Changeset 30

Timestamp:

12/04/98 04:49:32 (14 years ago)

Author:

phil

Message:

(Phil) OK, here is the first shot at integrating PIIX4 support in the new
lm_sensors2 project. It was *very* easy to copy-and-paste it in, so I'm
hoping that it won't include any new bugs. It builds and compiles, but
I wasn't able to test it (under 2.1.131) until we get some compatibility
problems solved. There is probably a little cleaning up to do yet, but
everything looks like it is happy. Test it under 2.0.x and let me know
what happens.

Location:

lm-sensors/trunk

Files:

• kernel/busses/i2c-piix4.c (modified) (9 diffs)
• src/piix4.c (modified) (9 diffs)

lm-sensors/trunk/kernel/busses/i2c-piix4.c

@@ -1 +1 @@
 /*
     smbus.c - A Linux module for reading sensor data.
-    Copyright (c) 1998  Frodo Looijaard <frodol@dds.nl> 
+    Copyright (c) 1998  Frodo Looijaard <frodol@dds.nl> and
+    Philip Edelbrock <phil@netroedge.com>
 
     This program is free software; you can redistribute it and/or modify
@@ -20 +21 @@
 /* Note: New PCI (non-BIOS) interface introduced in 2.1.54! */
 
+#include <linux/pci.h>
+#include <asm/io.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
@@ -25 +28 @@
 #include "smbus.h"
 #include "version.h"
+#include "compat.h"
+#include "piix4.h"
 
 static int piix4_init(void);
@@ -31 +36 @@
 static s32 piix4_access(u8 addr, char read_write,
                         u8 command, int size, union smbus_data * data);
+/* Internal functions */
+static void do_pause( unsigned int amount );
+static int SMBus_PIIX4_Transaction(void);
 
 #ifdef MODULE
@@ -40 +48 @@
 static int piix4_initialized;
 
