Configuring core drivers using macros like this one prevents re-unifying
the core driver forks, and prevents implementing the core driver as a
library or a platform driver.

The UNSAFE macro in particular is a poor workaround for the problem of
interrupt latency. Releasing the locks complicates things because then we
would have to handle the possibility of EH handler invocation during a
PDMA transfer.

The comments say that instead of using this macro, "you're going to be
better off twiddling with transfersize". I agree. Remove this stuff.

Signed-off-by: Finn Thain <fth...@telegraphics.com.au>

---
 drivers/scsi/NCR5380.c |   15 ---------------
 drivers/scsi/dtc.c     |    2 --
 drivers/scsi/pas16.c   |    1 -
 3 files changed, 18 deletions(-)

Index: linux/drivers/scsi/NCR5380.c
===================================================================
--- linux.orig/drivers/scsi/NCR5380.c   2015-11-18 19:33:49.000000000 +1100
+++ linux/drivers/scsi/NCR5380.c        2015-11-18 19:33:52.000000000 +1100
@@ -195,12 +195,6 @@
  *      rely on phase mismatch and EOP interrupts to determine end 
  *      of phase.
  *
- * UNSAFE - leave interrupts enabled during pseudo-DMA transfers.  You
- *          only really want to use this if you're having a problem with
- *          dropped characters during high speed communications, and even
- *          then, you're going to be better off twiddling with transfersize
- *          in the high level code.
- *
  * Defaults for these will be provided although the user may want to adjust 
  * these to allocate CPU resources to the SCSI driver or "real" code.
  * 
@@ -563,9 +557,6 @@ static void prepare_info(struct Scsi_Hos
 #ifdef PSEUDO_DMA
                 "PSEUDO_DMA "
 #endif
-#ifdef UNSAFE
-                "UNSAFE "
-#endif
                 "");
 }
 
@@ -1575,9 +1566,6 @@ static int NCR5380_transfer_dma(struct S
         * before the setting of DMA mode to after transfer of the last byte.
         */
 
-#if defined(PSEUDO_DMA) && defined(UNSAFE)
-       spin_unlock_irq(instance->host_lock);
-#endif
        /* KLL May need eop and parity in 53c400 */
        if (hostdata->flags & FLAG_NCR53C400)
                NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE |
@@ -1786,9 +1774,6 @@ static int NCR5380_transfer_dma(struct S
        *data = d + c;
        *count = 0;
        *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
-#if defined(PSEUDO_DMA) && defined(UNSAFE)
-       spin_lock_irq(instance->host_lock);
-#endif                         /* defined(REAL_DMA_POLL) */
        return foo;
 #endif                         /* def REAL_DMA */
 }
Index: linux/drivers/scsi/dtc.c
===================================================================
--- linux.orig/drivers/scsi/dtc.c       2015-11-18 19:33:35.000000000 +1100
+++ linux/drivers/scsi/dtc.c    2015-11-18 19:33:52.000000000 +1100
@@ -1,7 +1,5 @@
-
 #define PSEUDO_DMA
 #define DONT_USE_INTR
-#define UNSAFE                 /* Leave interrupts enabled during pseudo-dma 
I/O */
 #define DMA_WORKS_RIGHT
 
 
Index: linux/drivers/scsi/pas16.c
===================================================================
--- linux.orig/drivers/scsi/pas16.c     2015-11-18 19:33:27.000000000 +1100
+++ linux/drivers/scsi/pas16.c  2015-11-18 19:33:52.000000000 +1100
@@ -1,5 +1,4 @@
 #define PSEUDO_DMA
-#define UNSAFE  /* Not unsafe for PAS16 -- use it */
 
 /*
  * This driver adapted from Drew Eckhardt's Trantor T128 driver


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