linux/include/xen/interface/io/tpmif.h

/******************************************************************************
 * tpmif.h
 *
 * TPM I/O interface for Xen guest OSes, v2
 *
 * This file is in the public domain.
 *
 */

#ifndef __XEN_PUBLIC_IO_TPMIF_H__
#define __XEN_PUBLIC_IO_TPMIF_H__

/*
 * Xenbus state machine
 *
 * Device open:
 *   1. Both ends start in XenbusStateInitialising
 *   2. Backend transitions to InitWait (frontend does not wait on this step)
 *   3. Frontend populates ring-ref, event-channel, feature-protocol-v2
 *   4. Frontend transitions to Initialised
 *   5. Backend maps grant and event channel, verifies feature-protocol-v2
 *   6. Backend transitions to Connected
 *   7. Frontend verifies feature-protocol-v2, transitions to Connected
 *
 * Device close:
 *   1. State is changed to XenbusStateClosing
 *   2. Frontend transitions to Closed
 *   3. Backend unmaps grant and event, changes state to InitWait
 */

enum vtpm_shared_page_state { … };
/* The backend should only change state to IDLE or FINISH, while the
 * frontend should only change to SUBMIT or CANCEL. */


struct vtpm_shared_page { … };

#endif