How to insert my driver automatically on the insertion of USB mouse in Linux System? - linux

Question

I know that on the insertion of any usb device in the Linux system a specific device driver got loaded. Now I want to insert my driver on the insertion of USB mouse.
I know that I can do this task using two approaches: by using depmod or using udev concept. I have read a few things about it on the Internet but I don't get the exact answer. Can anyone suggest which approach is best to use and for that in the Linux kernel tree where I need to make changes?

Answer 1

Thanks all for your help.
I follow the udev approach to load module automatically on the USB insertion
Below is the procedure to load your Driver automatically on the Insertion of Hot plug-gable device (I experiment with the USB mouse and below procedure is working fine for it)
Run Following command
cmd > udevadm info -a -p $(udevadm info -q path -n /dev/input/mouse)
In place of ?? in the above command user need to add the device ID based on its entry in /dev (e.g.for USB flash drive: sdb1 or sda1 etc. based on the device identity)
Get the Value of the below parameters from the output of above command
KERNEL, ATTRS{idVendor}, ATTRS{idProduct}, ATTRS{serial}
Go to /etc/dev/rule.d directory and Add your rule
cmd > sudo vim 40-usbmouse.rules
ACTION=="add", SUBSYSTEM=="block", KERNEL=="sd?1", ATTRS{idVendor}=="058f", ATTRS{idProduct}=="6387", ATTRS{serial} =="4EPLXAXE", SYMLINK+="usbpd", RUN+="/usr/local/bin/InsertModule.sh"
Save this file.
Above rule is defined for the USB Mouse.
Parameter SYMLINK creates a link of your device in the /dev directory and In RUN+ you can give your script location which is going to execute on your device insertion.
For more info on How to write a rule refer below link
http://hackaday.com/2009/09/18/how-to-write-udev-rules/
Now after you define your rule user need to restart the udev to take your rule in notice by kernel.
cmd > sudo stop udev
cmd > sudo start udev
Insert your USB and validate that your script which you define in your rule shows its effact.
For Mouse user can use below command
cmd > udevadm info -a -p $(udevadm info -q path -n /dev/input/mouse)
P.S.: cmd stands for the command shell (Terminal).The above procedure is working with any USB device.

Answer 2

You may use MODULE_SOFTDEP macro defined in module.h in your driver where you can specify the name of the USB driver which gets loaded when the USB mouse is inserted. This will load your driver automatically. The depmod approach is the way to go.

Answer 3

Use MODULE_DEVICE_TABLE macro. That will export supported device table so that your hotplug tool (whether it udev or something else) can load your module. I've described the loading process in this answer.
To see example usage, refer to drivers/hid/usbhid/usbmouse.c. If this driver compiled as module, it is loaded every time any usb mouse is attached.