ASoC: cros_ec_codec: use sha256() instead of open coding

Now that there's a function that calculates the SHA-256 digest of a
buffer in one step, use it instead of sha256_init() + sha256_update() +
sha256_final().

Also simplify the code by inlining calculate_sha256() into its caller
and switching a debug log statement to use %*phN instead of bin2hex().
Acked-by: Tzung-Bi Shih <tzungbi@google.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Cc: alsa-devel@alsa-project.org
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Cheng-Yi Chiang <cychiang@chromium.org>
Cc: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

sound/soc/codecs/cros_ec_codec.c

@@ -103,28 +103,6 @@ static int send_ec_host_command(struct cros_ec_device *ec_dev, uint32_t cmd,
 	return ret;
 }
 
-static int calculate_sha256(struct cros_ec_codec_priv *priv,
-			    uint8_t *buf, uint32_t size, uint8_t *digest)
-{
-	struct sha256_state sctx;
-
-	sha256_init(&sctx);
-	sha256_update(&sctx, buf, size);
-	sha256_final(&sctx, digest);
-
-#ifdef DEBUG
-	{
-		char digest_str[65];
-
-		bin2hex(digest_str, digest, 32);
-		digest_str[64] = 0;
-		dev_dbg(priv->dev, "hash=%s\n", digest_str);
-	}
-#endif
-
-	return 0;
-}
-
 static int dmic_get_gain(struct snd_kcontrol *kcontrol,
 			 struct snd_ctl_elem_value *ucontrol)
 {
@@ -782,9 +760,8 @@ static int wov_hotword_model_put(struct snd_kcontrol *kcontrol,
 	if (IS_ERR(buf))
 		return PTR_ERR(buf);
 
-	ret = calculate_sha256(priv, buf, size, digest);
-	if (ret)
-		goto leave;
+	sha256(buf, size, digest);
+	dev_dbg(priv->dev, "hash=%*phN\n", SHA256_DIGEST_SIZE, digest);
 
 	p.cmd = EC_CODEC_WOV_GET_LANG;
 	ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_WOV,