€•i½      Œsphinx.addnodes”Œdocument”“”)”}”(Œ	rawsource”Œ ”Œchildren”]”(Œtranslations”ŒLanguagesNode”“”)”}”(hhh]”(h Œpending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ
attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ	refdomain”Œstd”Œreftype”Œdoc”Œ	reftarget”Œ3/translations/zh_CN/driver-api/driver-model/porting”Œmodname”NŒ	classname”NŒrefexplicit”ˆuŒtagname”hhhubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/zh_TW/driver-api/driver-model/porting”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/it_IT/driver-api/driver-model/porting”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/ja_JP/driver-api/driver-model/porting”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/ko_KR/driver-api/driver-model/porting”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒSpanish”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/sp_SP/driver-api/driver-model/porting”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h
hhŒ	_document”hŒsource”NŒline”NubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒ'Porting Drivers to the New Driver Model”h]”hŒ'Porting Drivers to the New Driver Model”…””}”(hh¨hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hh£hžhhŸŒM/var/lib/git/docbuild/linux/Documentation/driver-api/driver-model/porting.rst”h KubhŒ	paragraph”“”)”}”(hŒPatrick Mochel”h]”hŒPatrick Mochel”…””}”(hh¹hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¸)”}”(hŒ7 January 2003”h]”hŒ7 January 2003”…””}”(hhÇhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¸)”}”(hŒOverview”h]”hŒOverview”…””}”(hhÕhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K
hh£hžhubh¸)”}”(hŒsPlease refer to `Documentation/driver-api/driver-model/*.rst` for definitions of
various driver types and concepts.”h]”(hŒPlease refer to ”…””}”(hhãhžhhŸNh NubhŒtitle_reference”“”)”}”(hŒ-`Documentation/driver-api/driver-model/*.rst`”h]”hŒ+Documentation/driver-api/driver-model/*.rst”…””}”(hhíhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hëhhãubhŒ6 for definitions of
various driver types and concepts.”…””}”(hhãhžhhŸNh Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¸)”}”(hŒØMost of the work of porting devices drivers to the new model happens
at the bus driver layer. This was intentional, to minimize the
negative effect on kernel drivers, and to allow a gradual transition
of bus drivers.”h]”hŒØMost of the work of porting devices drivers to the new model happens
at the bus driver layer. This was intentional, to minimize the
negative effect on kernel drivers, and to allow a gradual transition
of bus drivers.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¸)”}”(hŒÂIn a nutshell, the driver model consists of a set of objects that can
be embedded in larger, bus-specific objects. Fields in these generic
objects can replace fields in the bus-specific objects.”h]”hŒÂIn a nutshell, the driver model consists of a set of objects that can
be embedded in larger, bus-specific objects. Fields in these generic
objects can replace fields in the bus-specific objects.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¸)”}”(hŒœThe generic objects must be registered with the driver model core. By
doing so, they will exported via the sysfs filesystem. sysfs can be
mounted by doing::”h]”hŒ›The generic objects must be registered with the driver model core. By
doing so, they will exported via the sysfs filesystem. sysfs can be
mounted by doing:”…””}”(hj!  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubhŒliteral_block”“”)”}”(hŒ# mount -t sysfs sysfs /sys”h]”hŒ# mount -t sysfs sysfs /sys”…””}”hj1  sbah}”(h]”h ]”h"]”h$]”h&]”Œ	xml:space”Œpreserve”uh1j/  hŸh¶h Khh£hžhubh¸)”}”(hŒThe Process”h]”hŒThe Process”…””}”(hjA  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K hh£hžhubh¸)”}”(hŒHStep 0: Read include/linux/device.h for object and function definitions.”h]”hŒHStep 0: Read include/linux/device.h for object and function definitions.”…””}”(hjO  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K"hh£hžhubh¸)”}”(hŒ#Step 1: Registering the bus driver.”h]”hŒ#Step 1: Registering the bus driver.”…””}”(hj]  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K$hh£hžhubhŒbullet_list”“”)”}”(hhh]”(hŒ	list_item”“”)”}”(hŒyDefine a struct bus_type for the bus driver::

  struct bus_type pci_bus_type = {
        .name           = "pci",
  };

”h]”(h¸)”}”(hŒ-Define a struct bus_type for the bus driver::”h]”hŒ,Define a struct bus_type for the bus driver:”…””}”(hjv  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K'hjr  ubj0  )”}”(hŒBstruct bus_type pci_bus_type = {
      .name           = "pci",
};”h]”hŒBstruct bus_type pci_bus_type = {
      .name           = "pci",
};”…””}”hj„  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h K)hjr  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjm  hžhhŸh¶h Nubjq  )”}”(hX£  Register the bus type.

This should be done in the initialization function for the bus type,
which is usually the module_init(), or equivalent, function::

  static int __init pci_driver_init(void)
  {
          return bus_register(&pci_bus_type);
  }

  subsys_initcall(pci_driver_init);


The bus type may be unregistered (if the bus driver may be compiled
as a module) by doing::

   bus_unregister(&pci_bus_type);

”h]”(h¸)”}”(hŒRegister the bus type.”h]”hŒRegister the bus type.”…””}”(hjœ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K.hj˜  ubh¸)”}”(hŒ‚This should be done in the initialization function for the bus type,
which is usually the module_init(), or equivalent, function::”h]”hŒThis should be done in the initialization function for the bus type,
which is usually the module_init(), or equivalent, function:”…””}”(hjª  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K0hj˜  ubj0  )”}”(hŒzstatic int __init pci_driver_init(void)
{
        return bus_register(&pci_bus_type);
}

subsys_initcall(pci_driver_init);”h]”hŒzstatic int __init pci_driver_init(void)
{
        return bus_register(&pci_bus_type);
}

subsys_initcall(pci_driver_init);”…””}”hj¸  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h K3hj˜  ubh¸)”}”(hŒ[The bus type may be unregistered (if the bus driver may be compiled
as a module) by doing::”h]”hŒZThe bus type may be unregistered (if the bus driver may be compiled
as a module) by doing:”…””}”(hjÆ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K;hj˜  ubj0  )”}”(hŒbus_unregister(&pci_bus_type);”h]”hŒbus_unregister(&pci_bus_type);”…””}”hjÔ  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h K>hj˜  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjm  hžhhŸh¶h Nubjq  )”}”(hŒ”Export the bus type for others to use.

