A device driver or software driver is a computer program allowing higher-level computer programs to interact with a hardware device.

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What's the philosophy behind delaying writing data to disk?

In Linux, a finished execution of a command such as cp or dd doesn't mean that the data has been written to the device. One has to, for example, call sync, or invoke the "Safely Remove" or "Eject" ...
40
votes
4answers
37k views

Moving linux install to a new computer

I know that it can, in some circumstances, be difficult to move a Windows installation from one computer to another (physically move the hard drive), but how does that work on linux? Aren't most of ...
39
votes
3answers
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Does the kernel have a main() function? [closed]

I am learning device drivers and Kernel programming. According to Jonathan Corbet's book, there is no main() function in device drivers. So I two questions: Why don't we need a main() function in ...
39
votes
5answers
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What is the difference between kernel drivers and kernel modules?

When I do a lspci -k on my Kubuntu with a 3.2.0-29-generic kernel I can see something like this: 01:00.0 VGA compatible controller: NVIDIA Corporation G86 [Quadro NVS 290] (rev a1) Subsystem: ...
34
votes
2answers
30k views

What is difference between User space and Kernel space?

Is Kernel space used when Kernel is executing on the behalf of the user program i.e. System Call? Or is it the address space for all the Kernel threads (for example scheduler)? If it is the first one,...
28
votes
4answers
15k views

How to find the driver (module) associated with a device on Linux?

On Linux, given: a device, for example /dev/sda, and its major and minor numbers, for example 8, 0, how can I know which module / driver is "driving" it? Can I dig into /sys or /proc to ...
24
votes
2answers
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What is the difference between ioctl(), unlocked_ioctl() and compat_ioctl()?

Going through the linux 2.6.36 source code at lxr.linux.no, I could not find the ioctl() method in file_operations. Instead I found two new calls: unlocked_ioctl() and compat_ioctl(). What is the ...
22
votes
1answer
23k views

How to assign USB driver to device

This question is two-fold: First, how do you manually detach a driver from a USB device and attach a different one? For example, I have a device that when connected automatically uses the usb-...
21
votes
1answer
534 views

How to get started writing drivers?

I have a throw-away cheap laptop I'd like to twiddle around, a Thinkpad SL 500. What bothers me are two leds, the one for wireless connectivity, and the one for hibernation, which don't light up at ...
20
votes
1answer
21k views

How to use Linux kernel driver bind/unbind interface for USB-HID devices?

First background. I am developing a driver for Logitech game-panel devices. It's a keyboard with a screen on it. The driver is working nicely but by default the device is handled by HID. In order to ...
18
votes
3answers
16k views

Find out which modules are associated with a usb device?

Could you recommend a way to figure out which driver is being used for a USB device. Sort of a usb equivalent of lspci -k command.
17
votes
1answer
631 views

How is new hardware support added to the linux kernel?

Imagine there's a company A that releases a new graphics adapter. Who manages the process that results in this new graphics adapter being supported by the Linux kernel in the future? How does that ...
16
votes
3answers
5k views

Why don't you need to update drivers? (Or do you?)

In my life I've not once updated drivers on any of my Linux systems, though they have all been desktops. A friend was asking me why one does not need to update Linux drivers and I found myself unable ...
15
votes
1answer
13k views

How to setup GParted video mode in Oracle Virtualbox?

I'm trying to boot GParted live 0.14.1-6 within Oracle Virtualbox 4.2.6 r82870 (Extension Pack installed). The host OS is Windows 7, the physical graphic card is an AMD Radeon HD 6900. The physical ...
15
votes
2answers
2k views

Which NVIDIA driver should I use?

I have an NVIDIA GeForce 9500 GT. I'm currently using nvidia-331 since the Nouveau open drivers were giving me some trouble. But I have several other drivers to select, see: What are the ...
15
votes
3answers
5k views

Is USB-to-USB data transfer between two Linux OSes possible?

I want to create a USB-to-USB data transfer system in Linux (preferably Ubuntu). For this I want to use no external hardware or switch (except this cable). It's going to be like mounting a USB drive ...
12
votes
2answers
34k views

How to find out which Wi-Fi driver is installed?

