i2c: sis630: Fix an error handling path in sis630_probe()

If i2c_add_adapter() fails, the request_region() call in sis630_setup()
must be undone by a corresponding release_region() call, as done in the
remove function.

Fixes: 1da177e ("Linux-2.6.12-rc2")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/3d607601f2c38e896b10207963c6ab499ca5c307.1741033587.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>

Author: tititiou36

drivers/i2c/busses/i2c-sis630.c

@@ -509,6 +509,8 @@ MODULE_DEVICE_TABLE(pci, sis630_ids);
 
 static int sis630_probe(struct pci_dev *dev, const struct pci_device_id *id)
 {
+	int ret;
+
 	if (sis630_setup(dev)) {
 		dev_err(&dev->dev,
 			"SIS630 compatible bus not detected, "
@@ -522,7 +524,15 @@ static int sis630_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	snprintf(sis630_adapter.name, sizeof(sis630_adapter.name),
 		 "SMBus SIS630 adapter at %04x", smbus_base + SMB_STS);
 
-	return i2c_add_adapter(&sis630_adapter);
+	ret = i2c_add_adapter(&sis630_adapter);
+	if (ret)
+		goto release_region;
+
+	return 0;
+
+release_region:
+	release_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION);
+	return ret;
 }
 
 static void sis630_remove(struct pci_dev *dev)