+/* Global variables  -- At least some of these may be modified/moved later */
+static unsigned short PIIX4_smba = 0;
+static struct semaphore smbus_piix4_sem = MUTEX;
+
+
 /* Detect whether a PIIX4 can be found, and initialize it, where necessary. 
    Return -ENODEV if not found. */
 int piix4_setup(void)
 {
-  return -ENODEV;
-  /* TO BE WRITTEN! */
+  int error_return=0;
+  unsigned char temp;
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+  struct pci_dev *PIIX4_dev;
+#else
+  unsigned char PIIX4_bus, PIIX4_devfn;
+#endif
+
+  if (pci_present() == 0) {
+    printk("SMBus: Error: No PCI-bus found!\n");
+    error_return=-ENODEV;
+  } else {
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+    PIIX4_dev = pci_find_device(PCI_VENDOR_ID_INTEL, 
+                                 PCI_DEVICE_ID_INTEL_82371AB_0, NULL);
+    if(PIIX4_dev == NULL) {
+#else
+    if(pcibios_find_device(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_0, 
+                           0, &PIIX4_bus, &PIIX4_devfn)) {
+#endif
+      printk("SMBus: Error: Can't detect PIIX4!\n");
+      error_return=-ENODEV;
+    } else {
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+      /* For some reason, pci_read_config fails here sometimes! */
+      pcibios_read_config_word(PIIX4_dev->bus->number, PIIX4_dev->devfn | 3, 
+                               SMBBA, &PIIX4_smba);
+#else
+      pci_read_config_word_united(PIIX4_dev, PIIX4_bus ,PIIX4_devfn | 3,
+                                  SMBBA,&PIIX4_smba);
+#endif
+      PIIX4_smba &= 0xfff0;
+      if (check_region(PIIX4_smba, 8)) {
+        printk("PIIX4_smb region 0x%x already in use!\n",
+               PIIX4_smba);
+        error_return=-ENODEV;
+      } else {
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+        pcibios_read_config_byte(PIIX4_dev->bus->number, 
+                PIIX4_dev->devfn | 3, SMBHSTCFG, &temp);
+#else
+        pci_read_config_byte_united(PIIX4_dev, PIIX4_bus, PIIX4_devfn | 3, 
+                                    SMBHSTCFG, &temp);
+#endif
+#ifdef FORCE_PIIX4_ENABLE
+/* This should never need to be done, but has been noted that
+   many Dell machines have the SMBus interface on the PIIX4
+   disabled!? NOTE: This assumes I/O space and other allocations WERE
+   done by the Bios!  Don't complain if your hardware does weird 
+   things after enabling this. :') Check for Bios updates before
+   resorting to this.  */
+        if ((temp & 1) == 0) {
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+          pcibios_write_config_byte(PIIX4_dev->bus->number, PIIX4_dev->devfn | 3, 
+                               SMBHSTCFG, temp | 1);
+#else
+          pcibios_write_config_byte(PIIX4_bus, PIIX4_devfn | 3, SMBHSTCFG, temp | 1);
+#endif
+          printk("SMBus: WARNING: PIIX4 SMBus interface has been FORCEFULLY ENABLED!!\n");
+          /* Update configuration value */
+          pci_read_config_byte_united(PIIX4_dev, PIIX4_bus, PIIX4_devfn | 3, SMBHSTCFG, &temp);
+          /* Note: We test the bit again in the next 'if' just to be sure... */
+        }
+#endif
+        if ((temp & 1) == 0) {
+          printk("SMBUS: Error: Host SMBus controller not enabled!\n");     
+          piix4_initialized=0;
+          error_return=-ENODEV;
+        } else {
+                /* Everything is happy, let's grab the memory and set things up. */
+                request_region(PIIX4_smba, 8, "SMBus");       
+                piix4_initialized=1;
+        }
+#ifdef DEBUG
+        if ((temp & 0x0E) == 8)
+          printk("SMBUS: PIIX4 using Interrupt 9 for SMBus.\n");
+        else if ((temp & 0x0E) == 0)
+          printk("SMBUS: PIIX4 using Interrupt SMI# for SMBus.\n");
+        else 
+          printk( "SMBUS: PIIX4: Illegal Interrupt configuration (or code out of date)!\n");
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+        pcibios_read_config_byte(PIIX4_dev->bus->number, 
+                PIIX4_dev->devfn | 3, SMBREV, &temp);
+#else
+        pci_read_config_byte_united(PIIX4_dev, PIIX4_bus, PIIX4_devfn | 3, 
+                                    SMBREV, &temp);
+#endif
+        printk("SMBUS: SMBREV = 0x%X\n",temp);
+#endif
+      }
+    }
+  if (error_return)
+    printk("SMBus setup failed.\n");
+#ifdef DEBUG
+  else
+    printk("PIIX4_smba = 0x%X\n",PIIX4_smba);
+#endif
+  }
+  return error_return;
+}
+
+/* Internally used pause function */
+void do_pause( unsigned int amount )
+{
+      current->state = TASK_INTERRUPTIBLE;
+      schedule_timeout(amount);
+}
+
+/* Another internally used function */
+int SMBus_PIIX4_Transaction(void) 
+{
+  int temp;
+  int result=0;
+  int timeout=0;
+
+  /* Make sure the SMBus host is ready to start transmitting */
+  if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
+#ifdef DEBUG
+    printk("SMBus: SMBus_Read: SMBus busy (%02x). Resetting... ",temp);
+#endif
+    outb_p(temp, SMBHSTSTS);
+    if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
+#ifdef DEBUG
+      printk("Failed! (%02x)\n",temp);
+#endif
+      return -1;
+    } else {
+#ifdef DEBUG
+      printk("Successfull!\n");
+#endif
+    }
+  }
+
+  /* start the transaction by setting bit 6 */
+  outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT); 
+
+  /* Wait for a fraction of a second! (See PIIX4 docs errata) */
+  do_pause(1);
+
+  /* Poll Host_busy bit */
+  temp=inb_p(SMBHSTSTS) & 0x01;
+  while (temp & (timeout++ < MAX_TIMEOUT)) {
+    /* Wait for a while and try again*/
+    do_pause(1);
+    temp = inb_p(SMBHSTSTS) & 0x01;
+  }
+
+  /* If the SMBus is still busy, we give up */
+  if (timeout >= MAX_TIMEOUT) {
+#ifdef DEBUG
+    printk("SMBus: SMBus_Read: SMBus Timeout!\n"); 
+    result = -1;
+#endif
+  }
+
+  temp = inb_p(SMBHSTSTS);
+
+  if (temp  & 0x10) {
+    result = -1;
+#ifdef DEBUG
+    printk("SMBus error: Failed bus transaction\n");
+#endif
+  }
+
+  if (temp & 0x08) {
+    result = -1;
+    printk("SMBus error: Bus collision! SMBus may be locked until next hard reset. (sorry!)\n");
+    /* Clock stops and slave is stuck in mid-transmission */
+  }
+
+  if (temp & 0x04) {
+    result = -1;
+#ifdef DEBUG
+    printk("SMBus error: no response!\n");
+#endif
+  }
+
+  if (inb_p(SMBHSTSTS) != 0x00)
+    outb_p( inb(SMBHSTSTS), SMBHSTSTS);
+
+  if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
+#ifdef DEBUG
+    printk("SMBus error: Failed reset at end of transaction (%02x)\n",temp);
+#endif
+  }
+  return result;
 }
 