I know about lsmod, but how do I figure out which driver does what?
12
votes
2answers
3k views

What’s the difference between a “raw” and a “cooked” device driver?

Does this concept only apply to terminal drivers (which is what most sites cover) or to any driver in general?
12
votes
2answers
16k views

How to debug the input from an input-device (/dev/input/event*)

I have a IR reciver that is using the imon-driver and i would like to get it working with the kernel. Right now half of the keys on the remote (image) works, but an all important think like the ...
12
votes
2answers
2k views

Using many monitors (4+) in linux

I want to be able to run more than 4 monitors (maybe 6) and it's extremely confusing what's compatible now with the Displayport cards coming out. Right now I have an ATI card that only has 2 HDMI ...
10
votes
3answers
2k views

Should I restart after a pacman upgrade?

after running sudo pacman -Syyu or sudo pacman -S [something to install] should I restart just to be safe?
10
votes
1answer
2k views

What driver is behind a certain device file?

Given a device file, say /dev/sdb, is it possible to determine what driver is behind it? Specifically, I want to determine what driver my storage devices are using. fdisk -l lists 2 devices: /dev/sda ...
10
votes
2answers
7k views

Attaching USB-Serial device with custom PID to ttyUSB0 on embedded

I'm attempting to get an FTDI USB-Serial device with a custom PID to automatically (or even manually) attach to ttyUSB%n, without much success. The device's normal VID/PID is 0403/6001. When ...
10
votes
3answers
9k views

Microphone - static background noise suppression on Linux

My soundcard is Realtek ALC 892. On Windows 7 I use official Realtek drivers, on Linux I use PulseAudio (on Ubuntu 13.10). On both Windows and Linux, when I enable microphone boost +30db (required ...
10
votes
4answers
5k views

wireless is disabled by hardware switch even when not

I have a spartan computer. It has a built-in wireless module that up until recently I've had no issues with. The current problem is this. Everytime I shutdown the computer and it boots back up, I am ...
10
votes
1answer
798 views

Driver is sometimes loaded, sometimes not

I was assigned an Ubuntu desktop with some stuff already on it. I did not reformat it, but attached a mini-PCI wireless card over a PCI to mini-PCI adapter. I manually built the madwifi driver and ...
9
votes
3answers
8k views

Error compiling drivers for Ralink RT2870

Im trying to install drivers for a rosewill RNX-N600UBE wireless card (Ralink RT2870 chipset) on Kali Linux. I downloaded the drivers form their website and unpacked/unzipped them, but now when i try ...
9
votes
1answer
764 views

Why need drivers for both x server and the linux kernel?

Can someone explain why two sets of drivers are needed, one in the Linux kernel and one in X? I understand that the device drivers are in the kernel, but what is the role of those in the xserver? ...
9
votes
3answers
9k views

Understanding character device (or character special) files

I am trying to understand character special files. From wikipedia, I understand that these files "provide an interface" for devices that transmit data one character at a time. My understanding is ...
9
votes
2answers
12k views

How to find out which X11 driver system is using?

How to find out which X11 driver system is using? For my chip openchrome is the best driver but I suspect that system is not using it. I just need at least 2D acceleration. How can I check? Here is ...
8
votes
3answers
15k views

mptscsih: ioc0: task abort: SUCCESS (rv=2002) causes 30 seconds freezing

I/O to my software RAID6 often freezes for around 30 seconds after which everything is back to normal. After the freeze is over this is put into syslog: Mar 14 18:43:57 server kernel: [35649.816060] ...
8
votes
2answers
431 views

Connect alauda driver to an mtd device

I have a USB card reader, an Olympus MAUSB-10. It provides direct flash access to SmartMedia or xD cards, using the Linux alauda driver. This is different from a typical card reader which just ...
7
votes
2answers
948 views

What decides which kernel modules are built in the kernel statically during compilation?

I just compiled a new kernel and asked myself: What decides during the compilation process which kernel modules are built in the kernel statically? I then deleted /lib/modules, rebooted and found ...
7
votes
2answers
95 views

How does linux driver update work?

As far as I know no update on a linux machine requires a restart. Windows however needs to restart several times for a update to complete which is understandable because the hardware might be in use ...
7
votes
3answers
2k views

How does libusb access kernel stuff?

