Documentation-usb-dwc3.txt

Chinese translated version of Documentation/usb/dwc3.txt


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Maintainer: Eric W. Biederman <[e-mail]>
Chinese maintainer: Shao Qi <[e-mail]>
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Documentation/usb/dwc3.txt 的中文翻译


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英文版维护者： Eric W. Biederman <[e-mail]>
中文版维护者： 邵奇 Shao Qi <[e-mail]>
中文版翻译者： 邵奇 Shao Qi <[e-mail]>
中文版校译者： 邵奇 Shao Qi <[e-mail]>


以下为正文
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TODO
备忘录
~~~~~~
Please pick something while reading :)
在阅读时请整理一下 :)


- Convert interrupt handler to per-ep-thread-irq
- 转换中断处理程序到per-ep-thread-irq


  As it turns out some DWC3-commands ~1ms to complete. Currently we spin
  until the command completes which is bad.
  当一些DWC3命令要1ms完成。当前，知道坏命令完成之后才回转。
  
  Implementation idea:
  实现思路：
  - dwc core implements a demultiplexing irq chip for interrupts per
    endpoint. The interrupt numbers are allocated during probe and belong
    to the device. If MSI provides per-endpoint interrupt this dummy
    interrupt chip can be replaced with "real" interrupts.
  - dwc核心实现多路解编IRQ芯片来终端每一个末端。终端号在探测期间被分配，并归属于
    此设备。如果MSI提供每个端点中断功能，此虚拟中断芯片能被真正的中断代替。
  
  - interrupts are requested / allocated on usb_ep_enable() and removed on
    usb_ep_disable(). Worst case are 32 interrupts, the lower limit is two
    for ep0/1.
  - 中断在usb_ep_enable()被请求/分配,在 usb_ep_disable()被移除。最坏的情况是
    32个中断，下限为2个ep0/1.

  - dwc3_send_gadget_ep_cmd() will sleep in wait_for_completion_timeout()
    until the command completes.
  - dwc3_send_gadget_ep_cmd()将在wait_for_completion_timeout()完成之前休眠。
  
  - the interrupt handler is split into the following pieces:
  - 中断处理程序被分成以下几部分：
    - primary handler of the device
      goes through every event and calls generic_handle_irq() for event
      it. On return from generic_handle_irq() in acknowledges the event
      counter so interrupt goes away (eventually).
    - 主处理设备
 参加每一个事件，调用generic_handle_irq()来通知。在generic_handle_irq()
      返回时认可事件计数器，最终中断消失。  
    - threaded handler of the device
      none
- 线程处理设备
 无


    - primary handler of the EP-interrupt
      reads the event and tries to process it. Everything that requires
      sleeping is handed over to the Thread. The event is saved in an
      per-endpoint data-structure.
      We probably have to pay attention not to process events once we
      handed something to thread so we don't process event X prio Y
      where X > Y.
- EP中断的主处理器
 读取事件并尝试处理它。所有请求休眠的事件被移交给线程。此事件被保存
 在一个per-endpoint数据结构中。
 我们可能不得不注意，一旦我们移交东西给线程，不能去处理事件。所以当
 X > Y 时我们不能处理事件X prio Y。


    - threaded handler of the EP-interrupt
      handles the remaining EP work which might sleep such as waiting
      for command completion.
    - EP中断的线程级处理器
 处理余下的可能休眠的EP工作，比如等待命令完成。
  Latency:
   There should be no increase in latency since the interrupt-thread has a
   high priority and will be run before an average task in user land
  (except the user changed priorities).
  延迟：
  由于中断线程有高优先级，所以不该增加延迟。并且在用户范围的平均任务之前运行
  （除非用户改变优先级）。