On Tue, Aug 13, 2019 at 09:22:29AM -0500, Pierre-Louis Bossart wrote:
On 8/13/19 1:10 AM, Nathan Chancellor wrote:
clang warns when CONFIG_ACPI is unset:
../drivers/soundwire/slave.c:16:12: warning: unused function 'sdw_slave_add' [-Wunused-function] static int sdw_slave_add(struct sdw_bus *bus, ^ 1 warning generated.
Before commit 8676b3ca4673 ("soundwire: fix regmap dependencies and align with other serial links"), this code would only be compiled when ACPI was set because it was only selected by SOUNDWIRE_INTEL, which depends on ACPI.
Now, this code can be compiled without CONFIG_ACPI, which causes the above warning. The IS_ENABLED(CONFIG_ACPI) guard could be moved to avoid compiling the function; however, slave.c only contains three functions, two of which are static. Only compile slave.o when CONFIG_ACPI is set, where it will actually be used. bus.h contains a stub for sdw_acpi_find_slaves so there will be no issues with an undefined function.
This has been build tested with CONFIG_ACPI set and unset in combination with CONFIG_SOUNDWIRE unset, built in, and a module.
Thanks for the patch. Do you have a .config you can share offline so that we add it to our tests?
I just took the arm64 defconfig and deleted CONFIG_ACPI and added CONFIG_SOUNDWIRE=y or =m to produce this warning. I initially found this on an arm64 allyesconfig build.
Fixes: 8676b3ca4673 ("soundwire: fix regmap dependencies and align with other serial links") Link: https://github.com/ClangBuiltLinux/linux/issues/637 Signed-off-by: Nathan Chancellor natechancellor@gmail.com
drivers/soundwire/Makefile | 6 +++++- drivers/soundwire/slave.c | 3 --- 2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile index 45b7e5001653..226090902716 100644 --- a/drivers/soundwire/Makefile +++ b/drivers/soundwire/Makefile @@ -4,9 +4,13 @@ # #Bus Objs -soundwire-bus-objs := bus_type.o bus.o slave.o mipi_disco.o stream.o +soundwire-bus-objs := bus_type.o bus.o mipi_disco.o stream.o obj-$(CONFIG_SOUNDWIRE) += soundwire-bus.o +ifdef CONFIG_ACPI +soundwire-bus-objs += slave.o +endif
I am fine with the change, but we might as well rename the file acpi_slave.c then?
Sure, I can do that rename and send a v2.
- #Cadence Objs soundwire-cadence-objs := cadence_master.o obj-$(CONFIG_SOUNDWIRE_CADENCE) += soundwire-cadence.o
diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c index f39a5815e25d..0dc188e6873b 100644 --- a/drivers/soundwire/slave.c +++ b/drivers/soundwire/slave.c @@ -60,7 +60,6 @@ static int sdw_slave_add(struct sdw_bus *bus, return ret; } -#if IS_ENABLED(CONFIG_ACPI) /*
- sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node
- @bus: SDW bus instance
@@ -110,5 +109,3 @@ int sdw_acpi_find_slaves(struct sdw_bus *bus) return 0; }
-#endif