[asterisk-bugs] [DAHDI-linux 0015311]: [patch] Call to a FXS DAHDI channel with Panasonic KX-TG4000 connected drops in 8 seconds randomly

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15311 
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Reported By:                vmikhelson
Assigned To:                
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Project:                    DAHDI-linux
Issue ID:                   15311
Category:                   dahdi (the module)
Reproducibility:            random
Severity:                   major
Priority:                   normal
Status:                     new
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Date Submitted:             2009-06-11 00:49 CDT
Last Modified:              2009-06-17 07:02 CDT
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Summary:                    [patch] Call to a FXS DAHDI channel with Panasonic
KX-TG4000 connected drops in 8 seconds randomly
Description: 
More often than not a call placed to a DAHDI channel with Panasonic
KX-TG4000 connected would drop on its own in exactly 8 seconds after being
answered. Before being disconnected two (2) clicks are being heard in
succession. The second click kills the connection.
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 (0106545) alecdavis (reporter) - 2009-06-17 07:02
 https://issues.asterisk.org/view.php?id=15311#c106545 
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Uploaded dahdi_wctdm_click.diff2.txt
This forces the idletxhookstate to ACTIVE or REVERSE ACTIVE as soon as off
hook is detect on an FXS port. 

The initial patch dahdi_wctdm_click.diff.txt leaves the FXS module in 'On
Hook Tansmission' or 'Active' mode during the call. Depends on when OffHook
happened, there maybe merit in this, as CallWaiting ID can be sent over the
line, without any clicks, and perhaps not dropping the line. 

The click isn't the change in line polarity as I initially thought.

The click that is heard at 6 seconds, is the OHT-TIMER (On Hook Transfer)
timing out and changing from 'Forward/Reverse On-Hook Transmission' to
'Forward/Reverse Active'.

Repeatablity:
This click can be easily heard 6 seconds after the pickup of the called
extension only if the pickup was while it's ringing, not during a silent
period. That is where the randomness comes in.

I had to setup loadzone=US, as the ringcadence is long, I had trouble
initally here in NZ as we have a ring-ring-pause cadence.

This patch, doesn't have any printk's, so no debug can be seen. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-06-17 07:02 alecdavis      Note Added: 0106545                          
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