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| author |   Linus Walleij <linus.walleij@linaro.org> | 2021-03-08 11:02:18 +0100 |
|---|---|---|
| committer |   Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2021-03-25 19:13:51 +0000 |
| commit | 635ef601b2387c3215252c9931786524d122c0e7 (patch) | |
| tree | b60132242319a0e98ffafdeef59b4fadd28ecde2 /drivers/iio/inkern.c | |
| parent | iio: xilinx-xadc: Remove code to set trigger parent (diff) | |
| download | linux-dev-635ef601b2387c3215252c9931786524d122c0e7.tar.xz linux-dev-635ef601b2387c3215252c9931786524d122c0e7.zip | |
iio: Provide iio_read_channel_processed_scale() API
Since the old iio_read_channel_processed() would
lose precision if we fall back to reading raw and
scaling, we introduce a new API that will pass in
a scale factor when reading a processed channel:
iio_read_channel_processed_scale().
Refactor iio_read_channel_processed() as a special
case with scale factor 1.
Cc: Peter Rosin <peda@axentia.se>
Cc: Chris Lesiak <chris.lesiak@licor.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: linux-iio@vger.kernel.org
Link: https://lore.kernel.org/linux-iio/20201224011607.1059534-1-linus.walleij@linaro.org/
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210308100219.2732156-1-linus.walleij@linaro.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio/inkern.c')
| -rw-r--r-- | drivers/iio/inkern.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c index db77a2d4a56b..c61fc06f98b8 100644 --- a/drivers/iio/inkern.c +++ b/drivers/iio/inkern.c @@ -688,7 +688,8 @@ int iio_read_channel_offset(struct iio_channel *chan, int *val, int *val2) } EXPORT_SYMBOL_GPL(iio_read_channel_offset); -int iio_read_channel_processed(struct iio_channel *chan, int *val) +int iio_read_channel_processed_scale(struct iio_channel *chan, int *val, + unsigned int scale) { int ret; @@ -701,11 +702,15 @@ int iio_read_channel_processed(struct iio_channel *chan, int *val) if (iio_channel_has_info(chan->channel, IIO_CHAN_INFO_PROCESSED)) { ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_PROCESSED); + if (ret) + goto err_unlock; + *val *= scale; } else { ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW); if (ret < 0) goto err_unlock; - ret = iio_convert_raw_to_processed_unlocked(chan, *val, val, 1); + ret = iio_convert_raw_to_processed_unlocked(chan, *val, val, + scale); } err_unlock: @@ -713,6 +718,13 @@ err_unlock: return ret; } +EXPORT_SYMBOL_GPL(iio_read_channel_processed_scale); + +int iio_read_channel_processed(struct iio_channel *chan, int *val) +{ + /* This is just a special case with scale factor 1 */ + return iio_read_channel_processed_scale(chan, val, 1); +} EXPORT_SYMBOL_GPL(iio_read_channel_processed); int iio_read_channel_scale(struct iio_channel *chan, int *val, int *val2) |