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开始发布: 11_Gadget驱动程序框架
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BIN
IMX6ULL/doc_pic/12_USB/11.1_从硬件软件角度理解Gadget框架.tif
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IMX6ULL/doc_pic/12_USB/11.1_从硬件软件角度理解Gadget框架.tif
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@@ -13,377 +13,113 @@
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## 1. 笔记
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## 1. 怎样理解Gadget框架
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USB协议是主从结构：
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我们编写USB设备驱动程序时，主要是：
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```shell
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struct usb_gadget - represents a usb slave device
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struct usb_composite_device - represents one composite usb gadget
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struct usb_udc - describes one usb device controller
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```
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* 读取设备的各类描述符，比如endpoint描述符，得到端点号
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* 使用底层USB Host Controller驱动程序提供的API函数，从endpoint上读写数据
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那么要基于Gadget驱动框架模拟一个USB设备时，endpoint的数据传输能力是底层的USB Device Controller驱动提供的，我们要做的就是：
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* 提供各类设备描述符
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* 使用底层USB Device Controller驱动程序提供的API函数，从endpoint得到数据、反馈数据
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```c
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/**
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* struct usb_udc - describes one usb device controller
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* @driver - the gadget driver pointer. For use by the class code
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* @dev - the child device to the actual controller
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* @gadget - the gadget. For use by the class code
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* @list - for use by the udc class driver
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* @vbus - for udcs who care about vbus status, this value is real vbus status;
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* for udcs who do not care about vbus status, this value is always true
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*
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* This represents the internal data structure which is used by the UDC-class
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* to hold information about udc driver and gadget together.
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*/
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struct usb_udc {
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struct usb_gadget_driver *driver;
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struct usb_gadget *gadget;
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struct device dev;
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struct list_head list;
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bool vbus;
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};
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Gadget的含义是"小器件"，在Linux的USB系统中，它表示"usb device"。Gadget驱动程序，就是用来模拟USB Device。对于真实的USB Device，它有两大要素：
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* 怎么表示自己？
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* 每个USB Device都有1个设备描述符
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* 都1个或多个配置描述符
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* 每个配置描述符里面有1个或多个接口描述符
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* 每个接口描述符里面有0个多个端点描述符
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* 怎么进行数据传输？
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* 通过端点进行传输
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* 有端点的操作函数
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// usb_udc用来表示USB设备控制器，它里面有：
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// 1. usb_gadget : 用来表示硬件信息？represents a usb slave device，比如USB串口？
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// 2. usb_gadget_driver: 用来表示软件信息？driver for usb 'slave' devices
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```
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在学习过程中，记住这几个要点非常有帮助：
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usb_gadget和usb_composite_dev必定一起出现：usb_gadget描述的是硬件底层信息(?)，usb_composite_dev描述的是硬件的上层信息(？)
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* 各类描述符的构造
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* USB Host获得Gadget各类描述符的过程
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* 数据传输的流程
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## 2. 从硬件软件角度理解Gadget框架
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### 1.1 结构体
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USB传输的核心是endpoint，使用endpoint可以收发数据。在endpoint之上，就可以模拟USB串口、USB触碰屏、USB摄像头。基于这个角度，Gadget框架可以分为两层：
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```c
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struct usb_udc - describes one usb device controller
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struct usb_gadget - represents a usb slave device
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struct usb_gadget_driver - driver for usb 'slave' devices
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struct usb_composite_device - represents one composite usb gadget
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struct usb_function - describes one function of a configuration
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struct usb_composite_driver - groups configurations into a gadget
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```
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* 底层endpoint操作
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* 上层模拟各类USB设备
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对于底层endpoint的代码，需要从UDC驱动开始分析：
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* IMX6ULL的代码：`Linux-4.9.88\drivers\usb\chipidea\ci_hdrc_imx.c`
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```c
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ci_hdrc_imx_probe
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ci_hdrc_add_device
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pdev = platform_device_alloc("ci_hdrc", id);
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// Linux-4.9.88\drivers\usb\chipidea\core.c
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static struct platform_driver ci_hdrc_driver = {
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.probe = ci_hdrc_probe,
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.remove = ci_hdrc_remove,
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.driver = {
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.name = "ci_hdrc",
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.pm = &ci_pm_ops,
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},
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};
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ci_hdrc_probe
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ret = ci_hdrc_gadget_init(ci);
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udc_start
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```
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### 1.2 UDC驱动分析
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```shell
