serial port mystery

[Bill McCormick]

Bob Chiodini said the following on 4/4/2005 5:37 AM:
> On Sun, 2005-04-03 at 18:00 -0500, Bill McCormick wrote:
> 
>>Sometime ago I upgraded to FC3 from RedHat 9 to, among other reasons,
>>get my VScom PCI 2 port serial card working.
>>
>>(RedHat 9 required a kernel re-compile)
>>
>>Anyway FC3 made it work. The two ports have been working for sometime on
>>/dev/ttyS4 & 5. Now, inexplicably (after a reboot test) the 2 ports
>>insist on using /dev/ttyS14 & 15.
>>
>>I removed my rc.serial ...
>>
>><reference>
>>[root at billinux ~]# cat /tmp/rc.serial
>>setserial /dev/ttyS4 port 0xeca8 autoconfig
>>setserial /dev/ttyS5 port 0xec98 autoconfig
>></reference>
>>
>>... and still they come up as ttyS14 & 15.
>>
>>Somehow, the kernel must be doing this. But how? ACPI?  Where is the
>>config?
>>How might this have changed? yum?
>>Can I still use a rc.serial?
>>How can I get the ports permissions set to 666?
>>
>><reference from: dmesg>
>>ACPI: PCI interrupt 0000:00:04.0[A] -> GSI 25 (level, low) -> IRQ 177
>>ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
>>ttyS14 at I/O 0xeca8 (irq = 177) is a 16550A
>>ttyS15 at I/O 0xec98 (irq = 177) is a 16550A
>>ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
>></reference>
> 
> 
> Bill,
> 
> Once you figure out the devices names, the default permissions can be
> set in /etc/udev/permissions.d/50-local.permissions.  Add a line like:
> 
> ttyS*:root:uucp:0660
> 
> Change the 0660 as you need.
> 
> Bob...
> 
I did't need to add the line: it was already there. Since this is a home
  system, I care not if ALL ttyS* ports have a+rw.