sam: note the two comms interface types for lpr

Also mask to bit 0 on the busy check

diff --git a/Kernel/platform-sam/devlpr.c b/Kernel/platform-sam/devlpr.c
index a6cc047..0eb4cdb 100644 (file)
--- a/Kernel/platform-sam/devlpr.c
+++ b/Kernel/platform-sam/devlpr.c
@@ -3,6 +3,14 @@
 #include <kdata.h>
 #include <devlpr.h>
 
+/* FIXME: There are two comms interfaces
+
+   1. The SPI printer port on 232/233 mode on 234 (supported here)
+   2. The MGT comms interface. Printer port on 232/233 or 234/235 but no
+      direction control, and 236-239 allow up to four SCC2691 UARTs
+
+   We support ether interface in the default jumpering */
+
 __sfr __at 232 lpdata;
 __sfr __at 233 lpstrobe;
 __sfr __at 233 lpbusy;
@@ -26,7 +34,7 @@ int lpr_close(uint8_t minor)
        return 0;
 }
 
-/* FIXME: review strobe delay requirement */
+/* The call is more than enough to ensure we make the parallel timing */
 static void nap(void)
 {
 }
@@ -54,7 +62,7 @@ int lpr_write(uint8_t minor, uint8_t rawflag, uint8_t flag)
        flag;
 
        while (udata.u_done < udata.u_count) {
-               while (lpbusy) {
+               while (lpbusy & 1) {
                        if (iopoll())
                                return udata.u_done;
                }
@@ -64,5 +72,5 @@ int lpr_write(uint8_t minor, uint8_t rawflag, uint8_t flag)
                lpstrobe = 0;
                udata.u_done++;
        }
-       return (-1);
+       return udata.u_done;
 }