From 1a021d6387337c828c6e15c7fc65f3e013163f89 Mon Sep 17 00:00:00 2001
From: H Hartley Sweeten <hsweeten@visionengravers.com>
Date: Tue, 9 Sep 2014 16:15:47 -0700
Subject: [PATCH] staging: comedi: das16m1: prevent "empty acquisition" async
 command

This driver currently allows a cmd->stop_src == TRIG_COUNT with a cmd->stop_arg
of 0. The (*do_cmd) then sets up and starts the command without handling the "empty
acquisition". This results in the interrupt function trying to transfer 0 data
samples.

Validate that the cmd->stop_arg is >= 1 in the (*do_cmdtest) to prevent the
"empty acquisition".

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
Reading git-format-patch failed