diff --git a/drivers/misc/atsha204a-i2c.c b/drivers/misc/atsha204a-i2c.c
index aa6acf0..81ecb5b 100644
--- a/drivers/misc/atsha204a-i2c.c
+++ b/drivers/misc/atsha204a-i2c.c
@@ -21,7 +21,8 @@
 #include <linux/bitrev.h>
 #include <u-boot/crc.h>
 
-#define ATSHA204A_TWLO			60
+#define ATSHA204A_TWLO_US		60
+#define ATSHA204A_TWHI_US		2500
 #define ATSHA204A_TRANSACTION_TIMEOUT	100000
 #define ATSHA204A_TRANSACTION_RETRY	5
 #define ATSHA204A_EXECTIME		5000
@@ -109,7 +110,7 @@
 			continue;
 		}
 
-		udelay(ATSHA204A_TWLO);
+		udelay(ATSHA204A_TWLO_US + ATSHA204A_TWHI_US);
 
 		res = atsha204a_recv_resp(dev, &resp);
 		if (res) {