i2c: Fix error value returned by several bus drivers

When adding checks for ACPI resource conflicts to many bus drivers,
not enough attention was paid to the error paths, and for several
drivers this causes 0 to be returned on error in some cases. Fix this
by properly returning a non-zero value on every error.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@kernel.org

drivers/i2c/busses/i2c-ali1535.c

@@ -140,7 +140,7 @@ static unsigned short ali1535_smba;
    defined to make the transition easier. */
 static int __devinit ali1535_setup(struct pci_dev *dev)
 {
-	int retval = -ENODEV;
+	int retval;
 	unsigned char temp;
 
 	/* Check the following things:
@@ -155,6 +155,7 @@ static int __devinit ali1535_setup(struct pci_dev *dev)
 	if (ali1535_smba == 0) {
 		dev_warn(&dev->dev,
 			"ALI1535_smb region uninitialized - upgrade BIOS?\n");
+		retval = -ENODEV;
 		goto exit;
 	}
 
@@ -167,6 +168,7 @@ static int __devinit ali1535_setup(struct pci_dev *dev)
 			    ali1535_driver.name)) {
 		dev_err(&dev->dev, "ALI1535_smb region 0x%x already in use!\n",
 			ali1535_smba);
+		retval = -EBUSY;
 		goto exit;
 	}
 
@@ -174,6 +176,7 @@ static int __devinit ali1535_setup(struct pci_dev *dev)
 	pci_read_config_byte(dev, SMBCFG, &temp);
 	if ((temp & ALI1535_SMBIO_EN) == 0) {
 		dev_err(&dev->dev, "SMB device not enabled - upgrade BIOS?\n");
+		retval = -ENODEV;
 		goto exit_free;
 	}
 
@@ -181,6 +184,7 @@ static int __devinit ali1535_setup(struct pci_dev *dev)
 	pci_read_config_byte(dev, SMBHSTCFG, &temp);
 	if ((temp & 1) == 0) {
 		dev_err(&dev->dev, "SMBus controller not enabled - upgrade BIOS?\n");
+		retval = -ENODEV;
 		goto exit_free;
 	}
 
@@ -198,12 +202,11 @@ static int __devinit ali1535_setup(struct pci_dev *dev)
 	dev_dbg(&dev->dev, "SMBREV = 0x%X\n", temp);
 	dev_dbg(&dev->dev, "ALI1535_smba = 0x%X\n", ali1535_smba);
 
-	retval = 0;
-exit:
-	return retval;
+	return 0;
 
 exit_free:
 	release_region(ali1535_smba, ALI1535_SMB_IOSIZE);
+exit:
 	return retval;
 }
 

drivers/i2c/busses/i2c-nforce2.c

@@ -356,7 +356,7 @@ static int __devinit nforce2_probe_smb (struct pci_dev *dev, int bar,
 	error = acpi_check_region(smbus->base, smbus->size,
 				  nforce2_driver.name);
 	if (error)
-		return -1;
+		return error;
 
 	if (!request_region(smbus->base, smbus->size, nforce2_driver.name)) {
 		dev_err(&smbus->adapter.dev, "Error requesting region %02x .. %02X for %s\n",

drivers/i2c/busses/i2c-sis5595.c

@@ -147,7 +147,7 @@ static int __devinit sis5595_setup(struct pci_dev *SIS5595_dev)
 	u16 a;
 	u8 val;
 	int *i;
-	int retval = -ENODEV;
+	int retval;
 
 	/* Look for imposters */
 	for (i = blacklist; *i != 0; i++) {
@@ -223,7 +223,7 @@ static int __devinit sis5595_setup(struct pci_dev *SIS5595_dev)
 
 error:
 	release_region(sis5595_base + SMB_INDEX, 2);
-	return retval;
+	return -ENODEV;
 }
 
 static int sis5595_transaction(struct i2c_adapter *adap)

drivers/i2c/busses/i2c-sis630.c

@@ -393,7 +393,7 @@ static int __devinit sis630_setup(struct pci_dev *sis630_dev)
 {
 	unsigned char b;
 	struct pci_dev *dummy = NULL;
-	int retval = -ENODEV, i;
+	int retval, i;
 
 	/* check for supported SiS devices */
 	for (i=0; supported[i] > 0 ; i++) {
@@ -418,18 +418,21 @@ static int __devinit sis630_setup(struct pci_dev *sis630_dev)
 	*/
 	if (pci_read_config_byte(sis630_dev, SIS630_BIOS_CTL_REG,&b)) {
 		dev_err(&sis630_dev->dev, "Error: Can't read bios ctl reg\n");
+		retval = -ENODEV;
 		goto exit;
 	}
 	/* if ACPI already enabled , do nothing */
 	if (!(b & 0x80) &&
 	    pci_write_config_byte(sis630_dev, SIS630_BIOS_CTL_REG, b | 0x80)) {
 		dev_err(&sis630_dev->dev, "Error: Can't enable ACPI\n");
+		retval = -ENODEV;
 		goto exit;
 	}
 
 	/* Determine the ACPI base address */
 	if (pci_read_config_word(sis630_dev,SIS630_ACPI_BASE_REG,&acpi_base)) {
 		dev_err(&sis630_dev->dev, "Error: Can't determine ACPI base address\n");
+		retval = -ENODEV;
 		goto exit;
 	}
 
@@ -445,6 +448,7 @@ static int __devinit sis630_setup(struct pci_dev *sis630_dev)
 			    sis630_driver.name)) {
 		dev_err(&sis630_dev->dev, "SMBus registers 0x%04x-0x%04x already "
 			"in use!\n", acpi_base + SMB_STS, acpi_base + SMB_SAA);
+		retval = -EBUSY;
 		goto exit;
 	}
 

drivers/i2c/busses/i2c-viapro.c

@@ -324,7 +324,7 @@ static int __devinit vt596_probe(struct pci_dev *pdev,
 				 const struct pci_device_id *id)
 {
 	unsigned char temp;
-	int error = -ENODEV;
+	int error;
 
 	/* Determine the address of the SMBus areas */
 	if (force_addr) {
@@ -390,6 +390,7 @@ static int __devinit vt596_probe(struct pci_dev *pdev,
 			dev_err(&pdev->dev, "SMBUS: Error: Host SMBus "
 				"controller not enabled! - upgrade BIOS or "
 				"use force=1\n");
+			error = -ENODEV;
 			goto release_region;
 		}
 	}
@@ -422,9 +423,11 @@ static int __devinit vt596_probe(struct pci_dev *pdev,
 		 "SMBus Via Pro adapter at %04x", vt596_smba);
 
 	vt596_pdev = pci_dev_get(pdev);
-	if (i2c_add_adapter(&vt596_adapter)) {
+	error = i2c_add_adapter(&vt596_adapter);
+	if (error) {
 		pci_dev_put(vt596_pdev);
 		vt596_pdev = NULL;
+		goto release_region;
 	}
 
 	/* Always return failure here.  This is to allow other drivers to bind