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| author | Narcisa Ana Maria Vasile <narcisaanamaria12@gmail.com> | 2017-12-06 19:57:58 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-08 18:03:44 +0300 |
| commit | 8f114acd4e1a9cfa05b70bcc4219bc88197b5c9b (patch) | |
| tree | 9f8cde7d411bd249c0fdbb0b0c27c442cc1b9346 /drivers/iio/chemical | |
| parent | 9bf94f836e32ea168ec7448a523c11480317ad79 (diff) | |
| download | linux-8f114acd4e1a9cfa05b70bcc4219bc88197b5c9b.tar.xz | |
iio: chemical: ccs811: Fix output of IIO_CONCENTRATION channels
in_concentration_raw should report, according to sysfs-bus-iio documentation,
a "Raw (unscaled no offset etc.) percentage reading of a substance."
Modify scale to convert from ppm/ppb to percentage:
1 ppm = 0.0001%
1 ppb = 0.0000001%
There is no offset needed to convert the ppm/ppb to percentage,
so remove offset from IIO_CONCENTRATION (IIO_MOD_CO2) channel.
Cc'd stable to reduce chance of userspace breakage in the long
run as we fix this wrong bit of ABI usage.
Signed-off-by: Narcisa Ana Maria Vasile <narcisaanamaria12@gmail.com>
Cc: <Stable@vger.kernel.org>
Reviewed-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iio/chemical')
| -rw-r--r-- | drivers/iio/chemical/ccs811.c | 13 |
1 files changed, 3 insertions, 10 deletions
diff --git a/drivers/iio/chemical/ccs811.c b/drivers/iio/chemical/ccs811.c index 97bce8345c6a..fbe2431f5b81 100644 --- a/drivers/iio/chemical/ccs811.c +++ b/drivers/iio/chemical/ccs811.c @@ -96,7 +96,6 @@ static const struct iio_chan_spec ccs811_channels[] = { .channel2 = IIO_MOD_CO2, .modified = 1, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | - BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE), .scan_index = 0, .scan_type = { @@ -255,24 +254,18 @@ static int ccs811_read_raw(struct iio_dev *indio_dev, switch (chan->channel2) { case IIO_MOD_CO2: *val = 0; - *val2 = 12834; + *val2 = 100; return IIO_VAL_INT_PLUS_MICRO; case IIO_MOD_VOC: *val = 0; - *val2 = 84246; - return IIO_VAL_INT_PLUS_MICRO; + *val2 = 100; + return IIO_VAL_INT_PLUS_NANO; default: return -EINVAL; } default: return -EINVAL; } - case IIO_CHAN_INFO_OFFSET: - if (!(chan->type == IIO_CONCENTRATION && - chan->channel2 == IIO_MOD_CO2)) - return -EINVAL; - *val = -400; - return IIO_VAL_INT; default: return -EINVAL; } |