staging: comedi: adl_pci9111: cleanup pci9111_ai_munge()

The shift, maxdata, and invert values, used to handle the 12-/16-bit
analog input differences, can be calculated based on the subdevice
maxdata value.

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>
This commit is contained in:
H Hartley Sweeten 2012-09-10 18:54:42 -07:00 committed by Greg Kroah-Hartman
parent 2873ea8154
commit af031edf3f
1 changed files with 7 additions and 13 deletions

View File

@ -809,21 +809,15 @@ static void pci9111_ai_munge(struct comedi_device *dev,
unsigned int num_bytes,
unsigned int start_chan_index)
{
unsigned int i, num_samples = num_bytes / sizeof(short);
short *array = data;
int resolution =
((struct pci9111_board *)dev->board_ptr)->ai_resolution;
unsigned int maxdata = s->maxdata;
unsigned int invert = (maxdata + 1) >> 1;
unsigned int shift = (maxdata == 0xffff) ? 0 : 4;
unsigned int num_samples = num_bytes / sizeof(short);
unsigned int i;
for (i = 0; i < num_samples; i++) {
if (resolution == PCI9111_HR_AI_RESOLUTION)
array[i] =
(array[i] & PCI9111_HR_AI_RESOLUTION_MASK) ^
PCI9111_HR_AI_RESOLUTION_2_CMP_BIT;
else
array[i] =
((array[i] >> 4) & PCI9111_AI_RESOLUTION_MASK) ^
PCI9111_AI_RESOLUTION_2_CMP_BIT;
}
for (i = 0; i < num_samples; i++)
array[i] = ((array[i] >> shift) & maxdata) ^ invert;
}
/* ------------------------------------------------------------------ */