[PATCH] I2C: i2c-piix4.c bugfix

This patch fixes a "Trying to release non-existent resource" error that
occurs during rmmod when the device isn't actually present.  It includes
some other cleanups too: error paths, whitespace, magic numbers, __devinit.

diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 1fbaac9d80d985882b5d46f91bf54d2e3269dfa5..c0aeaba29467f5b39905b600d91cf9b3f0eb979b 100644 (file)
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -68,6 +68,9 @@ struct sd {
 #define SMBSLVEVT      (0xA + piix4_smba)
 #define SMBSLVDAT      (0xC + piix4_smba)
 
+/* count for request_region */
+#define SMBIOSIZE      8
+
 /* PCI Address Constants */
 #define SMBBA          0x090
 #define SMBHSTCFG      0x0D2
@@ -112,14 +115,13 @@ MODULE_PARM_DESC(fix_hstcfg,
 
 static int piix4_transaction(void);
 
-
 static unsigned short piix4_smba = 0;
 static struct i2c_adapter piix4_adapter;
 
 /*
  * Get DMI information.
  */
-static int ibm_dmi_probe(void)
+static int __devinit ibm_dmi_probe(void)
 {
 #ifdef CONFIG_X86
        extern int is_unsafe_smbus;
@@ -129,9 +131,9 @@ static int ibm_dmi_probe(void)
 #endif
 }
 
-static int piix4_setup(struct pci_dev *PIIX4_dev, const struct pci_device_id *id)
+static int __devinit piix4_setup(struct pci_dev *PIIX4_dev,
+                               const struct pci_device_id *id)
 {
-       int error_return = 0;
        unsigned char temp;
 
        /* match up the function */
@@ -144,8 +146,7 @@ static int piix4_setup(struct pci_dev *PIIX4_dev, const struct pci_device_id *id
                dev_err(&PIIX4_dev->dev, "IBM Laptop detected; this module "
                        "may corrupt your serial eeprom! Refusing to load "
                        "module!\n");
-               error_return = -EPERM;
-               goto END;
+               return -EPERM;
        }
 
        /* Determine the address of the SMBus areas */
@@ -163,11 +164,10 @@ static int piix4_setup(struct pci_dev *PIIX4_dev, const struct pci_device_id *id
                }
        }
 
-       if (!request_region(piix4_smba, 8, "piix4-smbus")) {
+       if (!request_region(piix4_smba, SMBIOSIZE, "piix4-smbus")) {
                dev_err(&PIIX4_dev->dev, "SMB region 0x%x already in use!\n",
                        piix4_smba);
-               error_return = -ENODEV;
-               goto END;
+               return -ENODEV;
        }
 
        pci_read_config_byte(PIIX4_dev, SMBHSTCFG, &temp);
@@ -214,8 +214,9 @@ static int piix4_setup(struct pci_dev *PIIX4_dev, const struct pci_device_id *id
                } else {
                        dev_err(&PIIX4_dev->dev,
                                "Host SMBus controller not enabled!\n");
-                       error_return = -ENODEV;
-                       goto END;
+                       release_region(piix4_smba, SMBIOSIZE);
+                       piix4_smba = 0;
+                       return -ENODEV;
                }
        }
 
@@ -231,8 +232,7 @@ static int piix4_setup(struct pci_dev *PIIX4_dev, const struct pci_device_id *id
        dev_dbg(&PIIX4_dev->dev, "SMBREV = 0x%X\n", temp);
        dev_dbg(&PIIX4_dev->dev, "SMBA = 0x%X\n", piix4_smba);
 
-END:
-       return error_return;
+       return 0;
 }
 
 /* Another internally used function */
@@ -465,7 +465,8 @@ static struct pci_device_id piix4_ids[] = {
        { 0, }
 };
 
-static int __devinit piix4_probe(struct pci_dev *dev, const struct pci_device_id *id)
+static int __devinit piix4_probe(struct pci_dev *dev,
+                               const struct pci_device_id *id)
 {
        int retval;
 
@@ -479,17 +480,24 @@ static int __devinit piix4_probe(struct pci_dev *dev, const struct pci_device_id
        snprintf(piix4_adapter.name, I2C_NAME_SIZE,
                "SMBus PIIX4 adapter at %04x", piix4_smba);
 
-       retval = i2c_add_adapter(&piix4_adapter);
+       if ((retval = i2c_add_adapter(&piix4_adapter))) {
+               dev_err(&dev->dev, "Couldn't register adapter!\n");
+               release_region(piix4_smba, SMBIOSIZE);
+               piix4_smba = 0;
+       }
 
        return retval;
 }
 
 static void __devexit piix4_remove(struct pci_dev *dev)
 {
-       i2c_del_adapter(&piix4_adapter);
+       if (piix4_smba) {
+               i2c_del_adapter(&piix4_adapter);
+               release_region(piix4_smba, SMBIOSIZE);
+               piix4_smba = 0;
+       }
 }
 
-
 static struct pci_driver piix4_driver = {
        .name           = "piix4-smbus",
        .id_table       = piix4_ids,
@@ -502,15 +510,13 @@ static int __init i2c_piix4_init(void)
        return pci_module_init(&piix4_driver);
 }
 
-
 static void __exit i2c_piix4_exit(void)
 {
        pci_unregister_driver(&piix4_driver);
-       release_region(piix4_smba, 8);
 }
 
-MODULE_AUTHOR
-    ("Frodo Looijaard <frodol@dds.nl> and Philip Edelbrock <phil@netroedge.com>");
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
+               "Philip Edelbrock <phil@netroedge.com>");
 MODULE_DESCRIPTION("PIIX4 SMBus driver");
 MODULE_LICENSE("GPL");