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/home/book/100ask_imx6ull-sdk/Linux-4.9.88/drivers/usb/chipidea/ci_hdrc_imx.c
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data->ci_pdev = ci_hdrc_add_device(dev,
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pdev->resource, pdev->num_resources,
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&pdata);
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/home/book/100ask_imx6ull-sdk/Linux-4.9.88/drivers/usb/chipidea/core.c
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static struct platform_driver ci_hdrc_driver = {
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.probe = ci_hdrc_probe,
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.remove = ci_hdrc_remove,
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.driver = {
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.name = "ci_hdrc",
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.pm = &ci_pm_ops,
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},
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};
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```
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* STM32MP157的代码：`Linux-5.4\drivers\usb\dwc2\platform.c`
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```c
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dwc2_driver_probe
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retval = dwc2_gadget_init(hsotg);
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```
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中断：
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## 3. 从描述符的角度理解Gadget框架
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假设你要模拟一个USB串口芯片，
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* 这个USB串口芯片含有厂家信息：它记录在设备描述符里，所以设备描述符应该由你提供
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* 这个芯片可能有多种配置，这也是由你决定，所以配置描述符应该由你提供
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* 某个配置下多个接口，接口就是功能，Linux内核里事先提供了很多功能的驱动程序，所以：接口描述符是内核提供的
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* 某个接口下需要什么端点，也是内核提供的，所以：端点描述符是内核提供的
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以zero.c为例，从下到上涉及这些文件：
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#### 1.2.1 注册udc
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```c
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// drivers/usb/chipidea/core.c
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ci_hdrc_probe
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ret = ci_hdrc_gadget_init(ci);
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struct ci_role_driver *rdrv;
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rdrv->start = udc_id_switch_for_device;
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rdrv->stop = udc_id_switch_for_host;
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rdrv->irq = udc_irq;
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rdrv->suspend = udc_suspend;
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rdrv->resume = udc_resume;
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rdrv->name = "gadget";
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ret = udc_start(ci);
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ci->gadget.ops = &usb_gadget_ops;
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ci->gadget.speed = USB_SPEED_UNKNOWN;
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ci->gadget.max_speed = USB_SPEED_HIGH;
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ci->gadget.name = ci->platdata->name;
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ci->gadget.otg_caps = otg_caps;
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retval = init_eps(ci);
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hwep->ep.name = hwep->name;
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hwep->ep.ops = &usb_ep_ops;
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if (retval)
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goto free_pools;
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ci->gadget.ep0 = &ci->ep0in->ep;
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## 4. 从获得描述符的角度理解Gadget框架
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## 5. 从数据传输的角度理解Gadget框架
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retval = usb_add_gadget_udc(dev, &ci->gadget);
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usb_add_gadget_udc_release(parent, gadget, NULL);
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list_add_tail(&udc->list, &udc_list);
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if (!ret)
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ci->roles[CI_ROLE_GADGET] = rdrv;
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platform_set_drvdata(pdev, ci);
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ret = devm_request_irq(dev, ci->irq, ci_irq, IRQF_SHARED,
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ci->platdata->name, ci);
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if (ret)
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goto stop;
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```
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#### 1.2.2 UDC中断处理函数
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```c
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// /home/book/100ask_imx6ull-sdk/Linux-4.9.88/drivers/usb/chipidea/core.c
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ci_irq
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/* Handle device/host interrupt */
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if (ci->role != CI_ROLE_END)
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ret = ci_role(ci)->irq(ci);
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udc_irq
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if (USBi_UI & intr)
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isr_tr_complete_handler(ci);
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/* Only handle setup packet below */
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if (i == 0 &&
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hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
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isr_setup_packet_handler(ci);
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```
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#### 1.2.3 控制传输的处理
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isr_setup_packet_handler对于ep0的处理，
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有很多x消息并不需要传递到最上层的composite驱动，
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这个函数的前面代码就自己处理了这些setup包，
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后面无法处理的request才交给上层
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```c
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static void isr_setup_packet_handler(struct ci_hdrc *ci)
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__releases(ci->lock)
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__acquires(ci->lock)
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{
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struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
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struct usb_ctrlrequest req;
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int type, num, dir, err = -EINVAL;
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u8 tmode = 0;
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/*
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* Flush data and handshake transactions of previous
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* setup packet.
