Allow scripts to read basic information from USB device descriptors
via the settings mechanism. For example:
echo USB vendor ID: ${usb/${busloc}.8.2}
echo USB device ID: ${usb/${busloc}.10.2}
echo USB manufacturer name: ${usb/${busloc}.14.0}
The general syntax is
usb/<bus:dev>.<offset>.<length>
where bus:dev is the USB bus:device address (as obtained via the
"usbscan" command, or from e.g. ${net0/busloc} for a USB network
device), and <offset> and <length> select the required portion of the
USB device descriptor.
Following the usage of SMBIOS settings tags, a <length> of zero may be
used to indicate that the byte at <offset> contains a USB string
descriptor index, and an <offset> of zero may be used to indicate that
the <length> contains a literal USB string descriptor index.
Since the byte at offset zero can never contain a string index, and a
literal string index can never be zero, the combination of both
<length> and <offset> being zero may be used to indicate that the
entire device descriptor is to be read as a raw hex dump.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Implement a "usbscan" command as a direct analogy of the existing
"pciscan" command, allowing scripts to iterate over all detected USB
devices.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Commit 87e39a9c9 ("[efi] Split efi_usb_path() out to a separate
function") unintentionally introduced an undefined symbol reference
from efi_path.o to usb_depth(), causing the USB subsystem to become a
dependency of all EFI builds.
Fix by converting usb_depth() to a static inline function.
Reported-by: Pico Mitchell <pico@randomapplications.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
For USB mass storage devices, we do not want to submit more bulk IN
packets than are required for the inbound data, since this will waste
memory.
Allow an upper limit to be specified on each refill attempt. The
endpoint will be refilled to the lower of this limit or the limit
specified by usb_refill_init().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Closing and reopening a USB endpoint will clear any halt status
recorded by the host controller, but may leave the endpoint halted at
the device. This will cause the first packet submitted to the
reopened endpoint to be lost, before the automatic stall recovery
mechanism detects the halt and resets the endpoint.
This is relatively harmless for USB network or HID devices, since the
wire protocols will recover gracefully from dropped packets. Some
protocols (e.g. for USB mass storage devices) assume zero packet loss
and so would be adversely affected.
Fix by allowing any device endpoint halt status to be cleared on a
freshly opened endpoint.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The current error handling mechanism defers the endpoint reset until
the next use of the endpoint, on the basis that errors are detected
during completions and completion handling should not recursively call
usb_poll().
In the case of usb_control(), we are already at the level that calls
usb_poll() and can therefore safely perform the endpoint reset
immediately. This has no impact on functionality, but does make
debugging traces easier to read since the reset will appear
immediately after the causative error.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
A failure in device registration (e.g. due to a device with malformed
descriptors) will currently result in the port being disabled as part
of the error path. This in turn causes the hardware to detect the
device as newly connected, leading to an endless loop of failed device
registrations.
Fix by leaving the port enabled in the case of a registration failure.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Resetting the host endpoint may immediately restart any pending
transfers for that endpoint. If the device endpoint halt has not yet
been cleared, then this will probably result in a second failed
transfer.
This second failure may be detected within usb_endpoint_reset() while
waiting for usb_clear_feature() to complete. The endpoint will
subsequently be removed from the list of halted endpoints, causing the
second failure to be effectively ignored and leaving the host endpoint
in a permanently halted state.
Fix by deferring the host endpoint reset until after the device
endpoint is ready to accept new transfers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We currently use a zero language ID to retrieve strings such as the
ECM/NCM MAC address. This works on most hardware devices, but is
known to fail on some software emulated CDC-NCM devices.
Fix by using the first supported language ID, falling back to English
(0x0409) if any error occurs when fetching the list of supported
languages. This matches the behaviour of the Linux kernel.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Record the speed of a USB device based on the port's speed at the time
that the device was enabled. This allows us to remember the device's
speed even after the device has been disconnected (and so the port's
current speed has changed).
In particular, this allows us to correctly identify the transaction
translator for a low-speed or full-speed device after the device has
been disconnected.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The usb_message() and usb_stream() functions currently check for
port->speed==USB_SPEED_NONE to determine whether or not a device has
been unplugged. This test will give a false negative result if a new
device has been plugged in before the hotplug mechanism has finished
handling the removal of the old device.
Fix by checking instead the port->disconnected flag, which is now
cleared only after completing the removal of the old device.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Make the class ID a property of the USB driver (rather than a property
of the USB device ID), and allow USB drivers to specify a wildcard ID
for any of the three component IDs (class, subclass, or protocol).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Generate a score for each possible USB device configuration based on
the available driver support, and select the configuration with the
highest score. This will allow us to prefer ECM over RNDIS (for
devices which support both) and will allow us to meaningfully select a
configuration even when we have drivers available for all functions
(e.g. when exposing unused functions via EFI_USB_IO_PROTOCOL).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The decision on whether or not a zero-length packet needs to be
transmitted is independent of the host controller and belongs in the
USB core.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The recorded disconnections (in port->disconnected) will currently be
left uncleared if usb_attached() returns an error (e.g. because there
are no drivers for a particular USB device). This is incorrect
behaviour: the disconnection has been handled and the record should be
cleared until the next physical disconnection is detected (via the CSC
bit).
The problem is masked for EHCI, UHCI, and USB hubs, since these will
report a changed port (via usb_port_changed()) only when the
underlying hardware reports a change. xHCI will call
usb_port_changed() in response to any port status event, at which
point the stale value of port->disconnected will be erroneously acted
upon. This can lead to an endless loop of repeatedly enumerating the
same device when a driverless device is attached to an xHCI root hub
port.
Fix by unconditionally clearing port->disconnected in usb_hotplugged().
Reported-by: Robin Smidsrød <robin@smidsrod.no>
Tested-by: Robin Smidsrød <robin@smidsrod.no>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The action of registering a new hub can itself happen in only two
ways: either a new USB hub has been created (in which case we are
already inside a call to usb_hotplug()), or a new root hub has been
created.
In the former case, we do not need to issue a further call to
usb_hotplug(), since the hub's ports will all be marked as changed and
so will be handled after the return from register_usb_hub() anyway.
Calling usb_hotplug() within register_usb_hub() leads to a confusing
order of events, such as:
- root hub port 1 detects a change
- root hub port 2 detects a change
- usb_hotplug() is called
- root hub port 1 finds a USB hub
- usb_hotplug() is called
- this inner call to usb_hotplug() handles root hub port 2
Fix by calling usb_hotplug() only from usb_step() and from
register_usb_bus(). This avoids recursive calls to usb_hotplug() and
ensures that devices are enumerated in the order of detection.
Tested-by: Robin Smidsrød <robin@smidsrod.no>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
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