@@ -52 +251 @@
                  u8 command, int size, union smbus_data * data)
 {
-  /* TO BE WRITTEN! */
-  return -1;
-}
+  int i,len;
+
+  down(&smbus_piix4_sem);
+
+  outb_p((size & 0x1C) + (ENABLE_INT9 & 1), SMBHSTCNT);
+
+  switch(size) {
+    case SMBUS_QUICK:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      break;
+    case SMBUS_BYTE:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      if (read_write == SMBUS_WRITE)
+        outb_p(command, SMBHSTCMD);
+      break;
+    case SMBUS_BYTE_DATA:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      outb_p(command, SMBHSTCMD);
+      if (read_write == SMBUS_WRITE)
+        outb_p(data->byte,SMBHSTDAT0);
+      break;
+    case SMBUS_WORD_DATA:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      outb_p(command, SMBHSTCMD);
+      if (read_write == SMBUS_WRITE) {
+        outb_p(data->word & 0xff,SMBHSTDAT0);
+        outb_p((data->word & 0xff00) >> 8,SMBHSTDAT1);
+      }
+      break;
+    case SMBUS_BLOCK_DATA:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      outb_p(command, SMBHSTCMD);
+      if (read_write == SMBUS_WRITE) {
+        len = data->block[0];
+        if (len < 0) 
+          len = 0;
+        if (len > 32)
+          len = 32;
+        outb_p(len,SMBHSTDAT0);
+        i = inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
+        for (i = 1; i <= len; i ++)
+          outb_p(data->block[i],SMBBLKDAT);
+        break;
+      }
+  }
+
+  if (SMBus_PIIX4_Transaction()) { /* Error in transaction */ 
+    up(&smbus_piix4_sem);
+    return -1; 
+  }
+
+  if ((read_write == SMBUS_WRITE) || (size == SMBUS_QUICK)) {
+    up(&smbus_piix4_sem);
+    return 0;
+  }
+}  
 
 
@@ -62 +314 @@
   printk("piix4.o version %s (%s)\n",LM_VERSION,LM_DATE);
 #ifdef DEBUG
+/* PE- It might be good to make this a permanent part of the code! */
   if (piix4_initialized) {
     printk("piix4.o: Oops, piix4_init called a second time!\n");
@@ -97 +350 @@
       return res;
     } else
-      piix4_initialized--;
+      piix4_initialized=0;
   }
   if (piix4_initialized >= 1) {
-    /* Undo anything piix4_setup did */
-    piix4_initialized--;
+    if (piix4_initialized) {
+                release_region(PIIX4_smba, 8);
+                piix4_initialized=0;
+    }
   }
   return 0;
@@ -108 +363 @@
 #ifdef MODULE
 
-MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and Philip Edelbrock <phil@netroedge.com>");
 MODULE_DESCRIPTION("PIIX4 SMBus driver");
 

lm-sensors/trunk/src/piix4.c

@@ -1 +1 @@
 /*
     smbus.c - A Linux module for reading sensor data.
-    Copyright (c) 1998  Frodo Looijaard <frodol@dds.nl> 
+    Copyright (c) 1998  Frodo Looijaard <frodol@dds.nl> and
+    Philip Edelbrock <phil@netroedge.com>
 
     This program is free software; you can redistribute it and/or modify
@@ -20 +21 @@
 /* Note: New PCI (non-BIOS) interface introduced in 2.1.54! */
 
+#include <linux/pci.h>
+#include <asm/io.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
@@ -25 +28 @@
 #include "smbus.h"
 #include "version.h"
+#include "compat.h"
+#include "piix4.h"
 
 static int piix4_init(void);
@@ -31 +36 @@
 static s32 piix4_access(u8 addr, char read_write,
                         u8 command, int size, union smbus_data * data);
+/* Internal functions */
+static void do_pause( unsigned int amount );
+static int SMBus_PIIX4_Transaction(void);
 
 #ifdef MODULE
@@ -40 +48 @@
 static int piix4_initialized;
 
+/* Global variables  -- At least some of these may be modified/moved later */
+static unsigned short PIIX4_smba = 0;
+static struct semaphore smbus_piix4_sem = MUTEX;
+
+
 /* Detect whether a PIIX4 can be found, and initialize it, where necessary. 
    Return -ENODEV if not found. */
 int piix4_setup(void)
 {
-  return -ENODEV;
-  /* TO BE WRITTEN! */
+  int error_return=0;
+  unsigned char temp;
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+  struct pci_dev *PIIX4_dev;
+#else
+  unsigned char PIIX4_bus, PIIX4_devfn;
+#endif
+
+  if (pci_present() == 0) {
+    printk("SMBus: Error: No PCI-bus found!\n");
+    error_return=-ENODEV;
+  } else {
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+    PIIX4_dev = pci_find_device(PCI_VENDOR_ID_INTEL, 
+                                 PCI_DEVICE_ID_INTEL_82371AB_0, NULL);
+    if(PIIX4_dev == NULL) {
+#else
+    if(pcibios_find_device(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_0, 
+                           0, &PIIX4_bus, &PIIX4_devfn)) {
+#endif
+      printk("SMBus: Error: Can't detect PIIX4!\n");
+      error_return=-ENODEV;
+    } else {
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+      /* For some reason, pci_read_config fails here sometimes! */
+      pcibios_read_config_word(PIIX4_dev->bus->number, PIIX4_dev->devfn | 3, 
+                               SMBBA, &PIIX4_smba);
+#else
+      pci_read_config_word_united(PIIX4_dev, PIIX4_bus ,PIIX4_devfn | 3,
+                                  SMBBA,&PIIX4_smba);
+#endif
+      PIIX4_smba &= 0xfff0;
+      if (check_region(PIIX4_smba, 8)) {
+        printk("PIIX4_smb region 0x%x already in use!\n",
+               PIIX4_smba);
+        error_return=-ENODEV;
+      } else {
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+        pcibios_read_config_byte(PIIX4_dev->bus->number, 
+                PIIX4_dev->devfn | 3, SMBHSTCFG, &temp);
+#else
+        pci_read_config_byte_united(PIIX4_dev, PIIX4_bus, PIIX4_devfn | 3, 
+                                    SMBHSTCFG, &temp);
+#endif
+#ifdef FORCE_PIIX4_ENABLE
+/* This should never need to be done, but has been noted that
+   many Dell machines have the SMBus interface on the PIIX4
+   disabled!? NOTE: This assumes I/O space and other allocations WERE
+   done by the Bios!  Don't complain if your hardware does weird 
+   things after enabling this. :') Check for Bios updates before
+   resorting to this.  */
+        if ((temp & 1) == 0) {
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+          pcibios_write_config_byte(PIIX4_dev->bus->number, PIIX4_dev->devfn | 3, 
+                               SMBHSTCFG, temp | 1);
+#else
