| Message ID | 20220108205319.2046348-1-liambeguin@gmail.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | iio: afe: add temperature rescaling support | expand |
On Sat, Jan 8, 2022 at 10:53 PM Liam Beguin <liambeguin@gmail.com> wrote: > > Jonathan, Peter, Andy, > > I left out IIO_VAL_INT overflows for now, so that I can focus on getting > the rest of these changes pulled in, but I don't mind adding a patch for > that later on. > > This series focuses on adding temperature rescaling support to the IIO > Analog Front End (AFE) driver. > > The first few patches address minor bugs in IIO inkernel functions, and > prepare the AFE driver for the additional features. > > The main changes to the AFE driver include an initial Kunit test suite, > support for IIO_VAL_INT_PLUS_{NANO,MICRO} scales, and support for RTDs > and temperature transducer sensors. > > My apologies Andy for misunderstanding your left-shift comments, I don't > know where my head was at... Thanks for your patience! For the patches 1-5 Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Jonathan, perhaps you may apply them, so Liam will have less burden in the near future.
On Sun, 9 Jan 2022 15:10:36 +0200 Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > On Sat, Jan 8, 2022 at 10:53 PM Liam Beguin <liambeguin@gmail.com> wrote: > > > > Jonathan, Peter, Andy, > > > > I left out IIO_VAL_INT overflows for now, so that I can focus on getting > > the rest of these changes pulled in, but I don't mind adding a patch for > > that later on. > > > > This series focuses on adding temperature rescaling support to the IIO > > Analog Front End (AFE) driver. > > > > The first few patches address minor bugs in IIO inkernel functions, and > > prepare the AFE driver for the additional features. > > > > The main changes to the AFE driver include an initial Kunit test suite, > > support for IIO_VAL_INT_PLUS_{NANO,MICRO} scales, and support for RTDs > > and temperature transducer sensors. > > > > My apologies Andy for misunderstanding your left-shift comments, I don't > > know where my head was at... Thanks for your patience! > > For the patches 1-5 > Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> > > Jonathan, perhaps you may apply them, so Liam will have less burden in > the near future. > done, Patches 1-5 applied to the togreg branch of iio.git and pushed out as testing for 0-day to see if it can find anything we missed. I've marked the fixes for stable, but am taking these the slow way (via next merge window) so as to keep things simple for applying the rest of the series later this cycle. I got a bit lost in the discussion but seems there are some minor requests for changes so I guess I'll see a v13 of patches 6-12. Thanks, Jonathan
On Sun, 30 Jan 2022 14:39:33 +0000 Jonathan Cameron <jic23@kernel.org> wrote: > On Sun, 9 Jan 2022 15:10:36 +0200 > Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > > > On Sat, Jan 8, 2022 at 10:53 PM Liam Beguin <liambeguin@gmail.com> wrote: > > > > > > Jonathan, Peter, Andy, > > > > > > I left out IIO_VAL_INT overflows for now, so that I can focus on getting > > > the rest of these changes pulled in, but I don't mind adding a patch for > > > that later on. > > > > > > This series focuses on adding temperature rescaling support to the IIO > > > Analog Front End (AFE) driver. > > > > > > The first few patches address minor bugs in IIO inkernel functions, and > > > prepare the AFE driver for the additional features. > > > > > > The main changes to the AFE driver include an initial Kunit test suite, > > > support for IIO_VAL_INT_PLUS_{NANO,MICRO} scales, and support for RTDs > > > and temperature transducer sensors. > > > > > > My apologies Andy for misunderstanding your left-shift comments, I don't > > > know where my head was at... Thanks for your