icE1usb: update manual to reflect firmware 0.2 (GPS-DO, 2 ports)
Change-Id: I9dac5b9479af37270dc13e334a278f91f260c7ce
diff --git a/doc/manuals/chapters/host-software.adoc b/doc/manuals/chapters/host-software.adoc
index 356c897..4c8578e 100644
--- a/doc/manuals/chapters/host-software.adoc
+++ b/doc/manuals/chapters/host-software.adoc
@@ -3,13 +3,19 @@
Host Software is software running on the USB host computer to which the
icE1usb is attached.
-At the time of this writing, the only software implementing icE1usb
-support is `osmo-e1d`.
+At the time of this writing, there are two options for icE1usb driver interfaces:
+`osmo-e1d` and `DAHDI`.
=== `osmo-e1d`
-`osmo-e1d` utilizes `libusb` to talk to the icE1usb hardware and offers
-a unix domain socket based interface to application software.
+`osmo-e1d` is a pure user-space driver, not requiring any specific Linux kernel,
+kernel patches or out-of-tree kernel modules. It utilizes `libusb` to
+talk to the icE1usb hardware and offers a unix domain socket based
+interface to application software.
+
+In theory, `osmo-e1d` should work on any operating system with libusb
+support for isochronous transfers. However, official support is limited
+to GNU/Linux at this point.
Software such as `osmo-bsc` and `osmo-mgw` can interface `osmo-e1d` via
the `libosmo-abis` support for `osmo-e1d`.
@@ -23,6 +29,11 @@
popular driver for a variety of POTS/PSTN and also TDM interface boards
by originally Zaptel, later Digium and now most recently Sangoma.
+DAHDI is available only for Linux, and is provided as source code for a
+set of out-of-tree kernel modules. You must compile those modules for
+each specific Linux kernel version you are using. Keep this in mind
+when performing kernel upgrades and the like.
+
DAHDI is supported by a wide range of open source PBX / softswitch software,
including Asterisk, FreeSWITCH and yate.