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*/
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_ep_nuke(ci->ep0out);
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_ep_nuke(ci->ep0in);
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/* read_setup_packet */
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do {
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hw_test_and_set_setup_guard(ci);
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memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
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} while (!hw_test_and_clear_setup_guard(ci));
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type = req.bRequestType;
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ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
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switch (req.bRequest) {
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case USB_REQ_CLEAR_FEATURE:
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if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
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le16_to_cpu(req.wValue) ==
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USB_ENDPOINT_HALT) {
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if (req.wLength != 0)
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break;
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num = le16_to_cpu(req.wIndex);
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dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
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num &= USB_ENDPOINT_NUMBER_MASK;
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if (dir == TX)
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num += ci->hw_ep_max / 2;
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if (!ci->ci_hw_ep[num].wedge) {
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spin_unlock(&ci->lock);
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err = usb_ep_clear_halt(
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&ci->ci_hw_ep[num].ep);
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spin_lock(&ci->lock);
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if (err)
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break;
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}
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err = isr_setup_status_phase(ci);
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} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
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le16_to_cpu(req.wValue) ==
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USB_DEVICE_REMOTE_WAKEUP) {
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if (req.wLength != 0)
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break;
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ci->remote_wakeup = 0;
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err = isr_setup_status_phase(ci);
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} else {
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goto delegate;
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}
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break;
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case USB_REQ_GET_STATUS:
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if ((type != (USB_DIR_IN|USB_RECIP_DEVICE) ||
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le16_to_cpu(req.wIndex) == OTG_STS_SELECTOR) &&
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type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
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type != (USB_DIR_IN|USB_RECIP_INTERFACE))
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goto delegate;
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if ((le16_to_cpu(req.wLength) != 2 &&
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le16_to_cpu(req.wLength) != 1) ||
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le16_to_cpu(req.wValue) != 0)
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break;
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err = isr_get_status_response(ci, &req);
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break;
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case USB_REQ_SET_ADDRESS:
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if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
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goto delegate;
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if (le16_to_cpu(req.wLength) != 0 ||
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le16_to_cpu(req.wIndex) != 0)
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break;
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ci->address = (u8)le16_to_cpu(req.wValue);
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ci->setaddr = true;
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err = isr_setup_status_phase(ci);
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break;
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case USB_REQ_SET_FEATURE:
