On 16.06.2018 01:32, Marek Vasut wrote: > On 06/16/2018 12:42 AM, Leonard Crestez wrote: >> On Fri, 2018-06-15 at 23:36 +0200, Marek Vasut wrote: >>> On 06/15/2018 10:58 PM, Leonard Crestez wrote: >>>> On Fri, 2018-06-15 at 16:47 -0300, Fabio Estevam wrote: >>>>> On Fri, Jun 15, 2018 at 4:43 PM, Leonard Crestez >>>>> <leonard.crestez@xxxxxxx> wrote: >> >>>>>> The FBDEV driver uses the same name and both can't be registered at the >>>>>> same time. Fix this by renaming the drm driver to mxsfb-drm >>>>> >>>>> Stefan sent the same patch a few days ago: >>>> >>>> In that thread there is a proposal for removing the old fbdev/mxsfb >>>> driver entirely. >>>> >>>> That would break old DTBs, isn't this generally considered bad? Also, >>>> are we sure the removal of fbdev/mxsfb wouldn't lose any features? >>>> >>>> What my series does is make both drivers work with the same kernel >>>> image and turns the choice into a board-level dtb decision. Supporting >>>> everything at once seems desirable to me and it allows for a very >>>> smooth upgrade path. >>> >>> Having two drivers in the kernel with different set of bugs is always bad. >>> >>>> The old driver could be removed later, after all users are converted. >>> >>> Both drivers were in for long enough already. And let's be realistic, >>> how many MX23/MX28 users of old DTs with new kernels are there who >>> cannot update the DT as well ? >> >> Grepping for "display =" in arch/arm/boot/dts/imx* I see that old >> bindings are also used by 3rd-party boards for imx6/7: >> * imx6sx-nitrogen6sx >> * imx6ul-geam >> * imx6ul-isiot >> * imx6ul-opos6uldev >> * imx6ul-pico-hobbit >> * imx6ul-tx6ul >> * imx7d-nitrogen7 > > Er, yes, a handful of boards which could be updated :) > >> Converting everything might be quite a bit of work, and explicitly >> supporting old bindings is also work. > > Does adding support for old bindings justify the effort invested ? I > doubt so, it only adds more code to maintain. > >> It is very confusing that there is a whole set of displays for imx6/7 >> which are supported by upstream but only with a non-default config. >> While it is extremely common in the embedded field to have custom >> configs the default one in the kernel should try to "just work". >> >> Couldn't this patch series be considered a bugfix? It was also >> surprisingly small. > > I think it's just a workaround which allows you to postpone the real > fix, and I don't like that. This is one of the situation where states quo is kinda the worst situation. Currently imx_v6_v7_defconfig and mxs_defconfig actually still uses CONFIG_FB_MXS. I understand that you'd rather prefer to move forward. I suggest we do it in steps. In 4.19: - Change DRM driver.name to mxsfb-drm so we avoid conflicts for now - Remove CONFIG_FB_MXS from imx_v6_v7_defconfig/mxs_defconfig now, and only enable CONFIG_DRM_MXSFB=y - Add (deprecated) to CONFIG_FB_MXS In 4.19/4.20: - Fix the above device trees In 4.20/4.21: - Remove FB_MXS Does that sound reasonable? If yes, I can send the patch set to do step 1. -- Stefan _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
