staging: comedi: core: introduce comedi_chan_range_is_{bi,uni}polar()

Introduce two helper functions to check if a subdevice range_table_list
for a given channel/range is bipolar or unipolar.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h
index bec2276..6db099b 100644 (file)
--- a/drivers/staging/comedi/comedidev.h
+++ b/drivers/staging/comedi/comedidev.h
@@ -307,6 +307,20 @@ static inline bool comedi_range_is_unipolar(struct comedi_subdevice *s,
        return s->range_table->range[range].min >= 0;
 }
 
+static inline bool comedi_chan_range_is_bipolar(struct comedi_subdevice *s,
+                                               unsigned int chan,
+                                               unsigned int range)
+{
+       return s->range_table_list[chan]->range[range].min < 0;
+}
+
+static inline bool comedi_chan_range_is_unipolar(struct comedi_subdevice *s,
+                                                unsigned int chan,
+                                                unsigned int range)
+{
+       return s->range_table_list[chan]->range[range].min >= 0;
+}
+
 /* munge between offset binary and two's complement values */
 static inline unsigned int comedi_offset_munge(struct comedi_subdevice *s,
                                               unsigned int val)