On 2014-04-28 19:53, H Hartley Sweeten wrote:
The analog input async command can use the pacer for the scan_begin_src or the convert_src. The (*do_cmdtest) calculates the divisors when validating the cmd argument.There is no reason to recalc the divisors in the (*do_cmd). Just use the values from the private data. For aesthetics, rename the setup_counters() function so it has namespace associated with the driver. Refactor the function to use the values from the private data and absorb das1800_set_frequency() to clarify the code. This function will not fail so change the return type to void to simplify the (*do_cmd) a bit. Signed-off-by: H Hartley Sweeten <hswee...@visionengravers.com> Cc: Ian Abbott <abbo...@mev.co.uk> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/staging/comedi/drivers/das1800.c | 79 +++++++------------------------- 1 file changed, 16 insertions(+), 63 deletions(-) diff --git a/drivers/staging/comedi/drivers/das1800.c b/drivers/staging/comedi/drivers/das1800.c index 3d5bc8e..a967945 100644 --- a/drivers/staging/comedi/drivers/das1800.c +++ b/drivers/staging/comedi/drivers/das1800.c @@ -962,68 +962,26 @@ static int control_c_bits(const struct comedi_cmd *cmd) return control_c; } -/* loads counters with divisor1, divisor2 from private structure */ -static int das1800_set_frequency(struct comedi_device *dev) +static void das1800_setup_counters(struct comedi_device *dev, + const struct comedi_cmd *cmd) { struct das1800_private *devpriv = dev->private; - int err = 0; - - /* counter 1, mode 2 */ - if (i8254_load(dev->iobase + DAS1800_COUNTER, 0, 1, devpriv->divisor1, - 2)) - err++; - /* counter 2, mode 2 */ - if (i8254_load(dev->iobase + DAS1800_COUNTER, 0, 2, devpriv->divisor2, - 2)) - err++; - if (err) - return -1; - - return 0; -} - -/* sets up counters */ -static int setup_counters(struct comedi_device *dev, - const struct comedi_cmd *cmd) -{ - struct das1800_private *devpriv = dev->private; - unsigned int period; - - /* setup cascaded counters for conversion/scan frequency */ - switch (cmd->scan_begin_src) { - case TRIG_FOLLOW: /* not in burst mode */ - if (cmd->convert_src == TRIG_TIMER) { - /* set conversion frequency */ - period = cmd->convert_arg; - i8253_cascade_ns_to_timer(I8254_OSC_BASE_5MHZ, - &devpriv->divisor1, - &devpriv->divisor2, - &period, cmd->flags); - if (das1800_set_frequency(dev) < 0) - return -1; - } - break; - case TRIG_TIMER: /* in burst mode */ - /* set scan frequency */ - period = cmd->scan_begin_arg; - i8253_cascade_ns_to_timer(I8254_OSC_BASE_5MHZ, - &devpriv->divisor1, - &devpriv->divisor2, - &period, cmd->flags); - if (das1800_set_frequency(dev) < 0) - return -1; - break; - default: - break; - } + unsigned long timer_base = dev->iobase + DAS1800_COUNTER; - /* setup counter 0 for 'about triggering' */ - if (cmd->stop_src == TRIG_EXT) { - /* load counter 0 in mode 0 */ - i8254_load(dev->iobase + DAS1800_COUNTER, 0, 0, 1, 0); + /* setup cascaded counters for conversion/scan frequency */ + if ((cmd->scan_begin_src == TRIG_FOLLOW || + cmd->scan_begin_src == TRIG_TIMER) && + cmd->convert_src == TRIG_TIMER) { + i8254_load(timer_base, 0, + 1, devpriv->divisor1, I8254_MODE2 | I8254_BINARY); + i8254_load(timer_base, 0, + 2, devpriv->divisor2, I8254_MODE2 | I8254_BINARY); }
The mode is wrong.
- return 0; + /* setup counter 0 for 'about triggering' */ + if (cmd->stop_src == TRIG_EXT) + i8254_load(timer_base, 0, + 0, 1, I8254_MODE0 | I8254_BINARY); }
The mode is correct (0), but that's not the way to express it. -- -=( Ian Abbott @ MEV Ltd. E-mail: <abbo...@mev.co.uk> )=- -=( Tel: +44 (0)161 477 1898 FAX: +44 (0)161 718 3587 )=- _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
