Subject: Re: [alsa-devel] [PATCH v5 08/11] ASoC: Intel: atom: Make PCI dependency explicit

From: Pierre-Louis Bossart <[email-masked]>
Date: Wed, 2 Jan 2019 14:33:06 -0600

I have three opens with this ACPI/PCI change

1. the baseline change fails on my cross-compilation checks, see below 
the result of the attached script (simplification of the one I use to 
avoid 0day reports).

2. there are different patterns to express the dependency on PCI e.g.

  config MMC_SDHCI_ACPI
      tristate "SDHCI support for ACPI enumerated SDHCI controllers"
      depends on MMC_SDHCI && ACPI
-    select IOSF_MBI if X86
+    select IOSF_MBI if (X86 && PCI)

but

config SND_SST_ATOM_HIFI2_PLATFORM_ACPI
      tristate "ACPI HiFi2 (Baytrail, Cherrytrail) Platforms"
      default ACPI
-    depends on X86 && ACPI
+    depends on X86 && ACPI && PCI
      select SND_SST_IPC_ACPI
      select SND_SST_ATOM_HIFI2_PLATFORM
      select SND_SOC_ACPI_INTEL_MATCH

IOSF is only needed for Baytrail-CR detection, and the code will compile 
fine without it, so maybe it'd be a better model if you used the 
following diff?

diff --git a/sound/soc/intel/Kconfig b/sound/soc/intel/Kconfig
index 2fd1b61e8331..68af0ea5c96c 100644
--- a/sound/soc/intel/Kconfig
+++ b/sound/soc/intel/Kconfig
@@ -95,7 +95,7 @@ config SND_SST_ATOM_HIFI2_PLATFORM_ACPI
         select SND_SST_IPC_ACPI
         select SND_SST_ATOM_HIFI2_PLATFORM
         select SND_SOC_ACPI_INTEL_MATCH
-       select IOSF_MBI
+       select IOSF_MBI if PCI

3. All the Intel machine drivers depend on X86_INTEL_LPSS which depends 
on PCI. But for Baytrail/Haswell/Broadwell we have only a dependency on 
ACPI, so we expose drivers that can be selected but fail on probe since 
there are no machine drivers. I am not sure if we want to be strict and 
only expose meaningful configurations, or allow for more compilations 
tests and corner cases?

-Pierre

cross-compilation issue:

git checkout next-20190102

make CROSS_COMPILE=/opt/gcc-8.1.0-nolibc/ia64-linux/bin/ia64-linux- 
--jobs=16 allmodconfig ARCH=ia64
   HOSTCC  scripts/basic/fixdep
   HOSTCC  scripts/kconfig/conf.o
   YACC    scripts/kconfig/zconf.tab.c
   LEX     scripts/kconfig/zconf.lex.c
   HOSTCC  scripts/kconfig/confdata.o
   HOSTCC  scripts/kconfig/expr.o
   HOSTCC  scripts/kconfig/symbol.o
   YACC    scripts/kconfig/zconf.tab.h
   HOSTCC  scripts/kconfig/preprocess.o
   HOSTCC  scripts/kconfig/zconf.tab.o
   HOSTCC  scripts/kconfig/zconf.lex.o
   HOSTLD  scripts/kconfig/conf
scripts/kconfig/conf  --allmodconfig Kconfig
arch/ia64/Kconfig:128:error: recursive dependency detected!
arch/ia64/Kconfig:128:    choice <choice> contains symbol IA64_HP_SIM
arch/ia64/Kconfig:202:    symbol IA64_HP_SIM is part of choice PM
kernel/power/Kconfig:144:    symbol PM is selected by PM_SLEEP
kernel/power/Kconfig:104:    symbol PM_SLEEP depends on HIBERNATE_CALLBACKS
kernel/power/Kconfig:31:    symbol HIBERNATE_CALLBACKS is selected by 
HIBERNATION
kernel/power/Kconfig:34:    symbol HIBERNATION depends on SWAP
init/Kconfig:250:    symbol SWAP depends on BLOCK
block/Kconfig:5:    symbol BLOCK is selected by UBIFS_FS
fs/ubifs/Kconfig:1:    symbol UBIFS_FS depends on MISC_FILESYSTEMS
fs/Kconfig:227:    symbol MISC_FILESYSTEMS is selected by ACPI_APEI
drivers/acpi/apei/Kconfig:8:    symbol ACPI_APEI depends on ACPI
drivers/acpi/Kconfig:9:    symbol ACPI depends on ARCH_SUPPORTS_ACPI
drivers/acpi/Kconfig:6:    symbol ARCH_SUPPORTS_ACPI is selected by 
IA64_HP_SIM
arch/ia64/Kconfig:202:    symbol IA64_HP_SIM is part of choice <choice>
For a resolution refer to Documentation/kbuild/kconfig-language.txt
subsection "Kconfig recursive dependency limitations"