ncr5380: Use return instead of goto in NCR5380_select()
authorFinn Thain <fthain@telegraphics.com.au>
Sun, 3 Jan 2016 05:05:15 +0000 (16:05 +1100)
committerMartin K. Petersen <martin.petersen@oracle.com>
Thu, 7 Jan 2016 02:42:54 +0000 (21:42 -0500)
The "failed" label in NCR5380_select() is not helpful. Some failures
return 0, others -1. Use return instead of goto to improve clarity and
brevity, like atari_NCR5380.c does. Fix the relevant comments.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/NCR5380.c
drivers/scsi/atari_NCR5380.c

index b75c92967d6e741241d8a12eafd9234aa8087904..ce80a5c65eb39ebe0df2a248bcfa77731f7b545c 100644 (file)
@@ -997,16 +997,6 @@ static void NCR5380_main(struct work_struct *work)
                                         */
                                        dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, "scsi%d : main() : command for target %d lun %llu removed from issue_queue\n", instance->host_no, tmp->device->id, tmp->device->lun);
        
-                                       /*
-                                        * A successful selection is defined as one that 
-                                        * leaves us with the command connected and 
-                                        * in hostdata->connected, OR has terminated the
-                                        * command.
-                                        *
-                                        * With successful commands, we fall through
-                                        * and see if we can do an information transfer,
-                                        * with failures we will restart.
-                                        */
                                        hostdata->selecting = NULL;
                                        /* RvC: have to preset this to indicate a new command is being performed */
 
@@ -1162,9 +1152,10 @@ static irqreturn_t NCR5380_intr(int dummy, void *dev_id)
  * Inputs : instance - instantiation of the 5380 driver on which this 
  *      target lives, cmd - SCSI command to execute.
  * 
- * Returns : -1 if selection could not execute for some reason,
- *      0 if selection succeeded or failed because the target 
- *      did not respond.
+ * Returns : -1 if selection failed but should be retried.
+ *      0 if selection failed and should not be retried.
+ *      0 if selection succeeded completely (hostdata->connected == cmd).
+ *      0 if selection in progress (hostdata->selecting == cmd).
  *
  * Side effects : 
  *      If bus busy, arbitration failed, etc, NCR5380_select() will exit 
@@ -1224,7 +1215,7 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
                printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__);
                NCR5380_write(MODE_REG, MR_BASE);
                NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
-               goto failed;
+               return -1;
        }
 
        dprintk(NDEBUG_ARBITRATION, "scsi%d : arbitration complete\n", instance->host_no);
@@ -1242,7 +1233,7 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
        if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
                NCR5380_write(MODE_REG, MR_BASE);
                dprintk(NDEBUG_ARBITRATION, "scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no);
-               goto failed;
+               return -1;
        }
        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL);
 
@@ -1255,7 +1246,7 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
                NCR5380_write(MODE_REG, MR_BASE);
                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
                dprintk(NDEBUG_ARBITRATION, "scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no);
-               goto failed;
+               return -1;
        }
        /* 
         * Again, bus clear + bus settle time is 1.2us, however, this is 
@@ -1412,7 +1403,7 @@ part2:
        if(err) {
                printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__);
                NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
-               goto failed;
+               return -1;
        }
 
        dprintk(NDEBUG_SELECTION, "scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id);
@@ -1433,11 +1424,6 @@ part2:
        initialize_SCp(cmd);
 
        return 0;
-
-       /* Selection failed */
-failed:
-       return -1;
-
 }
 
 /* 
index df42610df6e4730d52456cc20c4c03b16670c3e8..6c382d1c67ff28735b69dc8ba37c90aa939805e5 100644 (file)
@@ -1382,9 +1382,9 @@ static irqreturn_t NCR5380_intr(int irq, void *dev_id)
  * Inputs : instance - instantiation of the 5380 driver on which this
  *     target lives, cmd - SCSI command to execute.
  *
- * Returns : -1 if selection could not execute for some reason,
- *     0 if selection succeeded or failed because the target
- *     did not respond.
+ * Returns : -1 if selection failed but should be retried.
+ *      0 if selection failed and should not be retried.
+ *      0 if selection succeeded completely (hostdata->connected == cmd).
  *
  * Side effects :
  *     If bus busy, arbitration failed, etc, NCR5380_select() will exit