -1373,6 +1377,7 @@ static int zcrypt_rng_data_read(struct hwrng *rng, u32 *data)
 static struct hwrng zcrypt_rng_dev = {
         .name           = "zcrypt",
         .data_read      = zcrypt_rng_data_read,
+        .quality        = 990,
 };
 
 static int zcrypt_rng_device_add(void)
@@ -1387,6 +1392,8 @@ static int zcrypt_rng_device_add(void)
                         goto out;
                 }
                 zcrypt_rng_buffer_index = 0;
+                if (!zcrypt_hwrng_seed)
+                        zcrypt_rng_dev.quality = 0;
                 rc = hwrng_register(&zcrypt_rng_dev);
                 if (rc)
                         goto out_free;