OF_FINDDEVICE(9)       FreeBSD Kernel Developer's Manual      OF_FINDDEVICE(9)

NAME
     OF_finddevice - find node in device tree

SYNOPSIS
     #include <dev/ofw/ofw_bus.h>
     #include <dev/ofw/ofw_bus_subr.h>

     phandle_t
     OF_finddevice(const char *path);

DESCRIPTION
     OF_finddevice() returns the phandle for the node specified by the path.
     Returns -1 if the path cannot be found in the tree.

EXAMPLES
         phandle_t root, i2c;

         root = OF_finddevice("/");
         i2c = OF_finddevice("/soc/axi/i2c@a0e0000");
         if (i2c != -1) {
             ...
         }

SEE ALSO
     OF_child(9) OF_parent(9) OF_peer(9)

AUTHORS
     This manual page was written by Oleksandr Tymoshenko <gonzo@FreeBSD.org>.

CAVEATS
     The return value should only be checked with equality operators (equal
     to, not equal to) and not relational comparison (less than, greater than
     ).  There is a discrepancy between IEEE 1275 standard and FreeBSD's
     internal representation of a phandle: IEEE 1275 requires the return value
     of this function to be -1 if the path is not found.  But phandle_t is an
     unsigned type, so it cannot be relationally compared with -1 or 0, this
     comparison is always true or always false.

FreeBSD 13.1-RELEASE-p6          April 9, 2018         FreeBSD 13.1-RELEASE-p6