From f8d863e4a9b7c7fefa9a1e743d5c290175e361bc Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Mon, 17 Feb 2014 14:27:37 -0700 Subject: [PATCH] staging: comedi: pcl812: don't calc the timer divisors twice The timer divisors are calculated in the (*do_cmdtest) before the (*do_cmd) is called by the comedi core. Save the values in the private data so they don't need to be recalced. Refactor pcl812_start_pacer() to use the values from the private data. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/pcl812.c | 34 ++++++++++--------------- 1 file changed, 14 insertions(+), 20 deletions(-) diff --git a/drivers/staging/comedi/drivers/pcl812.c b/drivers/staging/comedi/drivers/pcl812.c index b34814da34a..0d7d3ae9951 100644 --- a/drivers/staging/comedi/drivers/pcl812.c +++ b/drivers/staging/comedi/drivers/pcl812.c @@ -529,6 +529,8 @@ struct pcl812_private { unsigned int last_dma_run; /* how many bytes to transfer on last DMA buffer */ unsigned int max_812_ai_mode0_rangewait; /* setling time for gain */ unsigned int ao_readback[2]; /* data for AO readback */ + unsigned int divisor1; + unsigned int divisor2; }; static void setup_range_channel(struct comedi_device *dev, @@ -537,9 +539,9 @@ static void setup_range_channel(struct comedi_device *dev, static int pcl812_ai_cancel(struct comedi_device *dev, struct comedi_subdevice *s); -static void pcl812_start_pacer(struct comedi_device *dev, bool load_timers, - unsigned int divisor1, unsigned int divisor2) +static void pcl812_start_pacer(struct comedi_device *dev, bool load_timers) { + struct pcl812_private *devpriv = dev->private; unsigned long timer_base = dev->iobase + PCL812_TIMER_BASE; i8254_set_mode(timer_base, 0, 2, I8254_MODE2 | I8254_BINARY); @@ -547,8 +549,8 @@ static void pcl812_start_pacer(struct comedi_device *dev, bool load_timers, udelay(1); if (load_timers) { - i8254_write(timer_base, 0, 2, divisor2); - i8254_write(timer_base, 0, 1, divisor1); + i8254_write(timer_base, 0, 2, devpriv->divisor2); + i8254_write(timer_base, 0, 1, devpriv->divisor1); } } @@ -687,7 +689,7 @@ static int pcl812_ai_cmdtest(struct comedi_device *dev, struct pcl812_private *devpriv = dev->private; int err = 0; unsigned int flags; - int tmp, divisor1, divisor2; + int tmp; /* Step 1 : check if triggers are trivially valid */ @@ -743,7 +745,8 @@ static int pcl812_ai_cmdtest(struct comedi_device *dev, if (cmd->convert_src == TRIG_TIMER) { tmp = cmd->convert_arg; i8253_cascade_ns_to_timer(I8254_OSC_BASE_2MHZ, - &divisor1, &divisor2, + &devpriv->divisor1, + &devpriv->divisor2, &cmd->convert_arg, cmd->flags); if (cmd->convert_arg < board->ai_ns_min) cmd->convert_arg = board->ai_ns_min; @@ -762,20 +765,11 @@ static int pcl812_ai_cmdtest(struct comedi_device *dev, */ static int pcl812_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s) { - const struct pcl812_board *board = comedi_board(dev); struct pcl812_private *devpriv = dev->private; - unsigned int divisor1 = 0, divisor2 = 0, i, dma_flags, bytes; struct comedi_cmd *cmd = &s->async->cmd; + unsigned int i, dma_flags, bytes; - if (cmd->convert_src == TRIG_TIMER) { - if (cmd->convert_arg < board->ai_ns_min) - cmd->convert_arg = board->ai_ns_min; - i8253_cascade_ns_to_timer(I8254_OSC_BASE_2MHZ, - &divisor1, &divisor2, - &cmd->convert_arg, cmd->flags); - } - - pcl812_start_pacer(dev, false, 0, 0); + pcl812_start_pacer(dev, false); memcpy(devpriv->ai_chanlist, cmd->chanlist, sizeof(unsigned int) * cmd->scan_end_arg); @@ -869,7 +863,7 @@ static int pcl812_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s) switch (cmd->convert_src) { case TRIG_TIMER: - pcl812_start_pacer(dev, true, divisor1, divisor2); + pcl812_start_pacer(dev, true); break; } @@ -1154,7 +1148,7 @@ static int pcl812_ai_cancel(struct comedi_device *dev, outb(0, dev->iobase + PCL812_CLRINT); /* clear INT request */ /* Stop A/D */ outb(devpriv->mode_reg_int | 0, dev->iobase + PCL812_MODE); - pcl812_start_pacer(dev, false, 0, 0); + pcl812_start_pacer(dev, false); outb(0, dev->iobase + PCL812_CLRINT); /* clear INT request */ return 0; } @@ -1182,7 +1176,7 @@ static void pcl812_reset(struct comedi_device *dev) case boardA821: outb(0, dev->iobase + PCL812_DA1_LO); outb(0, dev->iobase + PCL812_DA1_HI); - pcl812_start_pacer(dev, false, 0, 0); + pcl812_start_pacer(dev, false); outb(0, dev->iobase + PCL812_DO_HI); outb(0, dev->iobase + PCL812_DO_LO); outb(devpriv->mode_reg_int | 0, dev->iobase + PCL812_MODE); -- 2.46.0