Add auxiliary bus support
Add support for the Auxiliary Bus, auxiliary_device and auxiliary_driver. It enables drivers to create an auxiliary_device and bind an auxiliary_driver to it. The bus supports probe/remove shutdown and suspend/resume callbacks. Each auxiliary_device has a unique string based id; driver binds to an auxiliary_device based on this id through the bus. Co-developed-by: Kiran Patil <kiran.patil@intel.com> Co-developed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com> Co-developed-by: Fred Oh <fred.oh@linux.intel.com> Co-developed-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Kiran Patil <kiran.patil@intel.com> Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com> Signed-off-by: Fred Oh <fred.oh@linux.intel.com> Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Dave Ertman <david.m.ertman@intel.com> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com> Reviewed-by: Parav Pandit <parav@mellanox.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Martin Habets <mhabets@solarflare.com> Link: https://lore.kernel.org/r/20201113161859.1775473-2-david.m.ertman@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/160695681289.505290.8978295443574440604.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Dave Ertman
Greg Kroah-Hartman
parent
f8394f232b
commit
7de3697e9c
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@ -0,0 +1,234 @@
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.. SPDX-License-Identifier: GPL-2.0-only
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=============
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Auxiliary Bus
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=============
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In some subsystems, the functionality of the core device (PCI/ACPI/other) is
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too complex for a single device to be managed by a monolithic driver
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(e.g. Sound Open Firmware), multiple devices might implement a common
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intersection of functionality (e.g. NICs + RDMA), or a driver may want to
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export an interface for another subsystem to drive (e.g. SIOV Physical Function
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export Virtual Function management). A split of the functinoality into child-
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devices representing sub-domains of functionality makes it possible to
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compartmentalize, layer, and distribute domain-specific concerns via a Linux
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device-driver model.
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An example for this kind of requirement is the audio subsystem where a single
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IP is handling multiple entities such as HDMI, Soundwire, local devices such as
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mics/speakers etc. The split for the core's functionality can be arbitrary or
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be defined by the DSP firmware topology and include hooks for test/debug. This
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allows for the audio core device to be minimal and focused on hardware-specific
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control and communication.
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Each auxiliary_device represents a part of its parent functionality. The
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generic behavior can be extended and specialized as needed by encapsulating an
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auxiliary_device within other domain-specific structures and the use of .ops
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callbacks. Devices on the auxiliary bus do not share any structures and the use
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of a communication channel with the parent is domain-specific.
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Note that ops are intended as a way to augment instance behavior within a class
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of auxiliary devices, it is not the mechanism for exporting common
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infrastructure from the parent. Consider EXPORT_SYMBOL_NS() to convey
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infrastructure from the parent module to the auxiliary module(s).
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When Should the Auxiliary Bus Be Used
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=====================================
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The auxiliary bus is to be used when a driver and one or more kernel modules,
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who share a common header file with the driver, need a mechanism to connect and
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provide access to a shared object allocated by the auxiliary_device's
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registering driver. The registering driver for the auxiliary_device(s) and the
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kernel module(s) registering auxiliary_drivers can be from the same subsystem,
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or from multiple subsystems.
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The emphasis here is on a common generic interface that keeps subsystem
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customization out of the bus infrastructure.
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One example is a PCI network device that is RDMA-capable and exports a child
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device to be driven by an auxiliary_driver in the RDMA subsystem. The PCI
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driver allocates and registers an auxiliary_device for each physical
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function on the NIC. The RDMA driver registers an auxiliary_driver that claims
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each of these auxiliary_devices. This conveys data/ops published by the parent
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PCI device/driver to the RDMA auxiliary_driver.
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Another use case is for the PCI device to be split out into multiple sub
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functions. For each sub function an auxiliary_device is created. A PCI sub
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function driver binds to such devices that creates its own one or more class
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devices. A PCI sub function auxiliary device is likely to be contained in a
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struct with additional attributes such as user defined sub function number and
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optional attributes such as resources and a link to the parent device. These
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attributes could be used by systemd/udev; and hence should be initialized
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before a driver binds to an auxiliary_device.
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A key requirement for utilizing the auxiliary bus is that there is no
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dependency on a physical bus, device, register accesses or regmap support.
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These individual devices split from the core cannot live on the platform bus as
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they are not physical devices that are controlled by DT/ACPI. The same
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argument applies for not using MFD in this scenario as MFD relies on individual
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function devices being physical devices.
