pcm_common.c

Go to the documentation of this file.

#include "../comedidev.h"

#include "comedi_fc.h"
#include "pcm_common.h"

int comedi_pcm_cmdtest(struct comedi_device *dev,
               struct comedi_subdevice *s, struct comedi_cmd *cmd)
{
    int err = 0;

    /* Step 1 : check if triggers are trivially valid */

    err |= cfc_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_INT);
    err |= cfc_check_trigger_src(&cmd->scan_begin_src, TRIG_EXT);
    err |= cfc_check_trigger_src(&cmd->convert_src, TRIG_NOW);
    err |= cfc_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
    err |= cfc_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);

    if (err)
        return 1;

    /* Step 2a : make sure trigger sources are unique */

    err |= cfc_check_trigger_is_unique(cmd->start_src);
    err |= cfc_check_trigger_is_unique(cmd->stop_src);

    /* Step 2b : and mutually compatible */

    if (err)
        return 2;

    /* step 3: make sure arguments are trivially compatible */

    /* cmd->start_src == TRIG_NOW || cmd->start_src == TRIG_INT */
    if (cmd->start_arg != 0) {
        cmd->start_arg = 0;
        err++;
    }

    /* cmd->scan_begin_src == TRIG_EXT */
    if (cmd->scan_begin_arg != 0) {
        cmd->scan_begin_arg = 0;
        err++;
    }

    /* cmd->convert_src == TRIG_NOW */
    if (cmd->convert_arg != 0) {
        cmd->convert_arg = 0;
        err++;
    }

    /* cmd->scan_end_src == TRIG_COUNT */
    if (cmd->scan_end_arg != cmd->chanlist_len) {
        cmd->scan_end_arg = cmd->chanlist_len;
        err++;
    }

    switch (cmd->stop_src) {
    case TRIG_COUNT:
        /* any count allowed */
        break;
    case TRIG_NONE:
        if (cmd->stop_arg != 0) {
            cmd->stop_arg = 0;
            err++;
        }
        break;
    default:
        break;
    }

    if (err)
        return 3;

    /* step 4: fix up any arguments */

    /* if (err) return 4; */

    return 0;
}
EXPORT_SYMBOL(comedi_pcm_cmdtest);

MODULE_AUTHOR("Comedi http://www.comedi.org");
MODULE_DESCRIPTION("Comedi low-level driver");
MODULE_LICENSE("GPL");