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if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
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le16_to_cpu(req.wValue) ==
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USB_ENDPOINT_HALT) {
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if (req.wLength != 0)
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break;
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num = le16_to_cpu(req.wIndex);
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dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
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num &= USB_ENDPOINT_NUMBER_MASK;
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if (dir == TX)
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num += ci->hw_ep_max / 2;
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spin_unlock(&ci->lock);
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err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
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spin_lock(&ci->lock);
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if (!err)
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isr_setup_status_phase(ci);
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} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
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if (req.wLength != 0)
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break;
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||||
switch (le16_to_cpu(req.wValue)) {
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case USB_DEVICE_REMOTE_WAKEUP:
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ci->remote_wakeup = 1;
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err = isr_setup_status_phase(ci);
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break;
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||||
case USB_DEVICE_TEST_MODE:
|
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tmode = le16_to_cpu(req.wIndex) >> 8;
|
||||
switch (tmode) {
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case TEST_J:
|
||||
case TEST_K:
|
||||
case TEST_SE0_NAK:
|
||||
case TEST_PACKET:
|
||||
case TEST_FORCE_EN:
|
||||
ci->test_mode = tmode;
|
||||
err = isr_setup_status_phase(
|
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ci);
|
||||
break;
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||||
case TEST_OTG_SRP_REQD:
|
||||
err = otg_srp_reqd(ci);
|
||||
break;
|
||||
case TEST_OTG_HNP_REQD:
|
||||
err = otg_hnp_reqd(ci);
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
break;
|
||||
case USB_DEVICE_B_HNP_ENABLE:
|
||||
if (ci_otg_is_fsm_mode(ci)) {
|
||||
ci->gadget.b_hnp_enable = 1;
|
||||
err = isr_setup_status_phase(
|
||||
ci);
|
||||
}
|
||||
break;
|
||||
case USB_DEVICE_A_ALT_HNP_SUPPORT:
|
||||
if (ci_otg_is_fsm_mode(ci))
|
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err = otg_a_alt_hnp_support(ci);
|
||||
break;
|
||||
case USB_DEVICE_A_HNP_SUPPORT:
|
||||
if (ci_otg_is_fsm_mode(ci)) {
|
||||
ci->gadget.a_hnp_support = 1;
|
||||
err = isr_setup_status_phase(
|
||||
ci);
|
||||
}
|
||||
break;
|
||||
default:
|
||||
goto delegate;
|
||||
}
|
||||
} else {
|
||||
goto delegate;
|
||||
}
|
||||
break;
|
||||
default:
|
||||
delegate:
|
||||
if (req.wLength == 0) /* no data phase */
|
||||
ci->ep0_dir = TX;
|
||||
|
||||
spin_unlock(&ci->lock);
|
||||
err = ci->driver->setup(&ci->gadget, &req);
|
||||
// composite_driver_template.setup
|
||||
composite_setup
|
||||
spin_lock(&ci->lock);
|
||||
break;
|
||||
}
|
||||
|
||||
if (err < 0) {
|
||||
spin_unlock(&ci->lock);
|
||||
if (_ep_set_halt(&hwep->ep, 1, false))
|
||||
dev_err(ci->dev, "error: _ep_set_halt\n");
|
||||
spin_lock(&ci->lock);
|
||||
}
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
#### 1.2.4 EP什么时候使能
|
||||
|
||||
```c
|
||||
static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
|
||||
{
|
||||
int ret;
|
||||
|
||||
dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
|
||||
driver->function);
|
||||
|
||||
udc->driver = driver;
|
||||
udc->dev.driver = &driver->driver;
|
||||
udc->gadget->dev.driver = &driver->driver;
|
||||
|
||||
ret = driver->bind(udc->gadget, driver);
|
||||
if (ret)
|
||||
goto err1;
|
||||
ret = usb_gadget_udc_start(udc);
|
||||
return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
|
||||
ci_udc_start
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
BIN
IMX6ULL/doc_pic/12_USB/pic/82_usb_ep_ops.png
Normal file
BIN
IMX6ULL/doc_pic/12_USB/pic/82_usb_ep_ops.png
Normal file
Binary file not shown.
|
After Width: | Height: | Size: 36 KiB |
BIN
IMX6ULL/doc_pic/12_USB/pic/83_soft_hard.png
Normal file
BIN
IMX6ULL/doc_pic/12_USB/pic/83_soft_hard.png
Normal file
Binary file not shown.
|
After Width: | Height: | Size: 257 KiB |
BIN
IMX6ULL/doc_pic/12_USB/pic/84_imx6ull_udc.png
Normal file
BIN
IMX6ULL/doc_pic/12_USB/pic/84_imx6ull_udc.png
Normal file
Binary file not shown.
|
After Width: | Height: | Size: 93 KiB |
BIN
IMX6ULL/doc_pic/12_USB/pic/85_stm32mp157_udc.png
Normal file
BIN
IMX6ULL/doc_pic/12_USB/pic/85_stm32mp157_udc.png
Normal file
Binary file not shown.
