iio: ti_am335x_adc: Fix: Use same step id at FIFOs both ends

commit baa3c65298c089a9014b4e523a14ec2885cca1bc upstream.

Since AI lines could be selected at will (linux-3.11) the sending
and receiving ends of the FIFO does not agree about what step is used
for a line. It only works if the last lines are used, like 5,6,7,
and fails if ie 2,4,6 is selected in DT.

Signed-off-by: Jan Kardell <jan.kardell@telliq.com>
Tested-by: Zubair Lutfullah <zubair.lutfullah@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index 31e786e..63b2bb6 100644 (file)
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -375,7 +375,7 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
                        return -EAGAIN;
                }
        }
-       map_val = chan->channel + TOTAL_CHANNELS;
+       map_val = adc_dev->channel_step[chan->scan_index];
 
        /*
         * We check the complete FIFO. We programmed just one entry but in case