Re: v5.15-rcX regression: video devices on i.MX6 are not created

[Saravana Kannan]

On Mon, Oct 4, 2021 at 5:19 AM Krzysztof Hałasa <khalasa@xxxxxxx> wrote:
>
> Hi Saravana et al.,
>
> FYI the patch: 6b2117ad65f1bca9ece6d4b1ee784b42701a2d86
>
> of: property: fw_devlink: Add support for "resets" and "pwms"
>
> Allows better tracking of dependencies between devices.
>
>  drivers/of/property.c | 4 ++++
>
> breaks v4l2 video devices on an i.MX6 CPU. The /dev/video* nodes are not
> created, and the drivers (async subdevicess) are "waiting":
>
> # cat /sys/kernel/debug/v4l2-async/pending_async_subdevices
>
> imx-media:
>  [fwnode] dev=nil, node=/soc/ipu@2400000/port@0
>  [fwnode] dev=nil, node=/soc/ipu@2400000/port@1
>  [fwnode] dev=nil, node=/soc/ipu@2800000/port@0
>  [fwnode] dev=nil, node=/soc/ipu@2800000/port@1
> imx6-mipi-csi2:
>  [fwnode] dev=0-0036, node=/soc/bus@2100000/i2c@21a0000/camera@36
> ipu2_csi1_mux:
> ipu1_csi0_mux:
>  [fwnode] dev=21dc000.mipi, node=/soc/bus@2100000/mipi@21dc000
>
> Reverting the patch (or commenting the "resets" out) fixes the problem:
>
> # cat /sys/kernel/debug/v4l2-async/pending_async_subdevices
> ipu2_csi1:
> ipu2_csi0:
> ipu1_csi1:
> ipu1_csi0:
> imx-media:
> imx6-mipi-csi2:
> ipu2_csi1_mux:
> ipu1_csi0_mux:
>
>
> What now?

Hi Krzysztof,

Can you give me the following details?

1. The dts file that corresponds to the device you are testing this on.
2. Output of <debugfs>/devices_deferred base on at least 5.15-rc4 (I
added more info there recently).

That should tell me all the info I need to debug this. In the end
it'll essentially boil down to a reset controller driver not using
device driver model to initialize the device and directly parsing the
node in some kind of initcall.

Thanks,
Saravana
> --
> Krzysztof "Chris" Hałasa
>
> Sieć Badawcza Łukasiewicz
> Przemysłowy Instytut Automatyki i Pomiarów PIAP
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