Hi, On 11/5/20 11:38 AM, Andy Shevchenko wrote: > On Thu, Nov 5, 2020 at 10:00 AM Hans de Goede <hdegoede@xxxxxxxxxx> wrote: >> >> Hi All, >> >> As the subject says this series is mostly about passing the ACPI fwnode to >> i2c-clients instantiated by the i2c-multi-instantiate code. >> >> As discussed here: >> https://bugzilla.kernel.org/show_bug.cgi?id=198671 >> >> BOSC0200 ACPI devices may sometimes describe 2 accelerometers in a single >> ACPI device, while working on this I noticed that BOSC0200 ACPI nodes >> contain ACCEL_MOUNT_MATRIX info (unlike all the other ACPI ids for bmc150 >> accelerometers). Which is why I wanted to pass the fwnode so that we >> could use this info in the bmc150-accel driver. >> >> The plan was to use i2c-multi-instantiate for this, but doing so will >> change the modalias and /lib/udev/hwdb.d/60-sensor.hwdb matches on >> the modalias for various quirks setting ACCEL_MOUNT_MATRIX. So then the >> plan became to first add support for the mount-matrix provided inside >> the BOSC0200 ACPI node, making the udev info unnecessary. But for at >> least 1 model (and probably more) the BOSC0200 ACPI node and hwdb info >> does not match and since the hwdb info is added by users of the actual >> devices we can assume it is correct, so it seems that we cannot always >> trust the ACPI provided info. This is ok, the hwdb info overrides it >> (iio-sensor-proxy prefers the udev provided mount-matrix over the >> one provided by the driver) but this means that we MUST keep the >> existing hwdb matches working, which means that we cannot use >> i2c-multi-instantiate for this. >> >> Instead I will dust of an old patch for this from Jeremy Cline: >> https://patchwork.kernel.org/project/linux-iio/patch/010001602cf53153-39ad69f1-1b39-4e6d-a748-9455a16c2fbd-000000@xxxxxxxxxxxxxxxxxxx/ >> >> Which deals with there being 2 accelerometers inside the bmc150-accel >> driver. >> >> But before coming to the conclusion that i2c-multi-instantiate >> would not work I had already written this series. Since this might >> be useful for some other case in the future I'm sending this out >> as a RFC now, mostly so that it gets added to the archives. > > I think they are in pretty good shape (only the 4th required a bit of > attention). FWIW I agree with the changes which you suggest for the 4th patch. > Please, send as non-RFC and also Cc Heikki (just in case if he has > comments wrt INT3515). But do we really want to land these changes, while ATM we do not really have any need for them ? Esp. the "platform/x86: i2c-multi-instantiate: Pass ACPI fwnode to instantiated I2C-clients" Change is not without a chance of regressions. The acpi_device_is_first_physical_node() behavior surprised me a bit while working on the BOSC0200 changes. So I'm not 100% sure I have managed to see / think of all implications of this change. Heikki do you now (or in the near future) need access to the fwnode for the TypeC controllers handled by the i2c-multi-instantiate code ? Note that if we do decide to move forward with this set, it should probably be merged in its entirety by Wolfram as it also makes i2c-core changes (or Wolfram could just merge the i2c-core change and provide an immutable branch for me to merge into pdx86/for-next. And then your (Andy's) cleanup series can be applied on top of this once merged. Regards, Hans
