mac_scsi: fix mac_scsi on some powerbooks

Fix the mac_scsi interrupt edge trigger on non-RBV PowerBooks. This doesn't appear to help my PowerBook 520 but the NetBSD source reveals that the PowerBook 500 series is different than the others.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

1 files changed, 20 insertions, 14 deletions

diff --git a/arch/m68k/mac/via.c b/arch/m68k/mac/via.c
index 97996a48b048..7a2993bb092d 100644
--- a/arch/m68k/mac/via.c
+++ b/arch/m68k/mac/via.c
@@ -253,22 +253,28 @@ void __init via_init(void)
                 via2[vACR] &= ~0x03; /* disable port A & B latches */
         }
 
+        /* Everything below this point is VIA2 only... */
+
+        if (rbv_present)
+                return;
+
         /*
-         * Set vPCR for control line interrupts (but not on RBV)
+         * Set vPCR for control line interrupts.
+         *
+         * CA1 (SLOTS IRQ), CB1 (ASC IRQ): negative edge trigger.
+         *
+         * Macs with ESP SCSI have a negative edge triggered SCSI interrupt.
+         * Testing reveals that PowerBooks do too. However, the SE/30
+         * schematic diagram shows an active high NCR5380 IRQ line.
          */
-        if (!rbv_present) {
-                /* For all VIA types, CA1 (SLOTS IRQ) and CB1 (ASC IRQ)
-                 * are made negative edge triggered here.
-                 */
-                if (macintosh_config->scsi_type == MAC_SCSI_OLD) {
-                        /* CB2 (IRQ) indep. input, positive edge */
-                        /* CA2 (DRQ) indep. input, positive edge */
-                        via2[vPCR] = 0x66;
-                } else {
-                        /* CB2 (IRQ) indep. input, negative edge */
-                        /* CA2 (DRQ) indep. input, negative edge */
-                        via2[vPCR] = 0x22;
-                }
+
+        pr_debug("VIA2 vPCR is 0x%02X\n", via2[vPCR]);
+        if (macintosh_config->via_type == MAC_VIA_II) {
+                /* CA2 (SCSI DRQ), CB2 (SCSI IRQ): indep. input, pos. edge */
+                via2[vPCR] = 0x66;
+        } else {
+                /* CA2 (SCSI DRQ), CB2 (SCSI IRQ): indep. input, neg. edge */
+                via2[vPCR] = 0x22;
         }
 }