kernel: add exfat again

With kernel 5.10, exfat is out of staging and in tree.

Added small hack to make it work with kernel 5.4 as well.

Added removed config options for 5.4 to generic config.

Signed-off-by: Rosen Penev <[email protected]>
[Set CONFIG_EXFAT_ config options to default values]
Signed-off-by: Hauke Mehrtens <[email protected]>

package/kernel/linux/modules/fs.mk

@@ -164,6 +164,26 @@ endef
 $(eval $(call KernelPackage,fs-efivarfs))
 
 
+define KernelPackage/fs-exfat
+  SUBMENU:=$(FS_MENU)
+  TITLE:=exFAT filesystem support
+  KCONFIG:= \
+	CONFIG_EXFAT_FS \
+	CONFIG_EXFAT_DEFAULT_IOCHARSET="utf8"
+  FILES:= \
+	$(LINUX_DIR)/drivers/staging/exfat/[email protected] \
+	$(LINUX_DIR)/fs/exfat/[email protected]
+  AUTOLOAD:=$(call AutoLoad,30,exfat,1)
+  DEPENDS:=+kmod-nls-base
+endef
+
+define KernelPackage/fs-exfat/description
+ Kernel module for exFAT filesystem support
+endef
+
+$(eval $(call KernelPackage,fs-exfat))
+
+
 define KernelPackage/fs-exportfs
   SUBMENU:=$(FS_MENU)
   TITLE:=exportfs kernel server support

target/linux/generic/config-5.4

@@ -1506,7 +1506,13 @@ CONFIG_ETHERNET=y
 # CONFIG_ETHOC is not set
 CONFIG_EVENTFD=y
 # CONFIG_EVM is not set
+# CONFIG_EXFAT_DEBUG_MSG is not set
+CONFIG_EXFAT_DEFAULT_CODEPAGE=437
+# CONFIG_EXFAT_DELAYED_SYNC is not set
+CONFIG_EXFAT_DISCARD=y
+CONFIG_EXFAT_DONT_MOUNT_VFAT=y
 # CONFIG_EXFAT_FS is not set
+# CONFIG_EXFAT_KERNEL_DEBUG is not set
 CONFIG_EXPERT=y
 CONFIG_EXPORTFS=y
 # CONFIG_EXPORTFS_BLOCK_OPS is not set