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lnx

Misc tests/projects/patches for linux.

gpio_test

Simple test driver for gpio. Allows manipulating gpio output value. Gpio number is set as driver parameter. To write 0 or 1 one needs to do echo 0 > /dev/gpio_test or echo 1 > /dev/gpio_test.

modinfo:

root@omapl138-lcdk:~# modinfo gpio_test.ko
  filename:       gpio_test.ko
  description:    Gpio test driver.
  author:         Michael Likholet <[email protected]>
  license:        GPL
  depends:        
  vermagic:       3.1.10 preempt mod_unload modversions ARMv5 
  parm:           gpio_num:ushort

how to use:

Build driver


  ┌─(11:29:09)─(michael@host)─(~/Proj/free/linux/gpio_driver/lnx/gpio_test)
  └─► make
  Make module...                                                                                            
  make[1]: Entering directory `/home/michael/ti/linux-3.1.10'                                               
  CC [M]  /home/michael/Proj/free/linux/gpio_driver/lnx/gpio_test/gpio_test.o                             
  /home/michael/Proj/free/linux/gpio_driver/lnx/gpio_test/gpio_test.c: In function 'gpio_test_cdev_start':  
  /home/michael/Proj/free/linux/gpio_driver/lnx/gpio_test/gpio_test.c:99:2: warning: format not a string lit
  Building modules, stage 2.                                                                              
  MODPOST 1 modules                                                                                       
  CC      /home/michael/Proj/free/linux/gpio_driver/lnx/gpio_test/gpio_test.mod.o                         
  LD [M]  /home/michael/Proj/free/linux/gpio_driver/lnx/gpio_test/gpio_test.ko                            
  make[1]: Leaving directory `/home/michael/ti/linux-3.1.10'

Copy it to filesystem and insert it.

  root@omapl138-lcdk:~# insmod gpio_test.ko gpio_num=43

Have fun.

  root@omapl138-lcdk:~# while sleep 0.1; do echo 1 > /dev/gpio_test; sleep 0.1; echo 0 > /dev/gpio_test; done;

Now you can take the probe and see result:

omap_l138

Patch for omap-l138 kernel (kernel with patches at gitorious.org, board description - TI LCDK module):

Enables CLKOUT (24MHz, internal clock) at TP10, which is used as clock source for external camera connected to J16.
Setup reset pin for camera.
Setup all the pins for camera (DIN0-DIN15).
Added driver for ov5642 to config.
ov5642 enumerated in i2c board info.

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