Re: [PATCH 0/3] IIO: st_sensors_i2c: improve device enumeration

[Andy Shevchenko]

On Fri, Jun 29, 2018 at 1:30 PM, Nikolaus Voss
<nikolaus.voss@xxxxxxxxxxxxxxxxxxxxx> wrote:
> When trying to instantiate a st_accel_i2c device from an ACPI based
> system, I ran into some problems:
>
> For my device, there is no ACPI match table entry, so rather than
> creating /allocating a new ACPI HID for the device, I wanted to use an
> existing DT table compatible entry via creating an ACPI_DT_NAMESPACE_HID
> /PRP0001 HID ACPI entry (see Documentation/acpi/enumeration.txt).
>
> This did not work because st_accel_i2c.c bails out if there is a ACPI
> node but no ACPI table match instead of looking for a match from one of
> the fallback mechanisms (patch 1).
>
> Patch 2 removes an error message when a ACPI node exists but no table
> entry is found (this doesn't need to be fatal because of the fallback).
>
> Patch 3 syncs the strings in the I2C device table (which is used by the
> I2C core for fallback matching) with the DT compatible strings, so a
> PRP0001 entry can use the same compatible strings as a corresponding
> DT entry. As far as I can see, the old I2C table strings aren't used
> in mainline, so renaming them should be safe.
>

I'm not sure I understand how ->probe_new() is supposed to work
against i2c_id_table, but I don't care for legacy platform data
anyway.

What I would like to point to is device_get_match_data() API which
should simplify / unify the case how you get driver data.

> Nikolaus Voss (3):
>   IIO: st_accel_i2c.c: Use fallback if DT/ACPI enum failed
>   IIO: st_sensors_i2c.c: Don't print error on failed ACPI match
>   IIO: st_accel.h: sync DT and I2C device ID table strings
>
>  drivers/iio/accel/st_accel.h                  | 32 +++++++++----------
>  drivers/iio/accel/st_accel_i2c.c              | 21 ++++++------
>  .../iio/common/st_sensors/st_sensors_i2c.c    |  5 ++-
>  3 files changed, 30 insertions(+), 28 deletions(-)
>
> --
> 2.17.1
>



-- 
With Best Regards,
Andy Shevchenko