Serial port numbering (ttyS..) wrong for 2.5.61+

From: Ruud Linders (
Date: Sun Jun 01 2003 - 06:14:45 EST

Since I tried the 2.5 kernel versions somewhere in the 2.5.6x range, I
see rather odd port naming for the extra 4 serial ports on a PCI-card.

The first two are numered as ttyS14, ttyS15 while the last two are
ttyS2 and ttyS3 !
I tried to find where these numbers are coming from but couldn't really
find an obvious place in the various drivers/char/* or drivers/serial/*

Note that the ttyS14 port actually works so this seems only a bug in
the numbering.

Ruud Linders

Kernel version 2.5.70
Serial: 8250/16550 driver $Revision: 1.90 $ IRQ sharing enabled
ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
ttyS14 at I/O 0xbc00 (irq = 21) is a 16550A <<<<<< 14 ????
ttyS15 at I/O 0xbc08 (irq = 21) is a 16550A <<<<<<
ttyS2 at I/O 0xbc10 (irq = 21) is a 16550A
ttyS3 at I/O 0xbc18 (irq = 21) is a 16550A

4-port PCI serial controller:
# lspci -d 10b5:1077 -v
02:0b.0 Serial controller: PLX Technology, Inc. VScom 400 4 port serial
(rev 02) (prog-if 00 [8250])
         Subsystem: PLX Technology, Inc. VScom 400 4 port serial adaptor
         Flags: medium devsel, IRQ 21
         Memory at de004000 (32-bit, non-prefetchable) [size=128]
         I/O ports at b800 [size=128]
         I/O ports at bc00 [size=32]
         I/O ports at c000 [size=8]
         Expansion ROM at <unassigned> [disabled] [size=2K]

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