staging: comedi: quatech_daqp_cs: use comedi_subdevice 'readback'

Use the new comedi_subdevice 'readback' member and the core provided
(*insn_read) for the readback of the analog output subdevice channels.

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>

diff --git a/drivers/staging/comedi/drivers/quatech_daqp_cs.c b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
index 489f4c8..6407df0 100644 (file)
--- a/drivers/staging/comedi/drivers/quatech_daqp_cs.c
+++ b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
@@ -649,6 +649,8 @@ static int daqp_ao_insn_write(struct comedi_device *dev,
        for (i = 0; i > insn->n; i++) {
                unsigned val = data[i];
 
+               s->readback[chan] = val;
+
                val &= 0x0fff;
                val ^= 0x0800;          /* Flip the sign */
                val |= (chan << 12);
@@ -739,6 +741,11 @@ static int daqp_auto_attach(struct comedi_device *dev,
        s->maxdata      = 0x0fff;
        s->range_table  = &range_bipolar5;
        s->insn_write   = daqp_ao_insn_write;
+       s->insn_read    = comedi_readback_insn_read;
+
+       ret = comedi_alloc_subdev_readback(s);
+       if (ret)
+               return ret;
 
        s = &dev->subdevices[2];
        s->type         = COMEDI_SUBD_DI;