Other code may wish to reference the bus type, so declare it in a
shared header file and export the symbol.
”h]”(h¸)”}”(hŒ&Export the bus type for others to use.”h]”hŒ&Export the bus type for others to use.”…””}”(hjì  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KAhjè  ubh¸)”}”(hŒkOther code may wish to reference the bus type, so declare it in a
shared header file and export the symbol.”h]”hŒkOther code may wish to reference the bus type, so declare it in a
shared header file and export the symbol.”…””}”(hjú  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KChjè  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjm  hžhhŸh¶h Nubeh}”(h]”h ]”h"]”h$]”h&]”Œbullet”Œ-”uh1jk  hŸh¶h K'hh£hžhubh¸)”}”(hŒFrom include/linux/pci.h::”h]”hŒFrom include/linux/pci.h:”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KFhh£hžhubj0  )”}”(hŒ$extern struct bus_type pci_bus_type;”h]”hŒ$extern struct bus_type pci_bus_type;”…””}”hj$  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h KHhh£hžhubh¸)”}”(hŒ%From file the above code appears in::”h]”hŒ$From file the above code appears in:”…””}”(hj2  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KKhh£hžhubj0  )”}”(hŒEXPORT_SYMBOL(pci_bus_type);”h]”hŒEXPORT_SYMBOL(pci_bus_type);”…””}”hj@  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h KMhh£hžhubjl  )”}”(hhh]”jq  )”}”(hŒ°This will cause the bus to show up in /sys/bus/pci/ with two
subdirectories: 'devices' and 'drivers'::

  # tree -d /sys/bus/pci/
  /sys/bus/pci/
  |-- devices
  `-- drivers


”h]”(h¸)”}”(hŒfThis will cause the bus to show up in /sys/bus/pci/ with two
subdirectories: 'devices' and 'drivers'::”h]”hŒmThis will cause the bus to show up in /sys/bus/pci/ with two
subdirectories: â€˜devicesâ€™ and â€˜driversâ€™:”…””}”(hjU  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KQhjQ  ubj0  )”}”(hŒ=# tree -d /sys/bus/pci/
/sys/bus/pci/
|-- devices
`-- drivers”h]”hŒ=# tree -d /sys/bus/pci/
/sys/bus/pci/
|-- devices
`-- drivers”…””}”hjc  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h KThjQ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjN  hžhhŸh¶h Nubah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1jk  hŸh¶h KQhh£hžhubh¸)”}”(hŒStep 2: Registering Devices.”h]”hŒStep 2: Registering Devices.”…””}”(hj}  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K[hh£hžhubh¸)”}”(hŒƒstruct device represents a single device. It mainly contains metadata
describing the relationship the device has to other entities.”h]”hŒƒstruct device represents a single device. It mainly contains metadata
describing the relationship the device has to other entities.”…””}”(hj‹  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K]hh£hžhubjl  )”}”(hhh]”(jq  )”}”(hXÝ  Embed a struct device in the bus-specific device type::


  struct pci_dev {
         ...
         struct  device  dev;            /* Generic device interface */
         ...
  };

It is recommended that the generic device not be the first item in
the struct to discourage programmers from doing mindless casts
between the object types. Instead macros, or inline functions,
should be created to convert from the generic object type::


  #define to_pci_dev(n) container_of(n, struct pci_dev, dev)

  or

  static inline struct pci_dev * to_pci_dev(struct kobject * kobj)
  {
      return container_of(n, struct pci_dev, dev);
  }

This allows the compiler to verify type-safety of the operations
that are performed (which is Good).

”h]”(h¸)”}”(hŒ7Embed a struct device in the bus-specific device type::”h]”hŒ6Embed a struct device in the bus-specific device type:”…””}”(hj   hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kahjœ  ubj0  )”}”(hŒostruct pci_dev {
       ...
       struct  device  dev;            /* Generic device interface */
       ...
};”h]”hŒostruct pci_dev {
       ...
       struct  device  dev;            /* Generic device interface */
       ...
};”…””}”hj®  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h Kdhjœ  ubh¸)”}”(hŒüIt is recommended that the generic device not be the first item in
the struct to discourage programmers from doing mindless casts
between the object types. Instead macros, or inline functions,
should be created to convert from the generic object type::”h]”hŒûIt is recommended that the generic device not be the first item in
the struct to discourage programmers from doing mindless casts
between the object types. Instead macros, or inline functions,
should be created to convert from the generic object type:”…””}”(hj¼  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kjhjœ  ubj0  )”}”(hŒµ#define to_pci_dev(n) container_of(n, struct pci_dev, dev)

or

static inline struct pci_dev * to_pci_dev(struct kobject * kobj)
{
    return container_of(n, struct pci_dev, dev);
}”h]”hŒµ#define to_pci_dev(n) container_of(n, struct pci_dev, dev)

or

static inline struct pci_dev * to_pci_dev(struct kobject * kobj)
{
    return container_of(n, struct pci_dev, dev);
}”…””}”hjÊ  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h Kphjœ  ubh¸)”}”(hŒdThis allows the compiler to verify type-safety of the operations
that are performed (which is Good).”h]”hŒdThis allows the compiler to verify type-safety of the operations
that are performed (which is Good).”…””}”(hjØ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kyhjœ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hj™  hžhhŸh¶h Nubjq  )”}”(hX  Initialize the device on registration.

When devices are discovered or registered with the bus type, the
bus driver should initialize the generic device. The most important
things to initialize are the bus_id, parent, and bus fields.

