From 1271dd24c63478b08fc574ec8b4fa50902b368f0 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten <hsweeten@visionengravers.com> Date: Mon, 5 Oct 2015 14:22:51 -0700 Subject: [PATCH] staging: comedi: quatech_daqp_cs: use comedi_offset_munge() in ao (*insn_write) Use the comedi_offset_munge() helper to do the offset binary to two's complement conversion when writing a new analog output value. 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> --- drivers/staging/comedi/drivers/quatech_daqp_cs.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/staging/comedi/drivers/quatech_daqp_cs.c b/drivers/staging/comedi/drivers/quatech_daqp_cs.c index cf144ce553c1f..4f87147213d1b 100644 --- a/drivers/staging/comedi/drivers/quatech_daqp_cs.c +++ b/drivers/staging/comedi/drivers/quatech_daqp_cs.c @@ -655,11 +655,9 @@ static int daqp_ao_insn_write(struct comedi_device *dev, s->readback[chan] = val; - val &= 0x0fff; - val ^= 0x0800; /* Flip the sign */ - val |= (chan << 12); - - outw(val, dev->iobase + DAQP_DA); + /* write the two's complement value to the channel */ + outw((chan << 12) | comedi_offset_munge(s, val), + dev->iobase + DAQP_DA); } return insn->n; -- 2.30.2