发布时间：2015-07-04 01:23:29
<p>The Linux USB subsystem has grown fromsupporting only two different types of devices in the 2.2.7 kernel(mice and keyboards), to over 20 different types of devices in the2.4 kernel. Linux currently supports almost all USB class devices(standard types of devices like keyboards, mice, modems,.........【阅读全文】
发布时间：2015-07-04 01:13:04
<strong>1. What is composite device</strong><br />Composite device is defined in the USB spec as follows (usb_20.pdf 5.2.3),<br /><em>"A device that has multiple interfaces controlled independently of each other is referred to as a composite device."</em> <p>Using composite device, multip.........【阅读全文】
发布时间：2015-07-04 00:42:05
Gadget 功能层 Gadget功能层完成USB设备的具体功能，其表现的形式各不相同，如键盘、鼠标、存储和网卡等等。功能层不仅涉及到Gadget驱动相关的内容，还涉及到其功能相关的内核子系统。如存储还涉及到内核存储子系统，网卡还涉及到网络驱动子系统。因此，Gadget功能的代码非常复杂。这里以zero.c为例，这个模块只是简单地将.........【阅读全文】
