From d1cbfd771ce8297fa11e89f315392de6056a2181 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Fri, 11 Nov 2016 00:10:07 -0500 Subject: ptp_clock: Allow for it to be optional In order to break the hard dependency between the PTP clock subsystem and ethernet drivers capable of being clock providers, this patch provides simple PTP stub functions to allow linkage of those drivers into the kernel even when the PTP subsystem is configured out. Drivers must be ready to accept NULL from ptp_clock_register() in that case. And to make it possible for PTP to be configured out, the select statement in those driver's Kconfig menu entries is converted to the new "imply" statement. This way the PTP subsystem may have Kconfig dependencies of its own, such as POSIX_TIMERS, without having to make those ethernet drivers unavailable if POSIX timers are cconfigured out. And when support for POSIX timers is selected again then the default config option for PTP clock support will automatically be adjusted accordingly. The pch_gbe driver is a bit special as it relies on extra code in drivers/ptp/ptp_pch.c. Therefore we let the make process descend into drivers/ptp/ even if PTP_1588_CLOCK is unselected. Signed-off-by: Nicolas Pitre Acked-by: Richard Cochran Acked-by: Edward Cree Acked-by: Thomas Gleixner Acked-by: John Stultz Reviewed-by: Josh Triplett Cc: Paul Bolle Cc: linux-kbuild@vger.kernel.org Cc: netdev@vger.kernel.org Cc: Michal Marek Link: http://lkml.kernel.org/r/1478841010-28605-4-git-send-email-nicolas.pitre@linaro.org Signed-off-by: Thomas Gleixner --- drivers/net/ethernet/tile/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/ethernet/tile') diff --git a/drivers/net/ethernet/tile/Kconfig b/drivers/net/ethernet/tile/Kconfig index f59a6c265331..bdfeaf3d4fce 100644 --- a/drivers/net/ethernet/tile/Kconfig +++ b/drivers/net/ethernet/tile/Kconfig @@ -9,7 +9,7 @@ config TILE_NET select CRC32 select TILE_GXIO_MPIPE if TILEGX select HIGH_RES_TIMERS if TILEGX - select PTP_1588_CLOCK if TILEGX + imply PTP_1588_CLOCK if TILEGX ---help--- This is a standard Linux network device driver for the on-chip Tilera Gigabit Ethernet and XAUI interfaces. -- cgit v1.2.3