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| author | Linus Walleij <linus.walleij@linaro.org> | 2023-09-02 22:46:20 +0300 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2023-10-17 22:25:32 +0300 |
| commit | bee448390e5166d019e9e037194d487ee94399d9 (patch) | |
| tree | 6b9fcdef57d782ec83797f40f87f4c082cb7ea42 /drivers/iio | |
| parent | 865b080e3229102f160889328ce2e8e97aa65ea0 (diff) | |
| download | linux-bee448390e5166d019e9e037194d487ee94399d9.tar.xz | |
iio: afe: rescale: Accept only offset channels
As noted by Jonathan Cameron: it is perfectly legal for a channel
to have an offset but no scale in addition to the raw interface.
The conversion will imply that scale is 1:1.
Make rescale_configure_channel() accept just scale, or just offset
to process a channel.
When a user asks for IIO_CHAN_INFO_OFFSET in rescale_read_raw()
we now have to deal with the fact that OFFSET could be present
but SCALE missing. Add code to simply scale 1:1 in this case.
Link: https://lore.kernel.org/linux-iio/CACRpkdZXBjHU4t-GVOCFxRO-AHGxKnxMeHD2s4Y4PuC29gBq6g@mail.gmail.com/
Fixes: 53ebee949980 ("iio: afe: iio-rescale: Support processed channels")
Fixes: 9decacd8b3a4 ("iio: afe: rescale: Fix boolean logic bug")
Reported-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Peter Rosin <peda@axentia.se>
Link: https://lore.kernel.org/r/20230902-iio-rescale-only-offset-v2-1-988b807754c8@linaro.org
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio')
| -rw-r--r-- | drivers/iio/afe/iio-rescale.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/drivers/iio/afe/iio-rescale.c b/drivers/iio/afe/iio-rescale.c index 1f280c360701..56e5913ab82d 100644 --- a/drivers/iio/afe/iio-rescale.c +++ b/drivers/iio/afe/iio-rescale.c @@ -214,8 +214,18 @@ static int rescale_read_raw(struct iio_dev *indio_dev, return ret < 0 ? ret : -EOPNOTSUPP; } - ret = iio_read_channel_scale(rescale->source, &scale, &scale2); - return rescale_process_offset(rescale, ret, scale, scale2, + if (iio_channel_has_info(rescale->source->channel, + IIO_CHAN_INFO_SCALE)) { + ret = iio_read_channel_scale(rescale->source, &scale, &scale2); + return rescale_process_offset(rescale, ret, scale, scale2, + schan_off, val, val2); + } + + /* + * If we get here we have no scale so scale 1:1 but apply + * rescaler and offset, if any. + */ + return rescale_process_offset(rescale, IIO_VAL_FRACTIONAL, 1, 1, schan_off, val, val2); default: return -EINVAL; @@ -280,8 +290,9 @@ static int rescale_configure_channel(struct device *dev, chan->type = rescale->cfg->type; if (iio_channel_has_info(schan, IIO_CHAN_INFO_RAW) && - iio_channel_has_info(schan, IIO_CHAN_INFO_SCALE)) { - dev_info(dev, "using raw+scale source channel\n"); + (iio_channel_has_info(schan, IIO_CHAN_INFO_SCALE) || + iio_channel_has_info(schan, IIO_CHAN_INFO_OFFSET))) { + dev_info(dev, "using raw+scale/offset source channel\n"); } else if (iio_channel_has_info(schan, IIO_CHAN_INFO_PROCESSED)) { dev_info(dev, "using processed channel\n"); rescale->chan_processed = true; |