Module Name: src
Committed By: ws
Date: Tue Feb 20 15:50:02 UTC 2018
Modified Files:
src/share/man/man4: ugen.4
Log Message:
Add description of how to attach ugen to only some of the
interfaces found in a device.
To generate a diff of this commit:
cvs rdiff -u -r1.32 -r1.33 src/share/man/man4/ugen.4
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/share/man/man4/ugen.4
diff -u src/share/man/man4/ugen.4:1.32 src/share/man/man4/ugen.4:1.33
--- src/share/man/man4/ugen.4:1.32 Mon Jul 3 21:30:58 2017
+++ src/share/man/man4/ugen.4 Tue Feb 20 15:50:02 2018
@@ -1,4 +1,4 @@
-.\" $NetBSD: ugen.4,v 1.32 2017/07/03 21:30:58 wiz Exp $
+.\" $NetBSD: ugen.4,v 1.33 2018/02/20 15:50:02 ws Exp $
.\"
.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
.\" All rights reserved.
@@ -35,6 +35,7 @@
.Nd USB generic device support
.Sh SYNOPSIS
.Cd "ugen* at uhub? flags N"
+.Cd "ugen* at uhub? vendor V product P configuration C interface I flags 1
.Sh DESCRIPTION
The
.Nm
@@ -60,6 +61,40 @@ locators this can be used to force the
driver to be used for a certain
device.
.Pp
+The second form of attachment can be used to
+.Dq steal
+only one interface from some device for use by the
+.Nm
+driver.
+Be sure to include
+.Dq flags 1
+on the attachment.
+.Em NOTE :
+You have to be extremely careful,
+when using this,
+as the attached
+.Nm
+driver has access to all of the device
+and can easily interfere with the driver used for
+the other interface(s).
+.Pp
+As an example of this second form of attachment there are
+various debugging boards available based on some FTDI chip,
+where one interface is used for JTAG debugging
+and the other is used as a serial interface.
+In this case you want to attach the
+.Nm
+driver to interface 0
+while using
+.Xr uftdi 4
+together with
+.Xr ucom 4
+at interface 1 of this particular board
+identified by
+.Cd vendor
+and
+.Cd product .
+.Pp
There can be up to 127 USB devices connected to a USB bus.
Each USB device can have up to 16 endpoints.
Each of these endpoints will communicate in one of four different
