On 11.10.2016 11:33, Jani Nikula wrote: > On Tue, 11 Oct 2016, "Sun, Jing A" <jing.a....@intel.com> wrote: >> It's needed that DRM Driver module could be removed and reloaded after >> kernel booting on the projects that I have been working on, and I hope >> such module type change could be accepted. Looks like Iwai has similar >> change request as well. Would you please review it and let us know if >> any concerns? > Looking at the Kconfig, selecting CONFIG_DRM_MIPI_DSI is against the > recommendations of Documentation/kbuild/kconfig-language.txt: > > select should be used with care. select will force > a symbol to a value without visiting the dependencies. > By abusing select you are able to select a symbol FOO even > if FOO depends on BAR that is not set. > In general use select only for non-visible symbols > (no prompts anywhere) and for symbols with no dependencies. > That will limit the usefulness but on the other hand avoid > the illegal configurations all over.
All existing drivers which selects DRM_MIPI_DSI also depends on DRM. So the dependency is always true. I am not sure if it could not change in the future, but in such case mipi_dsi bus should be completely detached from DRM framework, I hope we have not such case yet :) > > Indeed, you may end up with CONFIG_DRM_MIPI_DSI=y and CONFIG_DRM=m, > which violates DRM_MIPI_DSI dependency on CONFIG_DRM. This is broken and > should be fixed. The suggested patch does *not* fix this issue. At the moment it should not be possible. Regards Andrzej