From 6092e9428de76606d4fd337422322aee857a3e1a Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Wed, 5 Jun 2013 15:38:14 -0700 Subject: [PATCH] staging: comedi: pcmad: properly handle single/diff input configuration The comedi_config utility is used to attach to this board. One of the configuration options passed by the user sets the analog input reference for single-ended or differential inputs. Use the configuration option to correctly set the comedi_subdevice flags as well as the number of channels. Remove the 'differential' variable from the private data. Its not used by the driver. Signed-off-by: H Hartley Sweeten Cc: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/pcmad.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/drivers/staging/comedi/drivers/pcmad.c b/drivers/staging/comedi/drivers/pcmad.c index 94f50f6..86597fc 100644 --- a/drivers/staging/comedi/drivers/pcmad.c +++ b/drivers/staging/comedi/drivers/pcmad.c @@ -30,9 +30,9 @@ * Configuration options: * [0] - I/O port base * [1] - IRQ (unused) - * [2] - Analog input reference - * 0 = single ended - * 1 = differential + * [2] - Analog input reference (must match jumpers) + * 0 = single-ended (16 channels) + * 1 = differential (8 channels) * [3] - Analog input encoding (must match jumpers) * 0 = straight binary * 1 = two's complement @@ -64,7 +64,6 @@ static const struct pcmad_board_struct pcmad_boards[] = { }; struct pcmad_priv_struct { - int differential; int twos_comp; }; @@ -134,8 +133,15 @@ static int pcmad_attach(struct comedi_device *dev, struct comedi_devconfig *it) s = &dev->subdevices[0]; s->type = COMEDI_SUBD_AI; - s->subdev_flags = SDF_READABLE | AREF_GROUND; - s->n_chan = 16; + if (it->options[1]) { + /* 8 differential channels */ + s->subdev_flags = SDF_READABLE | AREF_DIFF; + s->n_chan = 8; + } else { + /* 16 single-ended channels */ + s->subdev_flags = SDF_READABLE | AREF_GROUND; + s->n_chan = 16; + } s->len_chanlist = 1; s->maxdata = board->ai_maxdata; s->range_table = &range_unknown; -- 2.7.4