From: H Hartley Sweeten <hsweeten@visionengravers.com>
Date: Mon, 25 Aug 2014 23:04:39 +0000 (-0700)
Subject: staging: comedi: rti800: use comedi_subdevice 'readback'
X-Git-Tag: v3.18-rc1~130^2~1013
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=35e769c4717cf08f71cd5c7a9e34aece3ff8852e;p=karo-tx-linux.git

staging: comedi: rti800: 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/rti800.c b/drivers/staging/comedi/drivers/rti800.c
index 01ec65a5b5d1..4df979e519f0 100644
--- a/drivers/staging/comedi/drivers/rti800.c
+++ b/drivers/staging/comedi/drivers/rti800.c
@@ -137,7 +137,6 @@ struct rti800_private {
 	bool adc_2comp;
 	bool dac_2comp[2];
 	const struct comedi_lrange *ao_range_type_list[2];
-	unsigned int ao_readback[2];
 	unsigned char muxgain_bits;
 };
 
@@ -207,21 +206,6 @@ static int rti800_ai_insn_read(struct comedi_device *dev,
 	return insn->n;
 }
 
-static int rti800_ao_insn_read(struct comedi_device *dev,
-			       struct comedi_subdevice *s,
-			       struct comedi_insn *insn,
-			       unsigned int *data)
-{
-	struct rti800_private *devpriv = dev->private;
-	unsigned int chan = CR_CHAN(insn->chanspec);
-	int i;
-
-	for (i = 0; i < insn->n; i++)
-		data[i] = devpriv->ao_readback[chan];
-
-	return insn->n;
-}
-
 static int rti800_ao_insn_write(struct comedi_device *dev,
 				struct comedi_subdevice *s,
 				struct comedi_insn *insn,
@@ -236,7 +220,7 @@ static int rti800_ao_insn_write(struct comedi_device *dev,
 	for (i = 0; i < insn->n; i++) {
 		unsigned int val = data[i];
 
-		devpriv->ao_readback[chan] = val;
+		s->readback[chan] = val;
 
 		if (devpriv->dac_2comp[chan])
 			val ^= 0x800;
@@ -318,8 +302,6 @@ static int rti800_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 		s->type		= COMEDI_SUBD_AO;
 		s->subdev_flags	= SDF_WRITABLE;
 		s->n_chan	= 2;
-		s->insn_read	= rti800_ao_insn_read;
-		s->insn_write	= rti800_ao_insn_write;
 		s->maxdata	= 0x0fff;
 		s->range_table_list = devpriv->ao_range_type_list;
 		devpriv->ao_range_type_list[0] =
@@ -330,6 +312,12 @@ static int rti800_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 			(it->options[7] < ARRAY_SIZE(rti800_ao_ranges))
 				? rti800_ao_ranges[it->options[7]]
 				: &range_unknown;
+		s->insn_write	= rti800_ao_insn_write;
+		s->insn_read	= comedi_readback_insn_read;
+
+		ret = comedi_alloc_subdev_readback(s);
+		if (ret)
+			return ret;
 	} else {
 		s->type		= COMEDI_SUBD_UNUSED;
 	}