Re: [PATCH/RFC i2c/for-next] i2c: rcar: Add per-Generation fallback bindings
On Thu, Dec 01, 2016 at 04:18:14PM +0100, Simon Horman wrote: > In the case of Renesas R-Car hardware we know that there are generations of > SoCs, e.g. Gen 2 and Gen 3. But beyond that its not clear what the > relationship between IP blocks might be. For example, I believe that > r8a7790 is older than r8a7791 but that doesn't imply that the latter is a > descendant of the former or vice versa. > > We can, however, by examining the documentation and behaviour of the > hardware at run-time observe that the current driver implementation appears > to be compatible with the IP blocks on SoCs within a given generation. > > For the above reasons and convenience when enabling new SoCs a > per-generation fallback compatibility string scheme being adopted for > drivers for Renesas SoCs. > > Also deprecate renesas,i2c-rcar. It seems poorly named as it is only > compatible with R-Car Gen 1. It also appears unused in mainline. > > Signed-off-by: Simon HormanSorry, I seem to have omitted the driver (C code) portion of this change. I send v2.
Re: [PATCH/RFC i2c/for-next] i2c: rcar: Add per-Generation fallback bindings
Hi Simon, On Thu, Dec 1, 2016 at 4:18 PM, Simon Hormanwrote: > In the case of Renesas R-Car hardware we know that there are generations of > SoCs, e.g. Gen 2 and Gen 3. But beyond that its not clear what the > relationship between IP blocks might be. For example, I believe that > r8a7790 is older than r8a7791 but that doesn't imply that the latter is a > descendant of the former or vice versa. > > We can, however, by examining the documentation and behaviour of the > hardware at run-time observe that the current driver implementation appears > to be compatible with the IP blocks on SoCs within a given generation. > > For the above reasons and convenience when enabling new SoCs a > per-generation fallback compatibility string scheme being adopted for > drivers for Renesas SoCs. > > Also deprecate renesas,i2c-rcar. It seems poorly named as it is only > compatible with R-Car Gen 1. It also appears unused in mainline. > > Signed-off-by: Simon Horman > --- > Documentation/devicetree/bindings/i2c/i2c-rcar.txt | 32 > ++ > 1 file changed, 20 insertions(+), 12 deletions(-) > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt > b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt > index 239632a0d709..8c679b17c4c6 100644 > --- a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt > +++ b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt > @@ -1,17 +1,25 @@ > I2C for R-Car platforms > > Required properties: > -- compatible: Must be one of > - "renesas,i2c-rcar" > - "renesas,i2c-r8a7778" > - "renesas,i2c-r8a7779" > - "renesas,i2c-r8a7790" > - "renesas,i2c-r8a7791" > - "renesas,i2c-r8a7792" > - "renesas,i2c-r8a7793" > - "renesas,i2c-r8a7794" > - "renesas,i2c-r8a7795" > - "renesas,i2c-r8a7796" > +- compatible: > + "renesas,i2c-r8a7778" if the device is a part of a R8A7778 SoC. > + "renesas,i2c-r8a7779" if the device is a part of a R8A7797 SoC. > + "renesas,i2c-r8a7790" if the device is a part of a R8A7790 SoC. > + "renesas,i2c-r8a7791" if the device is a part of a R8A7791 SoC. > + "renesas,i2c-r8a7792" if the device is a part of a R8A7792 SoC. > + "renesas,i2c-r8a7793" if the device is a part of a R8A7793 SoC. > + "renesas,i2c-r8a7794" if the device is a part of a R8A7794 SoC. > + "renesas,i2c-r8a7795" if the device is a part of a R8A7795 SoC. > + "renesas,i2c-r8a7796" if the device is a part of a R8A7796 SoC. > + "renesas,i2c-rcar-gen1" for a generic R-Car Gen1 compatible device. > + "renesas,i2c-rcar-gen2" for a generic R-Car Gen2 compatible device. > + "renesas,i2c-rcar-gen3" for a generic R-Car Gen3 compatible device. Please