On 10.07.2018 11:11, Marek Vasut wrote: > On 07/10/2018 11:06 AM, Stefan Agner wrote: >> 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 > > But this will break mesa if it depends on mxsfb name for ie. etnaviv > binding. > Does it? grep -r -e mxsfb in libdrm and mesa master returns nothing. There is also .name in struct drm_driver, which is already set to mxsfb-drm... Is that the one exposed to user space? >> - 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. > > Can you fix the DTs for 4.19 too ? Getting tight, but will try. -- Stefan -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