The bus_id is an ASCII string that contains the device's address on
the bus. The format of this string is bus-specific. This is
necessary for representing devices in sysfs.

parent is the physical parent of the device. It is important that
the bus driver sets this field correctly.

The driver model maintains an ordered list of devices that it uses
for power management. This list must be in order to guarantee that
devices are shutdown before their physical parents, and vice versa.
The order of this list is determined by the parent of registered
devices.

Also, the location of the device's sysfs directory depends on a
device's parent. sysfs exports a directory structure that mirrors
the device hierarchy. Accurately setting the parent guarantees that
sysfs will accurately represent the hierarchy.

The device's bus field is a pointer to the bus type the device
belongs to. This should be set to the bus_type that was declared
and initialized before.

Optionally, the bus driver may set the device's name and release
fields.

The name field is an ASCII string describing the device, like

   "ATI Technologies Inc Radeon QD"

The release field is a callback that the driver model core calls
when the device has been removed, and all references to it have
been released. More on this in a moment.

”h]”(h¸)”}”(hŒ&Initialize the device on registration.”h]”hŒ&Initialize the device on registration.”…””}”(hjð  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K}hjì  ubh¸)”}”(hŒÁWhen devices are discovered or registered with the bus type, the
bus driver should initialize the generic device. The most important
things to initialize are the bus_id, parent, and bus fields.”h]”hŒÁWhen devices are discovered or registered with the bus type, the
bus driver should initialize the generic device. The most important
things to initialize are the bus_id, parent, and bus fields.”…””}”(hjþ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khjì  ubh¸)”}”(hŒ¬The bus_id is an ASCII string that contains the device's address on
the bus. The format of this string is bus-specific. This is
necessary for representing devices in sysfs.”h]”hŒ®The bus_id is an ASCII string that contains the deviceâ€™s address on
the bus. The format of this string is bus-specific. This is
necessary for representing devices in sysfs.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kƒhjì  ubh¸)”}”(hŒkparent is the physical parent of the device. It is important that
the bus driver sets this field correctly.”h]”hŒkparent is the physical parent of the device. It is important that
the bus driver sets this field correctly.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K‡hjì  ubh¸)”}”(hX  The driver model maintains an ordered list of devices that it uses
for power management. This list must be in order to guarantee that
devices are shutdown before their physical parents, and vice versa.
The order of this list is determined by the parent of registered
devices.”h]”hX  The driver model maintains an ordered list of devices that it uses
for power management. This list must be in order to guarantee that
devices are shutdown before their physical parents, and vice versa.
The order of this list is determined by the parent of registered
devices.”…””}”(hj(  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KŠhjì  ubh¸)”}”(hŒôAlso, the location of the device's sysfs directory depends on a
device's parent. sysfs exports a directory structure that mirrors
the device hierarchy. Accurately setting the parent guarantees that
sysfs will accurately represent the hierarchy.”h]”hŒøAlso, the location of the deviceâ€™s sysfs directory depends on a
deviceâ€™s parent. sysfs exports a directory structure that mirrors
the device hierarchy. Accurately setting the parent guarantees that
sysfs will accurately represent the hierarchy.”…””}”(hj6  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khjì  ubh¸)”}”(hŒ—The device's bus field is a pointer to the bus type the device
belongs to. This should be set to the bus_type that was declared
and initialized before.”h]”hŒ™The deviceâ€™s bus field is a pointer to the bus type the device
belongs to. This should be set to the bus_type that was declared
and initialized before.”…””}”(hjD  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K•hjì  ubh¸)”}”(hŒHOptionally, the bus driver may set the device's name and release
fields.”h]”hŒJOptionally, the bus driver may set the deviceâ€™s name and release
fields.”…””}”(hjR  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K™hjì  ubh¸)”}”(hŒ=The name field is an ASCII string describing the device, like”h]”hŒ=The name field is an ASCII string describing the device, like”…””}”(hj`  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kœhjì  ubhŒblock_quote”“”)”}”(hŒ!"ATI Technologies Inc Radeon QD"
”h]”h¸)”}”(hŒ "ATI Technologies Inc Radeon QD"”h]”hŒ$â€œATI Technologies Inc Radeon QDâ€”…””}”(hjt  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kžhjp  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jn  hŸh¶h Kžhjì  ubh¸)”}”(hŒ©The release field is a callback that the driver model core calls
when the device has been removed, and all references to it have
been released. More on this in a moment.”h]”hŒ©The release field is a callback that the driver model core calls
when the device has been removed, and all references to it have
been released. More on this in a moment.”…””}”(hjˆ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K hjì  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hj™  hžhhŸh¶h Nubjq  )”}”(hX<  Register the device.

Once the generic device has been initialized, it can be registered
with the driver model core by doing::

     device_register(&dev->dev);

It can later be unregistered by doing::

     device_unregister(&dev->dev);

This should happen on buses that support hotpluggable devices.
If a bus driver unregisters a device, it should not immediately free
it. It should instead wait for the driver model core to call the
device's release method, then free the bus-specific object.
(There may be other code that is currently referencing the device
structure, and it would be rude to free the device while that is
happening).


