Changeset 1190 for lm-sensors/trunk/kernel/busses/i2c-amd756.c

Timestamp:

09/19/01 19:57:11 (12 years ago)

Author:

mds

Message:

Loop waiting for un-busy at start of transaction.

Fail and printk if still busy.
Fail and printk if completion timeout at end of transaction.
Reduce timeout from 5 sec to 1 sec.

Files:

• lm-sensors/trunk/kernel/busses/i2c-amd756.c (modified) (11 diffs)

lm-sensors/trunk/kernel/busses/i2c-amd756.c

@@ -80 +80 @@
 
 /* Other settings */
-#define MAX_TIMEOUT 500
+#define MAX_TIMEOUT 100
 
 /* AMD756 constants */
@@ -145 +145 @@
 int amd756_setup(void)
 {
-        int error_return = 0;
         unsigned char temp;
         int *num = supported;
         struct pci_dev *AMD756_dev = NULL;
 
-        /* First check whether we can access PCI at all */
         if (pci_present() == 0) {
                 printk("i2c-amd756.o: Error: No PCI-bus found!\n");
@@ -178 +176 @@
         if ((temp & 128) == 0) {
                 printk
-                    ("SMBUS: Error: Host SMBus controller I/O not enabled!\n");
+                  ("i2c-amd756.o: Error: SMBus controller I/O not enabled!\n");
                 return(-ENODEV);
         }
@@ -190 +188 @@
         if (check_region(amd756_smba, SMB_IOSIZE)) {
                 printk
-                    ("i2c-amd756.o: AMD756_smb region 0x%x already in use!\n",
+                    ("i2c-amd756.o: SMB region 0x%x already in use!\n",
                      amd756_smba);
                 return(-ENODEV);
@@ -199 +197 @@
 
 #ifdef DEBUG
-        /*
-           if ((temp & 0x0E) == 8)
-           printk("i2c-amd756.o: AMD756 using Interrupt 9 for SMBus.\n");
-           else if ((temp & 0x0E) == 0)
-           printk("i2c-amd756.o: AMD756 using Interrupt SMI# for SMBus.\n");
-           else 
-           printk("i2c-amd756.o: AMD756: Illegal Interrupt configuration (or code out "
-           "of date)!\n");
-         */
-
         pci_read_config_byte(AMD756_dev, SMBREV, &temp);
         printk("i2c-amd756.o: SMBREV = 0x%X\n", temp);
@@ -236 +224 @@
 #define GS_HCYC_STS (1 << 4)
 #define GS_TO_STS (1 << 5)
+#define GS_SMB_STS (1 << 11)
 
 #define GS_CLEAR_STS (GS_ABRT_STS | GS_COL_STS | GS_PRERR_STS | \
@@ -243 +232 @@
 #define GE_HOST_STC (1 << 3)
 
-/* Another internally used function */
 int amd756_transaction(void)
 {
@@ -258 +246 @@
 
         /* Make sure the SMBus host is ready to start transmitting */
-        /* TODO: What about SM_BSY? */
-        if (((temp = inw_p(SMB_GLOBAL_STATUS)) & GS_HST_STS) != 0x00) {
-#ifdef DEBUG
-                printk
-                    ("i2c-amd756.o: SMBus busy (%04x). Resetting (NOT)... \n",
-                     temp);
-#endif
-                /* TODO: How to reset the AMD?
-                   outb_p(temp, SMBHSTSTS);
-                 */
-                if (((temp = inw_p(SMB_GLOBAL_STATUS)) & GS_HST_STS) !=
-                    0x00) {
-#ifdef DEBUG
-                        printk("i2c-amd756.o: Failed! (%04x)\n", temp);
-#endif
-                        return -1;
-                } else {
-#ifdef DEBUG
-                        printk("i2c-amd756.o: Successfull!\n");
-#endif
+        if ((temp = inw_p(SMB_GLOBAL_STATUS)) & (GS_HST_STS | GS_SMB_STS)) {
+#ifdef DEBUG
+                printk
+                    ("i2c-amd756.o: SMBus busy (%04x). Waiting... \n", temp);
+#endif
+                do {
+                        amd756_do_pause(1);
+                        temp = inw_p(SMB_GLOBAL_STATUS);
+                } while ((temp & (GS_HST_STS | GS_SMB_STS)) &&
+                         (timeout++ < MAX_TIMEOUT));
+                /* If the SMBus is still busy, we give up */
+                if (timeout >= MAX_TIMEOUT) {
+                        printk("i2c-amd756.o: Busy wait timeout! (%04x)\n",
+                               temp);
+                        return(-1);
                 }
-        }
-
-        /* start the transaction by setting bit 6 */
+                timeout = 0;
+        }
+
+        /* start the transaction by setting the start bit */
         outw_p(inw(SMB_GLOBAL_ENABLE) | GE_HOST_STC, SMB_GLOBAL_ENABLE);
 
@@ -292 +276 @@
         /* If the SMBus is still busy, we give up */
         if (timeout >= MAX_TIMEOUT) {
-#ifdef DEBUG
-                printk("i2c-amd756.o: SMBus explicit timeout!\n");
-                result = -1;
-#endif
+                printk("i2c-amd756.o: Completion timeout!\n");
+                return(-1);
         }
 
@@ -301 +283 @@
                 result = -1;
 #ifdef DEBUG
-                printk("i2c-amd756.o: SMBus Protocol error!\n");
+                printk("i2c-amd756.o: SMBus Protocol error (no response)!\n");
 #endif
         }
@@ -325 +307 @@
         outw_p(GS_CLEAR_STS, SMB_GLOBAL_STATUS);
 
+#ifdef DEBUG
         if (((temp = inw_p(SMB_GLOBAL_STATUS)) & GS_CLEAR_STS) != 0x00) {
-#ifdef DEBUG
                 printk
                     ("i2c-amd756.o: Failed reset at end of transaction (%04x)\n",
                      temp);
-#endif
-        }
-#ifdef DEBUG
+        }
         printk
             ("i2c-amd756.o: Transaction (post): GS=%04x, GE=%04x, ADD=%04x, DAT=%04x\n",