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Auxiliary Device
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================
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An auxiliary_device represents a part of its parent device's functionality. It
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is given a name that, combined with the registering drivers KBUILD_MODNAME,
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creates a match_name that is used for driver binding, and an id that combined
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with the match_name provide a unique name to register with the bus subsystem.
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Registering an auxiliary_device is a two-step process. First call
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auxiliary_device_init(), which checks several aspects of the auxiliary_device
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struct and performs a device_initialize(). After this step completes, any
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error state must have a call to auxiliary_device_uninit() in its resolution path.
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The second step in registering an auxiliary_device is to perform a call to
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auxiliary_device_add(), which sets the name of the device and add the device to
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the bus.
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Unregistering an auxiliary_device is also a two-step process to mirror the
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register process. First call auxiliary_device_delete(), then call
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auxiliary_device_uninit().
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.. code-block:: c
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struct auxiliary_device {
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struct device dev;
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const char *name;
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u32 id;
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};
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If two auxiliary_devices both with a match_name "mod.foo" are registered onto
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the bus, they must have unique id values (e.g. "x" and "y") so that the
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registered devices names are "mod.foo.x" and "mod.foo.y". If match_name + id
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are not unique, then the device_add fails and generates an error message.
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The auxiliary_device.dev.type.release or auxiliary_device.dev.release must be
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populated with a non-NULL pointer to successfully register the auxiliary_device.
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The auxiliary_device.dev.parent must also be populated.
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Auxiliary Device Memory Model and Lifespan
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------------------------------------------
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The registering driver is the entity that allocates memory for the
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auxiliary_device and register it on the auxiliary bus. It is important to note
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that, as opposed to the platform bus, the registering driver is wholly
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responsible for the management for the memory used for the driver object.
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A parent object, defined in the shared header file, contains the
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auxiliary_device. It also contains a pointer to the shared object(s), which
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also is defined in the shared header. Both the parent object and the shared
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object(s) are allocated by the registering driver. This layout allows the
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auxiliary_driver's registering module to perform a container_of() call to go
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from the pointer to the auxiliary_device, that is passed during the call to the
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auxiliary_driver's probe function, up to the parent object, and then have
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access to the shared object(s).
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The memory for the auxiliary_device is freed only in its release() callback
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flow as defined by its registering driver.
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The memory for the shared object(s) must have a lifespan equal to, or greater
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than, the lifespan of the memory for the auxiliary_device. The auxiliary_driver
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should only consider that this shared object is valid as long as the
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auxiliary_device is still registered on the auxiliary bus. It is up to the
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registering driver to manage (e.g. free or keep available) the memory for the
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shared object beyond the life of the auxiliary_device.
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The registering driver must unregister all auxiliary devices before its own
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driver.remove() is completed.
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Auxiliary Drivers
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=================
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Auxiliary drivers follow the standard driver model convention, where
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discovery/enumeration is handled by the core, and drivers
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provide probe() and remove() methods. They support power management
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and shutdown notifications using the standard conventions.
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.. code-block:: c
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struct auxiliary_driver {
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int (*probe)(struct auxiliary_device *,
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const struct auxiliary_device_id *id);
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int (*remove)(struct auxiliary_device *);
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void (*shutdown)(struct auxiliary_device *);
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int (*suspend)(struct auxiliary_device *, pm_message_t);
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int (*resume)(struct auxiliary_device *);
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struct device_driver driver;
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const struct auxiliary_device_id *id_table;
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};
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Auxiliary drivers register themselves with the bus by calling
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auxiliary_driver_register(). The id_table contains the match_names of auxiliary
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devices that a driver can bind with.
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Example Usage
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=============
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Auxiliary devices are created and registered by a subsystem-level core device
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that needs to break up its functionality into smaller fragments. One way to
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extend the scope of an auxiliary_device is to encapsulate it within a domain-
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pecific structure defined by the parent device. This structure contains the
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auxiliary_device and any associated shared data/callbacks needed to establish
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the connection with the parent.
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An example is:
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.. code-block:: c
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struct foo {
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struct auxiliary_device auxdev;
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void (*connect)(struct auxiliary_device *auxdev);
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void (*disconnect)(struct auxiliary_device *auxdev);
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void *data;
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};
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The parent device then registers the auxiliary_device by calling
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auxiliary_device_init(), and then auxiliary_device_add(), with the pointer to
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the auxdev member of the above structure. The parent provides a name for the
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auxiliary_device that, combined with the parent's KBUILD_MODNAME, creates a
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match_name that is be used for matching and binding with a driver.
