# Modem not responding after few hours

## zkosty

I believe that this issue is not gentoo-specific but I figured I should ask "at home" before taking my problem out....

I have a ACTIONTEC 56k V.92 PCI modem, hardware controlled, all good for Linux, all working fine. I use my Gentoo box as a home desktop computer and I rarely have it on for more than a few hours.

However, sometimes I leave it on all day. Then, after some time, the modem "dies" - it does not respond even to "AT" command (using KERMIT) and I can't connect to internet. The only thing I can do about it is to reboot the machine - then everything works fine again.

I would like to be able to fix this problem without rebooting - anybody knows a way? Is there a way to specifically reboot just the modem?

THANK YOU

ZKOSTY

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## zkosty

It is a PCI modem - can IRQ sharing be the problem?

How do I find out or/and what can I do about it?

zkosty

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## zkosty

And here is some more info about my hardware (this is done when the modem is working and connected to internet)

```
# setserial -g /dev/tts/*

/dev/tts/0, UART: 16550A, Port: 0x03f8, IRQ: 4

/dev/tts/1, UART: 16550A, Port: 0x02f8, IRQ: 3

/dev/tts/2, UART: unknown, Port: 0x03e8, IRQ: 4

/dev/tts/3, UART: unknown, Port: 0x02e8, IRQ: 3

/dev/tts/4, UART: 16550A, Port: 0x9000, IRQ: 5   # <---------------- HERE

................
```

```
# cat /proc/interrupts       

           CPU0       

  0:    4475334          XT-PIC  timer

  1:       8175          XT-PIC  i8042

  2:          0          XT-PIC  cascade

  5:      42082          XT-PIC  ohci_hcd, serial   # <------ HERE

  9:          0          XT-PIC  acpi

 10:          0          XT-PIC  ohci_hcd

 11:        733          XT-PIC  ehci_hcd, NVidia nForce2

 12:     226221          XT-PIC  i8042

 14:      14795          XT-PIC  ide0

 15:        175          XT-PIC  ide1

NMI:          0 

ERR:          0
```

```
# cat /proc/ioports

..........

5000-5007 : nForce2 SMBus

5100-5107 : nForce2 SMBus

9000-9fff : PCI Bus #01       # <------- HERE

  9000-90ff : 0000:01:09.0

    9000-9007 : serial

  9400-94ff : 0000:01:09.0

  9800-9807 : 0000:01:09.0

a000-afff : PCI Bus #02

................
```

```
# lspci -vv

........ (too long to display all output)

0000:01:09.0 Communication controller: Lucent Microelectronics Venus Modem (V90, 56KFlex)

        Subsystem: Actiontec Electronics Inc: Unknown device 0500

        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-

        Status: Cap+ 66Mhz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-

        Latency: 0 (63000ns min, 3500ns max)

        Interrupt: pin A routed to IRQ 5

        Region 0: Memory at ec000000 (32-bit, non-prefetchable)

        Region 1: I/O ports at 9000 [size=256]

        Region 2: I/O ports at 9400 [size=256]

        Region 3: I/O ports at 9800 [size=8]

        Capabilities: [f8] Power Management version 2

                Flags: PMEClk- DSI+ D1- D2+ AuxCurrent=0mA PME(D0-,D1-,D2+,D3hot+,D3cold+)

                Status: D0 PME-Enable- DSel=0 DScale=0 PME-

.........
```

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## zkosty

anybody?

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## fls

 *Quote:*   

> # cat /proc/interrupts
> 
> <snip>
> 
> 5:      42082          XT-PIC  ohci_hcd, serial   # <------ HERE
> ...

 

Can you see any relation between your modem failure and the usage of USB hardware?

This is only a blind guess (no other ideas here  :Sad:  ), but since your modem shares interrupt with your USB 2.0 controller it might be the problem.

Hope you find something  :Smile: 

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## fls

Also, have you tried to place your modem in a different PCI slot? This solved some weird sound problems for me once.

If you have a mainboard with a good manual you´ll find a table in it which PCI slot shares IRQ with whom, so you can chose a slot who doesn´t share at all or with a hardware wich is disabled in the BIOS.

For my Asus P4C800-E this would be slot 5 for example.

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## zkosty

It has been almost a year since the last post, several versions of kernel passed, and I am still stuck withthe same problem.

I do not see any relation to using the USB.

I did try other PCI slots on the motherboard and that did not help either.

Can it be something else? Is there a way to reset the modem without resetting the computer? (I tried to study the AT commands but didn't find anything useful.

Thanks  :Exclamation: 

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## m_sqrd

What is the output of

dmesg |egrep -i 'serial|tty'

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## zkosty

# dmesg |egrep -i 'serial|tty'

Serial: 8250/16550 driver $Revision: 1.90 $ 8 ports, IRQ sharing disabled

ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A

ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A

ttyS4 at I/O 0x9000 (irq = 5) is a 16550A

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## m_sqrd

I'd try setting these kernel options on and see if that helps

CONFIG_SERIAL_8250_EXTENDED

SERIAL_8250_SHARE_IRQ

SERIAL_8250_MULTIPORT

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## zkosty

OK I will try that.

It used to happen erratically, so to make sure, it will take me several days or weeks of observation of the results.

Thanks!

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## zkosty

OK I did that.

The problem keeps happening. I am out of ideas.

Any help?

 :cry:

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