mfd: wolfson: Convert to use maple tree register cache

The maple tree register cache is based on a much more modern data structure
than the rbtree cache and makes optimisation choices which are probably
more appropriate for modern systems than those made by the rbtree cache.

Signed-off-by: Bo Liu <liubo03@inspur.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20240206071314.8721-11-liubo03@inspur.com
Signed-off-by: Lee Jones <lee@kernel.org>

ALSA: ac97: make remove callback of ac97 driver void returned

Since commit fc7a6209d571 ("bus: Make remove callback return void")
forces bus_type::remove be void-returned, it doesn't make much sense
for any bus based driver implementing remove callbalk to return
non-void to its caller.

As such, change the remove function for ac97 based drivers to return
void.

Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Link: https://lore.kernel.org/r/TYCP286MB2323A5AB1B2578EF4FA15DA7CAFB9@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Takashi Iwai <tiwai@suse.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mfd: wm97xx-core: Platform data can be NULL

It is not mandatory that platform data is passed along the ac97
codec. Actually there are configuration without a battery connected to
the ADC of the codec.

This is for example the case for the PXA zylonite platform, so fix the
NULL dereferencing by adding a test.

Fixes: a5c6951c49fb ("mfd: wm97xx-core: core support for wm97xx Codec")
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: wm97xx-core: core support for wm97xx Codec

The WM9705, WM9712 and WM9713 are highly integrated codecs, with an
audio codec, DAC and ADC, GPIO unit and a touchscreen interface.

Historically the support was spread across drivers/input/touchscreen and
sound/soc/codecs. The sharing was done through ac97 bus sharing. This
model will not withstand the new AC97 bus model, where codecs are
discovered on runtime.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>