When the device is registered, a directory in sysfs is created.
The PCI tree in sysfs looks like::

  /sys/devices/pci0/
  |-- 00:00.0
  |-- 00:01.0
  |   `-- 01:00.0
  |-- 00:02.0
  |   `-- 02:1f.0
  |       `-- 03:00.0
  |-- 00:1e.0
  |   `-- 04:04.0
  |-- 00:1f.0
  |-- 00:1f.1
  |   |-- ide0
  |   |   |-- 0.0
  |   |   `-- 0.1
  |   `-- ide1
  |       `-- 1.0
  |-- 00:1f.2
  |-- 00:1f.3
  `-- 00:1f.5

Also, symlinks are created in the bus's 'devices' directory
that point to the device's directory in the physical hierarchy::

  /sys/bus/pci/devices/
  |-- 00:00.0 -> ../../../devices/pci0/00:00.0
  |-- 00:01.0 -> ../../../devices/pci0/00:01.0
  |-- 00:02.0 -> ../../../devices/pci0/00:02.0
  |-- 00:1e.0 -> ../../../devices/pci0/00:1e.0
  |-- 00:1f.0 -> ../../../devices/pci0/00:1f.0
  |-- 00:1f.1 -> ../../../devices/pci0/00:1f.1
  |-- 00:1f.2 -> ../../../devices/pci0/00:1f.2
  |-- 00:1f.3 -> ../../../devices/pci0/00:1f.3
  |-- 00:1f.5 -> ../../../devices/pci0/00:1f.5
  |-- 01:00.0 -> ../../../devices/pci0/00:01.0/01:00.0
  |-- 02:1f.0 -> ../../../devices/pci0/00:02.0/02:1f.0
  |-- 03:00.0 -> ../../../devices/pci0/00:02.0/02:1f.0/03:00.0
  `-- 04:04.0 -> ../../../devices/pci0/00:1e.0/04:04.0


”h]”(h¸)”}”(hŒRegister the device.”h]”hŒRegister the device.”…””}”(hj   hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¥hjœ  ubh¸)”}”(hŒhOnce the generic device has been initialized, it can be registered
with the driver model core by doing::”h]”hŒgOnce the generic device has been initialized, it can be registered
with the driver model core by doing:”…””}”(hj®  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K§hjœ  ubj0  )”}”(hŒdevice_register(&dev->dev);”h]”hŒdevice_register(&dev->dev);”…””}”hj¼  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h Kªhjœ  ubh¸)”}”(hŒ'It can later be unregistered by doing::”h]”hŒ&It can later be unregistered by doing:”…””}”(hjÊ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¬hjœ  ubj0  )”}”(hŒdevice_unregister(&dev->dev);”h]”hŒdevice_unregister(&dev->dev);”…””}”hjØ  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h K®hjœ  ubh¸)”}”(hX  This should happen on buses that support hotpluggable devices.
If a bus driver unregisters a device, it should not immediately free
it. It should instead wait for the driver model core to call the
device's release method, then free the bus-specific object.
(There may be other code that is currently referencing the device
structure, and it would be rude to free the device while that is
happening).”h]”hX‘  This should happen on buses that support hotpluggable devices.
If a bus driver unregisters a device, it should not immediately free
it. It should instead wait for the driver model core to call the
deviceâ€™s release method, then free the bus-specific object.
(There may be other code that is currently referencing the device
structure, and it would be rude to free the device while that is
happening).”…””}”(hjæ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K°hjœ  ubh¸)”}”(hŒbWhen the device is registered, a directory in sysfs is created.
The PCI tree in sysfs looks like::”h]”hŒaWhen the device is registered, a directory in sysfs is created.
The PCI tree in sysfs looks like:”…””}”(hjô  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¹hjœ  ubj0  )”}”(hX  /sys/devices/pci0/
|-- 00:00.0
|-- 00:01.0
|   `-- 01:00.0
|-- 00:02.0
|   `-- 02:1f.0
|       `-- 03:00.0
|-- 00:1e.0
|   `-- 04:04.0
|-- 00:1f.0
|-- 00:1f.1
|   |-- ide0
|   |   |-- 0.0
|   |   `-- 0.1
|   `-- ide1
|       `-- 1.0
|-- 00:1f.2
|-- 00:1f.3
`-- 00:1f.5”h]”hX  /sys/devices/pci0/
|-- 00:00.0
|-- 00:01.0
|   `-- 01:00.0
|-- 00:02.0
|   `-- 02:1f.0
|       `-- 03:00.0
|-- 00:1e.0
|   `-- 04:04.0
|-- 00:1f.0
|-- 00:1f.1
|   |-- ide0
|   |   |-- 0.0
|   |   `-- 0.1
|   `-- ide1
|       `-- 1.0
|-- 00:1f.2
|-- 00:1f.3
`-- 00:1f.5”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h K¼hjœ  ubh¸)”}”(hŒ|Also, symlinks are created in the bus's 'devices' directory
that point to the device's directory in the physical hierarchy::”h]”hŒƒAlso, symlinks are created in the busâ€™s â€˜devicesâ€™ directory
that point to the deviceâ€™s directory in the physical hierarchy:”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KÐhjœ  ubj0  )”}”(hX†  /sys/bus/pci/devices/
|-- 00:00.0 -> ../../../devices/pci0/00:00.0
|-- 00:01.0 -> ../../../devices/pci0/00:01.0
|-- 00:02.0 -> ../../../devices/pci0/00:02.0
|-- 00:1e.0 -> ../../../devices/pci0/00:1e.0
|-- 00:1f.0 -> ../../../devices/pci0/00:1f.0
|-- 00:1f.1 -> ../../../devices/pci0/00:1f.1
|-- 00:1f.2 -> ../../../devices/pci0/00:1f.2
|-- 00:1f.3 -> ../../../devices/pci0/00:1f.3
|-- 00:1f.5 -> ../../../devices/pci0/00:1f.5
|-- 01:00.0 -> ../../../devices/pci0/00:01.0/01:00.0
|-- 02:1f.0 -> ../../../devices/pci0/00:02.0/02:1f.0
|-- 03:00.0 -> ../../../devices/pci0/00:02.0/02:1f.0/03:00.0
`-- 04:04.0 -> ../../../devices/pci0/00:1e.0/04:04.0”h]”hX†  /sys/bus/pci/devices/
|-- 00:00.0 -> ../../../devices/pci0/00:00.0
|-- 00:01.0 -> ../../../devices/pci0/00:01.0
|-- 00:02.0 -> ../../../devices/pci0/00:02.0
|-- 00:1e.0 -> ../../../devices/pci0/00:1e.0
|-- 00:1f.0 -> ../../../devices/pci0/00:1f.0
|-- 00:1f.1 -> ../../../devices/pci0/00:1f.1
|-- 00:1f.2 -> ../../../devices/pci0/00:1f.2
|-- 00:1f.3 -> ../../../devices/pci0/00:1f.3
|-- 00:1f.5 -> ../../../devices/pci0/00:1f.5
|-- 01:00.0 -> ../../../devices/pci0/00:01.0/01:00.0
|-- 02:1f.0 -> ../../../devices/pci0/00:02.0/02:1f.0
|-- 03:00.0 -> ../../../devices/pci0/00:02.0/02:1f.0/03:00.0
`-- 04:04.0 -> ../../../devices/pci0/00:1e.0/04:04.0”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h KÓhjœ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hj™  hžhhŸh¶h Nubeh}”(h]”h ]”h"]”h$]”h&]”j  j  uh1jk  hŸh¶h Kahh£hžhubh¸)”}”(hŒStep 3: Registering Drivers.”h]”hŒStep 3: Registering Drivers.”…””}”(hj8  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kähh£hžhubh¸)”}”(hŒxstruct device_driver is a simple driver structure that contains a set
of operations that the driver model core may call.”h]”hŒxstruct device_driver is a simple driver structure that contains a set
of operations that the driver model core may call.”…””}”(hjF  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kæhh£hžhubjl  )”}”(hhh]”(jq  )”}”(hŒ¹Embed a struct device_driver in the bus-specific driver.

Just like with devices, do something like::

  struct pci_driver {
         ...
         struct device_driver    driver;
  };

”h]”(h¸)”}”(hŒ8Embed a struct device_driver in the bus-specific driver.”h]”hŒ8Embed a struct device_driver in the bus-specific driver.”…””}”(hj[  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KêhjW  ubh¸)”}”(hŒ+Just like with devices, do something like::”h]”hŒ*Just like with devices, do something like:”…””}”(hji  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KìhjW  ubj0  )”}”(hŒHstruct pci_driver {
       ...
       struct device_driver    driver;
};”h]”hŒHstruct pci_driver {
       ...
       struct device_driver    driver;
};”…””}”hjw  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h KîhjW  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjT  hžhhŸh¶h Nubjq  )”}”(hŒ¾Initialize the generic driver structure.

When the driver registers with the bus (e.g. doing pci_register_driver()),
initialize the necessary fields of the driver: the name and bus
fields.

”h]”(h¸)”}”(hŒ(Initialize the generic driver structure.”h]”hŒ(Initialize the generic driver structure.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kôhj‹  ubh¸)”}”(hŒ’When the driver registers with the bus (e.g. doing pci_register_driver()),
initialize the necessary fields of the driver: the name and bus
fields.”h]”hŒ’When the driver registers with the bus (e.g. doing pci_register_driver()),
initialize the necessary fields of the driver: the name and bus
fields.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Köhj‹  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjT  hžhhŸh¶h Nubjq  )”}”(hX‡  Register the driver.

After the generic driver has been initialized, call::

      driver_register(&drv->driver);

to register the driver with the core.

When the driver is unregistered from the bus, unregister it from the
core by doing::

      driver_unregister(&drv->driver);

Note that this will block until all references to the driver have
gone away. Normally, there will not be any.

”h]”(h¸)”}”(hŒRegister the driver.”h]”hŒRegister the driver.”…””}”(hjµ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kûhj±  ubh¸)”}”(hŒ5After the generic driver has been initialized, call::”h]”hŒ4After the generic driver has been initialized, call:”…””}”(hjÃ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kýhj±  ubj0  )”}”(hŒdriver_register(&drv->driver);”h]”hŒdriver_register(&drv->driver);”…””}”hjÑ  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h Kÿhj±  ubh¸)”}”(hŒ%to register the driver with the core.”h]”hŒ%to register the driver with the core.”…””}”(hjß  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhj±  ubh¸)”}”(hŒTWhen the driver is unregistered from the bus, unregister it from the
core by doing::”h]”hŒSWhen the driver is unregistered from the bus, unregister it from the
core by doing:”…””}”(hjí  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhj±  ubj0  )”}”(hŒ driver_unregister(&drv->driver);”h]”hŒ driver_unregister(&drv->driver);”…””}”hjû  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h Mhj±  ubh¸)”}”(hŒmNote that this will block until all references to the driver have
gone away. Normally, there will not be any.”h]”hŒmNote that this will block until all references to the driver have
gone away. Normally, there will not be any.”…””}”(hj	  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhj±  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjT  hžhhŸh¶h Nubjq  )”}”(hŒÑSysfs representation.

Drivers are exported via sysfs in their bus's 'driver's directory.
For example::

  /sys/bus/pci/drivers/
  |-- 3c59x
  |-- Ensoniq AudioPCI
  |-- agpgart-amdk7
  |-- e100
  `-- serial

”h]”(h¸)”}”(hŒSysfs representation.”h]”hŒSysfs representation.”…””}”(hj!  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhj  ubh¸)”}”(hŒPDrivers are exported via sysfs in their bus's 'driver's directory.
For example::”h]”hŒUDrivers are exported via sysfs in their busâ€™s â€˜driverâ€™s directory.
For example:”…””}”(hj/  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhj  ubj0  )”}”(hŒZ/sys/bus/pci/drivers/
|-- 3c59x
|-- Ensoniq AudioPCI
|-- agpgart-amdk7
|-- e100
`-- serial”h]”hŒZ/sys/bus/pci/drivers/
|-- 3c59x
|-- Ensoniq AudioPCI
|-- agpgart-amdk7
|-- e100
`-- serial”…””}”hj=  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h Mhj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjT  hžhhŸh¶h Nubeh}”(h]”h ]”h"]”h$]”h&]”j  j  uh1jk  hŸh¶h Kêhh£hžhubh¸)”}”(hŒ+Step 4: Define Generic Methods for Drivers.”h]”hŒ+Step 4: Define Generic Methods for Drivers.”…””}”(hjW  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhh£hžhubh¸)”}”(hŒÔstruct device_driver defines a set of operations that the driver model
core calls. Most of these operations are probably similar to
operations the bus already defines for drivers, but taking different
parameters.”h]”hŒÔstruct device_driver defines a set of operations that the driver model
core calls. Most of these operations are probably similar to
operations the bus already defines for drivers, but taking different
parameters.”…””}”(hje  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhh£hžhubh¸)”}”(hX  It would be difficult and tedious to force every driver on a bus to
simultaneously convert their drivers to generic format. Instead, the
bus driver should define single instances of the generic methods that
forward call to the bus-specific drivers. For instance::”h]”hX  It would be difficult and tedious to force every driver on a bus to
simultaneously convert their drivers to generic format. Instead, the
bus driver should define single instances of the generic methods that
forward call to the bus-specific drivers. For instance:”…””}”(hjs  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M hh£hžhubj0  )”}”(hXC  static int pci_device_remove(struct device * dev)
{
        struct pci_dev * pci_dev = to_pci_dev(dev);
        struct pci_driver * drv = pci_dev->driver;

