展锐8541E配置USB ACM

1、kernel config 参考如下修改
cd bsp
source build/envsetup.sh
lunch 34
kuconfig -> Device Drivers  ---> USB support  ---> USB Gadget Support  --->  [*]     Abstract Control Model (CDC ACM)

--- kernel/kernel4.14/arch/arm/configs/sprd_sharkle_defconfig   (revision 226)
+++ kernel/kernel4.14/arch/arm/configs/sprd_sharkle_defconfig   (working copy)
@@ -2987,6 +2996,7 @@
 # CONFIG_USB_GADGET_XILINX is not set
 # CONFIG_USB_DUMMY_HCD is not set
 CONFIG_USB_LIBCOMPOSITE=y
+CONFIG_USB_F_ACM=y
 CONFIG_USB_U_SERIAL=y
 CONFIG_USB_U_ETHER=y
 CONFIG_USB_F_SERIAL=y
@@ -3001,7 +3011,7 @@
 CONFIG_USB_F_VSERIAL=y
 CONFIG_USB_CONFIGFS=y
 CONFIG_USB_CONFIGFS_SERIAL=y
-# CONFIG_USB_CONFIGFS_ACM is not set
+CONFIG_USB_CONFIGFS_ACM=y
 # CONFIG_USB_CONFIGFS_OBEX is not set
 # CONFIG_USB_CONFIGFS_NCM is not set
 # CONFIG_USB_CONFIGFS_ECM is not set


2、为了不占用基线已有的USB串口，增大USB串口支持的最大数目
--- bsp/kernel/kernel4.14/drivers/usb/gadget/function/u_serial.h        (revision 226)
+++ bsp/kernel/kernel4.14/drivers/usb/gadget/function/u_serial.h        (working copy)
@@ -15,7 +15,7 @@
 #include <linux/usb/composite.h>
 #include <linux/usb/cdc.h>

-#define MAX_U_SERIAL_PORTS     8
+#define MAX_U_SERIAL_PORTS     10

 struct f_serial_opts {
        struct usb_function_instance func_inst;


3、init.common.usb.rc 参考如下修改（完整路径以sharkle为例：device/sprd/sharkle/common/rootdir/root/init.common.usb.rc）
on init
...
    mkdir /config/usb_gadget/g1/functions/mass_storage.gs6 0770 shell shell
    mkdir /config/usb_gadget/g1/functions/gser.gs0 0770 shell shell
    mkdir /config/usb_gadget/g1/functions/gser.gs1 0770 shell shell
    mkdir /config/usb_gadget/g1/functions/gser.gs2 0770 shell shell
    mkdir /config/usb_gadget/g1/functions/gser.gs3 0770 shell shell
    mkdir /config/usb_gadget/g1/functions/gser.gs4 0770 shell shell
    mkdir /config/usb_gadget/g1/functions/gser.gs5 0770 shell shell
    mkdir /config/usb_gadget/g1/functions/gser.gs6 0770 shell shell
    mkdir /config/usb_gadget/g1/functions/gser.gs7 0770 shell shell
+    mkdir /config/usb_gadget/g1/functions/acm.gs0 0770 shell shell
+    mkdir /config/usb_gadget/g1/functions/acm.gs1 0770 shell shell

    setprop sys.usb.mode normal

+ # 新增