patience! > > > > For the patches 1-5 > > Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> > > > > Jonathan, perhaps you may apply them, so Liam will have less burden in > > the near future. > > > done, Patches 1-5 applied to the togreg branch of iio.git and pushed out > as testing for 0-day to see if it can find anything we missed. > > I've marked the fixes for stable, but am taking these the slow way > (via next merge window) so as to keep things simple for applying the > rest of the series later this cycle. > > I got a bit lost in the discussion but seems there are some minor > requests for changes so I guess I'll see a v13 of patches 6-12. 6-16 that is! > > Thanks, > > Jonathan > >
Hi Jonathan, On Sun, Jan 30, 2022 at 02:39:33PM +0000, Jonathan Cameron wrote: > On Sun, 9 Jan 2022 15:10:36 +0200 > Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > > > On Sat, Jan 8, 2022 at 10:53 PM Liam Beguin <liambeguin@gmail.com> wrote: > > > > > > Jonathan, Peter, Andy, > > > > > > I left out IIO_VAL_INT overflows for now, so that I can focus on getting > > > the rest of these changes pulled in, but I don't mind adding a patch for > > > that later on. > > > > > > This series focuses on adding temperature rescaling support to the IIO > > > Analog Front End (AFE) driver. > > > > > > The first few patches address minor bugs in IIO inkernel functions, and > > > prepare the AFE driver for the additional features. > > > > > > The main changes to the AFE driver include an initial Kunit test suite, > > > support for IIO_VAL_INT_PLUS_{NANO,MICRO} scales, and support for RTDs > > > and temperature transducer sensors. > > > > > > My apologies Andy for misunderstanding your left-shift comments, I don't > > > know where my head was at... Thanks for your patience! > > > > For the patches 1-5 > > Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> > > > > Jonathan, perhaps you may apply them, so Liam will have less burden in > > the near future. > > > done, Patches 1-5 applied to the togreg branch of iio.git and pushed out > as testing for 0-day to see if it can find anything we missed. > > I've marked the fixes for stable, but am taking these the slow way > (via next merge window) so as to keep things simple for applying the > rest of the series later this cycle. Thanks for taking these in. > I got a bit lost in the discussion but seems there are some minor > requests for changes so I guess I'll see a v13 of patches 6-12. I'm rebasing what's left on top of your to-greg branch, and will send out v13 today. Cheers, Liam > Thanks, > > Jonathan > >
Jonathan, Peter, Andy, I left out IIO_VAL_INT overflows for now, so that I can focus on getting the rest of these changes pulled in, but I don't mind adding a patch for that later on. This series focuses on adding temperature rescaling support to the IIO Analog Front End (AFE) driver. The first few patches address minor bugs in IIO inkernel functions, and prepare the AFE driver for the additional features. The main changes to the AFE driver include an initial Kunit test suite, support for IIO_VAL_INT_PLUS_{NANO,MICRO} scales, and support for RTDs and temperature transducer sensors. My apologies Andy for misunderstanding your left-shift comments, I don't know where my head was at... Thanks for your patience! Thanks you all again for your time, and Happy New Year! Liam Changes since v11: - update commits with my personal email since all this work was done on my own time - apply Peter's Reviewed-by to my local tree - fix use of units.h - make use of units.h more consistently in iio-rescale.c and in the tests - fix #include ordering - treat 04/16 as a fix. Move it, and add a Fixes: tag - fix undefined behavior on left-shift operation - add comment about fract_mult with iio_str_to_fixpoint() - reword commit message for 14/16, based