If the headset does not hear a sound:
We click on the computer in the lower right corner of the speaker button, right click on the playback device, in the playback option to set the headset as the default device and disable other devices.
If the microphone does not sound correctly, click the Speaker button in the lower-right corner of the computer, right-click on the recording device, check th
From: http://embed.chinaitlab.com/J2ME/877029.html
Recently, I was working on a Marvell project and encountered a hot plug-in problem. So I took a look at the relevant code. I would like to make a contribution here.
Here we take the PXA code as an example. The entire framework is simple and clear. The upper layers are headsetobserver. Java and hookswitchobserver. java,
They will directly read the state of a specific device in/sys/class/switch/, such as "/sys/class/switch/h2w/state" to obtain the
desktops, virtual cloud desktops and the like.Therefore, for virtual cloud Desktop developers, the solution of remote access to local devices is also one of the basic and important issues.Look at an example that is unfamiliar to the average person and familiar to iOS developers,iOS app installation problem, very annoying, unlike Windows programs, as long as the development, can be copied everywhere, run everywhere.Self-developed app, need to deploy the Xcode development environment to the mobil
host, only one device can communicate with the host at the same time. Manage the external USB device via the USB host controller. USB controller is actually composed of USB controller hardware +USB Controller software. The USB h
Because the USB driver in Linux is already very complete,You only need to follow the following configuration. After the configuration, recompile the kernel and install it on the Development Board.
1. Modify make menuconfig
System type -->
Input core support -->
SCSI device support --->
[*] Legacy/proc/SCSI/support
* ** SCSI support type (disk, tape, CD-ROM
urb_list; //URB for this endpoint, maintained by the USB core
void *hcpriv;
struct Ep_device *ep_dev; / * for SYSFS info * /
unsigned Char*extra; /* Extra descriptors * /
int Extralen;
int enabled;
};
an int usb_hcd_link_urb_to_ep (struct USB_HCD *hcd, struct URB *urb) is called to add this urb to urb_ when invoking the USB device driver call
Kernel 2.6.29.4 USB devices are actually complicated, but the Linux Kernel provides a subsystem called USB core to handle most of the complicated work. Therefore, the interface between the driver and USB core is described here.In the USB device organization structure, there
USB urb (USB request block)
Kernel 2.6.29.4The USB device driver code communicates with all USB devices through urb. Urb uses the struct urb structure description (include/Linux/USB. h ).
Urb sends or receives data asynchronously
Linux-USB Gadget
OverviewThe Linux-USB Gadget driver framework (hereinafter referred to as gadget) provides software functions for devices defined by the USB protocol.Compared with the Linux USB host driver, the gadget
, the serial number of the device, and so on. Its contents are given in Unicode and can be read by the client software. String descriptors are optional for USB devices.6. PipelineIn the structure of the USB system, it can be considered that the data transfer occurs directly between the USB host software and the various endpoints of the
Objective: To study USB in depth and take notes here. Welcome to the discussion.
[Linux 3.2] [Driver/USB/CORE/devio. C]
Definition: usbfs_driver
struct usb_driver usbfs_driver = {.name ="usbfs",.probe =driver_probe,.disconnect =driver_disconnect,.suspend =driver_suspend,.resume =driver_resume,};
[Linux 3.2] [INCLUDE/Linux/US
Http://www.linuxjournal.com/article/7466June 1st, 2004 by Greg kroah-Harman
In
Software
NowYou can control USB hardware without touching the kernel and even makeYour driver run on BSD-based OSes with no code changes. Greg showsWorking Example for using the cross-platform USB library, libusb.
Last time we discussed how to create a simple
From: http://hyt19860117.love.blog.163.com/blog/static/127773729201042435553852/
With the improvement of people's living standards, more and more USB devices are used, but Linux still does not fully Plug and Play in hardware configuration. how to configure and use Linux is alsoThis article is intended to help you understand how to develop a USB driver to facilita
To do USB-related things in wince, we must first understand some concepts, which is very important.
(1) host and FunctionFirst, you must know that the USB is a master-slave structure. For PCs and mobile phones, the PC end is the master end, called the host, and the mobile phone is the slave end, usually called the client. However, this term has changed in wince. The master end is also called host, while the
other half. On the contrary, whenever one structdevice_driver is born, it goes to the devices linked list of the bus to find its devices. If appropriate, call device_bind_driver to bind the device. If it cannot be found, it does not matter. wait.
In fact, perfecting this triangular relationship is one of the important missions completed in each device driver initialization phase. Let's go back to the code. the usb_register function is called, but wha
I. Linux USB driver levels
1. devices, configurations, interfaces, and endpointsThe logical organization of a USB device consists of four layers: device, configuration, interface, and endpoint.
A device usually has one or more configurations:
Each USB device provides different levels of configuration information,
Hardware driver in Linux system-USB device (on)
There are more and more USB devices, while Linux is still not completely plug-and-play in hardware configuration. how to configure and use Linux is becoming a major problem for us. This article describes how to use and configure the driver and how to compile the
With the increasing of USB devices, development of USB driver is becoming more and more important in embedded development. Windows CE's support for USB 2.0 is a huge boost to this wave of new technologies. The author of this article analyzes his own use-driven development experience, hoping that readers can take less d
Delphi sometimes cannot connect to debug some phones, solutions:1. Install Google USB Driver2. Check the phone or tablet USB vid,pid via Device Manager3. Modify the Android_winusb.inf on your computer to add the vid,pid found in the 2nd step to the INF.For example:; Samsung Galaxy S3%singleadbinterface% = usb_install, usb\vid_04e8pid_6860%compositeadbinterface% =
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