Hi, The Qualcomm QCE driver implementation defines: .flags = QCE_ALG_AES | QCE_MODE_XTS, .name = "xts(aes)", .drv_name = "xts-aes-qce", .blocksize = AES_BLOCK_SIZE, .ivsize = AES_BLOCK_SIZE, .min_keysize = AES_MIN_KEY_SIZE, .max_keysize = AES_MAX_KEY_SIZE, and alg->cra_ablkcipher.min_keysize = def->min_keysize; alg->cra_ablkcipher.max_keysize = def->max_keysize; alg->cra_ablkcipher.setkey = qce_ablkcipher_setkey; Thus, this driver has the limits of 128 to 256 bits for the key. Furthermore, the common setkey function is used. May I ask how the key for AES XTS is supposed to be handled here considering that the kernel crypto API expects that the AES key and the tweak key is set via one setkey call. I.e. the setkey should expect 256 through 512 bits. Thanks. Ciao Stephan