|
After Width: | Height: | Size: 183 KiB |
BIN
IMX6ULL/doc_pic/12_USB/pic/86_host_device.png
Normal file
BIN
IMX6ULL/doc_pic/12_USB/pic/86_host_device.png
Normal file
Binary file not shown.
|
After Width: | Height: | Size: 11 KiB |
404
IMX6ULL/doc_pic/12_USB/tmp.md
Normal file
404
IMX6ULL/doc_pic/12_USB/tmp.md
Normal file
@@ -0,0 +1,404 @@
|
||||
# Gadget驱动程序框架 #
|
||||
|
||||
参考资料：
|
||||
|
||||
* Linux下USB gadget设备详解：https://www.docin.com/p-1852320293.html
|
||||
* Linux usb gadget框架概述：https://blog.csdn.net/daocaokafei/article/details/114114824
|
||||
* USB设备驱动程序-USB Gadget Driver(二)：https://blog.csdn.net/chenzhen1080/article/details/53742924
|
||||
* usb gadge驱动设计之我是zero：https://www.bbsmax.com/A/Ae5RvbwM5Q/
|
||||
* Linux-USB驱动笔记（四）--USB整体框架: https://qingmu.blog.csdn.net/article/details/119979199
|
||||
* USB gadget设备驱动解析: https://www.likecs.com/show-843861.html
|
||||
* 调试软件：USB view 、bushound 、及一些硬件USB信号分析仪
|
||||
* 可以用[wireshark](https://so.csdn.net/so/search?q=wireshark&spm=1001.2101.3001.7020)+usbmon捕捉usb协议数据包。
|
||||
|
||||
|
||||
|
||||
## 1. 笔记
|
||||
|
||||
Tutorial about USB HID Report Descriptors
|
||||
|
||||
https://eleccelerator.com/tutorial-about-usb-hid-report-descriptors/
|
||||
|
||||
USB HID Report Descriptor 报告描述符详解 - Climber丶 - 博客园.html
|
||||
|
||||
https://www.cnblogs.com/AlwaysOnLines/p/3859557.html
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
```shell
|
||||
struct usb_gadget - represents a usb slave device
|
||||
struct usb_composite_device - represents one composite usb gadget
|
||||
struct usb_udc - describes one usb device controller
|
||||
```
|
||||
|
||||
|
||||
|
||||
```c
|
||||
/**
|
||||
* struct usb_udc - describes one usb device controller
|
||||
* @driver - the gadget driver pointer. For use by the class code
|
||||
* @dev - the child device to the actual controller
|
||||
* @gadget - the gadget. For use by the class code
|
||||
* @list - for use by the udc class driver
|
||||
* @vbus - for udcs who care about vbus status, this value is real vbus status;
|
||||
* for udcs who do not care about vbus status, this value is always true
|
||||
*
|
||||
* This represents the internal data structure which is used by the UDC-class
|
||||
* to hold information about udc driver and gadget together.
