When an EHCI hotplug action results in the controller disowning the
port, it will result in a hotplug action on the corresponding UHCI or
OHCI controller. Allow such hotplug actions to be carried out as part
of the same call to usb_step() or usb_register_bus(), by maintaining a
single central list of changed ports.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The USB core will currently fail to detect disconnections if a new
device has attached by the time the port is examined in
usb_hotplug().
Fix by recording the fact that a disconnection has taken place
whenever the "connection status changed" (CSC) bit is observed to be
set. (Whether the change represents a disconnection or a
reconnection, it indicates that the port has experienced some time of
being disconnected.)
Note that the time at which a disconnection can be detected varies by
hub type. In particular: root hubs can observe the CSC bit when
polling, and so will record the disconnection before calling
usb_port_changed(), but USB hubs read the port status (and hence the
CSC bit) only during the call to hub_speed(), long after the call to
usb_port_changed().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The USB API currently assumes that host controllers will have
immediate data buffer space available in which to store the setup
packet. This is true for xHCI, partially true for EHCI (which happens
to have 12 bytes of padding in each transfer descriptor due to
alignment requirements), and not true at all for UHCI.
Include the setup packet within the I/O buffer passed to the host
controller's message() method, thereby eliminating the requirement for
host controllers to provide immediate data buffers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
xHCI provides a somewhat convoluted mechanism for specifying details
of a transaction translator. Hubs must be marked as such in the
device slot context. The only opportunity to do so is as part of a
Configure Endpoint command, which can be executed only when opening
the hub's interrupt endpoint.
We add a mechanism for host controllers to intercept the opening of
hub devices, providing xHCI with an opportunity to update the internal
device slot structure for the corresponding USB device to indicate
that the device is a hub. We then include the hub-specific details in
the input context whenever any Configure Endpoint command is issued.
When a device is opened, we record the device slot and port for its
transaction translator (if any), and supply these as part of the
Address Device command.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The current endpoint reset logic defers the reset until the caller
attempts to enqueue a new transfer to that endpoint. This is
insufficient when dealing with endpoints behind a transaction
translator, since the transaction translator is a resource shared
between multiple endpoints.
We cannot reset the endpoint as part of the completion handling, since
that would introduce recursive calls to usb_poll(). Instead, we
add the endpoint to a list of halted endpoints, and perform the reset
on the next call to usb_step().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Several of the USB timeouts were chosen on the principle of "pick an
arbitrary but ridiculously large value, just to be safe". It turns
out that some of the timeouts permitted by the USB specification are
even larger: for example, control transactions are allowed to take up
to five seconds to complete.
Fix up these USB timeout values to match those found in the USB2
specification.
Debugged-by: Robin Smidsrød <robin@smidsrod.no>
Tested-by: Robin Smidsrød <robin@smidsrod.no>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
At some point in the past few years, binutils became more aggressive
at removing unused symbols. To function as a symbol requirement, a
relocation record must now be in a section marked with @progbits and
must not be in a section which gets discarded during the link (either
via --gc-sections or via /DISCARD/).
Update REQUIRE_SYMBOL() to generate relocation records meeting these
criteria. To minimise the impact upon the final binary size, we use
existing symbols (specified via the REQUIRING_SYMBOL() macro) as the
relocation targets where possible. We use R_386_NONE or R_X86_64_NONE
relocation types to prevent any actual unwanted relocation taking
place. Where no suitable symbol exists for REQUIRING_SYMBOL() (such
as in config.c), the macro PROVIDE_REQUIRING_SYMBOL() can be used to
generate a one-byte-long symbol to act as the relocation target.
If there are versions of binutils for which this approach fails, then
the fallback will probably involve killing off REQUEST_SYMBOL(),
redefining REQUIRE_SYMBOL() to use the current definition of
REQUEST_SYMBOL(), and postprocessing the linked ELF file with
something along the lines of "nm -u | wc -l" to check that there are
no undefined symbols remaining.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide a generic framework for allocating, refilling, and optionally
recycling I/O buffers used by bulk IN and interrupt endpoints.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Commit a60f2dd ("[usb] Try multiple USB device configurations")
changed the behaviour of register_usb() such that if no drivers are
found then the device will be closed and the memory used will be
freed.
If a port status change subsequently occurs while the device is still
physically attached, then usb_hotplug() will see this as a new device
having been attached, since there is no device recorded as being
currently attached to the port. This can lead to spurious hotplug
events (or even endless loops of hotplug events, if the process of
opening and closing the device happens to generate a port status
change).
Fix by using a separate flag to indicate that a device is physically
attached (even if we have no corresponding struct usb_device).
Reported-by: Dan Ellis <Dan.Ellis@displaylink.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some USB endpoints require that a short packet be used to terminate
transfers, since they have no other way to determine message
boundaries. If the message length happens to be an exact multiple of
the USB packet size, then this requires the use of an additional
zero-length packet.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
USB Communications Device Class devices may use a union functional
descriptor to group several interfaces into a function.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Iterate over a USB device's available configurations until we find one
for which we have working drivers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown