A major:minor collision in 2.6.15

[Russell King]

On Tue, Feb 14, 2006 at 09:48:57AM +0200, Alon Keren wrote:
> On 2/14/06, Russell King <rmk+pcmcia at arm.linux.org.uk> wrote:
> > On Mon, Feb 13, 2006 at 09:30:55PM +0200, Alon Keren wrote:
> > > I have the following setup:
> > > Kernel: 2.6.15
> > > pcmciautils-012
> > > PCMCIA-card: Advantech's COMpad-32/85
> > >
> > > For some reason, my card seems to be in conflict with another card (an
> > > old V.34 modem) for the same major:minor numbers - 4:65.
> >
> > Please provide the contents of /proc/tty/driver/serial for each of these
> > cases.  Thanks.
> >
> 
> The contents of '/proc/tty/driver/serial' in the 2.6.15 machine:
> When NO cards are in:
> 
>         serinfo:1.0 driver revision:
>         0: uart:16550A port:000003F8 irq:4 tx:0 rx:0
>         1: uart:unknown port:00004338 irq:3
>         2: uart:16550A port:000003E8 irq:4 tx:0 rx:0
>         3: uart:unknown port:00004330 irq:3

Okay, so two ports were detected at boot time, and the driver is
configured to have a maximum of four ports.  You're trying to add
three additional ports, at least one has to fail.

> The file's contents in the 2.6.11 machine, when the COMpad is inserted first:
> 
> 	serinfo:1.0 driver revision:
> 	0: uart:16550A port:000003F8 irq:4 tx:0 rx:0
> 	1: uart:16550A port:000002F8 irq:5 tx:0 rx:0 CTS|DSR
> 	2: uart:16550A port:000003E8 irq:4 tx:0 rx:0
> 	3: uart:unknown port:000002E8 irq:3
> 	4: uart:unknown port:000001A0 irq:9
> 	5: uart:unknown port:000001A8 irq:9
> 	6: uart:unknown port:000001B0 irq:9
> 	7: uart:unknown port:000001B8 irq:9

whereas this one has a maximum of 48 ports configured.

Check the setting of CONFIG_SERIAL_8250_NR_UARTS and (if you have it)
CONFIG_SERIAL_8250_RUNTIME_UARTS.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 Serial core