ni_write_caldac() checks the boardinfo 'caldac' array to determine what caldac is used for a given 'addr'. It then calculates the 'bitstring' and number of 'bits' used to write a value to that caldac address.
After checking the caldac array, if the number of bits is 0 there is no caldac associated with the address. If this happens we shouldn't try writing to the non-existing caldac. Reported-by: coverity (CID 1192116) Signed-off-by: H Hartley Sweeten <hswee...@visionengravers.com> Cc: Ian Abbott <abbo...@mev.co.uk> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/staging/comedi/drivers/ni_mio_common.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c index c66affd9..69d71f3 100644 --- a/drivers/staging/comedi/drivers/ni_mio_common.c +++ b/drivers/staging/comedi/drivers/ni_mio_common.c @@ -4355,6 +4355,10 @@ static void ni_write_caldac(struct comedi_device *dev, int addr, int val) addr -= caldacs[type].n_chans; } + /* bits will be 0 if there is no caldac for the given addr */ + if (bits == 0) + return; + for (bit = 1 << (bits - 1); bit; bit >>= 1) { ni_writeb(dev, ((bit & bitstring) ? 0x02 : 0), Serial_Command); udelay(1); -- 2.3.0 _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel