[PATCH v2 1/4] ASoC: meson: aiu: select REGMAP_MMIO

[Jude Gyimah]

gx-formatter.o is part of snd-soc-meson-aiu:

  sound/soc/meson/Makefile:7: snd-soc-meson-aiu-y += gx-formatter.o

so SND_MESON_AIU is the option that decides where its call lands,
and the error below names gx-formatter.c rather than aiu.c.

aiu calls __devm_regmap_init_mmio_clk, which
drivers/base/regmap/regmap-mmio.c provides under REGMAP_MMIO.

  gx-formatter.c:(.text+0x74): undefined reference to
    `__devm_regmap_init_mmio_clk'

The driver can be built into vmlinux while REGMAP_MMIO is a module, in
which case the symbol is not there at link time.

Select rather than depend on: REGMAP_MMIO has no prompt of its own and is
only ever enabled by a select, so a depends on would leave SND_MESON_AIU
unselectable.

Reproduced on v7.3, arm64, with CONFIG_SND_MESON_AIU=y and
CONFIG_REGMAP_MMIO=m.

Found with kreach, a static check that compares what Kconfig allows
against the symbols the compiled objects actually reference.

Fixes: 6ae9ca9ce986 ("ASoC: meson: aiu: add i2s and spdif support")
Signed-off-by: Jude Gyimah <jude.gyimah87@xxxxxxxxx>
Reviewed-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
Reviewed-by: Valerio Setti <vsetti@xxxxxxxxxxxx>
---
 sound/soc/meson/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sound/soc/meson/Kconfig b/sound/soc/meson/Kconfig
index d9a730994a2a..d0f60f8af2b5 100644
--- a/sound/soc/meson/Kconfig
+++ b/sound/soc/meson/Kconfig
@@ -4,6 +4,7 @@ menu "Amlogic"
 
 config SND_MESON_AIU
 	tristate "Amlogic AIU"
+	select REGMAP_MMIO
 	select SND_MESON_CODEC_GLUE
 	select SND_PCM_IEC958
 	imply SND_SOC_MESON_T9015
-- 
2.43.0