on Andy's comments Changes since v10: - apply Andy's suggestion for offset calculations - make use of units.h more consistently Changes since v9: - make use of linux/units.h - reorder commits, fix fract_log2 before merging fract - keep fractional representation when not overflowing Changes since v8: - reword comment - fix erroneous 64-bit division - optimize and use 32-bit divisions when values are know to not overflow - keep IIO_VAL_FRACTIONAL scale when possible, if not default to fixed point - add test cases - use nano precision in test cases - simplify offset calculation in rtd_props() Changes since v7: - drop gcd() logic in rescale_process_scale() - use div_s64() instead of do_div() for signed 64-bit divisions - combine IIO_VAL_FRACTIONAL and IIO_VAL_FRACTIONAL_LOG2 scale cases - switch to INT_PLUS_NANO when accuracy is lost with FRACTIONAL scales - rework test logic to allow for small relative error - rename test variables to align error output messages Changes since v6: - rework IIO_VAL_INT_PLUS_{NANO,MICRO} based on Peter's suggestion - combine IIO_VAL_INT_PLUS_{NANO,MICRO} cases - add test cases for negative IIO_VAL_INT_PLUS_{NANO,MICRO} corner cases - force use of positive integers with gcd() - reduce risk of integer overflow in IIO_VAL_FRACTIONAL_LOG2 - fix duplicate symbol build error - apply Reviewed-by Changes since v5: - add include/linux/iio/afe/rescale.h - expose functions use to process scale and offset - add basic iio-rescale kunit test cases - fix integer overflow case - improve precision for IIO_VAL_FRACTIONAL_LOG2 Changes since v4: - only use gcd() when necessary in overflow mitigation - fix INT_PLUS_{MICRO,NANO} support - apply Reviewed-by - fix temperature-transducer bindings Changes since v3: - drop unnecessary fallthrough statements - drop redundant local variables in some calculations - fix s64 divisions on 32bit platforms by using do_div - add comment describing iio-rescaler offset calculation - drop unnecessary MAINTAINERS entry Changes since v2: - don't break implicit offset truncations - make a best effort to get a valid value for fractional types - drop return value change in iio_convert_raw_to_processed_unlocked() - don't rely on processed value for offset calculation - add INT_PLUS_{MICRO,NANO} support in iio-rescale - revert generic implementation in favor of temperature-sense-rtd and temperature-transducer - add separate section to MAINTAINERS file Changes since v1: - rebase on latest iio `testing` branch - also apply consumer scale on integer channel scale types - don't break implicit truncation in processed channel offset calculation - drop temperature AFE flavors in favor of a simpler generic implementation Liam Beguin (16): iio: inkern: apply consumer scale on IIO_VAL_INT cases iio: inkern: apply consumer scale when no channel scale is available iio: inkern: make a best effort on offset calculation iio: afe: rescale: use s64 for temporary scale calculations iio: afe: rescale: reorder includes iio: afe: rescale: expose scale processing function iio: afe: rescale: add INT_PLUS_{MICRO,NANO} support iio: afe: rescale: add offset support iio: afe: rescale: fix accuracy for small fractional scales iio: afe: rescale: reduce risk of integer overflow iio: afe: rescale: make use of units.h iio: test: add basic tests for the iio-rescale driver iio: afe: rescale: add RTD temperature sensor support iio: afe: rescale: add temperature transducers dt-bindings: iio: afe: add bindings for temperature-sense-rtd dt-bindings: iio: afe: add bindings for temperature transducers .../iio/afe/temperature-sense-rtd.yaml | 101 +++ .../iio/afe/temperature-transducer.yaml | 114 +++ drivers/iio/afe/iio-rescale.c | 296 +++++++- drivers/iio/inkern.c | 40 +- drivers/iio/test/Kconfig | 10 + drivers/iio/test/Makefile | 1 + drivers/iio/test/iio-test-rescale.c | 711 ++++++++++++++++++ include/linux/iio/afe/rescale.h | 36 + 8 files changed, 1259 insertions(+), 50 deletions(-) create mode 100644 Documentation/devicetree/bindings/iio/afe/temperature-sense-rtd.yaml create mode 100644 Documentation/devicetree/bindings/iio/afe/temperature-transducer.yaml create mode 100644 drivers/iio/test/iio-test-rescale.c create mode 100644 include/linux/iio/afe/rescale.h Range-diff against v11: 1: ae3cc93baee6 ! 