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Whenever an auxiliary_driver is registered, based on the match_name, the
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auxiliary_driver's probe() is invoked for the matching devices. The
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auxiliary_driver can also be encapsulated inside custom drivers that make the
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core device's functionality extensible by adding additional domain-specific ops
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as follows:
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.. code-block:: c
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struct my_ops {
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void (*send)(struct auxiliary_device *auxdev);
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void (*receive)(struct auxiliary_device *auxdev);
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};
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struct my_driver {
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struct auxiliary_driver auxiliary_drv;
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const struct my_ops ops;
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};
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An example of this type of usage is:
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.. code-block:: c
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const struct auxiliary_device_id my_auxiliary_id_table[] = {
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{ .name = "foo_mod.foo_dev" },
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{ },
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};
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const struct my_ops my_custom_ops = {
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.send = my_tx,
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.receive = my_rx,
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};
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const struct my_driver my_drv = {
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.auxiliary_drv = {
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.name = "myauxiliarydrv",
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.id_table = my_auxiliary_id_table,
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.probe = my_probe,
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.remove = my_remove,
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.shutdown = my_shutdown,
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},
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.ops = my_custom_ops,
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};
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@ -72,6 +72,7 @@ available subsections can be seen below.
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thermal/index
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fpga/index
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acpi/index
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auxiliary_bus
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backlight/lp855x-driver.rst
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connector
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console
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@ -1,6 +1,9 @@
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# SPDX-License-Identifier: GPL-2.0
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menu "Generic Driver Options"
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config AUXILIARY_BUS
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bool
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config UEVENT_HELPER
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bool "Support for uevent helper"
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help
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@ -7,6 +7,7 @@ obj-y := component.o core.o bus.o dd.o syscore.o \
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attribute_container.o transport_class.o \
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topology.o container.o property.o cacheinfo.o \
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swnode.o
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obj-$(CONFIG_AUXILIARY_BUS) += auxiliary.o
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obj-$(CONFIG_DEVTMPFS) += devtmpfs.o
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obj-y += power/
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obj-$(CONFIG_ISA_BUS_API) += isa.o
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@ -0,0 +1,268 @@
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// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (c) 2019-2020 Intel Corporation
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*
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* Please see Documentation/driver-api/auxiliary_bus.rst for more information.
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*/
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#define pr_fmt(fmt) "%s:%s: " fmt, KBUILD_MODNAME, __func__
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#include <linux/device.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/pm_domain.h>
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#include <linux/pm_runtime.h>
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#include <linux/string.h>
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#include <linux/auxiliary_bus.h>
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static const struct auxiliary_device_id *auxiliary_match_id(const struct auxiliary_device_id *id,
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const struct auxiliary_device *auxdev)
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{
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for (; id->name[0]; id++) {
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const char *p = strrchr(dev_name(&auxdev->dev), '.');
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int match_size;
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if (!p)
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continue;
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match_size = p - dev_name(&auxdev->dev);
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/* use dev_name(&auxdev->dev) prefix before last '.' char to match to */
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if (strlen(id->name) == match_size &&
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!strncmp(dev_name(&auxdev->dev), id->name, match_size))
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return id;
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}
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return NULL;
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}
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static int auxiliary_match(struct device *dev, struct device_driver *drv)
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{
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struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
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struct auxiliary_driver *auxdrv = to_auxiliary_drv(drv);
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return !!auxiliary_match_id(auxdrv->id_table, auxdev);
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}
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static int auxiliary_uevent(struct device *dev, struct kobj_uevent_env *env)
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{
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const char *name, *p;
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name = dev_name(dev);
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p = strrchr(name, '.');
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return add_uevent_var(env, "MODALIAS=%s%.*s", AUXILIARY_MODULE_PREFIX, (int)(p - name),
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name);
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}
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static const struct dev_pm_ops auxiliary_dev_pm_ops = {
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SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, pm_generic_runtime_resume, NULL)
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SET_SYSTEM_SLEEP_PM_OPS(pm_generic_suspend, pm_generic_resume)
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};
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static int auxiliary_bus_probe(struct device *dev)
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{
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struct auxiliary_driver *auxdrv = to_auxiliary_drv(dev->driver);
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struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
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int ret;
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ret = dev_pm_domain_attach(dev, true);
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if (ret) {
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dev_warn(dev, "Failed to attach to PM Domain : %d\n", ret);
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return ret;
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}
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ret = auxdrv->probe(auxdev, auxiliary_match_id(auxdrv->id_table, auxdev));
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if (ret)
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dev_pm_domain_detach(dev, true);
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return ret;
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}
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static int auxiliary_bus_remove(struct device *dev)
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{
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struct auxiliary_driver *auxdrv = to_auxiliary_drv(dev->driver);
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struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
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int ret = 0;
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if (auxdrv->remove)
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ret = auxdrv->remove(auxdev);
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dev_pm_domain_detach(dev, true);
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return ret;
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}
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static void auxiliary_bus_shutdown(struct device *dev)
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{
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struct auxiliary_driver *auxdrv = to_auxiliary_drv(dev->driver);
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struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
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if (auxdrv->shutdown)
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auxdrv->shutdown(auxdev);
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}
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static struct bus_type auxiliary_bus_type = {
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.name = "auxiliary",
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.probe = auxiliary_bus_probe,
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.remove = auxiliary_bus_remove,
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.shutdown = auxiliary_bus_shutdown,
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.match = auxiliary_match,
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.uevent = auxiliary_uevent,
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.pm = &auxiliary_dev_pm_ops,
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};
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/**
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* auxiliary_device_init - check auxiliary_device and initialize
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* @auxdev: auxiliary device struct
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*
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* This is the first step in the two-step process to register an auxiliary_device.