|
||||
*/
|
||||
struct usb_udc {
|
||||
struct usb_gadget_driver *driver;
|
||||
struct usb_gadget *gadget;
|
||||
struct device dev;
|
||||
struct list_head list;
|
||||
bool vbus;
|
||||
};
|
||||
|
||||
|
||||
// usb_udc用来表示USB设备控制器，它里面有：
|
||||
// 1. usb_gadget : 用来表示硬件信息？represents a usb slave device，比如USB串口？
|
||||
// 2. usb_gadget_driver: 用来表示软件信息？driver for usb 'slave' devices
|
||||
```
|
||||
|
||||
|
||||
|
||||
usb_gadget和usb_composite_dev必定一起出现：usb_gadget描述的是硬件底层信息(?)，usb_composite_dev描述的是硬件的上层信息(？)
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
### 1.1 结构体
|
||||
|
||||
```c
|
||||
struct usb_udc - describes one usb device controller
|
||||
struct usb_gadget - represents a usb slave device
|
||||
struct usb_gadget_driver - driver for usb 'slave' devices
|
||||
struct usb_composite_device - represents one composite usb gadget
|
||||
struct usb_function - describes one function of a configuration
|
||||
struct usb_composite_driver - groups configurations into a gadget
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
### 1.2 UDC驱动分析
|
||||
|
||||
```shell
|
||||
/home/book/100ask_imx6ull-sdk/Linux-4.9.88/drivers/usb/chipidea/ci_hdrc_imx.c
|
||||
data->ci_pdev = ci_hdrc_add_device(dev,
|
||||
pdev->resource, pdev->num_resources,
|
||||
&pdata);
|
||||
|
||||
/home/book/100ask_imx6ull-sdk/Linux-4.9.88/drivers/usb/chipidea/core.c
|
||||
static struct platform_driver ci_hdrc_driver = {
|
||||
.probe = ci_hdrc_probe,
|
||||
.remove = ci_hdrc_remove,
|
||||
.driver = {
|
||||
.name = "ci_hdrc",
|
||||
.pm = &ci_pm_ops,
|
||||
},
|
||||
};
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
中断：
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
#### 1.2.1 注册udc
|
||||
|
||||
```c
|
||||
// drivers/usb/chipidea/core.c
|
||||
ci_hdrc_probe
|
||||
ret = ci_hdrc_gadget_init(ci);
|
||||
struct ci_role_driver *rdrv;
|
||||
rdrv->start = udc_id_switch_for_device;
|
||||
rdrv->stop = udc_id_switch_for_host;
|
||||
rdrv->irq = udc_irq;
|
||||
rdrv->suspend = udc_suspend;
|
||||
rdrv->resume = udc_resume;
|
||||
rdrv->name = "gadget";
|
||||
|
||||
ret = udc_start(ci);
|
||||
ci->gadget.ops = &usb_gadget_ops;
|
||||
ci->gadget.speed = USB_SPEED_UNKNOWN;
|
||||
ci->gadget.max_speed = USB_SPEED_HIGH;
|
||||
ci->gadget.name = ci->platdata->name;
|
||||
ci->gadget.otg_caps = otg_caps;
|
||||
|
||||
retval = init_eps(ci);
|
||||
hwep->ep.name = hwep->name;
|
||||
hwep->ep.ops = &usb_ep_ops;
|
||||
if (retval)
|
||||
goto free_pools;
|
||||
|
||||
ci->gadget.ep0 = &ci->ep0in->ep;
|
||||
|
||||
retval = usb_add_gadget_udc(dev, &ci->gadget);
|
||||
usb_add_gadget_udc_release(parent, gadget, NULL);
|
||||
list_add_tail(&udc->list, &udc_list);
|
||||
if (!ret)
|
||||
ci->roles[CI_ROLE_GADGET] = rdrv;
|
||||
|
||||
platform_set_drvdata(pdev, ci);
|
||||
ret = devm_request_irq(dev, ci->irq, ci_irq, IRQF_SHARED,
|
||||
ci->platdata->name, ci);
|
||||
if (ret)
|
||||
goto stop;
|
||||
```
|
||||
|
||||
|
||||
|
||||
#### 1.2.2 UDC中断处理函数
|
||||
|
||||
```c
|
||||
// /home/book/100ask_imx6ull-sdk/Linux-4.9.88/drivers/usb/chipidea/core.c
|
||||
ci_irq
|
||||
/* Handle device/host interrupt */
|
||||
if (ci->role != CI_ROLE_END)
|
||||
ret = ci_role(ci)->irq(ci);
|
||||
udc_irq
|
||||
if (USBi_UI & intr)
|
||||
isr_tr_complete_handler(ci);
|
||||
|
||||
/* Only handle setup packet below */
|
||||
if (i == 0 &&
|
||||
hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
|
||||
isr_setup_packet_handler(ci);
|
||||
```
|
||||
|
||||
|
||||
|
||||
#### 1.2.3 控制传输的处理
|
||||
|
||||
isr_setup_packet_handler对于ep0的处理，
|
||||
|
||||
有很多x消息并不需要传递到最上层的composite驱动，
|
||||
|
||||
这个函数的前面代码就自己处理了这些setup包，
|
||||
|
||||
后面无法处理的request才交给上层
|
||||
|
||||
```c
|
||||
static void isr_setup_packet_handler(struct ci_hdrc *ci)
|
||||
__releases(ci->lock)
|
||||
__acquires(ci->lock)
|
||||
{
|
||||
struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
|
||||
struct usb_ctrlrequest req;
|
||||
int type, num, dir, err = -EINVAL;
|
||||
u8 tmode = 0;
|
||||
|
||||
/*
|
||||
* Flush data and handshake transactions of previous
|
||||
* setup packet.
