With posix timers having become optional, we get a build error with the cpts time sync option of the CPSW driver: drivers/net/ethernet/ti/cpts.c: In function 'cpts_find_ts': drivers/net/ethernet/ti/cpts.c:291:23: error: implicit declaration of function 'ptp_classify_raw';did you mean 'ptp_classifier_init'? [-Werror=implicit-function-declaration] It really makes no sense to build this driver if we can't use PTP, so it's better to go back to 'select PTP_1588_CLOCK' but instead add a dependency on POSIX_TIMERS. Adding 'depends on PTP_1588_CLOCK' might also work, but has the risk of circular dependencies when mixed with other drivers using 'imply'. Fixes: baa73d9e478f ("posix-timers: Make them configurable") Cc: Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- Originally submitted on Dec 16, but not applied after I missed a reply from Nico. I confirmed that this is still needed for v4.10 and v4.11-rc2 and am resending it without changes. --- drivers/net/ethernet/ti/Kconfig | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig index d42257fbe9d9..c114efcd1575 100644 --- a/drivers/net/ethernet/ti/Kconfig +++ b/drivers/net/ethernet/ti/Kconfig @@ -76,7 +76,8 @@ config TI_CPSW config TI_CPTS_ENABLE bool "TI Common Platform Time Sync (CPTS) Support" depends on TI_CPSW || TI_KEYSTONE_NETCP - imply PTP_1588_CLOCK + depends on POSIX_TIMERS + select PTP_1588_CLOCK ---help--- This driver supports the Common Platform Time Sync unit of the CPSW Ethernet Switch and Keystone 2 1g/10g Switch Subsystem. -- 2.9.0