1bf7ebc42f
Commit r9750 "wct4xxp: Reduce the memory footprint of the hardware echocanceler.", as part of reducing the non-pageable memory required to support the VPMOCT064 and VPMOCT128, disabled caching of some hardware echocan registers. This resulted in more physical reads to the echo canceler. These new read transactions exposed an existing issue where sometimes reads could be turned into writes which put a channel into an unintended state preventing Asterisk from detecting any DTMF. This issue is resolved by ensuring that the write signal to the Octasic part is explicitly cleared between when the address is presented on the bus and when the read and chip select signals are asserted. The cost is an increase in the average time to enable / disable echo cancellation by about 5 us on one Intel Xeon X3220 test machine (~250ns increase per read from the Octasic part and 20 reads to enable / disable a channel). This commit resolves a behavioral regression first introduced in 2.5.0 and 2.4.1 which could take many calls before revealing itself. This change only affects cards with a VPMOCT128 or VPMOCT064 installed. Signed-off-by: Shaun Ruffell <sruffell@digium.com> Acked-by: Doug Bailey <dbailey@digium.com> Origin: http://svnview.digium.com/svn/dahdi?view=rev&rev=10220 git-svn-id: http://svn.asterisk.org/svn/dahdi/linux/branches/2.5@10221 a0bf4364-ded3-4de4-8d8a-66a801d63aff |
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| .. | ||
| base.c | ||
| Kbuild | ||
| Makefile | ||
| vpm450m.c | ||
| vpm450m.h | ||
| wct4xxp-diag.c | ||
| wct4xxp.h | ||