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*
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* When this function returns an error code, then the device_initialize will *not* have
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* been performed, and the caller will be responsible to free any memory allocated for the
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* auxiliary_device in the error path directly.
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*
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* It returns 0 on success. On success, the device_initialize has been performed. After this
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* point any error unwinding will need to include a call to auxiliary_device_uninit().
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* In this post-initialize error scenario, a call to the device's .release callback will be
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* triggered, and all memory clean-up is expected to be handled there.
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*/
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int auxiliary_device_init(struct auxiliary_device *auxdev)
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{
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struct device *dev = &auxdev->dev;
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if (!dev->parent) {
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pr_err("auxiliary_device has a NULL dev->parent\n");
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return -EINVAL;
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}
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if (!auxdev->name) {
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pr_err("auxiliary_device has a NULL name\n");
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return -EINVAL;
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}
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dev->bus = &auxiliary_bus_type;
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device_initialize(&auxdev->dev);
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return 0;
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}
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EXPORT_SYMBOL_GPL(auxiliary_device_init);
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/**
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* __auxiliary_device_add - add an auxiliary bus device
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* @auxdev: auxiliary bus device to add to the bus
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* @modname: name of the parent device's driver module
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*
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* This is the second step in the two-step process to register an auxiliary_device.
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*
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* This function must be called after a successful call to auxiliary_device_init(), which
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* will perform the device_initialize. This means that if this returns an error code, then a
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* call to auxiliary_device_uninit() must be performed so that the .release callback will
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* be triggered to free the memory associated with the auxiliary_device.
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*
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* The expectation is that users will call the "auxiliary_device_add" macro so that the caller's
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* KBUILD_MODNAME is automatically inserted for the modname parameter. Only if a user requires
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* a custom name would this version be called directly.
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*/
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int __auxiliary_device_add(struct auxiliary_device *auxdev, const char *modname)
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{
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struct device *dev = &auxdev->dev;
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int ret;
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if (!modname) {
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pr_err("auxiliary device modname is NULL\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
ret = dev_set_name(dev, "%s.%s.%d", modname, auxdev->name, auxdev->id);
|
||||
if (ret) {
|
||||
pr_err("auxiliary device dev_set_name failed: %d\n", ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
ret = device_add(dev);
|
||||
if (ret)
|
||||
dev_err(dev, "adding auxiliary device failed!: %d\n", ret);
|
||||
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(__auxiliary_device_add);
|
||||
|
||||
/**
|
||||
* auxiliary_find_device - auxiliary device iterator for locating a particular device.
|
||||
* @start: Device to begin with
|
||||
* @data: Data to pass to match function
|
||||
* @match: Callback function to check device
|
||||
*
|
||||
* This function returns a reference to a device that is 'found'
|
||||
* for later use, as determined by the @match callback.
|
||||
*
|
||||
* The callback should return 0 if the device doesn't match and non-zero
|
||||
* if it does. If the callback returns non-zero, this function will
|
||||
* return to the caller and not iterate over any more devices.