|
||||
*/
|
||||
_ep_nuke(ci->ep0out);
|
||||
_ep_nuke(ci->ep0in);
|
||||
|
||||
/* read_setup_packet */
|
||||
do {
|
||||
hw_test_and_set_setup_guard(ci);
|
||||
memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
|
||||
} while (!hw_test_and_clear_setup_guard(ci));
|
||||
|
||||
type = req.bRequestType;
|
||||
|
||||
ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
|
||||
|
||||
switch (req.bRequest) {
|
||||
case USB_REQ_CLEAR_FEATURE:
|
||||
if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
|
||||
le16_to_cpu(req.wValue) ==
|
||||
USB_ENDPOINT_HALT) {
|
||||
if (req.wLength != 0)
|
||||
break;
|
||||
num = le16_to_cpu(req.wIndex);
|
||||
dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
|
||||
num &= USB_ENDPOINT_NUMBER_MASK;
|
||||
if (dir == TX)
|
||||
num += ci->hw_ep_max / 2;
|
||||
if (!ci->ci_hw_ep[num].wedge) {
|
||||
spin_unlock(&ci->lock);
|
||||
err = usb_ep_clear_halt(
|
||||
&ci->ci_hw_ep[num].ep);
|
||||
spin_lock(&ci->lock);
|
||||
if (err)
|
||||
break;
|
||||
}
|
||||
err = isr_setup_status_phase(ci);
|
||||
} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
|
||||
le16_to_cpu(req.wValue) ==
|
||||
USB_DEVICE_REMOTE_WAKEUP) {
|
||||
if (req.wLength != 0)
|
||||
break;
|
||||
ci->remote_wakeup = 0;
|
||||
err = isr_setup_status_phase(ci);
|
||||
} else {
|
||||
goto delegate;
|
||||
}
|
||||
break;
|
||||
case USB_REQ_GET_STATUS:
|
||||
if ((type != (USB_DIR_IN|USB_RECIP_DEVICE) ||
|
||||
le16_to_cpu(req.wIndex) == OTG_STS_SELECTOR) &&
|
||||
type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
|
||||
type != (USB_DIR_IN|USB_RECIP_INTERFACE))
|
||||
goto delegate;
|
||||
if ((le16_to_cpu(req.wLength) != 2 &&
|
||||
le16_to_cpu(req.wLength) != 1) ||
|
||||
le16_to_cpu(req.wValue) != 0)
|
||||
break;
|
||||
err = isr_get_status_response(ci, &req);
|
||||
break;
|
||||
case USB_REQ_SET_ADDRESS:
|
||||
if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
|
||||
goto delegate;
|
||||
if (le16_to_cpu(req.wLength) != 0 ||
|
||||
le16_to_cpu(req.wIndex) != 0)
|
||||
break;
|
||||
ci->address = (u8)le16_to_cpu(req.wValue);
|
||||
ci->setaddr = true;
|
||||
err = isr_setup_status_phase(ci);
|
||||
break;
|
||||
case USB_REQ_SET_FEATURE:
|
||||
if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
|
||||
le16_to_cpu(req.wValue) ==
|
||||
USB_ENDPOINT_HALT) {
|
||||
if (req.wLength != 0)
|
||||
break;
|
||||
num = le16_to_cpu(req.wIndex);
|
||||
dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
|
||||
num &= USB_ENDPOINT_NUMBER_MASK;
|
||||
if (dir == TX)
|
||||
num += ci->hw_ep_max / 2;
|
||||
|
||||
spin_unlock(&ci->lock);
|
||||
err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
|
||||
spin_lock(&ci->lock);
|
||||
if (!err)
|
||||
isr_setup_status_phase(ci);
|
||||
} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
|
||||
if (req.wLength != 0)
|
||||
break;
|
||||
switch (le16_to_cpu(req.wValue)) {
|
||||
case USB_DEVICE_REMOTE_WAKEUP:
|
||||
ci->remote_wakeup = 1;
|
||||
err = isr_setup_status_phase(ci);
|
||||
break;
|
||||
case USB_DEVICE_TEST_MODE:
|
||||
tmode = le16_to_cpu(req.wIndex) >> 8;
|
||||
switch (tmode) {
|
||||
case TEST_J:
|
||||
case TEST_K:
|
||||
case TEST_SE0_NAK:
|
||||
case TEST_PACKET:
|
||||
case TEST_FORCE_EN:
|
||||
ci->test_mode = tmode;
|
||||
err = isr_setup_status_phase(
|
||||
ci);
|
||||
break;
|
||||
case TEST_OTG_SRP_REQD:
|
||||
err = otg_srp_reqd(ci);
|
||||
break;
|
||||
case TEST_OTG_HNP_REQD:
|
||||
err = otg_hnp_reqd(ci);
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
break;
|
||||
case USB_DEVICE_B_HNP_ENABLE:
|
||||
if (ci_otg_is_fsm_mode(ci)) {
|
||||
ci->gadget.b_hnp_enable = 1;
|
||||
err = isr_setup_status_phase(
|
||||
ci);
|
||||
}
|
||||
break;
|
||||
case USB_DEVICE_A_ALT_HNP_SUPPORT:
|
||||
if (ci_otg_is_fsm_mode(ci))
|
||||
err = otg_a_alt_hnp_support(ci);
|
||||
break;
|
||||
case USB_DEVICE_A_HNP_SUPPORT:
|
||||
if (ci_otg_is_fsm_mode(ci)) {
|
||||
ci->gadget.a_hnp_support = 1;
|
||||
err = isr_setup_status_phase(
|
||||
ci);
|
||||
}
|
||||
break;
|
||||
default:
|
||||
goto delegate;
|
||||
}
|
||||
} else {
|
||||
goto delegate;
|
||||
}
|
||||
break;
|
||||
default:
|
||||
delegate:
|
||||
if (req.wLength == 0) /* no data phase */
|
||||
ci->ep0_dir = TX;
|
||||
|
||||
spin_unlock(&ci->lock);
|
||||
err = ci->driver->setup(&ci->gadget, &req);
|
||||
// composite_driver_template.setup
|
||||
composite_setup
|
||||
spin_lock(&ci->lock);
|
||||
break;
|
||||
}
|
||||
|
||||
if (err < 0) {
|
||||
spin_unlock(&ci->lock);
|
||||
if (_ep_set_halt(&hwep->ep, 1, false))
|
||||
dev_err(ci->dev, "error: _ep_set_halt\n");
|
||||
spin_lock(&ci->lock);
|
||||
}
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
#### 1.2.4 EP什么时候使能
|
||||
|
||||
```c
|
||||
static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
|
||||
{
|
||||
int ret;
|
||||
|
||||
dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
|
||||
driver->function);
|
||||
|
||||
udc->driver = driver;
|
||||
udc->dev.driver = &driver->driver;
|
||||
udc->gadget->dev.driver = &driver->driver;
|
||||
|
||||
ret = driver->bind(udc->gadget, driver);
|
||||
if (ret)
|
||||
goto err1;
|
||||
ret = usb_gadget_udc_start(udc);
|
||||
return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
|
||||
ci_udc_start
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
##
|
||||
95216
IMX6ULL/doc_pic/12_USB/usb_20_20211008/hut1_3_0.pdf
Normal file
95216
IMX6ULL/doc_pic/12_USB/usb_20_20211008/hut1_3_0.pdf
Normal file
File diff suppressed because it is too large
Load Diff
Reference in New Issue
Block a user