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-rw-r--r--Documentation/DocBook/device-drivers.tmpl6
-rw-r--r--include/linux/device.h154
2 files changed, 154 insertions, 6 deletions
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl
index 36f63d4..b638e50 100644
--- a/Documentation/DocBook/device-drivers.tmpl
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -96,10 +96,10 @@ X!Iinclude/linux/kobject.h
<chapter id="devdrivers">
<title>Device drivers infrastructure</title>
+ <sect1><title>The Basic Device Driver-Model Structures </title>
+!Iinclude/linux/device.h
+ </sect1>
<sect1><title>Device Drivers Base</title>
-<!--
-X!Iinclude/linux/device.h
--->
!Edrivers/base/driver.c
!Edrivers/base/core.c
!Edrivers/base/class.c
diff --git a/include/linux/device.h b/include/linux/device.h
index 2215d01..4236506 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -47,6 +47,38 @@ extern int __must_check bus_create_file(struct bus_type *,
struct bus_attribute *);
extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
+/**
+ * struct bus_type - The bus type of the device
+ *
+ * @name: The name of the bus.
+ * @bus_attrs: Default attributes of the bus.
+ * @dev_attrs: Default attributes of the devices on the bus.
+ * @drv_attrs: Default attributes of the device drivers on the bus.
+ * @match: Called, perhaps multiple times, whenever a new device or driver
+ * is added for this bus. It should return a nonzero value if the
+ * given device can be handled by the given driver.
+ * @uevent: Called when a device is added, removed, or a few other things
+ * that generate uevents to add the environment variables.
+ * @probe: Called when a new device or driver add to this bus, and callback
+ * the specific driver's probe to initial the matched device.
+ * @remove: Called when a device removed from this bus.
+ * @shutdown: Called at shut-down time to quiesce the device.
+ * @suspend: Called when a device on this bus wants to go to sleep mode.
+ * @resume: Called to bring a device on this bus out of sleep mode.
+ * @pm: Power management operations of this bus, callback the specific
+ * device driver's pm-ops.
+ * @p: The private data of the driver core, only the driver core can
+ * touch this.
+ *
+ * A bus is a channel between the processor and one or more devices. For the
+ * purposes of the device model, all devices are connected via a bus, even if
+ * it is an internal, virtual, "platform" bus. Buses can plug into each other.
+ * A USB controller is usually a PCI device, for example. The device model
+ * represents the actual connections between buses and the devices they control.
+ * A bus is represented by the bus_type structure. It contains the name, the
+ * default attributes, the bus' methods, PM operations, and the driver core's
+ * private data.
+ */
struct bus_type {
const char *name;
struct bus_attribute *bus_attrs;
@@ -119,6 +151,37 @@ extern int bus_unregister_notifier(struct bus_type *bus,
extern struct kset *bus_get_kset(struct bus_type *bus);
extern struct klist *bus_get_device_klist(struct bus_type *bus);
+/**
+ * struct device_driver - The basic device driver structure
+ * @name: Name of the device driver.
+ * @bus: The bus which the device of this driver belongs to.
+ * @owner: The module owner.
+ * @mod_name: Used for built-in modules.
+ * @suppress_bind_attrs: Disables bind/unbind via sysfs.
+ * @of_match_table: The open firmware table.
+ * @probe: Called to query the existence of a specific device,
+ * whether this driver can work with it, and bind the driver
+ * to a specific device.
+ * @remove: Called when the device is removed from the system to
+ * unbind a device from this driver.
+ * @shutdown: Called at shut-down time to quiesce the device.
+ * @suspend: Called to put the device to sleep mode. Usually to a
+ * low power state.
+ * @resume: Called to bring a device from sleep mode.
+ * @groups: Default attributes that get created by the driver core
+ * automatically.
+ * @pm: Power management operations of the device which matched
+ * this driver.
+ * @p: Driver core's private data, no one other than the driver
+ * core can touch this.
+ *
+ * The device driver-model tracks all of the drivers known to the system.
+ * The main reason for this tracking is to enable the driver core to match
+ * up drivers with new devices. Once drivers are known objects within the
+ * system, however, a number of other things become possible. Device drivers
+ * can export information and configuration variables that are independent
+ * of any specific device.
+ */
struct device_driver {
const char *name;
struct bus_type *bus;
@@ -185,8 +248,34 @@ struct device *driver_find_device(struct device_driver *drv,
struct device *start, void *data,
int (*match)(struct device *dev, void *data));
-/*
- * device classes
+/**
+ * struct class - device classes
+ * @name: Name of the class.