1: a8ca9300ef2a iio: inkern: apply consumer scale on IIO_VAL_INT cases @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: inkern: apply consumer scale on IIO_VAL_INT cases @@ Commit message Make sure to always apply the scaling factor requested by the consumer. Fixes: 48e44ce0f881 ("iio:inkern: Add function to read the processed value") - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/inkern.c ## @@ drivers/iio/inkern.c: static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan, 2: 06f66e7f7403 ! 2: efaeceac8d87 iio: inkern: apply consumer scale when no channel scale is available @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: inkern: apply consumer scale when no channel scale is available @@ Commit message Make sure to always apply the scaling factor requested by the consumer. Fixes: adc8ec5ff183 ("iio: inkern: pass through raw values if no scaling") - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/inkern.c ## @@ drivers/iio/inkern.c: static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan, 3: 1717b82460c0 ! 3: 8131208a4454 iio: inkern: make a best effort on offset calculation @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: inkern: make a best effort on offset calculation @@ Commit message cases without breaking implicit truncations. Fixes: 48e44ce0f881 ("iio:inkern: Add function to read the processed value") - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/inkern.c ## @@ drivers/iio/inkern.c: EXPORT_SYMBOL_GPL(iio_read_channel_average_raw); -: ------------ > 4: 06202d8f6481 iio: afe: rescale: use s64 for temporary scale calculations -: ------------ > 5: 87b9d77f0d30 iio: afe: rescale: reorder includes 4: 6fc26588f651 ! 6: e9bf09ca9703 iio: afe: rescale: expose scale processing function @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: afe: rescale: expose scale processing function @@ Commit message In preparation for the addition of kunit tests, expose the logic responsible for combining channel scales. - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/afe/iio-rescale.c ## @@ - #include <linux/gcd.h> - #include <linux/iio/consumer.h> - #include <linux/iio/iio.h> -+#include <linux/iio/afe/rescale.h> - #include <linux/module.h> - #include <linux/of.h> - #include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/property.h> ++#include <linux/iio/afe/rescale.h> + #include <linux/iio/consumer.h> + #include <linux/iio/iio.h> + -struct rescale; - -struct rescale_cfg { @@ drivers/iio/afe/iio-rescale.c +int rescale_process_scale(struct rescale *rescale, int scale_type, + int *val, int *val2) +{ -+ unsigned long long tmp; ++ s64 tmp; -struct rescale { - const struct rescale_cfg *cfg; @@ drivers/iio/afe/iio-rescale.c + *val2 = rescale->denominator; + return IIO_VAL_FRACTIONAL; + case IIO_VAL_FRACTIONAL_LOG2: -+ tmp = *val * 1000000000LL; -+ do_div(tmp, rescale->denominator); ++ tmp = (s64)*val * 1000000000LL; ++ tmp = div_s64(tmp, rescale->denominator); + tmp *= rescale->numerator; -+ do_div(tmp, 1000000000LL); ++ tmp = div_s64(tmp, 1000000000LL); + *val = tmp; + return scale_type; + default: @@ drivers/iio/afe/iio-rescale.c int *val, int *val2, long mask) { struct rescale *rescale = iio_priv(indio_dev); -- unsigned long long tmp; +- s64 tmp; int ret; switch (mask) { @@ drivers/iio/afe/iio-rescale.c: static int rescale_read_raw(struct iio_dev *indio - *val2 = rescale->denominator; - return IIO_VAL_FRACTIONAL; - case IIO_VAL_FRACTIONAL_LOG2: -- tmp = *val * 1000000000LL; -- do_div(tmp, rescale->denominator); +- tmp = (s64)*val * 1000000000LL; +- tmp = div_s64(tmp, rescale->denominator); - tmp *= rescale->numerator; -- do_div(tmp, 1000000000LL); +- tmp = div_s64(tmp, 1000000000LL); - *val = tmp; - return ret; - default: @@ include/linux/iio/afe/rescale.h (new) +#ifndef __IIO_RESCALE_H__ +#define __IIO_RESCALE_H__ + ++#include <linux/types.h> +#include <linux/iio/iio.h> + ++struct device; +struct rescale; + +struct rescale_cfg { 5: 8e63c4036157 ! 7: 865296d2bc4f iio: afe: rescale: add INT_PLUS_{MICRO,NANO} support @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: afe: rescale: add INT_PLUS_{MICRO,NANO} support @@ Commit message Some ADCs use IIO_VAL_INT_PLUS_{NANO,MICRO} scale types. Add support for these to allow using the iio-rescaler with them. - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/afe/iio-rescale.c ## @@ @@ drivers/iio/afe/iio-rescale.c #include <linux/property.h> +#include <linux/units.h> - int rescale_process_scale(struct rescale *rescale, int scale_type, + #include <linux/iio/afe/rescale.h> + #include <linux/iio/consumer.h> +@@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale, int scale_type, int *val, int *val2) { - unsigned long long tmp; + s64 tmp; + s32 rem; + u32 mult; + u32 neg; @@ drivers/iio/afe/iio-rescale.c case IIO_VAL_FRACTIONAL: @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale, int scale_type, tmp *= rescale->numerator; - do_div(tmp, 1000000000LL); + tmp = div_s64(tmp, 1000000000LL); *val = tmp; + return scale_type; + case IIO_VAL_INT_PLUS_NANO: + case IIO_VAL_INT_PLUS_MICRO: -+ mult = scale_type == IIO_VAL_INT_PLUS_NANO ? NANO : MICRO; ++ mult = scale_type == IIO_VAL_INT_PLUS_NANO ? GIGA : MEGA; + + /* + * For IIO_VAL_INT_PLUS_{MICRO,NANO} scale types if either *val 6: eea57faec241 ! 8: aea3159ed169 iio: afe: rescale: add offset support @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: afe: rescale: add offset support @@ Commit message This is a preparatory change required for the addition of temperature sensing front ends. - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/afe/iio-rescale.c ## @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale, int scale_type, @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale + *val = div_s64(tmp, scale) + schan_off; + return IIO_VAL_INT; + case IIO_VAL_INT_PLUS_NANO: -+ tmp = (s64)rescale->offset * NANO; -+ tmp2 = ((s64)scale * NANO) + scale2; ++ tmp = (s64)rescale->offset * GIGA; ++ tmp2 = ((s64)scale * GIGA) + scale2; + *val = div64_s64(tmp, tmp2) + schan_off; + return IIO_VAL_INT; + case IIO_VAL_INT_PLUS_MICRO: -+ tmp = (s64)rescale->offset * MICRO; -+ tmp2 = ((s64)scale * MICRO) + scale2; ++ tmp = (s64)rescale->offset * MEGA; ++ tmp2 = ((s64)scale * MEGA) + scale2; + *val = div64_s64(tmp, tmp2) + schan_off; + return IIO_VAL_INT; + default: 7: 6bc5dd8c92ac < -: ------------ iio: afe: rescale: use s64 for temporary scale calculations 8: 7d426d67a7fd ! 9: 7b518cba1cb5 iio: afe: rescale: fix accuracy for small fractional scales @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: afe: rescale: fix accuracy for small fractional scales @@ Commit message integer part. Switch to an IIO_VAL_INT_PLUS_NANO scale type in such cases to maintain accuracy. - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/afe/iio-rescale.c ## @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale, int scale_type, @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale + return IIO_VAL_INT_PLUS_NANO; case IIO_VAL_INT_PLUS_NANO: case IIO_VAL_INT_PLUS_MICRO: - mult = scale_type == IIO_VAL_INT_PLUS_NANO ? NANO : MICRO; + mult = scale_type == IIO_VAL_INT_PLUS_NANO ? GIGA : MEGA; 9: dbea6ae8fec2 ! 