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H A Dbma150.cf069b5a0 Sat Apr 01 11:43:47 CDT 2017 H. Nikolaus Schaller <hns@goldelico.com> Input: bma150 - remove support for bma150

This essentially reverts commit baf28d91e7b1 ("Input: bma150 - avoid
binding to bma180 if IIO bma180 driver present") and commit ef3714fdbc8d
("Input: bma150 - extend chip detection for bma180")

Rationale: initially (2012) the GTA04 device using a bma180 chip simply
referenced the bma150 platform driver in its board file [1] which happened
to work in all scenarios that were tested.

When conversion to DT started (2014), we needed to make the driver be still
recognised. Hence we introduced the compatibility to the bma180 chip in
Linux 3.15-rc5 [2] without further checks if it is really 100% compatible.
This worked flawlessly for years with the GTA04 device.

Recently (2016), Hans de Goede pointed out that the chips are not as
similar as they appeared and the driver works with the bma180 for the GTA04
only by good luck. He proposed to remove the bma180 support completely [3],
but we still did need it until we have a replacement. Thus, a conditional
compile was added.

We have now developed a generic iio-input-bridge which works with any 2 or
3 axis iio based accelerometer. It has been tested on GTA04 and Pyra and
works as expected. Therefore we can remove the bma180 support from this
driver completely. User-space API compatibility can be restored by using
the iio-input-bridge.

Maybe it is time to convert the bma150 driver to iio as well and retire the
accelerometer input drivers completely but this is a different story and
task.

[1]: https://github.com/neilbrown/linux/blob/gta04/3.2.y/arch/arm/mach-omap2/board-omap3gta04.c#L976
[2]: https://patchwork.kernel.org/patch/3961171/
[3]: https://patchwork.kernel.org/patch/9325481/

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
f069b5a0 Sat Apr 01 11:43:47 CDT 2017 H. Nikolaus Schaller <hns@goldelico.com> Input: bma150 - remove support for bma150

This essentially reverts commit baf28d91e7b1 ("Input: bma150 - avoid
binding to bma180 if IIO bma180 driver present") and commit ef3714fdbc8d
("Input: bma150 - extend chip detection for bma180")

Rationale: initially (2012) the GTA04 device using a bma180 chip simply
referenced the bma150 platform driver in its board file [1] which happened
to work in all scenarios that were tested.

When conversion to DT started (2014), we needed to make the driver be still
recognised. Hence we introduced the compatibility to the bma180 chip in
Linux 3.15-rc5 [2] without further checks if it is really 100% compatible.
This worked flawlessly for years with the GTA04 device.

Recently (2016), Hans de Goede pointed out that the chips are not as
similar as they appeared and the driver works with the bma180 for the GTA04
only by good luck. He proposed to remove the bma180 support completely [3],
but we still did need it until we have a replacement. Thus, a conditional
compile was added.

We have now developed a generic iio-input-bridge which works with any 2 or
3 axis iio based accelerometer. It has been tested on GTA04 and Pyra and
works as expected. Therefore we can remove the bma180 support from this
driver completely. User-space API compatibility can be restored by using
the iio-input-bridge.

Maybe it is time to convert the bma150 driver to iio as well and retire the
accelerometer input drivers completely but this is a different story and
task.

[1]: https://github.com/neilbrown/linux/blob/gta04/3.2.y/arch/arm/mach-omap2/board-omap3gta04.c#L976
[2]: https://patchwork.kernel.org/patch/3961171/
[3]: https://patchwork.kernel.org/patch/9325481/

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>