Mipi CSI-2 LT6911UXC driver issue

Hi All,

We trying to implment LT6911UXC CSI-2 driver in Jetson Xavier NX platform,
based on Nvidia kernel driver (which found under kernel_src/kernel/nvidia/drivers/media/i2c)
and device tree that based on some example in this forum.

The LT6911uxc assemble on Avidea B112 board.

During the kernel load the LT6911 IC identify, but everytime the kernel boot we got issue regarding the Voltage regulators sampling:

This parameters in the kernel driver: pdata->regulators.avdd, pdata->regulators.dvdd, pdata->regulators.iovdd.
(They are not defined in the dts file).

which lead to this error prints:

[ 2.027356] lt6911uxc 2-002b: probing lt6911uxc v4l2 sensor at addr 0x2b
[ 2.027449] lt6911uxc 2-002b: mclk absent,assuming sensor driven externally
[ 2.027473] lt6911uxc 2-002b: camera_common_regulator_get vana ERR: ffffffffffffffed
[ 2.027478] lt6911uxc 2-002b: lt6911uxc_power_get: unable to get regulator(s)
[ 2.027482] lt6911uxc 2-002b: unable to power get
[ 2.027487] lt6911uxc 2-002b: tegra camera driver registration failed
[ 2.027563] lt6911uxc: probe of 2-002b failed with error -14

if i comments this lines in the kernel driver (in the function: lt6911uxc_power_get)
i got messages that the device bonded:

[ 2.060581] lt6911uxc 2-002b: probing lt6911uxc v4l2 sensor at addr 0x2b
[ 2.061321] lt6911uxc 2-002b: mclk absent,assuming sensor driven externally
[ 2.061659] lt6911uxc 2-002b: tegracam sensor driver:lt6911uxc_v2.0.6
[ 2.062991] lt6911uxc 2-002b: detected lt6911uxc sensor
[ 3.241336] tegra194-vi5 15c10000.vi: subdev lt6911uxc 2-002b bound

but in this case i dont found “Video0” node under device and therefore can`t debug the video with:v4l2-ctl utility.

So my questions:
a. What are other ways do i have to debug this issues ?
b. Why i dont get Video0 dev node ?
c. Does Nvidia dont have any proper solution to get HDMI inputs on the Jetson family ?
Is there any solution will be made in the future ?

i upload my device tree for overview.

Many thanks for any assist.

tegra194-csi-lt6911uxc.dtsi (6.9 KB)

After comments this lines:
avdd-reg = “vana”;
iovdd-reg = “vif”;
dvdd-reg = “vdig”;

the LT6911uxc seems to register the driver ok (subdev lt6911uxc 2-002b bound)
and i dont get error about: camera_common_regulator_get vana ERR: ffffffffffffffed
and even when sampling the 1.8v, 3.3v and 5v on the B112 card they are ok and exist.

However there is no Video0 node under dev, (i disable all IMX219 logic on the dts file),
and therefore i can`t debug it (maybe this is hardware issue).
How can i overcome on this, please assist.


Sorry for the late response, have you managed to get issue resolved or still need the support? Thanks

hello znroee,

you should assign the regulator settings to have power-supply to enable device correctly.
since you’re using customize board, could you please review the schematic, and please check all these 1v8, 3v3…etc regulators are provided correctly.

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