From 8fbf1f4569634e950c1ebc46b0bad612ea404b00 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Fri, 20 Sep 2013 16:44:08 -0700 Subject: [PATCH] staging: comedi: pcl711: no need to calc the timer values twice The comedi core always calls the (*do_cmdtest) function to validate a command before it calls the (*do_cmd) function. Since the (*do_cmdtest) has already calculated the timer values in order to validate the cmd->scan_begin_arg there is no reason to recalc the values in the (*do_cmd). This also fixes a bug in the driver. The (*do_cmdtest) was using a time base value of 100 and but the (*do_cmd) was using a time base of 500. These result in different timer values. The functions used to calculate the values are actually the same due to a #define in the 8253.h header. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/pcl711.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) diff --git a/drivers/staging/comedi/drivers/pcl711.c b/drivers/staging/comedi/drivers/pcl711.c index 8f068eb..60b7137 100644 --- a/drivers/staging/comedi/drivers/pcl711.c +++ b/drivers/staging/comedi/drivers/pcl711.c @@ -331,7 +331,6 @@ static int pcl711_ai_cmdtest(struct comedi_device *dev, err |= cfc_check_trigger_arg_is(&cmd->scan_begin_arg, 0); } else { #define MAX_SPEED 1000 -#define TIMER_BASE 100 err |= cfc_check_trigger_arg_min(&cmd->scan_begin_arg, MAX_SPEED); } @@ -352,11 +351,11 @@ static int pcl711_ai_cmdtest(struct comedi_device *dev, if (cmd->scan_begin_src == TRIG_TIMER) { tmp = cmd->scan_begin_arg; - i8253_cascade_ns_to_timer_2div(TIMER_BASE, - &devpriv->divisor1, - &devpriv->divisor2, - &cmd->scan_begin_arg, - cmd->flags & TRIG_ROUND_MASK); + i8253_cascade_ns_to_timer(500, /* 2 Mhz */ + &devpriv->divisor1, + &devpriv->divisor2, + &cmd->scan_begin_arg, + cmd->flags & TRIG_ROUND_MASK); if (tmp != cmd->scan_begin_arg) err++; } @@ -369,22 +368,16 @@ static int pcl711_ai_cmdtest(struct comedi_device *dev, static int pcl711_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s) { - int timer1, timer2; + struct pcl711_private *devpriv = dev->private; struct comedi_cmd *cmd = &s->async->cmd; pcl711_set_changain(dev, s, cmd->chanlist[0]); if (cmd->scan_begin_src == TRIG_TIMER) { - timer1 = timer2 = 0; - i8253_cascade_ns_to_timer(500, /* 2 Mhz */ - &timer1, &timer2, - &cmd->scan_begin_arg, - TRIG_ROUND_NEAREST); - i8254_load(dev->iobase + PCL711_TIMER_BASE, 0, - 1, timer1, I8254_MODE2 | I8254_BINARY); + 1, devpriv->divisor1, I8254_MODE2 | I8254_BINARY); i8254_load(dev->iobase + PCL711_TIMER_BASE, 0, - 2, timer2, I8254_MODE2 | I8254_BINARY); + 2, devpriv->divisor2, I8254_MODE2 | I8254_BINARY); /* clear pending interrupts (just in case) */ outb(0, dev->iobase + PCL711_CLRINTR); -- 2.7.4