USB fastboot

1 Samsung
fastboot flashing unlock

2 bootloader增加解锁密码
diff --git a/app/aboot/aboot.c b/app/aboot/aboot.c

index e4d46e4..1b4b450 100755
--- a/app/aboot/aboot.c
+++ b/app/aboot/aboot.c
@@ -2613,6 +2613,20 @@ void cmd_oem_unlock(const char *arg,
    void *data, unsigned sz)

void cmd_oem_unlock_go(const char *arg,
        void *data, unsigned sz)
 {
+        // oem-start
+        char *p = (char *)arg;
+        if (!arg) {
+            fastboot_fail(
+            "[oem] key in password please,
+            \"fastboot oem unlock-go [pwd]\"");
+            return;
+        }
+
+        while (isspace(*p)) p++;
+        if (strncmp(p, "12345678",
+            strlen("12345678"))) {
+                fastboot_fail(
+                "[oem] wrong password,
+                \"fastboot oem unlock-go [pwd]\"");
+                return;
+        }
+        // oem-end
+
Fastboot command call chain as shown below, from the viewpoint of device-side.
Figure 1-1 Fastboot Command Call Chain

3 Abbreviations
ARC：Argonant RISC Core
AT91SAM9260：SAM means Smart ARM-based
ATMEL SAMBA：ATMEL Smart ARM-based Boot Assistant
DWC2：Design Ware Controller 2，Apple的嵌入式设备，包括iPad和iPhone都是使用的DWC2
ISP1161：Philips' Integrated host Solution Pairs 1161，“Firms introduce USB host controllers”，https://www.eetimes.com/document.asp?doc_id=1290054
SL811HS：Cypress/ScanLogic 811 Host/Slave，性能上与ISP1161（Integrated host Solution Pairs 1161）相当
TDI：TransDimension Inc.，该公司首先发明了将TT集成到EHCI RootHub中的方法，这样对于嵌入式系统来说，就省去了OHCI/UHCI的硬件，同时降低了成本，作为对该公司的纪念，Linux内核定义了宏ehci_is_TDI(ehci)
TT：Transaction Translator（事务转换器，将USB2.0的包转换成USB1.1的包）