Re: [PATCH net-next] net: dsa: hellcreek: Add missing TAPRIO dependency

[Randy Dunlap <rdunlap@infradead.org>]

On 1/28/21 8:33 AM, Kurt Kanzenbach wrote:
> Add missing dependency to TAPRIO to avoid build failures such as:
> 
> |ERROR: modpost: "taprio_offload_get" [drivers/net/dsa/hirschmann/hellcreek_sw.ko] undefined!
> |ERROR: modpost: "taprio_offload_free" [drivers/net/dsa/hirschmann/hellcreek_sw.ko] undefined!
> 
> Fixes: 24dfc6eb39b2 ("net: dsa: hellcreek: Add TAPRIO offloading support")
> Reported-by: Randy Dunlap <rdunlap@infradead.org>
> Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
> ---
>  drivers/net/dsa/hirschmann/Kconfig | 1 +
>  1 file changed, 1 insertion(+)
> 
> Note: It's not against net, because the fixed commit is not in net tree, yet.
> 
> diff --git a/drivers/net/dsa/hirschmann/Kconfig b/drivers/net/dsa/hirschmann/Kconfig
> index e01191107a4b..9ea2c643f8f8 100644
> --- a/drivers/net/dsa/hirschmann/Kconfig
> +++ b/drivers/net/dsa/hirschmann/Kconfig
> @@ -5,6 +5,7 @@ config NET_DSA_HIRSCHMANN_HELLCREEK
>  	depends on NET_DSA
>  	depends on PTP_1588_CLOCK
>  	depends on LEDS_CLASS
> +	depends on NET_SCH_TAPRIO
>  	select NET_DSA_TAG_HELLCREEK
>  	help
>  	  This driver adds support for Hirschmann Hellcreek TSN switches.
> 

Thanks. This fixes the build errors.
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
 

However, I do see this in the build output when
NET_DSA_HIRSCHMANN_HELLCREEK is disabled:

  AR      drivers/net/dsa/hirschmann/built-in.a

That is an empty archive file (8 bytes), which is caused by
drivers/net/dsa/Makefile:

obj-y				+= hirschmann/


Is there some reason that it's not done like this?
This passes my y/m/n testing.

---
From: Randy Dunlap <rdunlap@infradead.org>

This prevents descending into the net/dsa/hirschmann/ subdirectory
and building an empty archive file:

  AR      drivers/net/dsa/hirschmann/built-in.a

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
---
 drivers/net/dsa/Makefile |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- linux-next-20210128.orig/drivers/net/dsa/Makefile
+++ linux-next-20210128/drivers/net/dsa/Makefile
@@ -18,7 +18,7 @@ obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX) +=
 obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX_PLATFORM) += vitesse-vsc73xx-platform.o
 obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX_SPI) += vitesse-vsc73xx-spi.o
 obj-y				+= b53/
-obj-y				+= hirschmann/
+obj-$(CONFIG_NET_DSA_HIRSCHMANN_HELLCREEK) += hirschmann/
 obj-y				+= microchip/
 obj-y				+= mv88e6xxx/
 obj-y				+= ocelot/