[RFC PATCH] kernel: zstd: enable crypto API support on Linux 4.19+

[Rui Salvaterra]

Zstd is supported by the crypto API since Linux 4.18. Enable this feature and
reveal the package in the configuration section, so the user can select it.
This allows zstd to be used as a compression algorithm in zram, for example.

Signed-off-by: Rui Salvaterra <rsalvaterra at gmail.com>
---
 package/kernel/linux/modules/lib.mk | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/package/kernel/linux/modules/lib.mk b/package/kernel/linux/modules/lib.mk
index 1289cc1f25..143ce7e62d 100644
--- a/package/kernel/linux/modules/lib.mk
+++ b/package/kernel/linux/modules/lib.mk
@@ -124,16 +124,18 @@ $(eval $(call KernelPackage,lib-lzo))
 define KernelPackage/lib-zstd
   SUBMENU:=$(LIB_MENU)
   TITLE:=ZSTD support
+  DEPENDS:=+!LINUX_4_14:kmod-crypto-acompress
   KCONFIG:= \
+	CONFIG_CRYPTO_ZSTD \
 	CONFIG_ZSTD_COMPRESS \
 	CONFIG_ZSTD_DECOMPRESS \
 	CONFIG_XXHASH
-  HIDDEN:=1
   FILES:= \
+	$(LINUX_DIR)/crypto/zstd.ko at ge4.19 \
 	$(LINUX_DIR)/lib/xxhash.ko \
 	$(LINUX_DIR)/lib/zstd/zstd_compress.ko \
 	$(LINUX_DIR)/lib/zstd/zstd_decompress.ko
-  AUTOLOAD:=$(call AutoProbe,xxhash zstd_compress zstd_decompress)
+  AUTOLOAD:=$(call AutoProbe,xxhash zstd zstd_compress zstd_decompress)
 endef
 
 define KernelPackage/lib-zstd/description
-- 
2.27.0