On Sun, 27 Feb 2022 12:49:53 +0000
Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
> On Fri, 25 Feb 2022 14:01:26 +0100
> Nuno Sá <nuno.sa@xxxxxxxxxx> wrote:
>
> Hi Nuno,
>
> Given we are close to the end of this cycle and Andy has been heavily involved
> in review of this one so I want to give more time for Andy to potentially take
> another look..
>
> Hence, I'm going to do something unusual and push out an extra-testing branch with this
> on so we can get through the autobuilder tests in parallel with that extra time.
>
> So, applied to the new extra-testing branch of iio.git with the intent to apply
> it to togreg later in a day or two subject to any last minute feedback.
Given we may be very near to the cut off for the merge window (I aim to do a pull
request after linux-next is out tomorrow), I've applied this to the togreg
branch of iio.git and pushed it out to be picked up for linux-next.
Thanks,
Jonathan
>
> Thanks,
>
> Jonathan
>
>
> > The ABI defined for this driver has some subtleties that were previously
> > discussed in this RFC [1]. This might not be the final state but,
> > hopefully, we are close to it:
> >
> > toggle mode channels:
> >
> > * out_voltageY_toggle_en
> > * out_voltageY_raw0
> > * out_voltageY_raw1
> > * out_voltageY_symbol
> >
> > dither mode channels:
> >
> > * out_voltageY_dither_en
> > * out_voltageY_dither_raw
> > * out_voltageY_dither_raw_available
> > * out_voltageY_dither_offset
> > * out_voltageY_dither_frequency
> > * out_voltageY_dither_frequency_available
> > * out_voltageY_dither_phase
> > * out_voltageY_dither_phase_available
> >
> > Default channels won't have any of the above ABIs. A channel is toggle
> > capable if the devicetree 'adi,toggle-mode' flag is set. For dither, the
> > assumption is more silent. If 'adi,toggle-mode' is not given and a
> > channel is associated with a TGPx pin through 'adi,toggle-dither-input',
> > then the channel is assumed to be dither capable (there's no point in
> > having a dither capable channel without an input clock).
> >
> > changes in v2:
> >
> > ltc2688:
> > * Use local buffer for regmap read. Do not assume that reg is part of
> > larger buffer;
> > * Renamed GPIO to "clr" so that is consistent with the datasheet;
> > * Renamed 'mask' and 'm' to info. 'mask' is a thing from the past;
> > * Removed 'LTC2688_CHAN_TOGGLE()' and defined to static ext_info arrays;
> > * Use 'regmap_set_bits' to set external ref;
> > * Use FIELD_{PREP|GET} for dither amplitude and channel calibbias where
> > only 13bits are used;
> > * Use 'regmap_write()' instead of update_bits for channels settings;
> > * Init 'val' at the beginning of the channel configuration loop
> > (and drop mask);
> > * Comment 'ltc2688_reg_writable()' to account for the special condition;
> > * Kmemdup default channels so that it can be safely changed per probed
> > device;
> > * Replace extended info multiplexer functions by individual functions;
> > * Use raw0 ABI for toggle channels;
> > * Use dedicated offset ABI for dither channels;
> > * Misc changes (spell fixes, blank lines...);
> > * Have a clock property per channel. Note that we this I moved to OF
> > since we now have to use 'devm_get_clk_from_child()' which is using
> > device_node. Note that I could use 'to_of_node()' but mixing of.h and
> > property.h does not feel like a good idea.
> >
> > ABI:
> > * Added out_voltageY_raw0 ABI for toggle mode;
> > * Added out_voltageY_dither_offset.
> >
> > Bindings:
> > * Use standard microvolt unit;
> > * Added constrains for adi,output-range-microvolt and removed negative
> > values from the dts example;
> > * Moved clocks to the channel object;
> > * Dropped clock-names;
> > * Add a dependency between 'adi,toggle-dither-input' and 'clocks'.
> >
> > Changes in v3:
> >
> > ltc2688:
> > * Fix mismatch between functions and function pointers detected by kernel
> > test bot;
> > * Always use if (ret) when ret > 0 has no meaning;
> > * Rename ltc2688_bulk_disable -> ltc2688_disable_regulators;
> > * Report dither phase in radians rather than degrees.
> >
> > ABI:
> > * Specify units for dither_phase and dither_freqency;
> > * Say why its useful to have dither_en and toggle_en;
> > * Combine out_voltageY_raw0 and out_voltageY_raw1;
> > * Fix some description issues in out_voltageY_raw{0|1} and
> > out_voltageY_symbol.
> >
> > Bindings:
> > * Remove mentions to ABI (linux specifix);
> > * Slightly rephrased VREF and adi,toggle-dither-input properties and
> > suggested.
> >
> > changes in v4:
> >
> > ltc2688:
> > * Use reg_size + val_size instead of plain 3 in regmap;
> > * Use out_unlock instead of unlock in goto labels;
> > * Add comma to LTC2688_CHANNEL(), ltc2688_regmap_bus and
> > ltc2688_regmap_bus;
> > * Use __clear_bit() instead of clear_bit();
> > * Flip the logic in vref regulator so that error condition is handled
> > first;
> > * Change to device API. With this, we need to_of_node()
> > for devm_get_clk_from_child().
> >
> > ABI:
> > * Update kernel version.
> >
> > Bindings:
> > * Add Rob's Rb tag.
> >
> > [1]: https://marc.info/?l=linux-iio&m=163662843603265&w=2
> >
> > Nuno Sá (3):
> > iio: dac: add support for ltc2688
> > iio: ABI: add ABI file for the LTC2688 DAC
> > dt-bindings: iio: Add ltc2688 documentation
> >
> > .../ABI/testing/sysfs-bus-iio-dac-ltc2688 | 86 ++
> > .../bindings/iio/dac/adi,ltc2688.yaml | 146 +++
> > MAINTAINERS | 9 +
> > drivers/iio/dac/Kconfig | 11 +
> > drivers/iio/dac/Makefile | 1 +
> > drivers/iio/dac/ltc2688.c | 1071 +++++++++++++++++
> > 6 files changed, 1324 insertions(+)
> > create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-dac-ltc2688
> > create mode 100644 Documentation/devicetree/bindings/iio/dac/adi,ltc2688.yaml
> > create mode 100644 drivers/iio/dac/ltc2688.c
> >
>
