Hello,
I’m adapting the imx185 camera driver for my board (2-lane and other things). I have a question on the devname for the device.
The devtree included in 4.4.38 specifies the name as “imx185 30-001a”. With this setup I would always crash nvcamera-daemon (V4L2Device not available), while I could enumerate the device and capture with the v4l commands. After a long evening of strace and debug, I discovered nvcamera-daemon tried to open “imx185 6-001a”. Lo and behold, changing the devname in the devtree made it work.
But I could not find documentation of devname or show it should be set. What is the magic behind it? How does nvcamera-daemon conclude the name as “imx185 6-001a”?
Thanks!
@EmbeddedRod
The reference IMX185 is connected behind an I2C MUX so that the name is “imx185 30-001a” if your HW didn’t implement I2C MUX and connect to the i2c bus 6 the name should be “imx185 6-001a”
Thanks Shane, that makes sense as I have remove the MUX. But how does then nvcamera-daemon get the name of the device? I never pass it anywhere in the configuration. Does it parse the device, tree, see there is no mux and then make up “imx185 6-001a” by itself? Is there some documentation (or source) on how nvcamera-daemon calculates the name?
Thanks!
@EmbeddedRod
Right it’s from the DT. You can check it runtime to make sure your DT is consistence.
Check all the name in
/proc/device-tree/…