10: 4310bb2153e2 iio: afe: rescale: reduce risk of integer overflow @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: afe: rescale: reduce risk of integer overflow @@ Commit message a 64-bit integer. Since the rescaling is only performed on *val, reuse the IIO_VAL_FRACTIONAL_LOG2 case. - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/afe/iio-rescale.c ## @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale, int scale_type, @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale + if (scale_type == IIO_VAL_FRACTIONAL) + tmp = *val2; + else -+ tmp = 1 << *val2; ++ tmp = ULL(1) << *val2; rem2 = *val % (int)tmp; *val = *val / (int)tmp; 10: 9ab1138449d3 ! 11: fd794683186a iio: afe: rescale: make use of units.h @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: afe: rescale: make use of units.h Make use of well-defined SI metric prefixes to improve code readability. - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> ## drivers/iio/afe/iio-rescale.c ## @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale, int scale_type, @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale fallthrough; case IIO_VAL_FRACTIONAL_LOG2: - tmp = (s64)*val * 1000000000LL; -+ tmp = (s64)*val * NANO; ++ tmp = (s64)*val * GIGA; tmp = div_s64(tmp, rescale->denominator); tmp *= rescale->numerator; - tmp = div_s64_rem(tmp, 1000000000LL, &rem); -+ tmp = div_s64_rem(tmp, NANO, &rem); ++ tmp = div_s64_rem(tmp, GIGA, &rem); *val = tmp; if (!rem) @@ drivers/iio/afe/iio-rescale.c: int rescale_process_scale(struct rescale *rescale *val2 = rem / (int)tmp; if (rem2) - *val2 += div_s64((s64)rem2 * 1000000000LL, tmp); -+ *val2 += div_s64((s64)rem2 * NANO, tmp); ++ *val2 += div_s64((s64)rem2 * GIGA, tmp); return IIO_VAL_INT_PLUS_NANO; case IIO_VAL_INT_PLUS_NANO: @@ drivers/iio/afe/iio-rescale.c: static int rescale_current_sense_amplifier_props( */ - factor = gcd(sense, 1000000); - rescale->numerator = 1000000 / factor; -+ factor = gcd(sense, MICRO); -+ rescale->numerator = MICRO / factor; ++ factor = gcd(sense, MEGA); ++ rescale->numerator = MEGA / factor; rescale->denominator = sense / factor; factor = gcd(rescale->numerator, gain_mult); @@ drivers/iio/afe/iio-rescale.c: static int rescale_current_sense_shunt_props(stru - factor = gcd(shunt, 1000000); - rescale->numerator = 1000000 / factor; -+ factor = gcd(shunt, MICRO); -+ rescale->numerator = MICRO / factor; ++ factor = gcd(shunt, MEGA); ++ rescale->numerator = MEGA / factor; rescale->denominator = shunt / factor; return 0; 11: 3006151cd193 ! 12: 5053bcff8445 iio: test: add basic tests for the iio-rescale driver @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: test: add basic tests for the iio-rescale driver @@ Commit message Then run: $ ./tools/testing/kunit/kunit.py run --kunitconfig .kunitconfig - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/test/Kconfig ## @@ @@ drivers/iio/test/iio-test-rescale.c (new) + * Copyright (c) 2021 Liam Beguin <liambeguin@gmail.com> + */ + -+#include <kunit/test.h> +#include <linux/gcd.h> ++#include <linux/overflow.h> ++#include <linux/units.h> ++ +#include <linux/iio/afe/rescale.h> +#include <linux/iio/iio.h> -+#include <linux/overflow.h> ++ ++#include <kunit/test.h> + +struct rescale_tc_data { + const char *name; @@ drivers/iio/test/iio-test-rescale.c (new) + */ +static int iio_str_to_nano(const char *str, s64 *nano) +{ -+ int fract_mult = 100000000LL; + int tmp, tmp2; + int ret = 0; + -+ ret = iio_str_to_fixpoint(str, fract_mult, &tmp, &tmp2); ++ /* ++ * iio_str_to_fixpoint() uses 10^8 here instead of 10^9 as fract_mult is ++ * the multiplier for the first decimal place. ++ */ ++ ret = iio_str_to_fixpoint(str, 100000000, &tmp, &tmp2); + if (ret < 0) + return ret; + + if (tmp < 0) + tmp2 *= -1; + -+ *nano = (s64)tmp * 10 * fract_mult + tmp2; ++ *nano = (s64)tmp * GIGA + tmp2; + + return ret; +} @@ drivers/iio/test/iio-test-rescale.c (new) + return -EINVAL; + } + -+ err = 1000000 * abs(exp - real); -+ err = div64_u64(err, abs(exp)); -+ return (int)err; ++ err = MEGA * abs(exp - real); ++ ++ return (int)div64_u64(err, abs(exp)); +} + +static void iio_rescale_test_scale(struct kunit *test) 12: d4229e8d7f24 ! 