use "renesas,-" when adding family-specific compatible values where non are defined yet. I.e. "renesas,rcar-gen1-i2c" "renesas,rcar-gen1-i2c" "renesas,rcar-gen1-i2c" > + "renesas,i2c-rcar" (deprecated) > + > + When compatible with the generic version, nodes must list the > + SoC-specific version corresponding to the platform first followed > + by the generic version. > + > - reg: physical base address of the controller and length of memory mapped >region. > - interrupts: interrupt specifier. > @@ -33,7 +41,7 @@ Examples : > i2c0: i2c@e6508000 { > #address-cells = <1>; > #size-cells = <0>; > - compatible = "renesas,i2c-r8a7791"; > + compatible = "renesas,i2c-r8a7791", "renesas,i2c-rcar-gen2"; "renesas,rcar-gen2-i2c". Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
[PATCH/RFC i2c/for-next] i2c: rcar: Add per-Generation fallback bindings
In the case of Renesas R-Car hardware we know that there are generations of SoCs, e.g. Gen 2 and Gen 3. But beyond that its not clear what the relationship between IP blocks might be. For example, I believe that r8a7790 is older than r8a7791 but that doesn't imply that the latter is a descendant of the former or vice versa. We can, however, by examining the documentation and behaviour of the hardware at run-time observe that the current driver implementation appears to be compatible with the IP blocks on SoCs within a given generation. For the above reasons and convenience when enabling new SoCs a per-generation fallback compatibility string scheme being adopted for drivers for Renesas SoCs. Also deprecate renesas,i2c-rcar. It seems poorly named as it is only compatible with R-Car Gen 1. It also appears unused in mainline. Signed-off-by: Simon Horman--- Documentation/devicetree/bindings/i2c/i2c-rcar.txt | 32 ++ 1 file changed, 20 insertions(+), 12 deletions(-) diff --git a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt index 239632a0d709..8c679b17c4c6 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt @@ -1,17 +1,25 @@ I2C for R-Car platforms Required properties: -- compatible: Must be one of - "renesas,i2c-rcar" - "renesas,i2c-r8a7778" - "renesas,i2c-r8a7779" - "renesas,i2c-r8a7790" - "renesas,i2c-r8a7791" - "renesas,i2c-r8a7792" - "renesas,i2c-r8a7793" - "renesas,i2c-r8a7794" - "renesas,i2c-r8a7795" - "renesas,i2c-r8a7796" +- compatible: + "renesas,i2c-r8a7778" if the device is a part of a R8A7778 SoC. + "renesas,i2c-r8a7779" if the device is a part of a R8A7797 SoC. + "renesas,i2c-r8a7790" if the device is a part of a R8A7790 SoC. + "renesas,i2c-r8a7791" if the device is a part of a R8A7791 SoC. + "renesas,i2c-r8a7792" if the device is a part of a R8A7792 SoC. + "renesas,i2c-r8a7793" if the device is a part of a R8A7793 SoC. + "renesas,i2c-r8a7794" if the device is a part of a R8A7794 SoC. + "renesas,i2c-r8a7795" if the device is a part of a R8A7795 SoC. + "renesas,i2c-r8a7796" if the device is a part of a R8A7796 SoC. + "renesas,i2c-rcar-gen1" for a generic R-Car Gen1 compatible device. + "renesas,i2c-rcar-gen2" for a generic R-Car Gen2 compatible device. + "renesas,i2c-rcar-gen3" for a generic R-Car Gen3 compatible device. + "renesas,i2c-rcar" (deprecated) + + When compatible with the generic version, nodes must list the + SoC-specific version corresponding to the platform first followed + by the generic version. + - reg: physical base address of the controller and length of memory mapped region. - interrupts: interrupt specifier. @@ -33,7 +41,7 @@ Examples : i2c0: i2c@e6508000 { #address-cells = <1>; #size-cells = <0>; - compatible = "renesas,i2c-r8a7791"; + compatible = "renesas,i2c-r8a7791", "renesas,i2c-rcar-gen2"; reg = <0 0xe6508000 0 0x40>; interrupts = <0 287 IRQ_TYPE_LEVEL_HIGH>; clocks = <_clks R8A7791_CLK_I2C0>; -- 2.7.0.rc3.207.g0ac5344