i2c: ali1535: Fix an error handling path in ali1535_probe()

If i2c_add_adapter() fails, the request_region() call in ali1535_setup()
must be undone by a corresponding release_region() call, as done in the
remove function.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Christophe JAILLET <[e-mail]>
Signed-off-by: Andi Shyti <[e-mail]>
Link: https://lore.kernel.org/r/0daf63d7a2[e-mail]

drivers/i2c/busses/i2c-ali1535.c

···
 
 static int ali1535_probe(struct pci_dev *dev, const struct pci_device_id *id)
 {
+	int ret;
+
 	if (ali1535_setup(dev)) {
 		dev_warn(&dev->dev,
 			"ALI1535 not detected, module not inserted.\n");
···
 
 	snprintf(ali1535_adapter.name, sizeof(ali1535_adapter.name),
 		"SMBus ALI1535 adapter at %04x", ali1535_offset);
-	return i2c_add_adapter(&ali1535_adapter);
+	ret = i2c_add_adapter(&ali1535_adapter);
+	if (ret)
+		goto release_region;
+
+	return 0;
+
+release_region:
+	release_region(ali1535_smba, ALI1535_SMB_IOSIZE);
+	return ret;
 }
 
 static void ali1535_remove(struct pci_dev *dev)