|
||||
*/
|
||||
struct auxiliary_device *
|
||||
auxiliary_find_device(struct device *start, const void *data,
|
||||
int (*match)(struct device *dev, const void *data))
|
||||
{
|
||||
struct device *dev;
|
||||
|
||||
dev = bus_find_device(&auxiliary_bus_type, start, data, match);
|
||||
if (!dev)
|
||||
return NULL;
|
||||
|
||||
return to_auxiliary_dev(dev);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(auxiliary_find_device);
|
||||
|
||||
/**
|
||||
* __auxiliary_driver_register - register a driver for auxiliary bus devices
|
||||
* @auxdrv: auxiliary_driver structure
|
||||
* @owner: owning module/driver
|
||||
* @modname: KBUILD_MODNAME for parent driver
|
||||
*/
|
||||
int __auxiliary_driver_register(struct auxiliary_driver *auxdrv, struct module *owner,
|
||||
const char *modname)
|
||||
{
|
||||
if (WARN_ON(!auxdrv->probe) || WARN_ON(!auxdrv->id_table))
|
||||
return -EINVAL;
|
||||
|
||||
if (auxdrv->name)
|
||||
auxdrv->driver.name = kasprintf(GFP_KERNEL, "%s.%s", modname, auxdrv->name);
|
||||
else
|
||||
auxdrv->driver.name = kasprintf(GFP_KERNEL, "%s", modname);
|
||||
if (!auxdrv->driver.name)
|
||||
return -ENOMEM;
|
||||
|
||||
auxdrv->driver.owner = owner;
|
||||
auxdrv->driver.bus = &auxiliary_bus_type;
|
||||
auxdrv->driver.mod_name = modname;
|
||||
|
||||
return driver_register(&auxdrv->driver);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(__auxiliary_driver_register);
|
||||
|
||||
/**
|
||||
* auxiliary_driver_unregister - unregister a driver
|
||||
* @auxdrv: auxiliary_driver structure
|
||||
*/
|
||||
void auxiliary_driver_unregister(struct auxiliary_driver *auxdrv)
|
||||
{
|
||||
driver_unregister(&auxdrv->driver);
|
||||
kfree(auxdrv->driver.name);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(auxiliary_driver_unregister);
|
||||
|
||||
static int __init auxiliary_bus_init(void)
|
||||
{
|
||||
return bus_register(&auxiliary_bus_type);
|
||||
}
|
||||
|
||||
static void __exit auxiliary_bus_exit(void)
|
||||
{
|
||||
bus_unregister(&auxiliary_bus_type);
|
||||
}
|
||||
|
||||
module_init(auxiliary_bus_init);
|
||||
module_exit(auxiliary_bus_exit);
|
||||
|
||||
MODULE_LICENSE("GPL v2");
|
||||
MODULE_DESCRIPTION("Auxiliary Bus");
|
||||
MODULE_AUTHOR("David Ertman <david.m.ertman@intel.com>");
|
||||
MODULE_AUTHOR("Kiran Patil <kiran.patil@intel.com>");
|
||||
|
|
@ -0,0 +1,78 @@
|
|||
/* SPDX-License-Identifier: GPL-2.0-only */
|
||||
/*
|
||||
* Copyright (c) 2019-2020 Intel Corporation
|
||||
*
|
||||
* Please see Documentation/driver-api/auxiliary_bus.rst for more information.