+          pcibios_write_config_byte(PIIX4_bus, PIIX4_devfn | 3, SMBHSTCFG, temp | 1);
+#endif
+          printk("SMBus: WARNING: PIIX4 SMBus interface has been FORCEFULLY ENABLED!!\n");
+          /* Update configuration value */
+          pci_read_config_byte_united(PIIX4_dev, PIIX4_bus, PIIX4_devfn | 3, SMBHSTCFG, &temp);
+          /* Note: We test the bit again in the next 'if' just to be sure... */
+        }
+#endif
+        if ((temp & 1) == 0) {
+          printk("SMBUS: Error: Host SMBus controller not enabled!\n");     
+          piix4_initialized=0;
+          error_return=-ENODEV;
+        } else {
+                /* Everything is happy, let's grab the memory and set things up. */
+                request_region(PIIX4_smba, 8, "SMBus");       
+                piix4_initialized=1;
+        }
+#ifdef DEBUG
+        if ((temp & 0x0E) == 8)
+          printk("SMBUS: PIIX4 using Interrupt 9 for SMBus.\n");
+        else if ((temp & 0x0E) == 0)
+          printk("SMBUS: PIIX4 using Interrupt SMI# for SMBus.\n");
+        else 
+          printk( "SMBUS: PIIX4: Illegal Interrupt configuration (or code out of date)!\n");
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,1,0))
+        pcibios_read_config_byte(PIIX4_dev->bus->number, 
+                PIIX4_dev->devfn | 3, SMBREV, &temp);
+#else
+        pci_read_config_byte_united(PIIX4_dev, PIIX4_bus, PIIX4_devfn | 3, 
+                                    SMBREV, &temp);
+#endif
+        printk("SMBUS: SMBREV = 0x%X\n",temp);
+#endif
+      }
+    }
+  if (error_return)
+    printk("SMBus setup failed.\n");
+#ifdef DEBUG
+  else
+    printk("PIIX4_smba = 0x%X\n",PIIX4_smba);
+#endif
+  }
+  return error_return;
+}
+
+/* Internally used pause function */
+void do_pause( unsigned int amount )
+{
+      current->state = TASK_INTERRUPTIBLE;
+      schedule_timeout(amount);
+}
+
+/* Another internally used function */
+int SMBus_PIIX4_Transaction(void) 
+{
+  int temp;
+  int result=0;
+  int timeout=0;
+
+  /* Make sure the SMBus host is ready to start transmitting */
+  if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
+#ifdef DEBUG
+    printk("SMBus: SMBus_Read: SMBus busy (%02x). Resetting... ",temp);
+#endif
+    outb_p(temp, SMBHSTSTS);
+    if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
+#ifdef DEBUG
+      printk("Failed! (%02x)\n",temp);
+#endif
+      return -1;
+    } else {
+#ifdef DEBUG
+      printk("Successfull!\n");
+#endif
+    }
+  }
+
+  /* start the transaction by setting bit 6 */
+  outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT); 
+
+  /* Wait for a fraction of a second! (See PIIX4 docs errata) */
+  do_pause(1);
+
+  /* Poll Host_busy bit */
+  temp=inb_p(SMBHSTSTS) & 0x01;
+  while (temp & (timeout++ < MAX_TIMEOUT)) {
+    /* Wait for a while and try again*/
+    do_pause(1);
+    temp = inb_p(SMBHSTSTS) & 0x01;
+  }
+
+  /* If the SMBus is still busy, we give up */
+  if (timeout >= MAX_TIMEOUT) {
+#ifdef DEBUG
+    printk("SMBus: SMBus_Read: SMBus Timeout!\n"); 
+    result = -1;
+#endif
+  }
+
+  temp = inb_p(SMBHSTSTS);
+
+  if (temp  & 0x10) {
+    result = -1;
+#ifdef DEBUG
+    printk("SMBus error: Failed bus transaction\n");
+#endif
+  }
+
+  if (temp & 0x08) {
+    result = -1;
+    printk("SMBus error: Bus collision! SMBus may be locked until next hard reset. (sorry!)\n");
+    /* Clock stops and slave is stuck in mid-transmission */
+  }
+
+  if (temp & 0x04) {
+    result = -1;
+#ifdef DEBUG
+    printk("SMBus error: no response!\n");
+#endif
+  }
+
+  if (inb_p(SMBHSTSTS) != 0x00)
+    outb_p( inb(SMBHSTSTS), SMBHSTSTS);
+
+  if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
+#ifdef DEBUG
+    printk("SMBus error: Failed reset at end of transaction (%02x)\n",temp);
+#endif
+  }
+  return result;
 }
 
