Hi Eizan, Firstly, about how to determine the master mdp driver, we also can judge the component type. The component type can be gotten by calling of_device_get_match_data(dev). If the component is MTK_MDP_RDMA, it is the master driver. No matter it is mdp_rdma0 or mdp_rdma1. Secondly, about supporting the multiple MDP master device nodes, you can try my advice in my previous comment after the completion of this series of patches. Thanks a lot. Regards, Houlong On Wed, 2021-08-18 at 15:43 +0800, Eizan Miyamoto wrote: > Hi Houlong, > > On Mon, Aug 16, 2021 at 1:00 PM houlong wei <houlong.wei@xxxxxxxxxxxx > > wrote: > > Hi Eizan, > > > > "mdp-rdma0" may be not the only one master device node. In fact, > > there > > are 2 "mdp-rdma" in mt8173. You can see "mdp_rdma1" via below link. > > > > https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/arch/arm64/boot/dts/mediatek/mt8173.dtsi?h=v5.13.11#n1016 > > If we add "mediatek,mt8173-mdp" to "mdp_rdma1" like below, we will > > have > > one more V4L2 video devie node. > > > > mdp_rdma1: rdma@14002000 { > > compatible = "mediatek,mt8173-mdp-rdma", > > "mediatek,mt8173-mdp"; > > ... > > } > > > > We should consider the case that there are more than one "MDP_RDMA" > > components. > > Would it be okay with you if we added support for multiple MDP master > device nodes in follow-up changes? My rationale is this: > - As far as I can tell, the mediatek integration with V4L2 currently > only handles a single MDP master device node. It's not clear to me > the > scope of changes that will be needed to make things work properly > with > multiple nodes. > - The patch series makes video decode work (admittedly, in light of > your comments not optimally) upstream, which is better than not > landing these changes at all. > > I'd like to say that I'm very open to (and excited about) discussing > further work to support multiple MDP master nodes, perhaps we can > work together on this so I can understand what needs to be done. > > Please let me know your thoughts, > > Eizan
