From 73bcf01cb8c57c699c2a194fef3bad9bd39d6e1a Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Tue, 29 Apr 2014 11:08:37 -0700 Subject: [PATCH] staging: comedi: adv_pci1710: only calc the pacer divisors once 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. Save the calculated divisors in the private data as 'next_divisor[12]'. The (*do_cmd) then transfers them to the private data 'divisor[12]' so that they can be used to set the timer for the command immediately or later when the cmd->start_src is TRIG_EXT (mode 2 in this driver). Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/adv_pci1710.c | 25 ++++++++++++------------- 1 file changed, 12 insertions(+), 13 deletions(-) diff --git a/drivers/staging/comedi/drivers/adv_pci1710.c b/drivers/staging/comedi/drivers/adv_pci1710.c index 6bdd915d..7941a3e 100644 --- a/drivers/staging/comedi/drivers/adv_pci1710.c +++ b/drivers/staging/comedi/drivers/adv_pci1710.c @@ -305,7 +305,10 @@ 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 next_divisor1; + unsigned int next_divisor2; + unsigned int divisor1; + unsigned int divisor2; unsigned int act_chanlist[32]; /* list of scanned channel */ unsigned char saved_seglen; /* len of the non-repeating chanlist */ unsigned char da_ranges; /* copy of D/A outpit range register */ @@ -939,7 +942,7 @@ 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; } @@ -955,7 +958,6 @@ 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) { @@ -982,6 +984,9 @@ static int pci171x_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s) if ((cmd->flags & TRIG_WAKE_EOS) == 0) devpriv->CntrlReg |= Control_ONEFH; + devpriv->divisor1 = devpriv->next_divisor1; + devpriv->divisor2 = devpriv->next_divisor2; + switch (mode) { case 1: case 2: @@ -995,17 +1000,11 @@ 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: @@ -1028,7 +1027,6 @@ 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 */ @@ -1078,7 +1076,8 @@ 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->next_divisor1, + &devpriv->next_divisor2, &cmd->convert_arg, cmd->flags); if (cmd->convert_arg < this_board->ai_ns_min) cmd->convert_arg = this_board->ai_ns_min; -- 2.7.4