How to unload mxc_ipuv3_fb?

[jotes]

Hello,

In our project we want to load mxc_ipuv3_fb driver as a module and unload it when it is not used. We have no problem with loading it (for example to work with ldb driver), but when we are trying to unload, it shows:

# modprobe -r mxc_ipuv3_fb

modprobe: can't unload module mxc_ipuv3_fb: Resource temporarily unavailable

# lsmod

Module                  Size  Used by    Tainted: P

mxc_ipuv3_fb           44938  1

ldb                     9401  0

mxc_dispdrv             1705  2 mxc_ipuv3_fb,ldb

My question is, how to stop mxc_ipuv3_fb and unload it properly?

Basically, we want to do this because we need to register two drivers to one Display Interface (more specifically, we want to connect HDMI driver and CVBS driver to IPU0 DI1, and let the userspace application choose between them). Is there any other way to do this (without reloading display module)?

[igorpadykov]

Hi jotes

resource can be used by other ipu drivers described

in sect.6.3 Source Code Structure attached Linux Manual and

one can try to analyze their dependencies and first unload driver which uses

mxc_ipuv3_fb.

Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

[jotes · Accepted solution]

Thanks, Igor.

The only way to unload the module was to build kernel with CONFIG_MODULE_FORCE_UNLOAD option and then use command: rmmod -f mxc_ipuv3_fb.
But loading the HDMI driver as a kernel module seemed to be too complicated, so we changed our project's plans.