Steinar Bang wrote:
> I am trying to get a Digital PC 5510, running SuSE 6.2 (kernel 2.2.10),
> connected to a Canon Bjc-4200 through the built-in parallell port
> /var/log/messages have the following messages about the parport, which
> is the only messages I have about the parport, and came into the log
> at the same point as I first tried to define the printer in YaST:
> Jun 18 13:12:11 doohan kernel: 0x378: CTR: wrote 0x0c, read 0xff
> Jun 18 13:12:11 doohan kernel: 0x378: DATA: wrote 0xaa, read 0xff
> Jun 18 13:12:11 doohan kernel: parport0: PC-style at 0x378 [SPP,PS2]
> Jun 18 13:12:11 doohan kernel: parport0: no IEEE-1284 device present.
> Jun 18 13:12:11 doohan kernel: lp0: using parport0 (polling).
>
Probably your parallel port is not at 0x378.
If you provide io=0x378 in /etc/conf.modules (or /etc/modules.conf or elsewhere)
the autodetection is disabled and parport trusts you blindly !
Non-existant ISA ports read back as 0xff (see CTR and DATA above).
Tim, should parport_pc contain better warnings (patch appended)?
Does anybody have some parallel port, that works despite these warnings?
Regards, Gunther
--- linux/drivers/misc/parport_pc.c-orig-2.2.15 Sun Jun 18 20:17:27 2000
+++ linux/drivers/misc/parport_pc.c Sun Jun 18 20:41:28 2000
@@ -353,6 +353,12 @@
/*
* Checks for port existence, all ports support SPP MODE
+ * Returns:
+ * 0 : No parallel port at this adress
+ * PARPORT_MODE_PCSPP : SPP port detected
+ * (if the user specified an ioport himself,
+ * this shall always be the case!)
+ *
*/
static int parport_SPP_supported(struct parport *pb)
{
@@ -387,7 +393,7 @@
if (user_specified)
/* That didn't work, but the user thinks there's a
* port here. */
- printk (KERN_DEBUG "0x%lx: CTR: wrote 0x%02x, read 0x%02x\n",
+ printk (KERN_DEBUG "parport 0x%lx (WARNING): CTR: wrote 0x%02x, read 0x%02x\n",
pb->base, w, r);
/* Try the data register. The data lines aren't tri-stated at
@@ -403,11 +409,14 @@
return PARPORT_MODE_PCSPP;
}
- if (user_specified)
+ if (user_specified) {
/* Didn't work with 0xaa, but the user is convinced
* this is the place. */
- printk (KERN_DEBUG "0x%lx: DATA: wrote 0x%02x, read 0x%02x\n",
+ printk (KERN_DEBUG "parport 0x%lx (WARNING): DATA: wrote 0x%02x, read 0x%02x\n",
pb->base, w, r);
+ printk (KERN_DEBUG "parport 0x%lx: You gave this address, but here is %s "
+ "no parallel port!\n", pb->base, r==0xff ? "surely" : "probably");
+ }
/* It's possible that we can't read the control register or
the data register. In that case just believe the user. */
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This archive was generated by hypermail 2b29 : Sun Jun 18 2000 - 15:06:44 EDT