[PATCH] i2c-viapro: Code cleanups

Cleanups to the i2c-viapro driver:
* Kill unused defines.
* Kill interrupt-related code, as the driver doesn't use interrupts.
* Fix broken comments (some copied from i2c-piix4.)
* Centralize the unsupported command error case in vt596_access.
  That way we'll catch all unsupported commands, not only
  I2C_SMBUS_PROC_CALL.
* Refactor some code.
* Convert some dev_dbg into dev_err. Errors better be reported even in
  non-debug mode.
* Do not verify that the final reset succeeded. It'll be checked at
  the beginning of the next transaction anyway.
* Use the driver name to reserve the I/O region.
* Do not print the contents of the SMBREV register, it reads 0 on all
  chips I've seen so far.
* Some other minor fixes all over the place.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

 drivers/i2c/busses/i2c-viapro.c |  122 +++++++++++++---------------------------
 1 file changed, 41 insertions(+), 81 deletions(-)

1 files changed, 41 insertions, 81 deletions

diff --git a/drivers/i2c/busses/i2c-viapro.c b/drivers/i2c/busses/i2c-viapro.c
index b420e752b1dc..5cf8fe182806 100644
--- a/drivers/i2c/busses/i2c-viapro.c
+++ b/drivers/i2c/busses/i2c-viapro.c
@@ -39,7 +39,6 @@
 #include <linux/pci.h>
 #include <linux/kernel.h>
 #include <linux/stddef.h>
-#include <linux/sched.h>
 #include <linux/ioport.h>
 #include <linux/i2c.h>
 #include <linux/init.h>
@@ -54,34 +53,22 @@ static struct pci_dev *vt596_pdev;
 /* SMBus address offsets */
 static unsigned short vt596_smba;
 #define SMBHSTSTS       (vt596_smba + 0)
-#define SMBHSLVSTS      (vt596_smba + 1)
 #define SMBHSTCNT       (vt596_smba + 2)
 #define SMBHSTCMD       (vt596_smba + 3)
 #define SMBHSTADD       (vt596_smba + 4)
 #define SMBHSTDAT0      (vt596_smba + 5)
 #define SMBHSTDAT1      (vt596_smba + 6)
 #define SMBBLKDAT       (vt596_smba + 7)
-#define SMBSLVCNT       (vt596_smba + 8)
-#define SMBSHDWCMD      (vt596_smba + 9)
-#define SMBSLVEVT       (vt596_smba + 0xA)
-#define SMBSLVDAT       (vt596_smba + 0xC)
 
 /* PCI Address Constants */
 
 /* SMBus data in configuration space can be found in two places,
    We try to select the better one */
 
-static unsigned short smb_cf_hstcfg = 0xD2;
-
-#define SMBHSTCFG       (smb_cf_hstcfg)
-#define SMBSLVC         (smb_cf_hstcfg + 1)
-#define SMBSHDW1        (smb_cf_hstcfg + 2)
-#define SMBSHDW2        (smb_cf_hstcfg + 3)
-#define SMBREV          (smb_cf_hstcfg + 4)
+static unsigned short SMBHSTCFG = 0xD2;
 
 /* Other settings */
 #define MAX_TIMEOUT     500
-#define ENABLE_INT9     0
 
 /* VT82C596 constants */
 #define VT596_QUICK             0x00
@@ -107,12 +94,13 @@ MODULE_PARM_DESC(force_addr,
                  "EXTREMELY DANGEROUS!");
 
 
+static struct pci_driver vt596_driver;
 static struct i2c_adapter vt596_adapter;
 
 #define FEATURE_I2CBLOCK        (1<<0)
 static unsigned int vt596_features;
 
-/* Another internally used function */
+/* Return -1 on error, 0 on success */
 static int vt596_transaction(void)
 {
         int temp;
@@ -127,23 +115,21 @@ static int vt596_transaction(void)
         /* Make sure the SMBus host is ready to start transmitting */
         if ((temp = inb_p(SMBHSTSTS)) & 0x1F) {
                 dev_dbg(&vt596_adapter.dev, "SMBus busy (0x%02x). "
-                        "Resetting...\n", temp);
+                        "Resetting... ", temp);
 
                 outb_p(temp, SMBHSTSTS);
                 if ((temp = inb_p(SMBHSTSTS)) & 0x1F) {
-                        dev_dbg(&vt596_adapter.dev, "Failed! (0x%02x)\n", temp);
-
+                        printk("Failed! (0x%02x)\n", temp);
                         return -1;
                 } else {
-                        dev_dbg(&vt596_adapter.dev, "Successfull!\n");
+                        printk("Successful!\n");
                 }
         }
 
-        /* start the transaction by setting bit 6 */
-        outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT);
+        /* Start the transaction by setting bit 6 */
+        outb_p(inb(SMBHSTCNT) | 0x40, SMBHSTCNT);
 
