From d62e8055a596b3d3f11c1643ba18a9cbf093a0b9 Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Wed, 11 Sep 2019 17:39:41 +0100 Subject: [PATCH] devices.txt: improve entry for comedi (char major 98) Describe how the comedi minor device numbers are split across comedi devices and comedi subdevices. Replace the current, long dead URL with an official URL for the Comedi project. Signed-off-by: Ian Abbott Signed-off-by: Jonathan Corbet --- Documentation/admin-guide/devices.txt | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/devices.txt b/Documentation/admin-guide/devices.txt index e56e00655153..1c5d2281efc9 100644 --- a/Documentation/admin-guide/devices.txt +++ b/Documentation/admin-guide/devices.txt @@ -1647,8 +1647,17 @@ 0 = /dev/comedi0 First comedi device 1 = /dev/comedi1 Second comedi device ... + 47 = /dev/comedi47 48th comedi device - See http://stm.lbl.gov/comedi. + Minors 48 to 255 are reserved for comedi subdevices with + pathnames of the form "/dev/comediX_subdY", where "X" is the + minor number of the associated comedi device and "Y" is the + subdevice number. These subdevice minors are assigned + dynamically, so there is no fixed mapping from subdevice + pathnames to minor numbers. + + See http://www.comedi.org/ for information about the Comedi + project. 98 block User-mode virtual block device 0 = /dev/ubda First user-mode block device