tpm-backend: Made few interface methods optional

This allows backend implementations left optional interface methods.
For mandatory methods assertion checks added.

Took the opportunity to remove unused methods:
 - tpm_backend_get_desc()
 - TPMDriverOps->handle_startup_error

Signed-off-by: Amarnath Valluri <amarnath.valluri@intel.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger<stefanb@linux.vnet.ibm.com>
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>

1 files changed, 1 insertions, 35 deletions

diff --git a/hw/tpm/tpm_passthrough.c b/hw/tpm/tpm_passthrough.c
index 815a72ef9a..4c21e52b7c 100644
--- a/hw/tpm/tpm_passthrough.c
+++ b/hw/tpm/tpm_passthrough.c
@@ -54,7 +54,6 @@ struct TPMPassthruState {
     bool tpm_executing;
     bool tpm_op_canceled;
     int cancel_fd;
-    bool had_startup_error;
 
     TPMVersion tpm_version;
 };
@@ -227,29 +226,11 @@ static void tpm_passthrough_handle_request(TPMBackend *tb, TPMBackendCmd cmd)
     }
 }
 
-/*
- * Start the TPM (thread). If it had been started before, then terminate
- * and start it again.
- */
-static int tpm_passthrough_startup_tpm(TPMBackend *tb)
-{
-    return 0;
-}
-
 static void tpm_passthrough_reset(TPMBackend *tb)
 {
-    TPMPassthruState *tpm_pt = TPM_PASSTHROUGH(tb);
-
     DPRINTF("tpm_passthrough: CALL TO TPM_RESET!\n");
 
     tpm_passthrough_cancel_cmd(tb);
-
-    tpm_pt->had_startup_error = false;
-}
-
-static int tpm_passthrough_init(TPMBackend *tb)
-{
-    return 0;
 }
 
 static bool tpm_passthrough_get_tpm_established_flag(TPMBackend *tb)
@@ -264,13 +245,6 @@ static int tpm_passthrough_reset_tpm_established_flag(TPMBackend *tb,
     return 0;
 }
 
-static bool tpm_passthrough_get_startup_error(TPMBackend *tb)
-{
-    TPMPassthruState *tpm_pt = TPM_PASSTHROUGH(tb);
-
-    return tpm_pt->had_startup_error;
-}
-
 static size_t tpm_passthrough_realloc_buffer(TPMSizedBuffer *sb)
 {
     size_t wanted_size = 4096; /* Linux tpm.c buffer size */
@@ -309,11 +283,6 @@ static void tpm_passthrough_cancel_cmd(TPMBackend *tb)
     }
 }
 
-static const char *tpm_passthrough_create_desc(void)
-{
-    return "Passthrough TPM backend driver";
-}
-
 static TPMVersion tpm_passthrough_get_tpm_version(TPMBackend *tb)
 {
     TPMPassthruState *tpm_pt = TPM_PASSTHROUGH(tb);
@@ -453,13 +422,10 @@ static const QemuOptDesc tpm_passthrough_cmdline_opts[] = {
 static const TPMDriverOps tpm_passthrough_driver = {
     .type                     = TPM_TYPE_PASSTHROUGH,
     .opts                     = tpm_passthrough_cmdline_opts,
-    .desc                     = tpm_passthrough_create_desc,
+    .desc                     = "Passthrough TPM backend driver",
     .create                   = tpm_passthrough_create,
-    .init                     = tpm_passthrough_init,
-    .startup_tpm              = tpm_passthrough_startup_tpm,
     .realloc_buffer           = tpm_passthrough_realloc_buffer,
     .reset                    = tpm_passthrough_reset,
-    .had_startup_error        = tpm_passthrough_get_startup_error,
     .cancel_cmd               = tpm_passthrough_cancel_cmd,
     .get_tpm_established_flag = tpm_passthrough_get_tpm_established_flag,
     .reset_tpm_established_flag = tpm_passthrough_reset_tpm_established_flag,