ea4367c40c
When building with CONFIG_SYSFS=n, the build error below is triggered: ld: drivers/power/supply/power_supply_core.o:(.data+0x0): undefined reference to `power_supply_attr_group' The problem is that power_supply_attr_group is needed in power_supply_core.c but defined in power_supply_sysfs.c, which is only targeted with CONFIG_SYSFS=y. Therefore, move the extern declaration into the #ifdef block that checks for CONFIG_SYSFS, and define an empty static const struct otherwise. This is safe because the macro __ATRIBUTE_GROUPS in power_supply_core.c will expand into an empty attribute_group array. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reported-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/all/20240227214916.GA3699076@dev-arch.thelio-3990X/ Fixes: 7b46b60944d7 ("power: supply: core: constify the struct device_type usage") Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net> Tested-by: Nathan Chancellor <nathan@kernel.org> # build Link: https://lore.kernel.org/r/20240228-device_cleanup-power-v1-1-52c0321c48e1@marliere.net Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>