The `insn_write` handler for the AO subdevice (`ao_winsn()` currently
ignores `insn->n` (the number of samples to write) and assumes a single
sample is to be written. But `insn->n` could be 0, meaning no samples
should be written, in which case `data[0]` is invalid.
Follow the usual Comedi guidelines and change `ao_winsn()` to write the
specified number of samples. This fixes the assumption that `data[0]`
is valid.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
{
const struct pcidas64_board *board = dev->board_ptr;
struct pcidas64_private *devpriv = dev->private;
{
const struct pcidas64_board *board = dev->board_ptr;
struct pcidas64_private *devpriv = dev->private;
- int chan = CR_CHAN(insn->chanspec);
- int range = CR_RANGE(insn->chanspec);
+ unsigned int chan = CR_CHAN(insn->chanspec);
+ unsigned int range = CR_RANGE(insn->chanspec);
+ unsigned int val = s->readback[chan];
+ unsigned int i;
/* do some initializing */
writew(0, devpriv->main_iobase + DAC_CONTROL0_REG);
/* do some initializing */
writew(0, devpriv->main_iobase + DAC_CONTROL0_REG);
writew(devpriv->dac_control1_bits,
devpriv->main_iobase + DAC_CONTROL1_REG);
writew(devpriv->dac_control1_bits,
devpriv->main_iobase + DAC_CONTROL1_REG);
- /* write to channel */
- if (board->layout == LAYOUT_4020) {
- writew(data[0] & 0xff,
- devpriv->main_iobase + dac_lsb_4020_reg(chan));
- writew((data[0] >> 8) & 0xf,
- devpriv->main_iobase + dac_msb_4020_reg(chan));
- } else {
- writew(data[0], devpriv->main_iobase + dac_convert_reg(chan));
+ for (i = 0; i < insn->n; i++) {
+ /* write to channel */
+ val = data[i];
+ if (board->layout == LAYOUT_4020) {
+ writew(val & 0xff,
+ devpriv->main_iobase + dac_lsb_4020_reg(chan));
+ writew((val >> 8) & 0xf,
+ devpriv->main_iobase + dac_msb_4020_reg(chan));
+ } else {
+ writew(val,
+ devpriv->main_iobase + dac_convert_reg(chan));
+ }
- /* remember output value */
- s->readback[chan] = data[0];
+ /* remember last output value */
+ s->readback[chan] = val;
}
static void set_dac_control0_reg(struct comedi_device *dev,
}
static void set_dac_control0_reg(struct comedi_device *dev,