From 0c8fb3867dd3cc191c8de33e79229f629ceb02a2 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Mon, 25 Aug 2014 16:04:49 -0700 Subject: [PATCH] staging: comedi: mf6x4: 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 Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/mf6x4.c | 27 +++++++------------------- 1 file changed, 7 insertions(+), 20 deletions(-) diff --git a/drivers/staging/comedi/drivers/mf6x4.c b/drivers/staging/comedi/drivers/mf6x4.c index 66570558b07e..005376e19517 100644 --- a/drivers/staging/comedi/drivers/mf6x4.c +++ b/drivers/staging/comedi/drivers/mf6x4.c @@ -100,9 +100,6 @@ struct mf6x4_private { * offsets -- this variable makes the access easier */ void __iomem *gpioc_R; - - /* DAC value cache -- used for insn_read function */ - int ao_readback[8]; }; static int mf6x4_di_insn_bits(struct comedi_device *dev, @@ -181,7 +178,7 @@ static int mf6x4_ao_insn_write(struct comedi_device *dev, { struct mf6x4_private *devpriv = dev->private; unsigned int chan = CR_CHAN(insn->chanspec); - unsigned int val = devpriv->ao_readback[chan]; + unsigned int val = s->readback[chan]; uint32_t gpioc; int i; @@ -194,21 +191,7 @@ static int mf6x4_ao_insn_write(struct comedi_device *dev, val = data[i]; iowrite16(val, dev->mmio + MF6X4_DAC_R(chan)); } - devpriv->ao_readback[chan] = val; - - return insn->n; -} - -static int mf6x4_ao_insn_read(struct comedi_device *dev, - struct comedi_subdevice *s, - struct comedi_insn *insn, unsigned int *data) -{ - struct mf6x4_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]; + s->readback[chan] = val; return insn->n; } @@ -276,7 +259,11 @@ static int mf6x4_auto_attach(struct comedi_device *dev, unsigned long context) s->maxdata = 0x3fff; /* 14 bits DAC */ s->range_table = &range_bipolar10; s->insn_write = mf6x4_ao_insn_write; - s->insn_read = mf6x4_ao_insn_read; + s->insn_read = comedi_readback_insn_read; + + ret = comedi_alloc_subdev_readback(s); + if (ret) + return ret; /* DIN */ s = &dev->subdevices[2]; -- 2.39.5