        if (drv) {
                if (drv->remove)
                        drv->remove(pci_dev);
                pci_dev->driver = NULL;
        }
        return 0;
}”h]”hXC  static int pci_device_remove(struct device * dev)
{
        struct pci_dev * pci_dev = to_pci_dev(dev);
        struct pci_driver * drv = pci_dev->driver;

        if (drv) {
                if (drv->remove)
                        drv->remove(pci_dev);
                pci_dev->driver = NULL;
        }
        return 0;
}”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h M&hh£hžhubh¸)”}”(hŒUThe generic driver should be initialized with these methods before it
is registered::”h]”hŒTThe generic driver should be initialized with these methods before it
is registered:”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M4hh£hžhubj0  )”}”(hX=  /* initialize common driver fields */
drv->driver.name = drv->name;
drv->driver.bus = &pci_bus_type;
drv->driver.probe = pci_device_probe;
drv->driver.resume = pci_device_resume;
drv->driver.suspend = pci_device_suspend;
drv->driver.remove = pci_device_remove;

/* register with core */
driver_register(&drv->driver);”h]”hX=  /* initialize common driver fields */
drv->driver.name = drv->name;
drv->driver.bus = &pci_bus_type;
drv->driver.probe = pci_device_probe;
drv->driver.resume = pci_device_resume;
drv->driver.suspend = pci_device_suspend;
drv->driver.remove = pci_device_remove;

