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33 .Nd find node in device tree
36 .In dev/ofw/ofw_bus_subr.h
38 .Fn OF_finddevice "const char *path"
41 returns the phandle for the node specified by the
43 Returns -1 if the path cannot be found in the tree.
48 root = OF_finddevice("/");
49 i2c = OF_finddevice("/soc/axi/i2c@a0e0000");
60 This manual page was written by
61 .An Oleksandr Tymoshenko Aq Mt gonzo@FreeBSD.org .
63 The return value should only be checked with equality
64 operators (equal to, not equal to) and not relational comparison
65 (less than, greater than ).
66 There is a discrepancy between IEEE 1275 standard and
68 internal representation of a phandle: IEEE 1275
69 requires the return value of this function to be -1 if the path
71 But phandle_t is an unsigned type, so it cannot
72 be relationally compared with -1 or 0, this comparison
73 is always true or always false.