+ * @owner: The module owner.
+ * @class_attrs: Default attributes of this class.
+ * @dev_attrs: Default attributes of the devices belong to the class.
+ * @dev_bin_attrs: Default binary attributes of the devices belong to the class.
+ * @dev_kobj: The kobject that represents this class and links it into the hierarchy.
+ * @dev_uevent: Called when a device is added, removed from this class, or a
+ * few other things that generate uevents to add the environment
+ * variables.
+ * @devnode: Callback to provide the devtmpfs.
+ * @class_release: Called to release this class.
+ * @dev_release: Called to release the device.
+ * @suspend: Used to put the device to sleep mode, usually to a low power
+ * state.
+ * @resume: Used to bring the device from the sleep mode.
+ * @ns_type: Callbacks so sysfs can detemine namespaces.
+ * @namespace: Namespace of the device belongs to this class.
+ * @pm: The default device power management operations of this class.
+ * @p: The private data of the driver core, no one other than the
+ * driver core can touch this.
+ *
+ * A class is a higher-level view of a device that abstracts out low-level
+ * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
+ * at the class level, they are all simply disks. Classes allow user space
+ * to work with devices based on what they do, rather than how they are
+ * connected or how they work.
*/
struct class {
const char *name;
@@ -401,6 +490,65 @@ struct device_dma_parameters {
unsigned long segment_boundary_mask;
};
+/**
+ * struct device - The basic device structure
+ * @parent: The device's "parent" device, the device to which it is attached.
+ * In most cases, a parent device is some sort of bus or host
+ * controller. If parent is NULL, the device, is a top-level device,
+ * which is not usually what you want.
+ * @p: Holds the private data of the driver core portions of the device.
+ * See the comment of the struct device_private for detail.
+ * @kobj: A top-level, abstract class from which other classes are derived.
+ * @init_name: Initial name of the device.
+ * @type: The type of device.
+ * This identifies the device type and carries type-specific
+ * information.
+ * @mutex: Mutex to synchronize calls to its driver.
+ * @bus: Type of bus device is on.
+ * @driver: Which driver has allocated this
+ * @platform_data: Platform data specific to the device.
+ * Example: For devices on custom boards, as typical of embedded
+ * and SOC based hardware, Linux often uses platform_data to point
+ * to board-specific structures describing devices and how they
+ * are wired. That can include what ports are available, chip
+ * variants, which GPIO pins act in what additional roles, and so
+ * on. This shrinks the "Board Support Packages" (BSPs) and
+ * minimizes board-specific #ifdefs in drivers.
+ * @power: For device power management.
+ * See Documentation/power/devices.txt for details.
+ * @pwr_domain: Provide callbacks that are executed during system suspend,
+ * hibernation, system resume and during runtime PM transitions
+ * along with subsystem-level and driver-level callbacks.
+ * @numa_node: NUMA node this device is close to.
+ * @dma_mask: Dma mask (if dma'ble device).
+ * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
+ * hardware supports 64-bit addresses for consistent allocations
+ * such descriptors.
+ * @dma_parms: A low level driver may set these to teach IOMMU code about
+ * segment limitations.
+ * @dma_pools: Dma pools (if dma'ble device).
+ * @dma_mem: Internal for coherent mem override.
+ * @archdata: For arch-specific additions.
+ * @of_node: Associated device tree node.
+ * @of_match: Matching of_device_id from driver.
+ * @devt: For creating the sysfs "dev".
+ * @devres_lock: Spinlock to protect the resource of the device.
+ * @devres_head: The resources list of the device.
+ * @knode_class: The node used to add the device to the class list.
+ * @class: The class of the device.
+ * @groups: Optional attribute groups.
+ * @release: Callback to free the device after all references have
+ * gone away. This should be set by the allocator of the
+ * device (i.e. the bus driver that discovered the device).
+ *
+ * At the lowest level, every device in a Linux system is represented by an
+ * instance of struct device. The device structure contains the information
+ * that the device model core needs to model the system. Most subsystems,
+ * however, track additional information about the devices they host. As a
+ * result, it is rare for devices to be represented by bare device structures;
+ * instead, that structure, like kobject structures, is usually embedded within
+ * a higher-level representation of the device.
+ */
struct device {
struct device *parent;
@@ -611,7 +759,7 @@ extern int (*platform_notify)(struct device *dev);
extern int (*platform_notify_remove)(struct device *dev);
-/**
+/*
* get_device - atomically increment the reference count for the device.
*
*/
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