Introduce a helper function to program the mux and gain for analog input
single channel (*insn_read) and multi-channel (*do_cmd) operations.
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/das16.c | 54 +++++++++++++++++++---------------
1 file changed, 30 insertions(+), 24 deletions(-)
diff --git a/drivers/staging/comedi/drivers/das16.c b/drivers/staging/comedi/drivers/das16.c
index 86e90d5..2c20311 100644
--- a/drivers/staging/comedi/drivers/das16.c
+++ b/drivers/staging/comedi/drivers/das16.c
@@ -537,6 +537,29 @@ static void das16_timer_interrupt(unsigned long arg)
spin_unlock_irqrestore(&dev->spinlock, flags);
}
+static void das16_ai_set_mux_range(struct comedi_device *dev,
+ unsigned int first_chan,
+ unsigned int last_chan,
+ unsigned int range)
+{
+ const struct das16_board *board = dev->board_ptr;
+
+ /* set multiplexer */
+ outb(first_chan | (last_chan << 4), dev->iobase + DAS16_MUX_REG);
+
+ /* some boards do not have programmable gain */
+ if (board->ai_pg == das16_pg_none)
+ return;
+
+ /*
+ * Set gain (this is also burst rate register but according to
+ * computer boards manual, burst rate does nothing, even on
+ * keithley cards).
+ */
+ outb((das16_gainlists[board->ai_pg])[range],
+ dev->iobase + DAS16_GAIN_REG);
+}
+
static int das16_ai_check_chanlist(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_cmd *cmd)
@@ -687,14 +710,15 @@ static unsigned int das16_set_pacer(struct comedi_device *dev, unsigned int ns,
static int das16_cmd_exec(struct comedi_device *dev, struct comedi_subdevice *s)
{
- const struct das16_board *board = dev->board_ptr;
struct das16_private_struct *devpriv = dev->private;
struct comedi_isadma *dma = devpriv->dma;
struct comedi_async *async = s->async;
struct comedi_cmd *cmd = &async->cmd;
+ unsigned int first_chan = CR_CHAN(cmd->chanlist[0]);
+ unsigned int last_chan = CR_CHAN(cmd->chanlist[cmd->chanlist_len - 1]);
+ unsigned int range = CR_RANGE(cmd->chanlist[0]);
unsigned int byte;
unsigned long flags;
- int range;
if (cmd->flags & CMDF_PRIORITY) {
dev_err(dev->class_dev,
@@ -705,19 +729,8 @@ static int das16_cmd_exec(struct comedi_device *dev, struct comedi_subdevice *s)
if (devpriv->can_burst)
outb(DAS1600_CONV_DISABLE, dev->iobase + DAS1600_CONV_REG);
- /* set scan limits */
- byte = CR_CHAN(cmd->chanlist[0]);
- byte |= CR_CHAN(cmd->chanlist[cmd->chanlist_len - 1]) << 4;
- outb(byte, dev->iobase + DAS16_MUX_REG);
-
- /* set gain (this is also burst rate register but according to
- * computer boards manual, burst rate does nothing, even on
- * keithley cards) */
- if (board->ai_pg != das16_pg_none) {
- range = CR_RANGE(cmd->chanlist[0]);
- outb((das16_gainlists[board->ai_pg])[range],
- dev->iobase + DAS16_GAIN_REG);
- }
+ /* set mux and range for chanlist scan */
+ das16_ai_set_mux_range(dev, first_chan, last_chan, range);
/* set counter mode and counts */
cmd->convert_arg = das16_set_pacer(dev, cmd->convert_arg, cmd->flags);
@@ -826,21 +839,14 @@ static int das16_ai_insn_read(struct comedi_device *dev,
struct comedi_insn *insn,
unsigned int *data)
{
- const struct das16_board *board = dev->board_ptr;
unsigned int chan = CR_CHAN(insn->chanspec);
unsigned int range = CR_RANGE(insn->chanspec);
unsigned int val;
int ret;
int i;
- /* set multiplexer */
- outb(chan | (chan << 4), dev->iobase + DAS16_MUX_REG);
-
- /* set gain */
- if (board->ai_pg != das16_pg_none) {
- outb((das16_gainlists[board->ai_pg])[range],
- dev->iobase + DAS16_GAIN_REG);
- }
+ /* set mux and range for single channel */
+ das16_ai_set_mux_range(dev, chan, chan, range);
for (i = 0; i < insn->n; i++) {
/* trigger conversion */
--
2.0.3
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