HI Neil On 07/26/2018 10:13 PM, Neil Armstrong wrote: > The order between "syscon" and "simple-mfd" is important because in these > particular cases, the node needs to be first a "simple-mfd" to expose > it's sub-nodes, and later on a "syscon" to permit other nodes to access > this register space through the "syscon" mechanism. >
could you explain a bit which specific case that it need compatible "simple-mfd" come first? is this a problem in kernel side? because I see you have a comment below about problem in U-Boot.. also while Rob review the mmc-clkc patch, he raise a suggestion to drop "syscon" in drivers/mfd/syscon.c, see [1], will that solve or affect your problem? [1] https://lkml.kernel.org/r/CAL_Jsq+r+7BaJAPBn3L26sdxATVyDiuC=v3xe+yz0-27q0r...@mail.gmail.com > Signed-off-by: Neil Armstrong <narmstr...@baylibre.com> > --- > This also has a consequence for U-Boot since the U-Boot DM is much simpler > and can only associate a single device to a node, thus here we want these > nodes to be an mfd bus to be able to probe the sub-nodes. > > arch/arm64/boot/dts/amlogic/meson-axg.dtsi | 4 ++-- > arch/arm64/boot/dts/amlogic/meson-gx.dtsi | 4 ++-- > 2 files changed, 4 insertions(+), 4 deletions(-) > > diff --git a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi > b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi > index 6adc8d3..3f0de9d 100644 > --- a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi > +++ b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi > @@ -342,7 +342,7 @@ > ranges = <0x0 0x0 0x0 0xff63c000 0x0 0x1c00>; > > sysctrl: system-controller@0 { > - compatible = "amlogic,meson-axg-hhi-sysctrl", > "syscon", "simple-mfd"; > + compatible = "amlogic,meson-axg-hhi-sysctrl", > "simple-mfd", "syscon"; > reg = <0 0 0 0x400>; > > clkc: clock-controller { > @@ -1180,7 +1180,7 @@ > ranges = <0x0 0x0 0x0 0xff800000 0x0 0x100000>; > > sysctrl_AO: sys-ctrl@0 { > - compatible = "amlogic,meson-axg-ao-sysctrl", > "syscon", "simple-mfd"; > + compatible = "amlogic,meson-axg-ao-sysctrl", > "simple-mfd", "syscon"; > reg = <0x0 0x0 0x0 0x100>; > > clkc_AO: clock-controller { > diff --git a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi > b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi > index b8dc4db..d88699f 100644 > --- a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi > +++ b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi > @@ -344,7 +344,7 @@ > ranges = <0x0 0x0 0x0 0xc8100000 0x0 0x100000>; > > sysctrl_AO: sys-ctrl@0 { > - compatible = "amlogic,meson-gx-ao-sysctrl", > "syscon", "simple-mfd"; > + compatible = "amlogic,meson-gx-ao-sysctrl", > "simple-mfd", "syscon"; > reg = <0x0 0x0 0x0 0x100>; > > pwrc_vpu: power-controller-vpu { > @@ -431,7 +431,7 @@ > ranges = <0x0 0x0 0x0 0xc883c000 0x0 0x2000>; > > sysctrl: system-controller@0 { > - compatible = "amlogic,meson-gx-hhi-sysctrl", > "syscon", "simple-mfd"; > + compatible = "amlogic,meson-gx-hhi-sysctrl", > "simple-mfd", "syscon"; > reg = <0 0 0 0x400>; > }; > >