-        /* We will always wait for a fraction of a second!
-           I don't know if VIA needs this, Intel did  */
+        /* We will always wait for a fraction of a second */
         do {
                 msleep(1);
                 temp = inb_p(SMBHSTSTS);
@@ -152,33 +138,32 @@ static int vt596_transaction(void)
         /* If the SMBus is still busy, we give up */
         if (timeout >= MAX_TIMEOUT) {
                 result = -1;
-                dev_dbg(&vt596_adapter.dev, "SMBus Timeout!\n");
+                dev_err(&vt596_adapter.dev, "SMBus timeout!\n");
         }
 
         if (temp & 0x10) {
                 result = -1;
-                dev_dbg(&vt596_adapter.dev, "Error: Failed bus transaction\n");
+                dev_err(&vt596_adapter.dev, "Transaction failed (0x%02x)\n",
+                        inb_p(SMBHSTCNT) & 0x3C);
         }
 
         if (temp & 0x08) {
                 result = -1;
-                dev_info(&vt596_adapter.dev, "Bus collision! SMBus may be "
-                        "locked until next hard\nreset. (sorry!)\n");
-                /* Clock stops and slave is stuck in mid-transmission */
+                dev_err(&vt596_adapter.dev, "SMBus collision!\n");
         }
 
         if (temp & 0x04) {
                 result = -1;
-                dev_dbg(&vt596_adapter.dev, "Error: no response!\n");
+                /* Quick commands are used to probe for chips, so
+                   errors are expected, and we don't want to frighten the
+                   user. */
+                if ((inb_p(SMBHSTCNT) & 0x3C) != VT596_QUICK)
+                        dev_err(&vt596_adapter.dev, "Transaction error!\n");
         }
 
-        if ((temp = inb_p(SMBHSTSTS)) & 0x1F) {
+        /* Resetting status register */
+        if (temp & 0x1F)
                 outb_p(temp, SMBHSTSTS);
-                if ((temp = inb_p(SMBHSTSTS)) & 0x1F) {
-                        dev_warn(&vt596_adapter.dev, "Failed reset at end "
-                                 "of transaction (%02x)\n", temp);
-                }
-        }
 
         dev_dbg(&vt596_adapter.dev, "Transaction (post): CNT=%02x, CMD=%02x, "
                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
@@ -188,41 +173,29 @@ static int vt596_transaction(void)
         return result;
 }
 
-/* Return -1 on error. */
+/* Return -1 on error, 0 on success */
 static s32 vt596_access(struct i2c_adapter *adap, u16 addr,
                 unsigned short flags, char read_write, u8 command,
                 int size, union i2c_smbus_data *data)
 {
-        int i, len;
+        int i;
 
         switch (size) {
-        case I2C_SMBUS_PROC_CALL:
-                dev_info(&vt596_adapter.dev,
-                         "I2C_SMBUS_PROC_CALL not supported!\n");
-                return -1;
         case I2C_SMBUS_QUICK:
-                outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-                       SMBHSTADD);
                 size = VT596_QUICK;
                 break;
         case I2C_SMBUS_BYTE:
-                outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-                       SMBHSTADD);
                 if (read_write == I2C_SMBUS_WRITE)
                         outb_p(command, SMBHSTCMD);
                 size = VT596_BYTE;
                 break;
         case I2C_SMBUS_BYTE_DATA:
-                outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-                       SMBHSTADD);
                 outb_p(command, SMBHSTCMD);
                 if (read_write == I2C_SMBUS_WRITE)
                         outb_p(data->byte, SMBHSTDAT0);
                 size = VT596_BYTE_DATA;
                 break;
         case I2C_SMBUS_WORD_DATA:
-                outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-                       SMBHSTADD);
                 outb_p(command, SMBHSTCMD);
                 if (read_write == I2C_SMBUS_WRITE) {
                         outb_p(data->word & 0xff, SMBHSTDAT0);
@@ -232,31 +205,30 @@ static s32 vt596_access(struct i2c_adapter *adap, u16 addr,
                 break;
         case I2C_SMBUS_I2C_BLOCK_DATA:
                 if (!(vt596_features & FEATURE_I2CBLOCK))
-                        return -1;
+                        goto exit_unsupported;
                 if (read_write == I2C_SMBUS_READ)
                         outb_p(I2C_SMBUS_BLOCK_MAX, SMBHSTDAT0);
                 /* Fall through */
         case I2C_SMBUS_BLOCK_DATA:
-                outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-                       SMBHSTADD);
                 outb_p(command, SMBHSTCMD);
                 if (read_write == I2C_SMBUS_WRITE) {
-                        len = data->block[0];
-                        if (len < 0)
-                                len = 0;
+                        u8 len = data->block[0];
                         if (len > I2C_SMBUS_BLOCK_MAX)
                                 len = I2C_SMBUS_BLOCK_MAX;
                         outb_p(len, SMBHSTDAT0);
-                        i = inb_p(SMBHSTCNT);   /* Reset SMBBLKDAT */
+                        inb_p(SMBHSTCNT);       /* Reset SMBBLKDAT */
                         for (i = 1; i <= len; i++)
                                 outb_p(data->block[i], SMBBLKDAT);
                 }
                 size = (size == I2C_SMBUS_I2C_BLOCK_DATA) ?
                        VT596_I2C_BLOCK_DATA : VT596_BLOCK_DATA;
                 break;
+        default:
+                goto exit_unsupported;
         }
 
