From bf8e3e3ad467f9e63069d19e56baf40644b7ec03 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Mon, 25 Aug 2014 16:04:42 -0700 Subject: [PATCH] staging: comedi: dmm32at: cleanup dmm32at_ao_winsn() For aesthetics, rename the function and tidy it up a bit. Also rename the registers used by this function and add a macro to set the 'chan' bits in the MSB data register. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/dmm32at.c | 44 +++++++++++------------- 1 file changed, 20 insertions(+), 24 deletions(-) diff --git a/drivers/staging/comedi/drivers/dmm32at.c b/drivers/staging/comedi/drivers/dmm32at.c index e9cd2517ad81..cfe32348ff61 100644 --- a/drivers/staging/comedi/drivers/dmm32at.c +++ b/drivers/staging/comedi/drivers/dmm32at.c @@ -47,9 +47,10 @@ Configuration Options: #define DMM32AT_AILOW 0x02 #define DMM32AT_AIHIGH 0x03 -#define DMM32AT_DACLSB 0x04 #define DMM32AT_DACSTAT 0x04 -#define DMM32AT_DACMSB 0x05 +#define DMM32AT_DACLSB_REG 0x04 +#define DMM32AT_DACMSB_REG 0x05 +#define DMM32AT_DACMSB_CHAN(x) ((x) << 6) #define DMM32AT_FIFOCNTRL 0x07 #define DMM32AT_FIFOSTAT 0x07 @@ -540,42 +541,37 @@ static int dmm32at_ao_eoc(struct comedi_device *dev, return -EBUSY; } -static int dmm32at_ao_winsn(struct comedi_device *dev, - struct comedi_subdevice *s, - struct comedi_insn *insn, unsigned int *data) +static int dmm32at_ao_insn_write(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_insn *insn, + unsigned int *data) { struct dmm32at_private *devpriv = dev->private; - int i; - int chan = CR_CHAN(insn->chanspec); - unsigned char hi, lo, status; + unsigned int chan = CR_CHAN(insn->chanspec); + unsigned int val; int ret; + int i; - /* Writing a list of values to an AO channel is probably not - * very useful, but that's how the interface is defined. */ for (i = 0; i < insn->n; i++) { + val = data[i]; - devpriv->ao_readback[chan] = data[i]; - - /* get the low byte */ - lo = data[i] & 0x00ff; - /* high byte also contains channel number */ - hi = (data[i] >> 8) + chan * (1 << 6); - /* write the low and high values to the board */ - outb(lo, dev->iobase + DMM32AT_DACLSB); - outb(hi, dev->iobase + DMM32AT_DACMSB); + /* write LSB then MSB + chan to load DAC */ + outb(val & 0xff, dev->iobase + DMM32AT_DACLSB_REG); + outb((val >> 8) | DMM32AT_DACMSB_CHAN(chan), + dev->iobase + DMM32AT_DACMSB_REG); /* wait for circuit to settle */ ret = comedi_timeout(dev, s, insn, dmm32at_ao_eoc, 0); if (ret) return ret; - /* dummy read to update trigger the output */ - status = inb(dev->iobase + DMM32AT_DACMSB); + /* dummy read to update DAC */ + inb(dev->iobase + DMM32AT_DACMSB_REG); + devpriv->ao_readback[chan] = val; } - /* return the number of samples read/written */ - return i; + return insn->n; } static int dmm32at_ao_rinsn(struct comedi_device *dev, @@ -764,7 +760,7 @@ static int dmm32at_attach(struct comedi_device *dev, s->n_chan = 4; s->maxdata = 0x0fff; s->range_table = &dmm32at_aoranges; - s->insn_write = dmm32at_ao_winsn; + s->insn_write = dmm32at_ao_insn_write; s->insn_read = dmm32at_ao_rinsn; s = &dev->subdevices[2]; -- 2.34.1