staging: comedi: dt9812: cleanup analog in subdevice (*insn_read)

For aesthetic reasons, rename the function to help with grepping and
rename some of the local vars.

dt9812_analog_in() can fail. Make sure to check for any failure and
return the errno.

The comedi core expects the (*insn_read) functions to return either
an errno or the number of samples read. Change the final return to
insn->n to make this clearer.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
H Hartley Sweeten 2013-05-14 14:33:09 -07:00 committed by Greg Kroah-Hartman
parent 36c973d089
commit 83a69f5adb

View file

@ -631,20 +631,24 @@ static int dt9812_do_insn_bits(struct comedi_device *dev,
return insn->n; return insn->n;
} }
static int dt9812_ai_rinsn(struct comedi_device *dev, static int dt9812_ai_insn_read(struct comedi_device *dev,
struct comedi_subdevice *s, struct comedi_insn *insn, struct comedi_subdevice *s,
unsigned int *data) struct comedi_insn *insn,
unsigned int *data)
{ {
unsigned int channel = CR_CHAN(insn->chanspec); unsigned int chan = CR_CHAN(insn->chanspec);
int n; u16 val = 0;
int ret;
int i;
for (n = 0; n < insn->n; n++) { for (i = 0; i < insn->n; i++) {
u16 value = 0; ret = dt9812_analog_in(dev, chan, &val, DT9812_GAIN_1);
if (ret)
dt9812_analog_in(dev, channel, &value, DT9812_GAIN_1); return ret;
data[n] = value; data[i] = val;
} }
return n;
return insn->n;
} }
static int dt9812_ao_rinsn(struct comedi_device *dev, static int dt9812_ao_rinsn(struct comedi_device *dev,
@ -845,7 +849,7 @@ static int dt9812_auto_attach(struct comedi_device *dev,
s->n_chan = 8; s->n_chan = 8;
s->maxdata = 0x0fff; s->maxdata = 0x0fff;
s->range_table = is_unipolar ? &range_unipolar2_5 : &range_bipolar10; s->range_table = is_unipolar ? &range_unipolar2_5 : &range_bipolar10;
s->insn_read = dt9812_ai_rinsn; s->insn_read = dt9812_ai_insn_read;
/* Analog Output subdevice */ /* Analog Output subdevice */
s = &dev->subdevices[3]; s = &dev->subdevices[3];