staging: comedi: adl_pci9111: cleanup pci9111_ai_munge()
authorH Hartley Sweeten <hartleys@visionengravers.com>
Tue, 11 Sep 2012 01:54:42 +0000 (18:54 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 11 Sep 2012 03:02:24 +0000 (20:02 -0700)
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>
drivers/staging/comedi/drivers/adl_pci9111.c

index 1f32a265ef800fce19d96c1a44f8d315f640556b..3d7e7209c1997c2e3ab7d9e8e161e121f5030d84 100644 (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;
-
-       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;
-       }
+       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++)
+               array[i] = ((array[i] >> shift) & maxdata) ^ invert;
 }
 
 /*  ------------------------------------------------------------------ */