Re: [PATCH 00/14] mfd: unused driver purge

On Wed, 9 Sep 2026 15:21:37 +0200, Arnd Bergmann [off-list ref] said:

From: Arnd Bergmann <arnd@arndb.de>

As part of my cleanup of old platforms, I had a look at all drivers that
may have become unused because the last platform_data or DT definition
was removed, or because of unmet Kconfig dependencies.

These are all the mfd drivers I found. The first ten in the list
actually turned out to have been unusable long before my series, and
I have added explanations on how I determined this in each patch. The
last four patches are still in use in linux-7.3 but become unused after
my series [1] that I hope to get merged for 7.4.

Somewhat unorthodox, I took a shortcut here and remove both the mfd drivers
and the corresponding subsystem drivers (gpio, hwmon, iio, input, led,
media, power, regulator, rtc, video, watchdog, asoc) in a combined patch,
to simplify the interdependencies: removing just the mfd driver would
leave unselectable or broken drivers in other subsystems.  I also have
additional patches for each of the other subsystems, currently a total
of 300 patches, many of which still need better testing or proper
changelog texts.

Please let me know if you all think this approach is ok, or if I should
explode this further and turn these 14 patches into 70 individual ones
by splitting them per subsystem.

See [2] for the current state of the overall series.

     Arnd

[1] https://lore.kernel.org/lkml/20260908152808.3928630-1-arnd@kernel.org/ (local)
[2] https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git/log/?h=board-remove-7.3

Arnd Bergmann (14):
  mfd: remove unused 88pm80x driver
  mfd: remove unused rdc321x southbridge support
  mfd: remove unused si476x driver
  mfd: remove unused wm8400 driver
  mfd: remove unused adp5520 driver
  mfd: remove unused da903x driver
  mfd: remove unused lp8788 driver
  mfd: remove unused aat2870 driver
  mfd: remove unused lm3533 driver
  mfd: remove unused rc5t583 driver
  mfd: remove unused wm8350 driver
  mfd: remove unused mcp-sa11x0/ucb1x00 driver
  mfd: remove unused menelaus driver
  mfd: remove unused iPaq micro driver

 .../ABI/testing/sysfs-class-backlight         |   11 -
 Documentation/admin-guide/devices.txt         |    1 -
 .../admin-guide/media/radio-cardlist.rst      |    1 -
 Documentation/admin-guide/media/si476x.rst    |  160 --
 .../admin-guide/media/v4l-drivers.rst         |    1 -
 .../devicetree/bindings/regulator/88pm800.txt |   38 -
 Documentation/hwmon/index.rst                 |    1 -
 Documentation/hwmon/wm8350.rst                |   30 -
 .../watchdog/watchdog-parameters.rst          |    7 -
 MAINTAINERS                                   |   14 -
 drivers/gpio/Kconfig                          |   22 -
 drivers/gpio/Makefile                         |    3 -
 drivers/gpio/gpio-adp5520.c                   |  169 --
 drivers/gpio/gpio-rdc321x.c                   |  199 --
 drivers/gpio/gpio-wm8350.c                    |  144 --

For GPIO:

Acked-by: Bartosz Golaszewski <redacted>