When updating the output channels make sure the channels configured as inputs stay inputs. Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx> Cc: Ian Abbott <abbotti@xxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/comedi/drivers/pcmuio.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/pcmuio.c b/drivers/staging/comedi/drivers/pcmuio.c index 076a08a..5b0ade2 100644 --- a/drivers/staging/comedi/drivers/pcmuio.c +++ b/drivers/staging/comedi/drivers/pcmuio.c @@ -215,8 +215,14 @@ static int pcmuio_dio_insn_bits(struct comedi_device *dev, s->state &= ~mask; s->state |= (mask & bits); - /* invert the state and update the channels */ + /* + * Invert the state and update the channels. + * + * The s->io_bits mask makes sure inputs are '0' so + * that the output pins stay in a high-z state. + */ val = s->state ^ ((0x1 << s->n_chan) - 1); + val &= s->io_bits; pcmuio_write(dev, val, asic, 0, port); } -- 1.8.3.2 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
