subsys_dev_iter_init(9) [centos man page]

SUBSYS_DEV_ITER_INIT(9) 				   Device drivers infrastructure				   SUBSYS_DEV_ITER_INIT(9)

NAME

       subsys_dev_iter_init - initialize subsys device iterator

SYNOPSIS

       void subsys_dev_iter_init(struct subsys_dev_iter * iter, struct bus_type * subsys, struct device * start, const struct device_type * type);

ARGUMENTS

       iter
	   subsys iterator to initialize

       subsys
	   the subsys we wanna iterate over

       start
	   the device to start iterating from, if any

       type
	   device_type of the devices to iterate over, NULL for all

DESCRIPTION

       Initialize subsys iterator iter such that it iterates over devices of subsys. If start is set, the list iteration will start there,
       otherwise if it is NULL, the iteration starts at the beginning of the list.

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014						   SUBSYS_DEV_ITER_INIT(9)

DEVITER(9)						   BSD Kernel Developer's Manual						DEVITER(9)

NAME

     deviter, deviter_first, deviter_init, deviter_next, deviter_release -- machine-independent device iteration API

SYNOPSIS

     #include <sys/device.h>

     void
     deviter_init(deviter_t *di, deviter_flags_t flags);

     device_t
     deviter_first(deviter_t *di, deviter_flags_t flags);

     device_t
     deviter_next(deviter_t *di);

     void
     deviter_release(deviter_t *di);

DESCRIPTION

     The machine-independent deviter API lets interrupt handlers running at any priority level and kernel threads iterate over the devices
     attached to the kernel.  Using deviter, it is safe for an interrupt handler or a thread to iterate over devices attached to the kernel while
     another thread attaches or detaches the devices.

DATA TYPES

     Kernel subsystems using deviter may make use of the following data types:

     deviter_flags_t
	      The kernel can iterate over devices for different purposes and in different orders.  The following flags affect device iteration:
		    DEVITER_F_RW
		    DEVITER_F_SHUTDOWN
		    DEVITER_F_LEAVES_FIRST
		    DEVITER_F_ROOT_FIRST

     deviter_t
	      This is a device iteration ``cursor'' or ``iterator''.  It holds iteration state such as the next device to visit.

FUNCTIONS

     deviter_init(di, flags)
	      Initialize the device iterator, di.  Set bits in flags to affect the order of iteration.	Set DEVITER_F_LEAVES_FIRST to visit each
	      device only after visiting its children (visit the leaves of the device tree, first).  Set DEVITER_F_ROOT_FIRST to visit each device
	      before visiting its children (visit the root of the device tree, first).	If you set neither DEVITER_F_LEAVES_FIRST nor
	      DEVITER_F_ROOT_FIRST, deviter returns devices in an arbitrary order.

	      Set DEVITER_F_RW if your purpose for iterating over devices is to modify the device tree by attaching or detaching devices.  Set
	      DEVITER_F_SHUTDOWN if your purpose for iterating over devices is to detach all of the devices during system shutdown.
	      DEVITER_F_SHUTDOWN implies DEVITER_F_RW.

     deviter_next(di)
	      Advance the iterator di to the next device.  deviter_next() returns the current device or NULL if there are no more devices.
	      deviter_next() is undefined if di has not been initialized using deviter_init() or deviter_first().

     deviter_first(di, flags)
	      Initialize the iterator di with flags.  Return the first device according to the ordering indicated by flags and advance di to the
	      second device, or return NULL if there are no devices.  This is equivalent to calling deviter_init(di, flags) and then
	      deviter_next(di).

     deviter_release(di)
	      Release all resources held by the iterator di.  Every iterator that is initialized with deviter_first() or deviter_init() MUST be
	      released.

CODE REFERENCES

     Device iteration is implemented within the files sys/sys/device.h and sys/kern/subr_autoconf.c.

SEE ALSO

     autoconf(9), driver(9)

HISTORY

     deviter appeared in NetBSD 5.0.

AUTHORS

     David Young <dyoung@NetBSD.org>

BSD
								 November 4, 2009							       BSD