Fix OF_finddevice error return value in case of FDT.

According to the open firmware standard, finddevice call has to return
a phandle with value of -1 in case of error.

This commit is to:
- Fix the FDT implementation of this interface (ofw_fdt_finddevice) to
  return (phandle_t)-1 in case of error, instead of 0 as it does now.
- Fix up the callers of OF_finddevice() to compare the return value with
  -1 instead of 0 to check for errors.
- Since phandle_t is unsigned, the return value of OF_finddevice should
  be checked with '== -1' rather than '<= 0' or '> 0', fix up these cases
  as well.

Reported by:	nwhitehorn

Reviewed by:	raj
Approved by:	raj, nwhitehorn

1 files changed, 4 insertions, 4 deletions

diff --git a/sys/arm/mv/common.c b/sys/arm/mv/common.c
index 4596a20..c7beae8 100644
--- a/sys/arm/mv/common.c
+++ b/sys/arm/mv/common.c
@@ -1693,7 +1693,7 @@ fdt_get_ranges(const char *nodename, void *buf, int size, int *tuples,
 	int len, tuple_size, tuples_count;
 
 	node = OF_finddevice(nodename);
-	if (node <= 0)
+	if (node == -1)
 		return (EINVAL);
 
 	if ((fdt_addrsize_cells(node, &addr_cells, &size_cells)) != 0)
@@ -1762,11 +1762,11 @@ win_cpu_from_dt(void)
 	/*
 	 * Retrieve CESA SRAM data.
 	 */
-	if ((node = OF_finddevice("sram")) != 0)
+	if ((node = OF_finddevice("sram")) != -1)
 		if (fdt_is_compatible(node, "mrvl,cesa-sram"))
 			goto moveon;
 
-	if ((node = OF_finddevice("/")) == 0)
+	if ((node = OF_finddevice("/")) != -1)
 		return (ENXIO);
 
 	if ((node = fdt_find_compatible(node, "mrvl,cesa-sram", 0)) == 0)
@@ -1796,7 +1796,7 @@ fdt_win_setup(void)
 	int err, i;
 
 	node = OF_finddevice("/");
-	if (node == 0)
+	if (node == -1)
 		panic("fdt_win_setup: no root node");
 
 	node = fdt_find_compatible(node, "simple-bus", 1);