usb: gadget: f_subset: add configfs support

f_subset learns about configfs so we can, eventually,
remove in-kernel gadget drivers.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index 0a444f39109f..3a72b9dbf7f0 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -547,6 +547,16 @@ choice
 
 # this first set of drivers all depend on bulk-capable hardware.
 
+config USB_CONFIGFS_ECM_SUBSET
+        boolean "Ethernet Control Model (CDC ECM) subset"
+        depends on USB_CONFIGFS
+        depends on NET
+        select USB_U_ETHER
+        select USB_F_SUBSET
+        help
+          On hardware that can't implement the full protocol,
+          a simple CDC subset is used, placing fewer demands on USB.
+
 config USB_CONFIGFS_EEM
         bool "Ethernet Emulation Model (EEM)"
         depends on USB_CONFIGFS