On Sun, 7 Feb 2021 15:45:59 +0000 Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > > This is an 'old' driver in IIO that has been in staging a while. > First submitted in October 2010. > > I wanted to try and experiment and picked this driver to try it with. > > The cleanup etc here was all tested against some basic emulation > added to QEMU rather than real hardware. Once I've cleaned that up > a tiny bit I'll push it up to https://github.com/jic23/qemu Now up at: https://github.com/jic23/qemu/tree/iio-ad7150 The device emulation is rather messy. As arm / virt builds the DT tree alongside the instantiation of devices it was a very convenient place to hack an i2c bus and the ad7150 in using the existing pl061 to provide suitable interrupt lines. Note that I don't care about VM migration or anything like that so the implementation is rather more minimal than would be needed for normal QEMU device emulation. Anyhow, gives an idea of what is needed for anyone who is curious. qom-list /machine/unattached/device[9] lists the various things that can be controlled including. ch2_capacitance (int) ch1_capacitance_avg (int) ch2_event_state (int) ch1_event_state (int) ch2_capacitance_avg (int) ch1_capacitance (int) Event state is a bit simplistic in that you have direct control of the gpio lines. I could have implemented a state machine so that the actual thresholds etc were used, but the adaptive mode is sufficiently complex that I haven't yet done so. Jonathan > Note that for now I'm not proposing to upstream this to QEMU but > would be interested in hearing if people thing it is a good idea to > do so. > > Whilst it's obviously hard to be absolutely sure that the emulation is > correct, the fact that the original driver worked as expected and the > cleaned up version still does is certainly encouraging. > > Note however, that there were a few more significant changes in here than > basic cleanup. > 1. Interrupts / events were handled in a rather esoteric fashion. > (Always on, window modes represented as magnitudes). > Note that for two channel devices there are separate lines. The original > driver was not supporting this at all. > They now look more like a standard IIO driver and reflect experience > that we've gained over the years in dealing with devices where these > aren't interrupt lines as such, but rather reporters of current status. > 2. Timeouts were handled in a fashion that clearly wouldn't work. > > Note that this moving out of staging makes a few bits of ABI 'official' > and so those are added to the main IIO ABI Docs. > > Thanks in advance to anyone who has time to take a look. > > Jonathan > > > Jonathan Cameron (24): > staging:iio:cdc:ad7150: use swapped reads for i2c rather than open > coding. > staging:iio:cdc:ad7150: Remove magnitude adaptive events > staging:iio:cdc:ad7150: Refactor event parameter update > staging:iio:cdc:ad7150: Timeout register covers both directions so > both need updating > staging:iio:cdc:ad7150: Drop platform data support > staging:iio:cdc:ad7150: Handle variation in chan_spec across device > and irq present or not > staging:iio:cdc:ad7150: Simplify event handling by only using rising > direction. > staging:iio:cdc:ad7150: Drop noisy print in probe > staging:iio:cdc:ad7150: Add sampling_frequency support > iio:event: Add timeout event info type > staging:iio:cdc:ad7150: Change timeout units to seconds and use core > support > staging:iio:cdc:ad7150: Rework interrupt handling. > staging:iio:cdc:ad7150: More consistent register and field naming > staging:iio:cdc:ad7150: Reorganize headers. > staging:iio:cdc:ad7150: Tidy up local variable positioning. > staging:iio:cdc:ad7150: Drop unnecessary block comments. > staging:iio:cdc:ad7150: Shift the _raw readings by 4 bits. > staging:iio:cdc:ad7150: Add scale and offset to > info_mask_shared_by_type > staging:iio:cdc:ad7150: Really basic regulator support. > staging:iio:cdc:ad7150: Add of_match_table > dt-bindings:iio:cdc:adi,ad7150 binding doc > iio:Documentation:ABI Add missing elements as used by the adi,ad7150 > staging:iio:cdc:ad7150: Add copyright notice given substantial > changes. > iio:cdc:ad7150: Move driver out of staging. > > Documentation/ABI/testing/sysfs-bus-iio | 33 + > .../bindings/iio/cdc/adi,ad7150.yaml | 69 ++ > drivers/iio/Kconfig | 1 + > drivers/iio/Makefile | 1 + > drivers/iio/cdc/Kconfig | 17 + > drivers/iio/cdc/Makefile | 6 + > drivers/iio/cdc/ad7150.c | 678 ++++++++++++++++++ > drivers/iio/industrialio-event.c | 1 + > drivers/staging/iio/cdc/Kconfig | 10 - > drivers/staging/iio/cdc/Makefile | 3 +- > drivers/staging/iio/cdc/ad7150.c | 655 ----------------- > include/linux/iio/types.h | 1 + > 12 files changed, 808 insertions(+), 667 deletions(-) > create mode 100644 Documentation/devicetree/bindings/iio/cdc/adi,ad7150.yaml > create mode 100644 drivers/iio/cdc/Kconfig > create mode 100644 drivers/iio/cdc/Makefile > create mode 100644 drivers/iio/cdc/ad7150.c > delete mode 100644 drivers/staging/iio/cdc/ad7150.c >