/* register with core */
driver_register(&drv->driver);”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h M7hh£hžhubh¸)”}”(hŒIdeally, the bus should only initialize the fields if they are not
already set. This allows the drivers to implement their own generic
methods.”h]”hŒIdeally, the bus should only initialize the fields if they are not
already set. This allows the drivers to implement their own generic
methods.”…””}”(hj«  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MChh£hžhubh¸)”}”(hŒ'Step 5: Support generic driver binding.”h]”hŒ'Step 5: Support generic driver binding.”…””}”(hj¹  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MHhh£hžhubh¸)”}”(hŒÙThe model assumes that a device or driver can be dynamically
registered with the bus at any time. When registration happens,
devices must be bound to a driver, or drivers must be bound to all
devices that it supports.”h]”hŒÙThe model assumes that a device or driver can be dynamically
registered with the bus at any time. When registration happens,
devices must be bound to a driver, or drivers must be bound to all
devices that it supports.”…””}”(hjÇ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MJhh£hžhubh¸)”}”(hX  A driver typically contains a list of device IDs that it supports. The
bus driver compares these IDs to the IDs of devices registered with it.
The format of the device IDs, and the semantics for comparing them are
bus-specific, so the generic model does attempt to generalize them.”h]”hX  A driver typically contains a list of device IDs that it supports. The
bus driver compares these IDs to the IDs of devices registered with it.
The format of the device IDs, and the semantics for comparing them are
bus-specific, so the generic model does attempt to generalize them.”…””}”(hjÕ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MOhh£hžhubh¸)”}”(hŒPInstead, a bus may supply a method in struct bus_type that does the
comparison::”h]”hŒOInstead, a bus may supply a method in struct bus_type that does the
comparison:”…””}”(hjã  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MThh£hžhubj0  )”}”(hŒ>int (*match)(struct device * dev, struct device_driver * drv);”h]”hŒ>int (*match)(struct device * dev, struct device_driver * drv);”…””}”hjñ  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h MWhh£hžhubh¸)”}”(hŒÙmatch should return positive value if the driver supports the device,
and zero otherwise. It may also return error code (for example
-EPROBE_DEFER) if determining that given driver supports the device is
not possible.”h]”hŒÙmatch should return positive value if the driver supports the device,
and zero otherwise. It may also return error code (for example
-EPROBE_DEFER) if determining that given driver supports the device is
not possible.”…””}”(hjÿ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MYhh£hžhubh¸)”}”(hŒ„When a device is registered, the bus's list of drivers is iterated
over. bus->match() is called for each one until a match is found.”h]”hŒ†When a device is registered, the busâ€™s list of drivers is iterated
over. bus->match() is called for each one until a match is found.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M^hh£hžhubh¸)”}”(hŒ˜When a driver is registered, the bus's list of devices is iterated
over. bus->match() is called for each device that is not already
claimed by a driver.”h]”hŒšWhen a driver is registered, the busâ€™s list of devices is iterated
over. bus->match() is called for each device that is not already
claimed by a driver.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mahh£hžhubh¸)”}”(hŒæWhen a device is successfully bound to a driver, device->driver is
set, the device is added to a per-driver list of devices, and a
symlink is created in the driver's sysfs directory that points to the
device's physical directory::”h]”hŒéWhen a device is successfully bound to a driver, device->driver is
set, the device is added to a per-driver list of devices, and a
symlink is created in the driverâ€™s sysfs directory that points to the
deviceâ€™s physical directory:”…””}”(hj)  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mehh£hžhubj0  )”}”(hŒö/sys/bus/pci/drivers/
|-- 3c59x
|   `-- 00:0b.0 -> ../../../../devices/pci0/00:0b.0
|-- Ensoniq AudioPCI
|-- agpgart-amdk7
|   `-- 00:00.0 -> ../../../../devices/pci0/00:00.0
|-- e100
|   `-- 00:0c.0 -> ../../../../devices/pci0/00:0c.0
`-- serial”h]”hŒö/sys/bus/pci/drivers/
|-- 3c59x
|   `-- 00:0b.0 -> ../../../../devices/pci0/00:0b.0
|-- Ensoniq AudioPCI
|-- agpgart-amdk7
|   `-- 00:00.0 -> ../../../../devices/pci0/00:00.0
|-- e100
|   `-- 00:0c.0 -> ../../../../devices/pci0/00:0c.0
`-- serial”…””}”hj7  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h Mjhh£hžhubh¸)”}”(hŒ`This driver binding should replace the existing driver binding
mechanism the bus currently uses.”h]”hŒ`This driver binding should replace the existing driver binding
mechanism the bus currently uses.”…””}”(hjE  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Muhh£hžhubh¸)”}”(hŒ"Step 6: Supply a hotplug callback.”h]”hŒ"Step 6: Supply a hotplug callback.”…””}”(hjS  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Myhh£hžhubh¸)”}”(hŒÈWhenever a device is registered with the driver model core, the
userspace program /sbin/hotplug is called to notify userspace.
Users can define actions to perform when a device is inserted or
removed.”h]”hŒÈWhenever a device is registered with the driver model core, the
userspace program /sbin/hotplug is called to notify userspace.
Users can define actions to perform when a device is inserted or
removed.”…””}”(hja  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M{hh£hžhubh¸)”}”(hŒ`The driver model core passes several arguments to userspace via
environment variables, including”h]”hŒ`The driver model core passes several arguments to userspace via
environment variables, including”…””}”(hjo  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M€hh£hžhubjl  )”}”(hhh]”(jq  )”}”(hŒ ACTION: set to 'add' or 'remove'”h]”h¸)”}”(hj‚  h]”hŒ(ACTION: set to â€˜addâ€™ or â€˜removeâ€™”…””}”(hj„  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mƒhj€  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jp  hj}  hžhhŸh¶h Nubjq  )”}”(hŒ5DEVPATH: set to the device's physical path in sysfs.
”h]”h¸)”}”(hŒ4DEVPATH: set to the device's physical path in sysfs.”h]”hŒ6DEVPATH: set to the deviceâ€™s physical path in sysfs.”…””}”(hj›  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M„hj—  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jp  hj}  hžhhŸh¶h Nubeh}”(h]”h ]”h"]”h$]”h&]”j  j  uh1jk  hŸh¶h Mƒhh£hžhubh¸)”}”(hŒ—A bus driver may also supply additional parameters for userspace to
consume. To do this, a bus must implement the 'hotplug' method in
struct bus_type::”h]”hŒšA bus driver may also supply additional parameters for userspace to
consume. To do this, a bus must implement the â€˜hotplugâ€™ method in
struct bus_type:”…””}”(hjµ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M†hh£hžhubj0  )”}”(hŒnint (*hotplug) (struct device *dev, char **envp,
                int num_envp, char *buffer, int buffer_size);”h]”hŒnint (*hotplug) (struct device *dev, char **envp,