|
||||
*/
|
||||
|
||||
#ifndef _AUXILIARY_BUS_H_
|
||||
#define _AUXILIARY_BUS_H_
|
||||
|
||||
#include <linux/device.h>
|
||||
#include <linux/mod_devicetable.h>
|
||||
#include <linux/slab.h>
|
||||
|
||||
struct auxiliary_device {
|
||||
struct device dev;
|
||||
const char *name;
|
||||
u32 id;
|
||||
};
|
||||
|
||||
struct auxiliary_driver {
|
||||
int (*probe)(struct auxiliary_device *auxdev, const struct auxiliary_device_id *id);
|
||||
int (*remove)(struct auxiliary_device *auxdev);
|
||||
void (*shutdown)(struct auxiliary_device *auxdev);
|
||||
int (*suspend)(struct auxiliary_device *auxdev, pm_message_t state);
|
||||
int (*resume)(struct auxiliary_device *auxdev);
|
||||
const char *name;
|
||||
struct device_driver driver;
|
||||
const struct auxiliary_device_id *id_table;
|
||||
};
|
||||
|
||||
static inline struct auxiliary_device *to_auxiliary_dev(struct device *dev)
|
||||
{
|
||||
return container_of(dev, struct auxiliary_device, dev);
|
||||
}
|
||||
|
||||
static inline struct auxiliary_driver *to_auxiliary_drv(struct device_driver *drv)
|
||||
{
|
||||
return container_of(drv, struct auxiliary_driver, driver);
|
||||
}
|
||||
|
||||
int auxiliary_device_init(struct auxiliary_device *auxdev);
|
||||
int __auxiliary_device_add(struct auxiliary_device *auxdev, const char *modname);
|
||||
#define auxiliary_device_add(auxdev) __auxiliary_device_add(auxdev, KBUILD_MODNAME)
|
||||
|
||||
static inline void auxiliary_device_uninit(struct auxiliary_device *auxdev)
|
||||
{
|
||||
put_device(&auxdev->dev);
|
||||
}
|
||||
|
||||
static inline void auxiliary_device_delete(struct auxiliary_device *auxdev)
|
||||
{
|
||||
device_del(&auxdev->dev);
|
||||
}
|
||||
|
||||
int __auxiliary_driver_register(struct auxiliary_driver *auxdrv, struct module *owner,
|
||||
const char *modname);
|
||||
#define auxiliary_driver_register(auxdrv) \
|
||||
__auxiliary_driver_register(auxdrv, THIS_MODULE, KBUILD_MODNAME)
|
||||
|
||||
void auxiliary_driver_unregister(struct auxiliary_driver *auxdrv);
|
||||
|
||||
/**
|
||||
* module_auxiliary_driver() - Helper macro for registering an auxiliary driver
|
||||
* @__auxiliary_driver: auxiliary driver struct
|
||||
*
|
||||
* Helper macro for auxiliary drivers which do not do anything special in
|
||||
* module init/exit. This eliminates a lot of boilerplate. Each module may only
|
||||
* use this macro once, and calling it replaces module_init() and module_exit()
|
||||
*/
|
||||
#define module_auxiliary_driver(__auxiliary_driver) \
|
||||
module_driver(__auxiliary_driver, auxiliary_driver_register, auxiliary_driver_unregister)
|
||||
|
||||
struct auxiliary_device *
|
||||
auxiliary_find_device(struct device *start, const void *data,
|
||||
int (*match)(struct device *dev, const void *data));
|
||||
|
||||
#endif /* _AUXILIARY_BUS_H_ */
|
||||
|
|
@ -838,4 +838,12 @@ struct mhi_device_id {
|
|||
kernel_ulong_t driver_data;
|
||||
};
|
||||
|
||||
#define AUXILIARY_NAME_SIZE 32
|
||||
#define AUXILIARY_MODULE_PREFIX "auxiliary:"
|
||||
|
||||
struct auxiliary_device_id {
|
||||
char name[AUXILIARY_NAME_SIZE];
|
||||
kernel_ulong_t driver_data;
|
||||
};
|
||||
|
||||
#endif /* LINUX_MOD_DEVICETABLE_H */
|
||||
|
|
|
|||
|
|
@ -243,5 +243,8 @@ int main(void)
|
|||
DEVID(mhi_device_id);
|
||||
DEVID_FIELD(mhi_device_id, chan);
|
||||
|
||||
DEVID(auxiliary_device_id);
|
||||
DEVID_FIELD(auxiliary_device_id, name);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -1364,6 +1364,13 @@ static int do_mhi_entry(const char *filename, void *symval, char *alias)
|
|||
{
|
||||
DEF_FIELD_ADDR(symval, mhi_device_id, chan);
|
||||
sprintf(alias, MHI_DEVICE_MODALIAS_FMT, *chan);
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int do_auxiliary_entry(const char *filename, void *symval, char *alias)
|
||||
{
|
||||
DEF_FIELD_ADDR(symval, auxiliary_device_id, name);
|
||||
sprintf(alias, AUXILIARY_MODULE_PREFIX "%s", *name);
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
|
@ -1442,6 +1449,7 @@ static const struct devtable devtable[] = {
|
|||
{"tee", SIZE_tee_client_device_id, do_tee_entry},
|
||||
{"wmi", SIZE_wmi_device_id, do_wmi_entry},
|
||||
{"mhi", SIZE_mhi_device_id, do_mhi_entry},
|
||||
{"auxiliary", SIZE_auxiliary_device_id, do_auxiliary_entry},
|
||||
};
|
||||
|
||||
/* Create MODULE_ALIAS() statements.
|
||||
|
|
|
|||
Loading…
Reference in New Issue