For NI M Series cards, the Comedi `insn_read` handler for the AI subdevice is broken due to ANDing the value read from the AI FIFO data register with an incorrect mask. The incorrect mask clears all but the most significant bit of the sample data. It should preserve all the sample data bits. Correct it. Fixes: 817144ae7fda ("staging: comedi: ni_mio_common: remove unnecessary use of 'board->adbits'") Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # 4.7+ --- Needs backporting to stable kernels >= 3.17 --- drivers/staging/comedi/drivers/ni_mio_common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c index 9812508..9543539 100644 --- a/drivers/staging/comedi/drivers/ni_mio_common.c +++ b/drivers/staging/comedi/drivers/ni_mio_common.c @@ -1832,7 +1832,7 @@ static int ni_ai_insn_read(struct comedi_device *dev, unsigned int *data) { struct ni_private *devpriv = dev->private; - unsigned int mask = (s->maxdata + 1) >> 1; + unsigned int mask = s->maxdata; int i, n; unsigned int signbits; unsigned int d; -- 2.10.2 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel