A major:minor collision in 2.6.15

[Alon Keren]

On 2/14/06, Russell King <rmk+pcmcia at arm.linux.org.uk> wrote:
> 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.
>

No 'CONFIG_SERIAL_8250_RUNTIME_UARTS'.
'CONFIG_SERIAL_8250_NR_UARTS' is set to "4" on both the 2.6.11 and the
2.6.15 machines.

If it's of any help:

`grep CONFIG_SERIAL_8250 .config` for the 2.6.15:

	CONFIG_SERIAL_8250=m
	CONFIG_SERIAL_8250_CS=m
	# CONFIG_SERIAL_8250_ACPI is not set
	CONFIG_SERIAL_8250_NR_UARTS=4
	CONFIG_SERIAL_8250_EXTENDED=y
	CONFIG_SERIAL_8250_MANY_PORTS=y
	CONFIG_SERIAL_8250_SHARE_IRQ=y
	# CONFIG_SERIAL_8250_DETECT_IRQ is not set
	# CONFIG_SERIAL_8250_RSA is not set
	# CONFIG_SERIAL_8250_FOURPORT is not set
	# CONFIG_SERIAL_8250_ACCENT is not set
	# CONFIG_SERIAL_8250_BOCA is not set
	# CONFIG_SERIAL_8250_HUB6 is not set


`grep CONFIG_SERIAL_8250 .config` for the 2.6.11:

	CONFIG_SERIAL_8250=m
	CONFIG_SERIAL_8250_CS=m
	# CONFIG_SERIAL_8250_ACPI is not set
	CONFIG_SERIAL_8250_NR_UARTS=4
	CONFIG_SERIAL_8250_EXTENDED=y
	CONFIG_SERIAL_8250_MANY_PORTS=y
	CONFIG_SERIAL_8250_SHARE_IRQ=y
	# CONFIG_SERIAL_8250_DETECT_IRQ is not set
	CONFIG_SERIAL_8250_MULTIPORT=y
	# CONFIG_SERIAL_8250_RSA is not set


- Alon