the kick_khubd function, add the current hub to the Hub driver queue hub_event_list, and then wake up the hub daemon wake_up (khubd_wait) to start parsing what happened to the hub.
3. After hub_thread is awakened, It will be executed and hub_events will also be executed.
4.
Execute PS-A | grep khubd on the terminal, and the khubd process is displayed. This is the hub daemon process. Our device is inserted into the USB interface (whether it is inserted with the hub, after the sub-hub), the daemon detects the issue and then notifies the master controller of the interruption. The master cont
Objective: To study USB in depth and take notes here. Welcome to the discussion.
[Linux 3.2] [Driver/USB/CORE/hub. C]
Function: usb_hub_init
int usb_hub_init(void){if (usb_register(hub_driver)
Usb_hub_init mainly implements two functions: one is to register the hub
, observe the brightness of the USB desk lamp. If you are accessing the device, in particular, when the USB desk lamp is connected to a mobile hard disk, the performance of the adapter is poor when the light fades or flashes. This is a potential threat for USB devices.
Step 3: View workmanship
For an excellent adapter, it must be well-developed internallyO
development.Windows driver according to the kind to divide, roughly divides into the bus drive, the function drive, the filter drives three kinds.USB is a hardware interface and must be disconnected from the lowest-level bus driver.The bus driver is responsible for managing all devices connected to a certain type of bus, such as a USB bus,It is responsible for m
After using the hub on ce, pay attention to the following points for the USB driver:1. Make sure that the buffer for transmission is large enough.2. If the USB sleep mode is set, make sure that the sleep mode is enabled during sleep.Modify the buffer:E: \ WINCE600 \ PLATFORM \ SMDK6410 \ src \ drivers \
After using the hub on ce, pay attention to the following points for the USB driver:
1. Make sure that the buffer for transmission is large enough.
2. If the USB sleep mode is set, make sure that the sleep mode is enabled during sleep.
Modify the buffer:
E: \ wince600 \ platform \ smdk6410 \ SRC \ drivers \
found that folder on my butt, right-click and waited for it to be thrown into the dumpster, but! The system also told me that there is no administrator rights, oh My computer I do not have administrative rights ... I am also drunk, and then I Baidu has an administrator authorized registry, finally have permission, so I decisively kicked it to the garbage box. As for the blue screen, OK, blue screens and that folder is not closed, because the cause of the blue screen I do not know why, so just s
Do countless years of computer engineers, incredibly today USB problems, it took me one hours to solve.
The problem is that the system is used, the USB mouse is gone, then the system blue screen, see is dump RAM. I was too lazy to wait and restarted the system.
Then, after the system restarts, the mouse is lost. I can't find it anymore.
Helpless, find PS2 mouse, point to open Device Manager, incredibly
recently, users of the Win7 system have found that when the machine is turned on, the bottom right corner of the desktop will jump out of the USB root hub prompt. Sometimes it even pops up Microsoft USB 2.0 host controller simulator has been safely removed, and if you open Device Manager you will find the Microsoft USB
", Irqnum); GotoErr_request_irq; } HCD-GT;IRQ =Irqnum; ...
...
} Here you see the call registration Interrupt function, and its interrupt handling callback function is USB_HCD_IRQ, which is also located under DRIVERS\USB\CORE\HCD.C Irqreturn_t USB_HCD_IRQ (intIrqvoid*__HCD) {
structUSB_HCD *HCD =__HCD; intStart = hcd->State ; if(unlikely (start = = Hc_state_halt | | !test_bit (hcd_flag_hw_accessible, hcd->flags))) returnIrq_none; if(HCD-GT;
increased reliability of hot-swappable parts, they can also be used as broken appliances, and because hot-swappable can be automatically restored, there are many hot-swappable chips to provide the system with the signal of line power, so that the system to do fault analysis, thus reducing the cost.Third, Linux under the USB hot-swap processing1, Linux under the USB hub
;//Descriptor Type _ _le16 wdata [1];
/* encoded with Utf-16le */ 2 USB Host Drive USB host controllers are available in 3 sizes: OHCI (Open Host controller Interface), UHCI (Universal hosts controller Interface) and EHCI (Enhanced host Co Ntroller Interface).2.1 Host Controller DriverIn the Linux kernel, the USB_HCD structure is used to describe the U
This article from the csdn blog, reproduced please indicate the source: http://blog.csdn.net/aaa6695798/archive/2009/11/06/4776202.aspx
All struct declarations can be found in the kernel source file USB. H. If you are interested, read the source code.
USB devices are actually complicated, but the Linux Kernel provides a subsystem called USB core to handle mos
. test and disconnect www.2cto.com In the struct usb_driver structure, there are two USB cores that are called when appropriate: (1) when the device is inserted, if the USB core thinks this driver can be processed (the USB core uses a list (a struct containing the manufacturer ID and device ID) to determine which
This article from Csdn Blog, reproduced please indicate the source: http://blog.csdn.net/aaa6695798/archive/2009/11/06/4776202.aspx
This part of all the structure of the Declaration can be found in the kernel source file usb.h, interested friends can read the source code.
USB devices are complex, but the Linux kernel provides a subsystem called USB core to handle most of the complex work, so this is wh
channel for communication between the high-level and USB devices. In addition, USB [) automatically manages the power of the USB device and allocates bandwidth. In the USB system, the HUB plays a key role in the normal operation of the
usb_device_id skel_table [] = {{Usb_device (usb_skel_vendor_id, usb_skel_product_id )},{}};Module_device_table (USB, skel_table );The first parameter of module_device_table is the device type. If it is a USB device, it is naturally USB (if it is a PCI device, it will be PCI, the two subsystems use the same macro to register the supported devices. This involves t
data, and the other two provide power for downstream devices. USB is a token-based bus. Similar to the token-based bus of a ring network or FDDI. The broadcast token of the USB master controller. the device on the bus checks whether the address in the token is consistent with itself and responds to the host by receiving or sending data. USB manages the
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