tpm: Add a constant for the minimum supported digest size
When SHA1 is used we need 20 bytes for the digest size. Add a constant so
that clients can make use of this, e.g. to allocate local buffers.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/tpm-common.h b/include/tpm-common.h
index 5f8bc6b..449ad4c 100644
--- a/include/tpm-common.h
+++ b/include/tpm-common.h
@@ -26,6 +26,8 @@
/* Max buffer size supported by our tpm */
#define TPM_DEV_BUFSIZE 1260
+#define TPM_PCR_MINIMUM_DIGEST_SIZE 20
+
/**
* enum tpm_version - The version of the TPM stack to be used
* @TPM_V1: Use TPM v1.x stack