From 45b6937ac647f18913f6d1fb07601b97f78647c5 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Tue, 26 Mar 2013 14:58:49 -0700 Subject: [PATCH] staging: comedi: rtd520: cleanup rtd_dio_insn_bits() Add some local variables to make this function a bit cleaner and remove the unnecessary comments. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/rtd520.c | 27 ++++++++------------------- 1 file changed, 8 insertions(+), 19 deletions(-) diff --git a/drivers/staging/comedi/drivers/rtd520.c b/drivers/staging/comedi/drivers/rtd520.c index f98ec14..bfe3832 100644 --- a/drivers/staging/comedi/drivers/rtd520.c +++ b/drivers/staging/comedi/drivers/rtd520.c @@ -1128,33 +1128,22 @@ static int rtd_ao_rinsn(struct comedi_device *dev, return i; } -/* - Write a masked set of bits and the read back the port. - We track what the bits should be (i.e. we don't read the port first). - - DIO devices are slightly special. Although it is possible to - * implement the insn_read/insn_write interface, it is much more - * useful to applications if you implement the insn_bits interface. - * This allows packed reading/writing of the DIO channels. The - * comedi core can convert between insn_bits and insn_read/write - */ static int rtd_dio_insn_bits(struct comedi_device *dev, struct comedi_subdevice *s, - struct comedi_insn *insn, unsigned int *data) + struct comedi_insn *insn, + unsigned int *data) { struct rtdPrivate *devpriv = dev->private; + unsigned int mask = data[0]; + unsigned int bits = data[1]; - /* The insn data is a mask in data[0] and the new data - * in data[1], each channel cooresponding to a bit. */ - if (data[0]) { - s->state &= ~data[0]; - s->state |= data[0] & data[1]; + if (mask) { + s->state &= ~mask; + s->state |= (bits & mask); - /* Write out the new digital output lines */ writew(s->state & 0xff, devpriv->las0 + LAS0_DIO0); } - /* on return, data[1] contains the value of the digital - * input lines. */ + data[1] = readw(devpriv->las0 + LAS0_DIO0) & 0xff; return insn->n; -- 2.7.4