From 4d443a085de2b6bcae5e0a773c63b8731ff27101 Mon Sep 17 00:00:00 2001 From: Kumar Sanghvi Date: Mon, 27 Sep 2010 19:35:06 +0000 Subject: Documentation: Update Phonet doc for Pipe Controller implementation Updates the Phonet document with description related to Pipe controller implementation Signed-off-by: Kumar Sanghvi Acked-by: Linus Walleij Signed-off-by: David S. Miller --- Documentation/networking/phonet.txt | 53 +++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) (limited to 'Documentation/networking') diff --git a/Documentation/networking/phonet.txt b/Documentation/networking/phonet.txt index cf76608a2d35..cccf5ff07ec2 100644 --- a/Documentation/networking/phonet.txt +++ b/Documentation/networking/phonet.txt @@ -182,6 +182,59 @@ The pipe protocol provides two socket options at the SOL_PNPIPE level: or zero if encapsulation is off. +Phonet Pipe-controller Implementation +------------------------------------- + +Phonet Pipe-controller is enabled by selecting the CONFIG_PHONET_PIPECTRLR Kconfig +option. It is useful when communicating with those Nokia Modems which do not +implement Pipe controller in them e.g. Nokia Slim Modem used in ST-Ericsson +U8500 platform. + +The implementation is based on the Data Connection Establishment Sequence +depicted in 'Nokia Wireless Modem API - Wireless_modem_user_guide.pdf' +document. + +It allows a phonet sequenced socket (host-pep) to initiate a Pipe connection +between itself and a remote pipe-end point (e.g. modem). + +The implementation adds socket options at SOL_PNPIPE level: + + PNPIPE_CREATE + It accepts an integer argument where-in + lower order 16 bits: pn_dev and pn_port pair for remote pep. + higher order 16 bits: 8 bit pipe-handle + + It sends a PNS_PEP_CONNECT_REQ on sequenced socket itself. On getting + PNS_PEP_CONNECT_RESP, it sends PNS_PEP_CONNECT_REQ to remote pep. On + getting response from remote pep, it selects the best possible Flow + control mechanism supported by remote-pep (modem) and then it sends + PNS_PEP_CREATED_IND to the sequenced socket and to the remote pep. + + It then updates the pipe state associated with the sequenced socket to + be PIPE_DISABLED. + + PNPIPE_ENABLE + It follows the same sequence as above for enabling a pipe by sending + PNS_PEP_ENABLE_REQ initially and then sending PNS_PEP_ENABLED_IND after + getting responses from sequenced socket and remote-pep. + It will also update the pipe state associated with the sequenced socket + to PIPE_ENABLED. + + PNPIPE_DESTROY + This will send out PNS_PEP_DISCONNECT_REQ on the sequenced socket and + the remote pep. + It will also update the pipe state associated with the sequenced socket + to PIPE_IDLE + + PNPIPE_INQ + This getsocktopt allows the user-space running on the sequenced socket + to examine the pipe state associated with that socket ie. whether the + pipe is created (PIPE_DISABLED) or enabled (PIPE_ENABLED) or disabled + (PIPE_DISABLED) or no pipe exists (PIPE_IDLE). + +After a pipe has been created and enabled successfully, the Pipe data can be +exchanged between the host-pep and remote-pep (modem). + Authors ------- -- cgit v1.2.3