staging: comedi: remove thisboard macro in the comedi_test driver

The 'thisboard' macro depends on having a local variable with
a magic name. The CodingStyle document suggests not doing this
to avoid confusion. Remove the macro and use the comedi_board()
inline helper to get the dev->board_ptr information.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Mori Hess <fmhess@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/comedi_test.c

@@ -67,8 +67,6 @@ struct waveform_board {
 
 #define N_CHANS 8
 
-#define thisboard ((const struct waveform_board *)dev->board_ptr)
-
 /* Data unique to this driver */
 struct waveform_private {
 	struct timer_list timer;
@@ -429,12 +427,13 @@ static int waveform_ao_insn_write(struct comedi_device *dev,
 static int waveform_attach(struct comedi_device *dev,
 			   struct comedi_devconfig *it)
 {
+	const struct waveform_board *board = comedi_board(dev);
 	struct comedi_subdevice *s;
 	int amplitude = it->options[0];
 	int period = it->options[1];
 	int i;
 
-	dev->board_name = thisboard->name;
+	dev->board_name = board->name;
 
 	if (alloc_private(dev, sizeof(struct waveform_private)) < 0)
 		return -ENOMEM;
@@ -457,8 +456,8 @@ static int waveform_attach(struct comedi_device *dev,
 	/* analog input subdevice */
 	s->type = COMEDI_SUBD_AI;
 	s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_CMD_READ;
-	s->n_chan = thisboard->ai_chans;
-	s->maxdata = (1 << thisboard->ai_bits) - 1;
+	s->n_chan = board->ai_chans;
+	s->maxdata = (1 << board->ai_bits) - 1;
 	s->range_table = &waveform_ai_ranges;
 	s->len_chanlist = s->n_chan * 2;
 	s->insn_read = waveform_ai_insn_read;
@@ -471,8 +470,8 @@ static int waveform_attach(struct comedi_device *dev,
 	/* analog output subdevice (loopback) */
 	s->type = COMEDI_SUBD_AO;
 	s->subdev_flags = SDF_WRITEABLE | SDF_GROUND;
-	s->n_chan = thisboard->ai_chans;
-	s->maxdata = (1 << thisboard->ai_bits) - 1;
+	s->n_chan = board->ai_chans;
+	s->maxdata = (1 << board->ai_bits) - 1;
 	s->range_table = &waveform_ai_ranges;
 	s->len_chanlist = s->n_chan * 2;
 	s->insn_write = waveform_ao_insn_write;