Hi, On 10/26/2017 06:13 AM, Archit Taneja wrote: > Hi, > > On 10/26/2017 06:39 AM, Brian Norris wrote: >> On Wed, Oct 25, 2017 at 03:57:19AM -0400, Sean Paul wrote: >>> Archit asked a question about moving to >>> dw-mipi-dsi >> >> That question made me think though: this approach seems backwards. It >> seems like someone did copy/paste/fork, and then we're asking the >> authors of the original driver to un-fork? It seems like this should >> happen the other way around -- those trying to support a new incarnation >> should have looked to try to abstract the original driver for their >> uses first. > > Yes, ST wanted to replicate rockchip's version of the mipi DSI driver and > put it in their folder. If they did that, their KMS driver would have been > the third driver to implement a third instance of the DW DSI controller > driver. > Hisilicon and Rockchip being the other 2. > > It was either that or attempt at a common DSI DW bridge driver. I suggested > the latter. > > The ST guys have abstracted out the PHY pieces, which they knew varied > between > rockchip and ST. Ideally, they should have also tried to create a RFC > patch to > make the rockchip driver use the bridge too. But they didn't do that, and > the rockchip or hisilicon people were interested in even looking at it, > even after I CC'ed them. > >> >> IIUC, that's exactly what Rockchip did for much of their Analogix eDP >> code -- they reworked the Exynos DP driver to split common Analogix code >> from any Exynos-specific bits. > > I get that. I had hoped either ST or Rockchip guys would have done the > similar > thing, but no one volunteered. > >> >> And actually, the current stuff in >> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c is completely unused. It >> exports some functions, but I see no users of it. Is that intended? Is > > The ST kms driver uses it: > > drivers/gpu/drm/stm/dw_mipi_dsi-stm.c > I confirm STM32 chipsets use the Synopsys dw dsi bridge driver. I plan to improve this bridge driver by adding new features (see todos + dsi read, command mode with bta & gpio...). For the first commit, I did my best to keep the source code as close as possible to the Rockchip version, in order to ease the port for Rockchip guys. >> somebody already working on refactoring existing Rockchip code to use >> this? > > I don't know. If rockchip isn't interested in doing it, we can check with > Philippe from ST if he can try creating a RFC that converts the rockchip > driver to use the dw-mipi-dsi driver. I am not really interested in doing this port for Rockchip (or Hisilicon or i.MX...) but happy to help anyone that wants to use the dw-mipi-dsi bridge driver :) Many thanks, Philippe :) > > Thanks, > Archit > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
