diff options
| -rw-r--r-- | drivers/staging/comedi/drivers/c6xdigio.c | 35 |
1 files changed, 32 insertions, 3 deletions
diff --git a/drivers/staging/comedi/drivers/c6xdigio.c b/drivers/staging/comedi/drivers/c6xdigio.c index 20a5dfe..4114cf2 100644 --- a/drivers/staging/comedi/drivers/c6xdigio.c +++ b/drivers/staging/comedi/drivers/c6xdigio.c @@ -162,13 +162,41 @@ static int c6xdigio_pwm_insn_write(struct comedi_device *dev, unsigned int *data) { unsigned int chan = CR_CHAN(insn->chanspec); + unsigned int val = (s->state >> (16 * chan)) & 0xffff; int i; for (i = 0; i < insn->n; i++) { - c6xdigio_pwm_write(dev, chan, data[i]); - /* devpriv->ao_readback[chan] = data[i]; */ + val = data[i]; + c6xdigio_pwm_write(dev, chan, val); } - return i; + + /* + * There are only 2 PWM channels and they have a maxdata of 500. + * Instead of allocating private data to save the values in for + * readback this driver just packs the values for the two channels + * in the s->state. + */ + s->state &= (0xffff << (16 * chan)); + s->state |= (val << (16 * chan)); + + return insn->n; +} + +static int c6xdigio_pwm_insn_read(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_insn *insn, + unsigned int *data) +{ + unsigned int chan = CR_CHAN(insn->chanspec); + unsigned int val; + int i; + + val = (s->state >> (16 * chan)) & 0xffff; + + for (i = 0; i < insn->n; i++) + data[i] = val; + + return insn->n; } static int c6xdigio_encoder_insn_read(struct comedi_device *dev, @@ -243,6 +271,7 @@ static int c6xdigio_attach(struct comedi_device *dev, s->maxdata = 500; s->range_table = &range_unknown; s->insn_write = c6xdigio_pwm_insn_write; + s->insn_read = c6xdigio_pwm_insn_read; s = &dev->subdevices[1]; /* encoder (counter) subdevice */ |