I ran into the strange behaviour that linux did not recognize
my printer port. A bit of kernel debugging showed me that it
was the outb_p/inb_p test with LP_DUMMY that failed.
I fixed it by faking that the test succeed (see code diff below).
Computer: Compaq Presario 5670
Processor: Intel Pentium II, 450 MHz
RAM: 128 MB
Distribution: SuSE Linux 5.3
Kernel: linux-2.0.35.SuSE
I thought that you would like to know about the problem
on the Compaq Presario 5670. I would also appriciate it
if you have a better idea for the workaround.
Thanx,
/Tom
** linux/drivers/char/lp.c Sun Jan 17 19:43:44 1999
--- linux-2.0.35.SuSE/drivers/char/lp.c Wed Jul 29 17:32:40 1998
***************
*** 557,583 ****
{
int base, size;
unsigned int testvalue;
! printk(KERN_INFO "probing for lp%d\n", offset);
base = LP_B(offset);
- printk(KERN_INFO "probing for lp%d at base=0x%x, irq=%d\n",
- offset, base, LP_IRQ(offset) );
if (base == 0)
return -1; /* de-configured by command line */
if (LP_IRQ(offset) > 15)
return -1; /* bogus interrupt value */
size = (base == 0x3bc)? 3 : 8;
! if (check_region(base, size) < 0) {
! printk(KERN_INFO "check_region(0x%x, %d) failed\n", base, size);
return -1;
- }
/* write to port & read back to check */
outb_p(LP_DUMMY, base);
! udelay(LP_DELAY*10);
testvalue = inb_p(base);
- if (testvalue != LP_DUMMY) {
- printk(KERN_WARNING "lp%d at 0x%04x, not OK faking\n", offset, base);
- testvalue = LP_DUMMY;
- }
if (testvalue == LP_DUMMY) {
LP_F(offset) |= LP_EXIST;
lp_reset(offset);
---------------------------------------------------------------
Tom Bjorkholm Serenadvagen 36, 3tr email: tom.bjorkholm@swipnet.se
Tel/Fax: 131 40 Nacka tom.bjorkholm@ebc.ericsson.se
08-7166894 Sweden
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