From b6d49cab44b567b3e0a5544b3d61e516a7355fad Mon Sep 17 00:00:00 2001 From: Clay McClure Date: Wed, 29 Apr 2020 00:59:00 -0700 Subject: net: Make PTP-specific drivers depend on PTP_1588_CLOCK Commit d1cbfd771ce8 ("ptp_clock: Allow for it to be optional") changed all PTP-capable Ethernet drivers from `select PTP_1588_CLOCK` to `imply PTP_1588_CLOCK`, "in order to break the hard dependency between the PTP clock subsystem and ethernet drivers capable of being clock providers." As a result it is possible to build PTP-capable Ethernet drivers without the PTP subsystem by deselecting PTP_1588_CLOCK. Drivers are required to handle the missing dependency gracefully. Some PTP-capable Ethernet drivers (e.g., TI_CPSW) factor their PTP code out into separate drivers (e.g., TI_CPTS_MOD). The above commit also changed these PTP-specific drivers to `imply PTP_1588_CLOCK`, making it possible to build them without the PTP subsystem. But as Grygorii Strashko noted in [1]: On Wed, Apr 22, 2020 at 02:16:11PM +0300, Grygorii Strashko wrote: > Another question is that CPTS completely nonfunctional in this case and > it was never expected that somebody will even try to use/run such > configuration (except for random build purposes). In my view, enabling a PTP-specific driver without the PTP subsystem is a configuration error made possible by the above commit. Kconfig should not allow users to create a configuration with missing dependencies that results in "completely nonfunctional" drivers. I audited all network drivers that call ptp_clock_register() but merely `imply PTP_1588_CLOCK` and found five PTP-specific drivers that are likely nonfunctional without PTP_1588_CLOCK: NET_DSA_MV88E6XXX_PTP NET_DSA_SJA1105_PTP MACB_USE_HWSTAMP CAVIUM_PTP TI_CPTS_MOD Note how these symbols all reference PTP or timestamping in their name; this is a clue that they depend on PTP_1588_CLOCK. Change them from `imply PTP_1588_CLOCK` [2] to `depends on PTP_1588_CLOCK`. I'm not using `select PTP_1588_CLOCK` here because PTP_1588_CLOCK has its own dependencies, which `select` would not transitively apply. Additionally, remove the `select NET_PTP_CLASSIFY` from CPTS_TI_MOD; PTP_1588_CLOCK already selects that. [1]: https://lore.kernel.org/lkml/c04458ed-29ee-1797-3a11-7f3f560553e6@ti.com/ [2]: NET_DSA_SJA1105_PTP had never declared any type of dependency on PTP_1588_CLOCK (`imply` or otherwise); adding a `depends on PTP_1588_CLOCK` here seems appropriate. Cc: Arnd Bergmann Cc: Richard Cochran Cc: Nicolas Pitre Cc: Grygorii Strashko Cc: Geert Uytterhoeven Fixes: d1cbfd771ce8 ("ptp_clock: Allow for it to be optional") Signed-off-by: Clay McClure Signed-off-by: David S. Miller --- drivers/net/ethernet/cadence/Kconfig | 2 +- drivers/net/ethernet/cavium/Kconfig | 2 +- drivers/net/ethernet/ti/Kconfig | 3 +-- 3 files changed, 3 insertions(+), 4 deletions(-) (limited to 'drivers/net/ethernet') diff --git a/drivers/net/ethernet/cadence/Kconfig b/drivers/net/ethernet/cadence/Kconfig index 53b50c24d9c9..2c4c12b03502 100644 --- a/drivers/net/ethernet/cadence/Kconfig +++ b/drivers/net/ethernet/cadence/Kconfig @@ -35,8 +35,8 @@ config MACB config MACB_USE_HWSTAMP bool "Use IEEE 1588 hwstamp" depends on MACB + depends on PTP_1588_CLOCK default y - imply PTP_1588_CLOCK ---help--- Enable IEEE 1588 Precision Time Protocol (PTP) support for MACB. diff --git a/drivers/net/ethernet/cavium/Kconfig b/drivers/net/ethernet/cavium/Kconfig index 6a700d34019e..4520e7ee00fe 100644 --- a/drivers/net/ethernet/cavium/Kconfig +++ b/drivers/net/ethernet/cavium/Kconfig @@ -54,7 +54,7 @@ config THUNDER_NIC_RGX config CAVIUM_PTP tristate "Cavium PTP coprocessor as PTP clock" depends on 64BIT && PCI - imply PTP_1588_CLOCK + depends on PTP_1588_CLOCK ---help--- This driver adds support for the Precision Time Protocol Clocks and Timestamping coprocessor (PTP) found on Cavium processors. diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig index 89cec778cf2d..8e348780efb6 100644 --- a/drivers/net/ethernet/ti/Kconfig +++ b/drivers/net/ethernet/ti/Kconfig @@ -90,9 +90,8 @@ config TI_CPTS config TI_CPTS_MOD tristate depends on TI_CPTS + depends on PTP_1588_CLOCK default y if TI_CPSW=y || TI_KEYSTONE_NETCP=y || TI_CPSW_SWITCHDEV=y - select NET_PTP_CLASSIFY - imply PTP_1588_CLOCK default m config TI_K3_AM65_CPSW_NUSS -- cgit v1.2.3