summaryrefslogtreecommitdiff
path: root/include/linux/device.h
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2011-05-19 18:24:11 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-05-19 18:24:11 -0700
commit39ab05c8e0b519ff0a04a869f065746e6e8c3d95 (patch)
treee73f0ba74c4ea7a80dff9b2dd9445a3a74190e28 /include/linux/device.h
parent1477fcc290b3d5c2614bde98bf3b1154c538860d (diff)
parentc42d2237143fcf35cff642cefe2bcf7786aae312 (diff)
Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (44 commits) debugfs: Silence DEBUG_STRICT_USER_COPY_CHECKS=y warning sysfs: remove "last sysfs file:" line from the oops messages drivers/base/memory.c: fix warning due to "memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION" memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION SYSFS: Fix erroneous comments for sysfs_update_group(). driver core: remove the driver-model structures from the documentation driver core: Add the device driver-model structures to kerneldoc Translated Documentation/email-clients.txt RAW driver: Remove call to kobject_put(). reboot: disable usermodehelper to prevent fs access efivars: prevent oops on unload when efi is not enabled Allow setting of number of raw devices as a module parameter Introduce CONFIG_GOOGLE_FIRMWARE driver: Google Memory Console driver: Google EFI SMI x86: Better comments for get_bios_ebda() x86: get_bios_ebda_length() misc: fix ti-st build issues params.c: Use new strtobool function to process boolean inputs debugfs: move to new strtobool ... Fix up trivial conflicts in fs/debugfs/file.c due to the same patch being applied twice, and an unrelated cleanup nearby.
Diffstat (limited to 'include/linux/device.h')
-rw-r--r--include/linux/device.h164
1 files changed, 158 insertions, 6 deletions
diff --git a/include/linux/device.h b/include/linux/device.h
index 0d7535000821..c66111affca9 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;
@@ -408,7 +556,7 @@ struct device {
struct kobject kobj;
const char *init_name; /* initial name of the device */
- struct device_type *type;
+ const struct device_type *type;
struct mutex mutex; /* mutex to synchronize calls to
* its driver.
@@ -556,7 +704,7 @@ extern int device_move(struct device *dev, struct device *new_parent,
extern const char *device_get_devnode(struct device *dev,
mode_t *mode, const char **tmp);
extern void *dev_get_drvdata(const struct device *dev);
-extern void dev_set_drvdata(struct device *dev, void *data);
+extern int dev_set_drvdata(struct device *dev, void *data);
/*
* Root device objects for grouping under /sys/devices
@@ -610,7 +758,7 @@ 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.
*
*/
@@ -734,13 +882,17 @@ do { \
#endif
/*
- * dev_WARN() acts like dev_printk(), but with the key difference
+ * dev_WARN*() acts like dev_printk(), but with the key difference
* of using a WARN/WARN_ON to get the message out, including the
* file/line information and a backtrace.
*/
#define dev_WARN(dev, format, arg...) \
WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
+#define dev_WARN_ONCE(dev, condition, format, arg...) \
+ WARN_ONCE(condition, "Device %s\n" format, \
+ dev_driver_string(dev), ## arg)
+
/* Create alias, so I can be autoloaded. */
#define MODULE_ALIAS_CHARDEV(major,minor) \
MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))