[lm-sensors] [PATCH 2/4] hwmon: (smsc47m1) Fix compiler warning

Guenter Roeck linux at roeck-us.net
Wed Mar 28 18:38:26 CEST 2012


Some configurations produce the following compiler warning:

drivers/hwmon/smsc47m1.c: In function 'sm_smsc47m1_init':
drivers/hwmon/smsc47m1.c:938: warning: 'address' may be used uninitialized in this function

While this is a false positive, it can easily be fixed by overloading the return
value from smsc47m1_find with both address and error return code (the address
is an unsigned short and thus never negative). This also reduces module size by
a few bytes (46 bytes for x86_64).

Signed-off-by: Guenter Roeck <linux at roeck-us.net>
---
 drivers/hwmon/smsc47m1.c |   15 ++++++++-------
 1 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/hwmon/smsc47m1.c b/drivers/hwmon/smsc47m1.c
index c590c14..87b9ab0 100644
--- a/drivers/hwmon/smsc47m1.c
+++ b/drivers/hwmon/smsc47m1.c
@@ -491,10 +491,10 @@ static const struct attribute_group smsc47m1_group = {
 	.attrs = smsc47m1_attributes,
 };
 
-static int __init smsc47m1_find(unsigned short *addr,
-				struct smsc47m1_sio_data *sio_data)
+static int __init smsc47m1_find(struct smsc47m1_sio_data *sio_data)
 {
 	u8 val;
+	unsigned short addr;
 
 	superio_enter();
 	val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
@@ -546,9 +546,9 @@ static int __init smsc47m1_find(unsigned short *addr,
 	}
 
 	superio_select();
-	*addr = (superio_inb(SUPERIO_REG_BASE) << 8)
+	addr = (superio_inb(SUPERIO_REG_BASE) << 8)
 	      |  superio_inb(SUPERIO_REG_BASE + 1);
-	if (*addr == 0) {
+	if (addr == 0) {
 		pr_info("Device address not set, will not use\n");
 		superio_exit();
 		return -ENODEV;
@@ -565,7 +565,7 @@ static int __init smsc47m1_find(unsigned short *addr,
 	}
 
 	superio_exit();
-	return 0;
+	return addr;
 }
 
 /* Restore device to its initial state */
@@ -938,8 +938,9 @@ static int __init sm_smsc47m1_init(void)
 	unsigned short address;
 	struct smsc47m1_sio_data sio_data;
 
-	if (smsc47m1_find(&address, &sio_data))
-		return -ENODEV;
+	address = smsc47m1_find(&sio_data);
+	if (address < 0)
+		return address;
 
 	/* Sets global pdev as a side effect */
 	err = smsc47m1_device_add(address, &sio_data);
-- 
1.7.5.4





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