[PATCH linux-next] powerpc/powermac: Add missing of_node_put

[Nicolas Palix <npalix@diku.dk>]

of_node_put is needed before discarding a value received from
of_find_node_by_name, eg in error handling code or when the device
node is no longer used.

The semantic match that catches the bug is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression struct device_node *n;
position p1, p2;
struct device_node *n1;
statement S;
identifier f;
expression E;
expression *ptr != NULL;
@@

n@p1 = of_find_node_by_name(...)
...
if (!n) S
... when != of_node_put(n)
    when != n1 = f(n,...)
    when != E = n
    when any
    when strict
(
  return \(0\|<+...n...+>\|ptr\);
|
return@p2 ...;
|
  of_node_put(n);
|
  n1 = f(n,...)
|
  E = n
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

print "* file: %s of_find_node_by_name %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>

Signed-off-by: Nicolas Palix <npalix@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
---
 arch/powerpc/platforms/powermac/pci.c     |    2 ++
 arch/powerpc/platforms/powermac/time.c    |    4 +++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powermac/pci.c b/arch/powerpc/platforms/powermac/pci.c
index bcf50d7..800fcce 100644
--- a/arch/powerpc/platforms/powermac/pci.c
+++ b/arch/powerpc/platforms/powermac/pci.c
@@ -661,6 +661,7 @@ static void __init init_second_ohare(void)
 			pci_find_hose_for_OF_device(np);
 		if (!hose) {
 			printk(KERN_ERR "Can't find PCI hose for OHare2 !\n");
+			of_node_put(np);
 			return;
 		}
 		early_read_config_word(hose, bus, devfn, PCI_COMMAND, &cmd);
@@ -669,6 +670,7 @@ static void __init init_second_ohare(void)
 		early_write_config_word(hose, bus, devfn, PCI_COMMAND, cmd);
 	}
 	has_second_ohare = 1;
+	of_node_put(np);
 }
 
 /*
diff --git a/arch/powerpc/platforms/powermac/time.c b/arch/powerpc/platforms/powermac/time.c
index 59eb840..394593c 100644
--- a/arch/powerpc/platforms/powermac/time.c
+++ b/arch/powerpc/platforms/powermac/time.c
@@ -265,12 +265,14 @@ int __init via_calibrate_decr(void)
 	struct resource rsrc;
 
 	vias = of_find_node_by_name(NULL, "via-cuda");
 	if (vias = 0)
 		vias = of_find_node_by_name(NULL, "via-pmu");
 	if (vias = 0)
 		vias = of_find_node_by_name(NULL, "via");
 	if (vias = 0 || of_address_to_resource(vias, 0, &rsrc))
 		return 0;
+	of_node_put(vias);
+
 	via = ioremap(rsrc.start, rsrc.end - rsrc.start + 1);
 	if (via = NULL) {
 		printk(KERN_ERR "Failed to map VIA for timer calibration !\n");
@@ -297,7 +299,7 @@ int __init via_calibrate_decr(void)
 	ppc_tb_freq = (dstart - dend) * 100 / 6;
 
 	iounmap(via);
-	
+
 	return 1;
 }
 #endif
-- 
Nicolas Palix