                int num_envp, char *buffer, int buffer_size);”…””}”hjÃ  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h MŠhh£hžhubh¸)”}”(hŒ<This is called immediately before /sbin/hotplug is executed.”h]”hŒ<This is called immediately before /sbin/hotplug is executed.”…””}”(hjÑ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhh£hžhubh¸)”}”(hŒ#Step 7: Cleaning up the bus driver.”h]”hŒ#Step 7: Cleaning up the bus driver.”…””}”(hjß  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhh£hžhubh¸)”}”(hŒThe generic bus, device, and driver structures provide several fields
that can replace those defined privately to the bus driver.”h]”hŒThe generic bus, device, and driver structures provide several fields
that can replace those defined privately to the bus driver.”…””}”(hjí  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M’hh£hžhubjl  )”}”(hhh]”jq  )”}”(hŒDevice list.
”h]”h¸)”}”(hŒDevice list.”h]”hŒDevice list.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M•hjþ  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjû  hžhhŸh¶h Nubah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1jk  hŸh¶h M•hh£hžhubh¸)”}”(hŒØstruct bus_type contains a list of all devices registered with the bus
type. This includes all devices on all instances of that bus type.
An internal list that the bus uses may be removed, in favor of using
this one.”h]”hŒØstruct bus_type contains a list of all devices registered with the bus
type. This includes all devices on all instances of that bus type.
An internal list that the bus uses may be removed, in favor of using
this one.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M—hh£hžhubh¸)”}”(hŒ7The core provides an iterator to access these devices::”h]”hŒ6The core provides an iterator to access these devices:”…””}”(hj*  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mœhh£hžhubj0  )”}”(hŒ‰int bus_for_each_dev(struct bus_type * bus, struct device * start,
                     void * data, int (*fn)(struct device *, void *));”h]”hŒ‰int bus_for_each_dev(struct bus_type * bus, struct device * start,
                     void * data, int (*fn)(struct device *, void *));”…””}”hj8  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h Mžhh£hžhubjl  )”}”(hhh]”jq  )”}”(hŒDriver list.
”h]”h¸)”}”(hŒDriver list.”h]”hŒDriver list.”…””}”(hjM  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M¢hjI  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjF  hžhhŸh¶h Nubah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1jk  hŸh¶h M¢hh£hžhubh¸)”}”(hŒ³struct bus_type also contains a list of all drivers registered with
it. An internal list of drivers that the bus driver maintains may
be removed in favor of using the generic one.”h]”hŒ³struct bus_type also contains a list of all drivers registered with
it. An internal list of drivers that the bus driver maintains may
be removed in favor of using the generic one.”…””}”(hjg  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M¤hh£hžhubh¸)”}”(hŒ0The drivers may be iterated over, like devices::”h]”hŒ/The drivers may be iterated over, like devices:”…””}”(hju  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M¨hh£hžhubj0  )”}”(hŒ—int bus_for_each_drv(struct bus_type * bus, struct device_driver * start,
                     void * data, int (*fn)(struct device_driver *, void *));”h]”hŒ—int bus_for_each_drv(struct bus_type * bus, struct device_driver * start,
                     void * data, int (*fn)(struct device_driver *, void *));”…””}”hjƒ  sbah}”(h]”h ]”h"]”h$]”h&]”j?  j@  uh1j/  hŸh¶h Mªhh£hžhubh¸)”}”(hŒ3Please see drivers/base/bus.c for more information.”h]”hŒ3Please see drivers/base/bus.c for more information.”…””}”(hj‘  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M®hh£hžhubjl  )”}”(hhh]”jq  )”}”(hŒrwsem
”h]”h¸)”}”(hŒrwsem”h]”hŒrwsem”…””}”(hj¦  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M±hj¢  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjŸ  hžhhŸh¶h Nubah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1jk  hŸh¶h M±hh£hžhubh¸)”}”(hŒàstruct bus_type contains an rwsem that protects all core accesses to
the device and driver lists. This can be used by the bus driver
internally, and should be used when accessing the device or driver
lists the bus maintains.”h]”hŒàstruct bus_type contains an rwsem that protects all core accesses to
the device and driver lists. This can be used by the bus driver
internally, and should be used when accessing the device or driver
lists the bus maintains.”…””}”(hjÀ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M³hh£hžhubjl  )”}”(hhh]”jq  )”}”(hŒDevice and driver fields.
”h]”h¸)”}”(hŒDevice and driver fields.”h]”hŒDevice and driver fields.”…””}”(hjÕ  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M¹hjÑ  ubah}”(h]”h ]”h"]”h$]”h&]”uh1jp  hjÎ  hžhhŸh¶h Nubah}”(h]”h ]”h"]”h$]”h&]”j  j  uh1jk  hŸh¶h M¹hh£hžhubh¸)”}”(hX_  Some of the fields in struct device and struct device_driver duplicate
fields in the bus-specific representations of these objects. Feel free
to remove the bus-specific ones and favor the generic ones. Note
though, that this will likely mean fixing up all the drivers that
reference the bus-specific fields (though those should all be 1-line
changes).”h]”hX_  Some of the fields in struct device and struct device_driver duplicate
fields in the bus-specific representations of these objects. Feel free
to remove the bus-specific ones and favor the generic ones. Note
though, that this will likely mean fixing up all the drivers that
reference the bus-specific fields (though those should all be 1-line
changes).”…””}”(hjï  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M»hh£hžhubeh}”(h]”Œ'porting-drivers-to-the-new-driver-model”ah ]”h"]”Œ'porting drivers to the new driver model”ah$]”h&]”uh1h¡hhhžhhŸh¶h Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”h¶uh1hŒcurrent_source”NŒcurrent_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(h¦NŒ	generator”NŒ	datestamp”NŒsource_link”NŒ
source_url”NŒtoc_backlinks”Œentry”Œfootnote_backlinks”KŒsectnum_xform”KŒstrip_comments”NŒstrip_elements_with_classes”NŒstrip_classes”NŒreport_level”KŒ
halt_level”KŒexit_status_level”KŒdebug”NŒwarning_stream”NŒ	traceback”ˆŒinput_encoding”Œ	utf-8-sig”Œinput_encoding_error_handler”Œstrict”Œoutput_encoding”Œutf-8”Œoutput_encoding_error_handler”j(  Œerror_encoding”Œutf-8”Œerror_encoding_error_handler”Œbackslashreplace”Œlanguage_code”Œen”Œrecord_dependencies”NŒconfig”NŒ	id_prefix”hŒauto_id_prefix”Œid”Œdump_settings”NŒdump_internals”NŒdump_transforms”NŒdump_pseudo_xml”NŒexpose_internals”NŒstrict_visitor”NŒ_disable_config”NŒ_source”h¶Œ_destination”NŒ_config_files”]”Œ7/var/lib/git/docbuild/linux/Documentation/docutils.conf”aŒfile_insertion_enabled”ˆŒraw_enabled”KŒline_length_limit”M'Œpep_references”NŒpep_base_url”Œhttps://peps.python.org/”Œpep_file_url_template”Œpep-%04d”Œrfc_references”NŒrfc_base_url”Œ&https://datatracker.ietf.org/doc/html/”Œ	tab_width”KŒtrim_footnote_reference_space”‰Œsyntax_highlight”Œlong”Œsmart_quotes”ˆŒsmartquotes_locales”]”Œcharacter_level_inline_markup”‰Œdoctitle_xform”‰Œdocinfo_xform”KŒsectsubtitle_xform”‰Œimage_loading”Œlink”Œembed_stylesheet”‰Œcloak_email_addresses”ˆŒsection_self_link”‰Œenv”NubŒreporter”NŒindirect_targets”]”Œsubstitution_defs”}”Œsubstitution_names”}”Œrefnames”}”Œrefids”}”Œnameids”}”j  jÿ  sŒ	nametypes”}”j  ‰sh}”jÿ  h£sŒfootnote_refs”}”Œcitation_refs”}”Œautofootnotes”]”Œautofootnote_refs”]”Œsymbol_footnotes”]”Œsymbol_footnote_refs”]”Œ	footnotes”]”Œ	citations”]”Œautofootnote_start”KŒsymbol_footnote_start”K Œ
id_counter”Œcollections”ŒCounter”“”}”…”R”Œparse_messages”]”Œtransform_messages”]”Œtransformer”NŒinclude_log”]”Œ
decoration”Nhžhub.