13: aec4f7e44277 iio: afe: rescale: add RTD temperature sensor support @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: afe: rescale: add RTD temperature sensor support @@ Commit message give range (usually 0 to 100 degrees Celsius). Common types of RTDs include PT100, PT500, and PT1000. - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/afe/iio-rescale.c ## @@ drivers/iio/afe/iio-rescale.c: static int rescale_voltage_divider_props(struct device *dev, @@ drivers/iio/afe/iio-rescale.c: static int rescale_voltage_divider_props(struct d + return ret; + } + -+ tmp = r0 * iexc * alpha / MICRO; -+ factor = gcd(tmp, MICRO); -+ rescale->numerator = MICRO / factor; ++ tmp = r0 * iexc * alpha / MEGA; ++ factor = gcd(tmp, MEGA); ++ rescale->numerator = MEGA / factor; + rescale->denominator = tmp / factor; + -+ rescale->offset = -1 * ((r0 * iexc) / MICRO * MILLI); ++ rescale->offset = -1 * ((r0 * iexc) / MEGA * MILLI); + + return 0; +} 13: b93e303c5e60 ! 14: e5467185f3b3 iio: afe: rescale: add temperature transducers @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## iio: afe: rescale: add temperature transducers A temperature transducer is a device that converts a thermal quantity - into any other physical quantity. This patch add support for temperature - to voltage (like the LTC2997) and temperature to current (like the - AD590) linear transducers. + into any other physical quantity. This patch adds support for + temperature to voltage (like the LTC2997) and temperature to current + (like the AD590) linear transducers. In both cases these are assumed to be connected to a voltage ADC. - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> + Reviewed-by: Peter Rosin <peda@axentia.se> ## drivers/iio/afe/iio-rescale.c ## @@ drivers/iio/afe/iio-rescale.c: static int rescale_temp_sense_rtd_props(struct device *dev, @@ drivers/iio/afe/iio-rescale.c: static int rescale_temp_sense_rtd_props(struct de + return ret; + } + -+ rescale->numerator = MICRO; ++ rescale->numerator = MEGA; + rescale->denominator = alpha * sense; + + rescale->offset = div_s64((s64)offset * rescale->denominator, 14: 7bdd57435c5c ! 15: 3d16dc359e35 dt-bindings: iio: afe: add bindings for temperature-sense-rtd @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## dt-bindings: iio: afe: add bindings for temperature-sense-rtd @@ Commit message binding describe one case, the measurement of a temperature through the voltage across an RTD resistor such as a PT1000. - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> Reviewed-by: Rob Herring <robh@kernel.org> + Reviewed-by: Peter Rosin <peda@axentia.se> ## Documentation/devicetree/bindings/iio/afe/temperature-sense-rtd.yaml (new) ## @@ 15: 604ef3e42c07 ! 16: b70fb25c3643 dt-bindings: iio: afe: add bindings for temperature transducers @@ ## Metadata ## -Author: Liam Beguin <lvb@xiphos.com> +Author: Liam Beguin <liambeguin@gmail.com> ## Commit message ## dt-bindings: iio: afe: add bindings for temperature transducers @@ Commit message This binding describe one case, the measurement of a temperature through a temperature transducer (either voltage or current). - Signed-off-by: Liam Beguin <lvb@xiphos.com> + Signed-off-by: Liam Beguin <liambeguin@gmail.com> Reviewed-by: Rob Herring <robh@kernel.org> + Reviewed-by: Peter Rosin <peda@axentia.se> ## Documentation/devicetree/bindings/iio/afe/temperature-transducer.yaml (new) ## @@ base-commit: 2b6bff0b122785f09cfbdc34b1aa9edceea6e4c1