[2812] in linux-scsi channel archive
fix for seagate driver
daemon@ATHENA.MIT.EDU (Egbert Eich)
Fri Nov 14 05:42:14 1997
Date: Fri, 14 Nov 1997 11:38:23 +0100
From: Egbert Eich <eich@crunch.ikp.physik.tu-darmstadt.de>
To: linux-scsi@vger.rutgers.edu
Hi,
could someone on this list please tell me who currently maintains
the seagate st0x-driver?
I have a patch for it which has been in my drawer for quite a while.
I thought Drew Eckhardt was maintainer of this driver. I have mailed
it to him twice however never received an answer.
I know it's very outdated hardware and no one wants to bother with it.
But until I decide to retire my 33MHz 486 I'm going to use it. It still
works well (at least I don't get problems provided I'm using this fix).
This patch fixes the long standing problem with the order of CONTROL/DATA.
The solution which is suggested now is clumsy and doesn't work for
me as one of my two disks wants it the other way around from the
second.
I changed it to be more SCSI standard compliant. Now my two
disks - along with a CDROM and a MOD drive - work flawlessly.
Besides I've tested this fix on a different system, a DELL notebook
with a port replicator which uses a FD TMC-8xx. There it works without
problems, too.
Cheers,
Egbert.
The fix is against 2.1.55.
--- seagate.c.org Wed Sep 24 16:27:05 1997
+++ seagate.c Wed Sep 24 16:33:41 1997
@@ -72,6 +72,13 @@
* x is some number, It will let you specify a default
* transfer rate if handshaking isn't working correctly.
*
+ * -DOLDCNTDATASCEME There is a new sceme to set the CONTROL
+ * and DATA reigsters which complies more closely
+ * with the SCSI2 standard. This hopefully eliminates
+ * the need to swap the order these registers are
+ * 'messed' with. It makes the following two options
+ * obsolete. To reenable the old sceme define this.
+ *
* The following to options are patches from the SCSI.HOWTO
*
* -DSWAPSTAT This will swap the definitions for STAT_MSG and STAT_CD.
@@ -794,6 +801,10 @@
unsigned char message = 0;
register unsigned char status_read;
+#ifndef OLDCNTDATASCEME
+ volatile unsigned char tmp_data;
+ volatile unsigned char tmp_control;
+#endif
unsigned transfersize = 0, underflow = 0;
incommand = 0;
@@ -1029,6 +1040,7 @@
* try this with a SCSI protocol or logic analyzer to see what is
* going on.
*/
+#ifdef OLDCNTDATASCEME
#ifdef SWAPCNTDATA
cli();
WRITE_CONTROL (BASE_CMD | CMD_DRVR_ENABLE | CMD_SEL |
@@ -1044,6 +1056,16 @@
(reselect ? CMD_ATTN : 0));
sti ();
#endif
+#else
+ tmp_data = (unsigned char) ((1 << target) | (controller_type == SEAGATE
+? 0x80 : 0x40));
+ tmp_control = BASE_CMD | CMD_DRVR_ENABLE | CMD_SEL |
+ (reselect ? CMD_ATTN : 0) | CMD_BSY;
+ WRITE_CONTROL(tmp_data);
+ WRITE_DATA(tmp_control);
+ tmp_control ^= CMD_BSY;
+ WRITE_CONTROL(tmp_control);
+#endif /* OLDCNTDATASCEME */
while (!((status_read = STATUS) & STAT_BSY) && (jiffies < clock)
&& !st0x_aborted)
#if 0 && (DEBUG & PHASE_SELECTION)