-        outb_p((size & 0x3C) + (ENABLE_INT9 & 1), SMBHSTCNT);
+        outb_p(((addr & 0x7f) << 1) | read_write, SMBHSTADD);
+        outb_p((size & 0x3C), SMBHSTCNT);
 
         if (vt596_transaction()) /* Error in transaction */
                 return -1;
@@ -266,12 +238,6 @@ static s32 vt596_access(struct i2c_adapter *adap, u16 addr,
 
         switch (size) {
         case VT596_BYTE:
-                /* Where is the result put? I assume here it is in
-                 * SMBHSTDAT0 but it might just as well be in the
-                 * SMBHSTCMD. No clue in the docs
-                 */
-                data->byte = inb_p(SMBHSTDAT0);
-                break;
         case VT596_BYTE_DATA:
                 data->byte = inb_p(SMBHSTDAT0);
                 break;
@@ -283,12 +249,17 @@ static s32 vt596_access(struct i2c_adapter *adap, u16 addr,
                 data->block[0] = inb_p(SMBHSTDAT0);
                 if (data->block[0] > I2C_SMBUS_BLOCK_MAX)
                         data->block[0] = I2C_SMBUS_BLOCK_MAX;
-                i = inb_p(SMBHSTCNT);   /* Reset SMBBLKDAT */
+                inb_p(SMBHSTCNT);       /* Reset SMBBLKDAT */
                 for (i = 1; i <= data->block[0]; i++)
                         data->block[i] = inb_p(SMBBLKDAT);
                 break;
         }
         return 0;
+
+exit_unsupported:
+        dev_warn(&vt596_adapter.dev, "Unsupported command invoked! (0x%02x)\n",
+                 size);
+        return -1;
 }
 
 static u32 vt596_func(struct i2c_adapter *adapter)
@@ -311,7 +282,6 @@ static struct i2c_adapter vt596_adapter = {
         .owner          = THIS_MODULE,
         .class          = I2C_CLASS_HWMON,
         .algo           = &smbus_algorithm,
-        .name           = "unset",
 };
 
 static int __devinit vt596_probe(struct pci_dev *pdev,
@@ -328,12 +298,12 @@ static int __devinit vt596_probe(struct pci_dev *pdev,
         }
 
         if ((pci_read_config_word(pdev, id->driver_data, &vt596_smba)) ||
-            !(vt596_smba & 0x1)) {
+            !(vt596_smba & 0x0001)) {
                 /* try 2nd address and config reg. for 596 */
                 if (id->device == PCI_DEVICE_ID_VIA_82C596_3 &&
                     !pci_read_config_word(pdev, SMBBA2, &vt596_smba) &&
-                    (vt596_smba & 0x1)) {
-                        smb_cf_hstcfg = 0x84;
+                    (vt596_smba & 0x0001)) {
+                        SMBHSTCFG = 0x84;
                 } else {
                         /* no matches at all */
                         dev_err(&pdev->dev, "Cannot configure "
@@ -351,7 +321,7 @@ static int __devinit vt596_probe(struct pci_dev *pdev,
         }
 
 found:
-        if (!request_region(vt596_smba, 8, "viapro-smbus")) {
+        if (!request_region(vt596_smba, 8, vt596_driver.name)) {
                 dev_err(&pdev->dev, "SMBus region 0x%x already in use!\n",
                         vt596_smba);
                 return -ENODEV;
@@ -366,7 +336,7 @@ found:
                 pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01);
                 dev_warn(&pdev->dev, "WARNING: SMBus interface set to new "
                          "address 0x%04x!\n", vt596_smba);
-        } else if ((temp & 1) == 0) {
+        } else if (!(temp & 0x01)) {
                 if (force) {
                         /* NOTE: This assumes I/O space and other allocations
                          * WERE done by the Bios!  Don't complain if your
@@ -374,7 +344,7 @@ found:
                          * :') Check for Bios updates before resorting to
                          * this.
                          */
-                        pci_write_config_byte(pdev, SMBHSTCFG, temp | 1);
+                        pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01);
                         dev_info(&pdev->dev, "Enabling SMBus device\n");
                 } else {
                         dev_err(&pdev->dev, "SMBUS: Error: Host SMBus "
@@ -384,16 +354,6 @@ found:
                 }
         }
 
-        if ((temp & 0x0E) == 8)
-                dev_dbg(&pdev->dev, "using Interrupt 9 for SMBus.\n");
-        else if ((temp & 0x0E) == 0)
-                dev_dbg(&pdev->dev, "using Interrupt SMI# for SMBus.\n");
-        else
-                dev_dbg(&pdev->dev, "Illegal Interrupt configuration "
-                        "(or code out of date)!\n");
-
-        pci_read_config_byte(pdev, SMBREV, &temp);
-        dev_dbg(&pdev->dev, "SMBREV = 0x%X\n", temp);
         dev_dbg(&pdev->dev, "VT596_smba = 0x%X\n", vt596_smba);
 
         switch (pdev->device) {