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path: root/drivers/staging/greybus/connection.c
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2016-01-21greybus: connection: set request handlers at creationGravatar Johan Hovold 1-28/+66
Set the connection request handler at creation rather than when enabling the connection. This is possible now that connections are created by the drivers that use them rather than by core at manifest parsing time. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-21greybus: connection: return error-valued pointer on creation errorsGravatar Johan Hovold 1-7/+15
Return an ERR_PTR on errors when creating connections. This allows driver probe to fail with a more informative error message as not all connection creation errors are due to memory exhaustion. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-21greybus: connection: rename connection-create interfaceGravatar Johan Hovold 1-7/+7
Drop the _dynamic suffix from the exported interface that drivers use to create connections. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-21greybus: connection: simplify connection-creation interfaceGravatar Johan Hovold 1-3/+3
Simplify the exported generic interface for creating dynamic connections. Since all driver connections will have a bundle we can drop the redundant interface parameter. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-21greybus: connection: drop the legacy protocol-id parameterGravatar Johan Hovold 1-10/+5
The protocol-id parameter is only used by the legacy driver so remove it from the generic interface and move it to the legacy driver until it can be removed completely. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-21greybus: connection: add helper to create control connectionsGravatar Johan Hovold 1-0/+6
Add dedicated helper to create control connections. This will allow us to simplify the generic (dynamic) interface. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-21greybus: connection: drop protocol parameter from static interfaceGravatar Johan Hovold 1-4/+2
Drop legacy protocol parameter from static connection interface. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-21greybus: core: defer connection creation to driver probeGravatar Johan Hovold 1-0/+2
Defer connection creation to bundle driver probe instead of creating them when initialising the interface and parsing the manifest. Store copies of the CPorts descriptors in the bundle for the drivers to use, and update the legacy driver. This is needed for drivers that need more control over host-device resource management, for example, when a protocol needs to use a dedicated host CPort for traffic offloading (e.g. camera data). This also avoids allocating host CPorts for bundles that are not bound to a driver or for remote CPorts that a driver does not need. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: make cport lookup thread-safeGravatar Johan Hovold 1-12/+6
Use the gb_connection_mutex when making sure a remote CPort is available. This is needed when moving to driver-managed connections that can be created and destroyed at any time. Also check for duplicate bundle-less connections. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: serialise connection creationGravatar Johan Hovold 1-1/+16
Serialise connection creation against concurrent creation and destruction using a global mutex. This is needed to prevent two drivers from attempting to create a connection to the same interface CPort and to cope with a racing connection destroy when moving to driver managed connections. Note that the locking can not (easily) be made more fine-grained as not all connections have an interface, but these are not hot paths anyway. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: fix lookup raceGravatar Johan Hovold 1-2/+21
Fix longstanding race that could lead to a connection being destroyed while processing an incoming message due to missing reference counting when looking up the connection. Add helpers to manipulate the connection kref. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: drop the connection_mutexGravatar Johan Hovold 1-5/+1
Drop the useless connection_mutex that did not, and can not be used to prevent connection lookup races in atomic context and therefore serves no purpose. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: destroy workqueue at unregisterGravatar Johan Hovold 1-4/+4
Destroy the work queue when the connection is destroyed/deregistered instead of when the last reference is dropped. The work queue is not needed once the connection has been deregistered, and no operations will ever be added to it again (handled by checking connection->state) even if the connection object may not be deallocated until the final reference is dropped. The work-queue name is set based on the host-device name and host-device cport id, something which guarantees a unique name. This would no longer be true if the work queue was not destroyed at connection deregistration as a new connection could then be created for that very same host cport. This is not necessarily a problem unless some work queue features are used that require unique work-queue names, but let's try to be well behaved. Also update an obsolete comment and make explicit that a connection must be disabled before being destroyed. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: remove WARN_ON from destroyGravatar Johan Hovold 1-1/+1
Remove WARN_ON from connection destroy testing for a NULL-connection when destroying a connection. This will allow for simpler driver code when releasing driver-managed connections. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: remove broken protocol-version handlingGravatar Johan Hovold 1-4/+0
Remove the broken legacy protocol-version handling from core and move it to the legacy driver instead. Note that version handling has always been broken as legacy protocols were looked up and bound to connections before the connections were enabled and version negotiation could take place (over that very connection). Document that in the legacy driver as well. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: move legacy-protocol handling to legacy driverGravatar Johan Hovold 1-107/+0
