This is a note to let you know that I've just added the patch titled iio: chemical: ccs811: Fix output of IIO_CONCENTRATION channels to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: iio-chemical-ccs811-fix-output-of-iio_concentration-channels.patch and it can be found in the queue-4.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 8f114acd4e1a9cfa05b70bcc4219bc88197b5c9b Mon Sep 17 00:00:00 2001 From: Narcisa Ana Maria Vasile <narcisaanamaria12@xxxxxxxxx> Date: Wed, 6 Dec 2017 18:57:58 +0200 Subject: iio: chemical: ccs811: Fix output of IIO_CONCENTRATION channels From: Narcisa Ana Maria Vasile <narcisaanamaria12@xxxxxxxxx> commit 8f114acd4e1a9cfa05b70bcc4219bc88197b5c9b upstream. 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@xxxxxxxxx> Reviewed-by: Matt Ranostay <matt.ranostay@xxxxxxxxxxxx> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iio/chemical/ccs811.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) --- a/drivers/iio/chemical/ccs811.c +++ b/drivers/iio/chemical/ccs811.c @@ -96,7 +96,6 @@ static const struct iio_chan_spec ccs811 .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_de 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; } Patches currently in stable-queue which might be from narcisaanamaria12@xxxxxxxxx are queue-4.15/iio-chemical-ccs811-fix-output-of-iio_concentration-channels.patch