Add a separate tracepoint to log how register values change in response
to a mmio write.  Especially useful for registers which have read-only
or clear-on-write bits in them.

No change in behavior.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

Trace usb port operations (attach, detach, reset),
drop a few obsolete DPRINTF's.

No change in behavior.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

Add functions to get and set the current state of the state machine,
add tracepoints there to trace state transitions.  Add support for
traceing the queue heads and transfer descriptors as we look at them.

Drop a few DPRINTFs and all DPRINTF_ST lines, they are obsolete now.

No change in behavior.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

This patch starts adding trace support to ehci.  It traces
updates of the status register (USBSTS), mmio access and
controller reset.

It also adds functions to set and clear status register bits
and puts them in use everywhere.

Some DPRINTF's are dropped in favor of the new tracepoints.

No change in behavior.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

This patch finally merges the EHCI host adapter aka USB 2.0 support.

Based on the ehci bits collected @ git://git.kiszka.org/qemu.git ehci

EHCI has a long out-of-tree history.  Project was started by Mark
Burkley, with contributions by Niels de Vos.  David S. Ahern continued
working on it.  Kevin Wolf, Jan Kiszka and Vincent Palatin contributed
bugfixes.

/me (Gerd Hoffmann) picked it up where it left off, prepared the code
for merge, fixed a few bugs and added basic user docs.

Cc: David S. Ahern <daahern@cisco.com>
Cc: Jan Kiszka <jan.kiszka@web.de>
Cc: Kevin Wolf <mail@kevin-wolf.de>
Cc: Vincent Palatin <vincent.palatin_qemu@m4x.org>
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>