Move legacy protocol and connection handling to the legacy driver. Rename the former global functions using a common legacy_ prefix. Note that all legacy protocols suffer from a connection initialisation race in that the protocol-specific initialisation, which includes allocation of protocol-specific state containers, can not happen until *after* the connection has been enabled. This is a major flaw in the original design that we can now finally address by converting the legacy protocol drivers into proper bundle (class) drivers. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: svc: drop legacy-protocol dependencyGravatar Johan Hovold 1-6/+1
Drop dependency on the legacy protocol abstraction. Remove the now unused and last legacy-protocol flag GB_PROTOCOL_SKIP_VERSION along with the protocol-flag feature. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: remove skip-connected legacy protocol flagsGravatar Johan Hovold 1-6/+10
Remove the legacy protocol flags that were used to suppress the connected and disconnected events. Instead send the connected and disconnected event for all bundle connections and explicitly exclude static connections and control connections. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: add helper to disable incoming operationsGravatar Johan Hovold 1-0/+54
Add helper to disable and flush incoming operations. This is intended to be used by core to flush any incoming requests before calling driver disconnect, but could potentially later be exported for driver use as well. Note that we currently flush all incoming operation and allow the request handlers to run, but cancel any responses sent. This may need to be refined later. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: add unidirectional enabled stateGravatar Johan Hovold 1-1/+18
Add a new connection state ENABLED_TX in which only outgoing operations are allowed. This allows drivers to query the device during probe before allocating their state containers without having to worry about racing incoming requests. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: make connection enable/disable thread safeGravatar Johan Hovold 1-2/+18
Add connection mutex to protect connection enabling and disabling. This is needed to eventually allow drivers to manage the state of their connections during operation (i.e. post probe and pre disconnect). Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: disable operations on enable errorsGravatar Johan Hovold 1-0/+1
Make sure to cancel all (incoming) operations when failing to enable a connection. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: clean up operation cancellation on disableGravatar Johan Hovold 1-31/+28
Move helper to cancel active operations above gb_connection_enable and simplify locking. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: always cancel operations on connection disableGravatar Johan Hovold 1-9/+8
Always cancel all operations on connection disable and remove the now unused DESTROYING state. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: add per-connection request handlersGravatar Johan Hovold 1-2/+17
Add a connection request-handler field to struct gb_connection that is set when the connection is enabled. This is a step towards removing the legacy protocol abstraction from core, and will also be used to implement unidirectional connection states (e.g. only outgoing operations are allowed). Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: remove disable from destructorGravatar Johan Hovold 1-2/+0
Remove implicit disable of legacy connections from the destructor. This is a step towards removing the legacy-protocol handling from core. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: connection: rename legacy init and exit functionsGravatar Johan Hovold 1-5/+5
Rename legacy connection init and exit functions. This is a step towards removing the legacy-protocol handling from core. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-19greybus: legacy: add legacy-protocol bundle driverGravatar Johan Hovold 1-0/+2
Add the first Greybus bundle driver that will be used when transitioning from legacy Greybus protocols to bundle drivers. The legacy-protocol driver initially binds to all current bundle classes. In order to avoid having to update current module-loading scripts, keep this driver internal to greybus core at least until modalias support is added. Note that this prevents unloading any protocol drivers without first tearing down the host device due to a circular module dependency. Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-12greybus: connection: refactor connection enable and disableGravatar Johan Hovold 1-24/+45
Refactor connection enable and disable. This is a step towards removing the legacy-protocol handling from core. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-12greybus: connection: fix connection-state handlingGravatar Johan Hovold 1-8/+13
Set connection state to ENABLE before sending the control connected message, and set state DISABLE after sending the control disconnected event. Remove the now unused ERROR connection state. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2016-01-09greybus: connection: fix version-request error handlingGravatar Johan Hovold 1-2/+3
Use the host device and connection name when logging errors as the version-request helper must not assume that all connection have a bundle. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-12-08greybus: use decimal notation for interfaces, bundles and cportsGravatar Johan Hovold 1-1/+1
Fix up the last few places where hexadecimal rather than decimal notation was used for interface, bundle and cport ids. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-12-08greybus: hd: make svc-connection life time coincide with host-deviceGravatar Johan Hovold 1-1/+1
Create the svc-connection as part of the host device, and destroy it in the host-device destructor. The svc-connection is enabled when registering the host device, and disabled when the host device is deregistered. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-12-08greybus: connection: separate connection creation and enablingGravatar Johan Hovold 1-11/+1
Separate connection creation from enabling. This will ultimately allow connection structures to be created while parsing manifests, but the connections to not be enabled until a driver is bound. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-12-08greybus: connection: unbind protocol at exitGravatar Johan Hovold 1-12/+14
Unbind protocol at connection exit rather than when the connection is destroyed. Now a protocol is only bound while a connection is enabled. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-12-08greybus: connection: bind protocol at initGravatar Johan Hovold 1-12/+8