@@ -52 +251 @@
                  u8 command, int size, union smbus_data * data)
 {
-  /* TO BE WRITTEN! */
-  return -1;
-}
+  int i,len;
+
+  down(&smbus_piix4_sem);
+
+  outb_p((size & 0x1C) + (ENABLE_INT9 & 1), SMBHSTCNT);
+
+  switch(size) {
+    case SMBUS_QUICK:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      break;
+    case SMBUS_BYTE:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      if (read_write == SMBUS_WRITE)
+        outb_p(command, SMBHSTCMD);
+      break;
+    case SMBUS_BYTE_DATA:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      outb_p(command, SMBHSTCMD);
+      if (read_write == SMBUS_WRITE)
+        outb_p(data->byte,SMBHSTDAT0);
+      break;
+    case SMBUS_WORD_DATA:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      outb_p(command, SMBHSTCMD);
+      if (read_write == SMBUS_WRITE) {
+        outb_p(data->word & 0xff,SMBHSTDAT0);
+        outb_p((data->word & 0xff00) >> 8,SMBHSTDAT1);
+      }
+      break;
+    case SMBUS_BLOCK_DATA:
+      outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD);
+      outb_p(command, SMBHSTCMD);
+      if (read_write == SMBUS_WRITE) {
+        len = data->block[0];
+        if (len < 0) 
+          len = 0;
+        if (len > 32)
+          len = 32;
+        outb_p(len,SMBHSTDAT0);
+        i = inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
+        for (i = 1; i <= len; i ++)
+          outb_p(data->block[i],SMBBLKDAT);
+        break;
+      }
+  }
+
+  if (SMBus_PIIX4_Transaction()) { /* Error in transaction */ 
+    up(&smbus_piix4_sem);
+    return -1; 
+  }
+
+  if ((read_write == SMBUS_WRITE) || (size == SMBUS_QUICK)) {
+    up(&smbus_piix4_sem);
+    return 0;
+  }
+}  
 
 
@@ -62 +314 @@
   printk("piix4.o version %s (%s)\n",LM_VERSION,LM_DATE);
 #ifdef DEBUG
+/* PE- It might be good to make this a permanent part of the code! */
   if (piix4_initialized) {
     printk("piix4.o: Oops, piix4_init called a second time!\n");
@@ -97 +350 @@
       return res;
     } else
-      piix4_initialized--;
+      piix4_initialized=0;
   }
   if (piix4_initialized >= 1) {
-    /* Undo anything piix4_setup did */
-    piix4_initialized--;
+    if (piix4_initialized) {
+                release_region(PIIX4_smba, 8);
+                piix4_initialized=0;
+    }
   }
   return 0;
@@ -108 +363 @@
 #ifdef MODULE
 
-MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and Philip Edelbrock <phil@netroedge.com>");
 MODULE_DESCRIPTION("PIIX4 SMBus driver");