From 843681c8835bcf4e02f993beae65e356a01d0111 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Fri, 8 Apr 2016 12:41:48 -0700 Subject: [PATCH] staging: comedi: das1800: introduce das1800_ai_chanspec_bits() Introduce a helper function for the common code needed to set the control c register bits for a channel specification. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/das1800.c | 47 +++++++++++++++----------------- 1 file changed, 22 insertions(+), 25 deletions(-) diff --git a/drivers/staging/comedi/drivers/das1800.c b/drivers/staging/comedi/drivers/das1800.c index 64b5403..5694bdb 100644 --- a/drivers/staging/comedi/drivers/das1800.c +++ b/drivers/staging/comedi/drivers/das1800.c @@ -749,25 +749,32 @@ static int control_a_bits(const struct comedi_cmd *cmd) return control_a; } -/* returns appropriate bits for control register c, depending on command */ -static int control_c_bits(struct comedi_subdevice *s, - const struct comedi_cmd *cmd) +static unsigned char das1800_ai_chanspec_bits(struct comedi_subdevice *s, + unsigned int chanspec) { - unsigned int range = CR_RANGE(cmd->chanlist[0]); - unsigned int aref = CR_AREF(cmd->chanlist[0]); - int control_c; + unsigned int range = CR_RANGE(chanspec); + unsigned int aref = CR_AREF(chanspec); + unsigned char bits; - /* set clock source to internal or external, select analog reference, - * select unipolar / bipolar - */ - control_c = UQEN; /* enable upper qram addresses */ + bits = UQEN; if (aref != AREF_DIFF) - control_c |= SD; + bits |= SD; if (aref == AREF_COMMON) - control_c |= CMEN; + bits |= CMEN; if (comedi_range_is_unipolar(s, range)) - control_c |= UB; + bits |= UB; + + return bits; +} + +static int control_c_bits(struct comedi_subdevice *s, + const struct comedi_cmd *cmd) +{ + int control_c; + control_c = das1800_ai_chanspec_bits(s, cmd->chanlist[0]); + + /* set clock source to internal or external */ switch (cmd->scan_begin_src) { case TRIG_FOLLOW: /* not in burst mode */ switch (cmd->convert_src) { @@ -955,25 +962,15 @@ static int das1800_ai_insn_read(struct comedi_device *dev, { unsigned int chan = CR_CHAN(insn->chanspec); unsigned int range = CR_RANGE(insn->chanspec); - unsigned int aref = CR_AREF(insn->chanspec); bool is_unipolar = comedi_range_is_unipolar(s, range); int i, n; int chan_range; int timeout = 1000; unsigned short dpnt; - int conv_flags = 0; unsigned long irq_flags; - /* set up analog reference and unipolar / bipolar mode */ - conv_flags |= UQEN; - if (aref != AREF_DIFF) - conv_flags |= SD; - if (aref == AREF_COMMON) - conv_flags |= CMEN; - if (is_unipolar) - conv_flags |= UB; - - outb(conv_flags, dev->iobase + DAS1800_CONTROL_C); /* software conversion enabled */ + outb(das1800_ai_chanspec_bits(s, insn->chanspec), + dev->iobase + DAS1800_CONTROL_C); /* software pacer */ outb(CVEN, dev->iobase + DAS1800_STATUS); /* enable conversions */ outb(0x0, dev->iobase + DAS1800_CONTROL_A); /* reset fifo */ outb(FFEN, dev->iobase + DAS1800_CONTROL_A); -- 2.7.4