From what I understand: Generally speaking, a driver runs in kernel space and can be called from user space. Only code in kernel space can call usb low level things / ioctl libusb is a library, so ...
7
votes
3answers
11k views

How can I tell if my wifi dongle has access-point capabilities?

I have a Realtek 8191SU USB wifi dongle for use on my Raspberry Pi. I'm trying to set up a wifi access point using this tutorial. However, I'm running into a few errors, and I suspect it might be ...
7
votes
1answer
4k views

Webcam on Angström

I am running Angström on my BeagleBoard-xm. I want to use a webcam (I have Microsoft LifeCam Cinema and Logitech C310). I installed v4l-utils, libv4l-dev and kernel-module-uvcvideo with opkg. But the ...
7
votes
2answers
8k views

How can I get xrandr to detect both nvidia cards: 2 x GTX480, triple-head?

I am running Linux Mint 16 (Petra) I am running the default driver nvidia-319 shipped with the distro I have 2x GTX480 cards I have 3 monitors Using the Nvidia driver, all monitors and GPUs are picked ...
7
votes
2answers
4k views

Enabling 1366x768 resolution in Debian Wheezy on Atom D525 Board

For some reason, when I try to update to a modern version of Linux from Debian 6.0.7 or Ubuntu 10.0.4, I lose most of the resolutions that were available, including the native resolution of the panel ...
7
votes
1answer
423 views

Installing USR 5422 on Ubuntu 12.04

I am a newbie to Linux. I was trying to set up the USR5422 USB adapter. It worked fine for the first time, but since then it freezes the computer most of the time. What commands can I fire to see ...
7
votes
1answer
458 views

Embedded linux LCD not calibrated

I have attached a new LCD to my embedded Linux device and when I run the system I found that it is shifted to the right. (the display starts from the middle of the LCD) I found 2 frame buffer drivers ...
7
votes
1answer
555 views

Why does a device show up as hidraw instead of hiddev?

I read the kernel documentation for hidraw and hiddev, and I understand the differences, but I am wondering how the kernel decides whether or not a device should show up as /dev/hidraw* or /dev/usb/...
6
votes
4answers
4k views

Best way to get into Kernel programming?

Not so much asking what books (although if you know of any guides/tutorials that'd be helpful) but what is the best way to start doing kernel programming and is there a particular distro that would be ...
6
votes
3answers
21k views

How do I display the name of my audio card driver from the command line in Lubuntu 11.10?

I am running Lubuntu 11.10 and I want to display my Audio / Sound Card Driver from the command line.
6
votes
2answers
5k views

Which device uses which driver under Linux?

How can I find out or list that what drivers the devices in my pc use?
6
votes
1answer
6k views

Which driver is handling my touchpad?

I would like to know how to determine which driver (out of those below) is handling my touchpad: appletouch.ko.gz, cyapa.ko.gz, sermouse.ko.gz, synaptics_usb.ko.gz, bcm5974.ko.gz, psmouse.ko.gz, ...
6
votes
4answers
251 views

Why are Linux installs bigger than I've read? Some beginner questions

I've read in different textbooks that say Linux is light-weight(e.g. It could fit on a 1.4MB floppy). So why is the download from the Ubuntu or Fedora CD sized or larger? Do the device drivers extend ...
6
votes
3answers
3k views

Implications of Linux support for AMD Fusion APUs?

As I understand it, the Linux kernel has had good support for Intel and AMD CPUs (pretty obvious since your OS installs and runs fine!). But now that AMD is releasing their new Fusion APUs, is it ...
6
votes
3answers
12k views

Prevent a USB external hard drive from sleeping

Does anyone know if there is an elegant way to tell an external usb drive not to spin down after a period of inactivity? I've seen cron based solutions that write a file every minute, but nothing ...
6
votes
2answers
4k views

Capturing key input from events device and mapping it (toggle TouchPad key is unmapped)

I have a Lenovo IdeaPad Yoga 13 with Ubuntu 13.10 Installed. The device has a "Toggle TouchPad" button on the keyboard (F5). The keyboard's F* buttons are reversed (so to get F5, I need to press Fn + ...