Hi Sri, On 03/31/14 23:12, Sriakhil Gogineni wrote: > Hi, > > I'm trying to write a HDMI-CEC driver for the Radxa Rock > (Specification - Radxa). I am coming from a software background and > have found libcec and am looking at other implementation. > > I'm wondering how to connect the hardware and software pieces under > Linux / Android. > > I'm not sure if I need to find out what /dev/ its exposed under via > the device tree or determine which register is used from the data > sheet? > > Any advice / tips / pointers would be helpful. There is currently no kernel CEC support available. What makes cec complex is 1) the CEC specification is horrible :-) and 2) a proper cec implementation has to be able to take care of v4l2 devices, drm/kms devices and usb dongles. In addition, at least some of the CEC handling has to take place in the kernel in order to handle the audio return channel, suspend commands, hotplug-over-CEC and such advanced features. I have been working on this, but it is a background project and I never found the time to finish it. My latest code is available here: http://git.linuxtv.org/hverkuil/media_tree.git/shortlog/refs/heads/cec but it needs more work to make this ready for prime time. It works, but it needs cleanup and cec_claim_log_addrs() needs improvement. Particularly when called from a driver: this needs to be done in non- blocking mode which isn't yet working (in blocking mode the driver would block for an unacceptable amount of time). If you or someone else would be willing to take over, I would have no objections. I have no idea when I might have time to continue work on this. Regards, Hans -- 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
