Hardware is a pain. This presentation give a birds eye view on the way to program drivers on a Linux Based Machine. video : https://www.youtube.com/watch?v=rr-lKnxLfB4 report : http://www.slideshare.net/shivekkhurana/driver-programming-report

1. Driver Programming
. Sa
ha ,
. Sh
us e Inno a on en
Un e s
O De h
e
e

2. Hardware is complicated
1.
2.
3.
4.
Mu
p e
Mu
p e
O e app
No enou
endo s
e s ons
n
un
ona
h sma
p o amme s
HARDWARE

3. Drivers simplify them
1.
2.
3.
4.
So wa e oun e pa s o ha dwa e
Hand e mu
p e HW e s ons
Hand e mu
p e HW endo s
Do h s a oss d
e en OS(es)
DRI ER

4. Outline
1.
2.
3.
4.
5.
The L nux e ne
T pes o De
e D
e s( ene a )
ha / B o
De
e D e s
Ne wo In e a es
Demo

5. Linux and Linus
1. W
en b L nus To a ds (Un e s
o He s n )
2. He wan ed a s s em be e
han UNIX,
and MINIX
3. “The a
den a
e o u ona .”

6. The Linux Device Paradigm
HARDWARE

7. The Linux Device Paradigm
HARDWARE
ERNEL

8. The Linux Device Paradigm
HARDWARE
ERNEL
USER SPA E

9. The Linux Device Paradigm
HARDWARE
ERNEL
USER SPA E
SHELL

10. Drivers are
DRI ER
HARDWARE
ERNEL

11. The Linux Device Paradigm
DRI ER
HARDWARE
ERNEL
USER SPA E

12. The Linux Device Paradigm
HARDWARE
ERNEL
USER SPA E
D nam
Load n

13. The Linux Device Paradigm
DRI ER
HARDWARE
ERNEL
USER SPA E
D nam
Load n

14. Types of drivers
1.
ha
De
es
DRI ER
1
0
1
0
1

15. Types of drivers
1
2. B o
De
es
DRI ER
0
1
0
1
1
0
1
0
1
1
1
0
0
1
1
1
0
0
1
1
0
0
0
1
1
0
0
0
1
1
0
1
1
0
1
0
1
1
0

16. Types of drivers
3. Ne wo
In e
a es
DRI ER
T P/UDP
P
P

17. Driver is a module
E e
e ne
ex ens on
DRI ER
s a Modu e

18. Driver is a module
E e
e ne
ex ens on
DRI ER
MODULE
s a Modu e

19. A device is represented as a file
And o
ead w
ead/ w
e he
e
he ph s
e
a
de
e, we

20. Process
HARDWARE
DE I E
ONTROLLER
ERNEL
DRI ER
DE I E FILE
USER SPA E

21. Programming Process
De
e struct
s u u e o ho d da a pes o
ommun a e w h he de
es. Th s ma
o espond o a ua p ns.

22. Programming Process
F
e ope a ons
A de e o he use spa e s us a
F e ope a ons maps
e RUD o de
e.
e.

23. Programming Process
En
po n s
The e s no main() n modu es. Be ause
modu e s no an exe u ab e. So we need
de ne en
po n s manua
o oad
de
e.
o

24. Major Numbers
Ea h de
e d
den
e wh
and s un que
e
h
o
has a ma o numbe
s ass ned on un me
a
de es

25. Execution Stack is small
No memo
s a
memo
s ese
o a ed on un me. A
ed a exe u on

26. Makefile
make s a nux app
a on ha
d
e s (so wa es n ene a )
omp
es

27. Attaching the module to kernel
nsmod ha _de
e. o
m nod /de / ha _de
e 251 0

28. Exit point
Ex
o
po n s a so needs o de ned manua
ea up he used e ne spa e

29. User space program
Open de
e
n e a
ons
e and pe
o m use
spa e

30. Demo