All of the comedi drivers that support the 'cmd' callback also
require a 'do_cmdtest' callback. The do_cmdtest validates the
comedi_cmd before it is executed.
"Step 1" of each do_cmdtest does a trivial validation of the
trigger sources by doing something like this for each trigger:
int err = 0;
unsigned int tmp;
tmp = cmd->start_src;
src &= TRIG_NOW;
if (!src || tmp != src)
err++;
/* Test the remaining triggers similarly */
if (err)
return 1;
Introduce a helper function in comedi_fc to handle this boilerplate.
The drivers can then just do:
err |= cfc_check_trigger_src(&cmd->start_src, TRIG_NOW);
/* Test the remaining triggers similarly */
if (err)
return 1;
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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