TX2 Device tree and driver connection

Hi all,

i have one question regarding DT and driver connection.

In the tegra186-camera-e3326-a00.dtsi there is a code with parameters for the camera

mode0 { // OV5693_MODE_2592X1944
	mclk_khz = "24000";
	num_lanes = "2";
	tegra_sinterface = "serial_c";
	discontinuous_clk = "no";
	dpcm_enable = "false";
	cil_settletime = "0";

	active_w = "2592";
	active_h = "1944";
	pixel_t = "bayer_bggr";
        readout_orientation = "90";
	line_length = "2688";
	inherent_gain = "1";
	mclk_multiplier = "6.67";
	pix_clk_hz = "160000000";

	min_gain_val = "1.0";
	max_gain_val = "16";
	min_hdr_ratio = "1";
	max_hdr_ratio = "64";
	min_framerate = "1.816577";
	max_framerate = "30";
	min_exp_time = "34";
	max_exp_time = "550385";
};
  1. can you tell me which driver and how it uses this parameters? I can’t find in the kernel source files that some of the drivers reads eg. tegra_sinterface = “serial_c”; ??

How is that used?

Br.

hello Joko_,

please download the [NVIDIA Tegra Linux Driver Package]
please check [Release 28.2 Development Guide]-> [Sensor Driver Programming Guide] for more details,
thanks

Hi JerryChang

thank you for replay.

  1. I have downloaded the documentation and read before asking here. I found the description of the parameters.

But which driver is using this parameters?

What will happen if not all parameters are set?

  1. IN the documentation is a line:
    NVIDIA provides OV5693 Bayer sensor as a sample. NVIDIA tunes this sensor for the Jetson platform. The drive code, based on the media controller framework, is available at:
    ./kernel/kernel4.4/drivers/media/i2c/ov5693.c

a) does this mean that the OV5693 is using the internal ISP of tegra X2?
b) if yes where is the tuning *.isp file (e3326_front_P5V27C.isp) for the OV5693 located?
c) what is the connection from the DT to the *.isp file ? Does the badge parameter in the
tegra186-camera-e3326-a00.dtsi has something with the ISP?

  1. Does the Argus use the internal ISP of tegra X2?
    Br.

hello Joko_,

reply several of your questions as below,
thanks

  1. there’s kernel driver reading the device tree properties, please check sensor_common_parse_*_props(…) functions for more details.
sources/kernel/kernel-4.4/drivers/media/platform/tegra/camera/sensor_common.c

a) yes, ov5693 is using the internal ISP of TX2
b) sorry, we don’t share the tuning files
c) correct, the badge property is an unique name that identifies the module.

  1. yes

Hello Jerry,

thank you for the update.

just one thing i don’t understand: you don’t share the .isp file (e3326_front_P5V27C.isp) for the development kit camera OV5693 (E3326) but the image when we start the camera on the dev. kit is great.

Where from does the ISP get the calibration data if there is no .isp file (after installing Jetpack) in order to have great picture?

Br.

hello Joko_,

we had tuning settings included in OV5693’s pre-build library,
also, according to [Sensor Driver Programming Guide]

developers must work with NVIDIA certified camera partners for any Bayer sensor and tuning support.

please contact our camera partners: https://developer.nvidia.com/embedded/community/partners if you need further support,
thanks