On 05.04.2024 16:27, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@xxxxxxxx> > > When I2C_MUX is a loadable module but I2C_I801 is built-in, the newly > added notifier function causes a link error: > > x86_64-linux-ld: drivers/i2c/busses/i2c-i801.o: in function `i801_notifier_call': > i2c-i801.c:(.text+0x1f5): undefined reference to `i2c_root_adapter' > > This code is only built if I2C_MUX_GPIO is also enabled, so add a > conditional dependency that allows building the driver as before if the > GPIO part is disabled, but otherwise require the linker dependency at > Kconfig level. > > With the added dependency, the driver cannot be selected by a builtin > ITCO_WDT driver when I2C_MUX_GPIO is a loadable module, so remove > the 'select' statement in that driver as well. This was apparently > never needed at compile-time, and the watchdog driver just needs either > the LPC or the I2C drivers, but never both. > > Configurations that rely on the implied 'select' from the watchdog > driver now need to enable all three. > Question is whether we really want that I2C_MUX restricts the choice for I2C_I801. Alternatively we can skip building the mux part in the problem case. The mux part can be used on very few old Asus systems with > 8 memory slots only. Proposal I sent: https://lore.kernel.org/all/4dhfyaefnw2rtx5q7aaum6pfwha5o3vs65iqcrj2ghps34ubtw@b3bw3gggudjs/T/ Note also the CI bot tags, as the problem was reported by a CI bot before. > Fixes: 71b494e043d2 ("i2c: i801: Call i2c_register_spd for muxed child segments") > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> > --- > drivers/i2c/busses/Kconfig | 1 + > drivers/watchdog/Kconfig | 2 -- > 2 files changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > index 1872f1995c77..2619018dd756 100644 > --- a/drivers/i2c/busses/Kconfig > +++ b/drivers/i2c/busses/Kconfig > @@ -108,6 +108,7 @@ config I2C_HIX5HD2 > config I2C_I801 > tristate "Intel 82801 (ICH/PCH)" > depends on PCI > + depends on I2C_MUX || I2C_MUX_GPIO=n > select P2SB if X86 > select CHECK_SIGNATURE if X86 && DMI > select I2C_SMBUS > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index 0b0df3fe1efd..4dfb3773e6e2 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -1301,8 +1301,6 @@ config ITCO_WDT > select WATCHDOG_CORE > depends on I2C || I2C=n > depends on MFD_INTEL_PMC_BXT || !MFD_INTEL_PMC_BXT > - select LPC_ICH if !EXPERT > - select I2C_I801 if !EXPERT && I2C > help > Hardware driver for the intel TCO timer based watchdog devices. > These drivers are included in the Intel 82801 I/O Controller