Bind protocol at connection init. This is an intermediate step in separating connection creation and enabling. Note that the protocol is currently still unbound when the connection is destroyed. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-12-08greybus: connection: fail on missing protocolGravatar Johan Hovold 1-2/+2
Make sure to fail properly when a protocol is missing. This prevents the connection from being created, which is fine as we currently never bind protocols post creation. This is an intermediate step in moving protocol binding to connection_init. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-12-08greybus: bundle: kill gb_bundle_bind_protocolsGravatar Johan Hovold 1-1/+5
Remove gb_bundle_bind_protocols() that was used to iterate over all registered bundles and bind protocols to them should a protocol become available post bundle creation. The protocol abstraction as a generic construct is going away in favour of class drivers. Connections will be setup when a class driver is probed, and driver modules can be loaded on-demand by user space based on uevents and modalias. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-12-04greybus: don't use %h and %hh for printing short and char variablesGravatar Viresh Kumar 1-3/+3
Because the width of our fields is already known, we can use %0Nx (for hex) to print N bytes and %u (for unsigned decimal), instead of using %h and %hh, which isn't that readable. This patch makes following changes: - s/%hx/%04x - s/%04hx/%04x - s/%hhx/%02x - s/%02hhx/%02x - s/%hhu/%u - s/%hu/%u - s/%x/%02x for u8 value (only at a single place) Suggested-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: connection: unconditionally enable connectionsGravatar Johan Hovold 1-13/+5
Remove conditional enabling of connections when binding protocols that served no purpose as a connection either has no bundle or it has an interface with a valid device id. Also remove the now unused GB_PROTOCOL_NO_BUNDLE protocol flag. This is an intermediate step in moving the protocol binding to connection_init, but is also needed as the control bundle is going away. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: connection: handle bundle-less connections in svc helpersGravatar Johan Hovold 1-2/+2
The svc connection helper functions should not assume that all dynamic connections will have a bundle. This is needed as the control bundle is going away. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: hd: fix svc-connection handlingGravatar Johan Hovold 1-18/+0
Create the svc connection when registering the host-device and remove the current svc connection hacks that "upgraded" the svc connection once the endo id and ap interface id was known. Note that the old implementation was partly based on a misunderstanding as it was the remote interface id, rather than the local AP interface id, that used to define a connection (but we also needed the endo_id). The remote interface is no longer needed as static connections, such as the svc connection, are now simply defined by the host-device and host cport id. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: connection: handle static connectionsGravatar Johan Hovold 1-8/+11
Use host-device device and connection name for log messages rather than assume that all connections have a bundle (e.g. not true for static connections). Note that the "initial" svc connection has never had a bundle. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: connection: add name fieldGravatar Johan Hovold 1-0/+17
Add a name field to connections that can be used in log messages. A connection always belongs to a host-device (bus) and can be uniquely identified by its host-device cport id, but include remote interface and cport id nonetheless on the following format: <hd_cport_id>/<intf_id>:<cport_id> The remote interface and cport id will be zero for static connections. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: connection: kill GB_PROTOCOL_SKIP_SVC_CONNECTIONGravatar Johan Hovold 1-3/+2
Add helper to determine whether a connection is static, and remove the protocol flag GB_PROTOCOL_SKIP_SVC_CONNECTION. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: connection: fix potential null-deref on createGravatar Johan Hovold 1-2/+4
Make sure that the interface lookup helper can handle static, bundle-less connections without oopsing when creating further connections. Note that the initial svc-connection has always been bundle-less, but did not trigger an oops as a bundle was created for it before further connections were created. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: connection: clean up connection-creation interfaceGravatar Johan Hovold 1-18/+46
Clean up the connection-creation interface by clearly separating our two types of connections: static and dynamic. Add two convenience functions for creating static and dynamic connections. A static connection is a pre-setup connection that is defined by a host device and a host-device cport id. Specifically, the remote interface or cport id need not be known. The SVC connection is a static connection. A dynamic connection is defined by a host device and a remote interface and cport id. This is our normal connections where the host-device cport is (generally) allocated dynamically. Note that the new generic interface is marked static, but can be exported later to allow dynamic connections to be created also from fixed host-device cports (e.g. for CSI). Also note that a connection of either type is uniquely identified by its host-device and host-device cport id once created. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: svc: move endo id and ap interface id to svcGravatar Johan Hovold 1-2/+2
Move endo_id and AP interface id to the svc device. The endo abstraction is about to be removed, and these attributes are arguable attributes of the svc anyway. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: connection: drop parent parameter from connection createGravatar Johan Hovold 1-4/+4
The parent parameter was only used for debug messages and to name the connection workqueue. Use the host-device device for this instead. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2015-11-25greybus: hd: make host device a deviceGravatar Johan Hovold 1-3/+3
Make the host device a proper device in the kernel device model. Host devices will be our new greybus-bus root devices. Signed-off-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>