2008-09-05 10:38:56     v4l_test and the MT9V022 driver

Document created by Aaronwu Employee on Aug 7, 2013
Version 1Show Document
  • View in full screen mode

2008-09-05 10:38:56     v4l_test and the MT9V022 driver


Message: 61702   


Has anyone used the v4l_test program with the MT9V022 driver?  I am using it, but I had to change something in v4l_test.c to make it work...


The function try_format() uses the VIDIOCSPICT ioctl command to make sure the default format and depth defined in v4l_test.c match that of the underlying driver.  In the case of MTV022,  this fails because v4l_test is hardcoded to VIDEO_PALETTE_YUV422 16-bit pixeldepth; however, the mtv022.h file uses VIDEO_PALETTE_GREY 8-bit pixeldepth.


Am I doing something wrong, or is this just known to not work without modification for the mtv022?  I'll be glad to submit a new v4l_test.c that allows the user to override these defaults; but first I wanna make sure I understand it.


Anyone know?




2008-09-05 11:40:31     Re: v4l_test and the MT9V022 driver

Mike Frysinger (UNITED STATES)

Message: 61707   


i'm pretty sure your experience and description are correct.  the default v4l test code expects certain formats and simply bombs on any other.


i think the code you're working with comes from linux-2.6.x/Documentation/ ?  that v4l test code is maintained by the v4l guys, so if you write a patch, you should e-mail it to v4l-dvb-maintainer@linuxtv.org