Hi On Wed, 24 Mar 2010, Adam Sutton wrote: > Hi, > > I'm just beginning a Linux based project running on a Freescale i.MX25. > One of > my jobs is to write a camera driver for the sensor we're going to be > using > (Omnivision 7675). However at present I only have access to an ov2640 > attached > to a Freescale 3stack development board. I thought it would be a useful > and > interesting exercise to port the driver provided by Freescale to the new > > soc_camera framework. > > I've written the ov2640 driver, using a variety of other drivers as > references > and I'm using the mx25_camera host driver (with a few mods) posted by > Arno > Euteneuer. After getting over some basic setup/config problems I've now > got as > far as the mx25_camera loading and this then auto loading the ov2640. > This > correctly probes the I2C and detects the sensor. > > However I've now come up against a problem that I'm unsure of how to > solve and > I'm not sure whether its a case of my not properly following the current > > framework. soc_camera_probe() is called and detects the the > soc_camera_link > object contains board information and therefore calls > soc_camera_init_i2c() this > in turn calls v4l2_i2c_new_subdev_board() which then attempts to create > a new > i2c_client (i2c_new_device()) and it is at this point things fail. > > Because an i2c_client already exists (auto created from the static board > info > registered by the platform configuration), the one passed into the > probe() > routine of my chip driver, the i2c_new_device() call fails as it believe > the > device is busy as a client already exists for that I2C address. > > I can only assume that there is something wrong with the way I've set > things up > / used the framework. However I've compared it to several other modules > and > can't see any obvious faults (although its not obvious which drivers > represent > the current "preferred" approach). > > I should say that I'm using a 2.6.31 based kernel (provided by > Freescale) into > which I've grafted the 2.6.33 media drivers (and obvious dependencies) > so I > guess something about this graft could be causing the problem. Though I > cannot > see what from looking at other changes. Your board shouldn't register static i2c devices for cameras. See any (soc-)camera-enabled platform in the _current_ kernel. E.g., arch/arm/mach-mx3/mach-pcm037.c. However, for us to be able to really help you, you have to base your work on current development kernel, or at least on a recent release (2.6.33 / 2.6.34-rc2). Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
