On 11/25/2016 03:06 PM, Fabio Estevam wrote: > Hi Vladimir, > > On Fri, Nov 25, 2016 at 11:00 AM, Vladimir Zapolskiy > <vladimir_zapolskiy at mentor.com> wrote: > >> according to the DTSI files in the vanilla kernel DW HDMI IP is found >> only on iMX6Q/D and iMX6DL/iMX6S SoCs (but please double check it), >> so this approach should work ideally. > > After thinking more about this I think we can not get rid of "gpr". If > we have a new i.MX SoC that is not compatible with > "fsl,imx6q-iomuxc-gpr" then the lookup will fail. >
Practically and when it becomes needed it should be possible to add SoC specific hooks related to IOMUX_GPRx controls on basis of device compatibles bound to the SoC variant. Hypothetically if in future there is one more iMX SoC with a similar PCIe or SATA controller but different GPR controls, to preserve backward compatibility with old iMX6* DTB firmware the same handling of device compatibles must be done in the drivers. >> I see that the same has already been done in PCIe and SATA drivers, >> but please consider to send a similar change against iMX LDB driver > > The i.MX LDB driver is also used on imx53, so we cannot search for > "fsl,imx6q-iomuxc-gpr" compatible, as it will fail on imx53. > > So it seems we need to keep the "gpr" property in this case. > Right, I missed it. By chance GPR controls of LDB/LVDS are the same on iMX53 and iMX6*, otherwise the driver shall care about GPR controls differently, for example get a SoC specific GPR device compatible. Nevertheless it is just a suggestion and it may remain just a mental exercise of how to beautify/standardize iMX device binding descriptions. -- With best wishes, Vladimir