[PATCH 17/22] staging: comedi: adv_pci1710: only calc the pacer divisors once

[H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>]

When the cmd->convert_src == TRIG_TIMER the divisors needed to
generate the pacer time are calculated in the (*do_cmdtest) to
validate the cmd->convert_arg. The core always does the (*do_cmdtest)
before the (*do_cmd) so there is no reason to recalc the divisors.

Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/staging/comedi/drivers/adv_pci1710.c | 20 +++++++-------------
 1 file changed, 7 insertions(+), 13 deletions(-)

diff --git a/drivers/staging/comedi/drivers/adv_pci1710.c b/drivers/staging/comedi/drivers/adv_pci1710.c
index c1aa16a..99e3a30 100644
--- a/drivers/staging/comedi/drivers/adv_pci1710.c
+++ b/drivers/staging/comedi/drivers/adv_pci1710.c
@@ -305,7 +305,8 @@ struct pci1710_private {
 	unsigned char ai_et;
 	unsigned int ai_et_CntrlReg;
 	unsigned int ai_et_MuxVal;
-	unsigned int ai_et_div1, ai_et_div2;
+	unsigned int divisor1;
+	unsigned int divisor2;
 	unsigned int act_chanlist[32];	/*  list of scanned channel */
 	unsigned char act_chanlist_len;	/*  len of scanlist */
 	unsigned char act_chanlist_pos;	/*  actual position in MUX list */
@@ -942,7 +943,7 @@ static irqreturn_t interrupt_service_pci1710(int irq, void *d)
 		outw(devpriv->ai_et_MuxVal, dev->iobase + PCI171x_MUX);
 		outw(devpriv->CntrlReg, dev->iobase + PCI171x_CONTROL);
 		/*  start pacer */
-		start_pacer(dev, 1, devpriv->ai_et_div1, devpriv->ai_et_div2);
+		start_pacer(dev, 1, devpriv->divisor1, devpriv->divisor2);
 		return IRQ_HANDLED;
 	}
 
@@ -958,7 +959,6 @@ static int pci171x_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 {
 	struct pci1710_private *devpriv = dev->private;
 	struct comedi_cmd *cmd = &s->async->cmd;
-	unsigned int divisor1 = 0, divisor2 = 0;
 	int mode;
 
 	if (cmd->convert_src == TRIG_TIMER) {
@@ -998,17 +998,11 @@ static int pci171x_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 		} else {
 			devpriv->ai_et = 0;
 		}
-		i8253_cascade_ns_to_timer(devpriv->i8254_osc_base,
-					  &divisor1, &divisor2,
-					  &cmd->convert_arg,
-					  cmd->flags);
 		outw(devpriv->CntrlReg, dev->iobase + PCI171x_CONTROL);
 		if (mode != 2) {
 			/*  start pacer */
-			start_pacer(dev, mode, divisor1, divisor2);
-		} else {
-			devpriv->ai_et_div1 = divisor1;
-			devpriv->ai_et_div2 = divisor2;
+			start_pacer(dev, mode,
+				    devpriv->divisor1, devpriv->divisor2);
 		}
 		break;
 	case 3:
@@ -1031,7 +1025,6 @@ static int pci171x_ai_cmdtest(struct comedi_device *dev,
 	struct pci1710_private *devpriv = dev->private;
 	int err = 0;
 	int tmp;
-	unsigned int divisor1 = 0, divisor2 = 0;
 
 	/* Step 1 : check if triggers are trivially valid */
 
@@ -1081,7 +1074,8 @@ static int pci171x_ai_cmdtest(struct comedi_device *dev,
 	if (cmd->convert_src == TRIG_TIMER) {
 		tmp = cmd->convert_arg;
 		i8253_cascade_ns_to_timer(devpriv->i8254_osc_base,
-					  &divisor1, &divisor2,
+					  &devpriv->divisor1,
+					  &devpriv->divisor2,
 					  &cmd->convert_arg, cmd->flags);
 		if (cmd->convert_arg < this_board->ai_ns_min)
 			cmd->convert_arg = this_board->ai_ns_min;
-- 
1.9.2

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