| Message ID | 1473472551-11149-2-git-send-email-brendanhiggins@google.com |
|---|---|
| State | Superseded |
| Headers | show |
On Fri, Sep 09, 2016 at 06:55:51PM -0700, Brendan Higgins wrote: > Added device tree binding documentation for Aspeed I2C controller and > busses. > > Signed-off-by: Brendan Higgins <brendanhiggins@google.com> > --- > Changes for v2: > - None > --- > .../devicetree/bindings/i2c/i2c-aspeed.txt | 63 ++++++++++++++++++++++ > 1 file changed, 63 insertions(+) > create mode 100644 Documentation/devicetree/bindings/i2c/i2c-aspeed.txt > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt > new file mode 100644 > index 0000000..df68f2a > --- /dev/null > +++ b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt > @@ -0,0 +1,63 @@ > +Device tree configuration for the I2C controller and busses on the AST24XX > +and AST25XX SoCs. > + > +Controller: > + > + Required Properties: > + - #address-cells : should be 1 > + - #size-cells : should be 1 > + - #interrupt-cells : should be 1 > + - compatible : should be "aspeed,ast2400-i2c-controller" > + or "aspeed,ast2500-i2c-controller" > + - reg : address start and range of controller > + - ranges : defines address offset and range for busses > + - interrupts : interrupt number > + - clocks : root clock of bus, should reference the APB > + clock > + - clock-ranges : specifies that child busses can inherit clocks > + - interrupt-controller : denotes that the controller receives and fires > + new interrupts for child busses > + > +Bus: > + > + Required Properties: > + - #address-cells : should be 1 > + - #size-cells : should be 0 > + - reg : address offset and range of bus > + - compatible : should be "aspeed,ast2400-i2c-bus" > + or "aspeed,ast2500-i2c-bus" > + - bus : the bus's number Don't use indexes. The reg property is enough to id which bus is which. -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Addressed in v3. Thanks! On Mon, Sep 19, 2016 at 2:35 PM, Rob Herring <robh@kernel.org> wrote: > On Fri, Sep 09, 2016 at 06:55:51PM -0700, Brendan Higgins wrote: >> Added device tree binding documentation for Aspeed I2C controller and >> busses. >> >> Signed-off-by: Brendan Higgins <brendanhiggins@google.com> >> --- >> Changes for v2: >> - None >> --- >> .../devicetree/bindings/i2c/i2c-aspeed.txt | 63 ++++++++++++++++++++++ >> 1 file changed, 63 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-aspeed.txt >> >> diff --git a/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt >> new file mode 100644 >> index 0000000..df68f2a >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt >> @@ -0,0 +1,63 @@ >> +Device tree configuration for the I2C controller and busses on the AST24XX >> +and AST25XX SoCs. >> + >> +Controller: >> + >> + Required Properties: >> + - #address-cells : should be 1 >> + - #size-cells : should be 1 >> + - #interrupt-cells : should be 1 >> + - compatible : should be "aspeed,ast2400-i2c-controller" >> + or "aspeed,ast2500-i2c-controller" >> + - reg : address start and range of controller >> + - ranges : defines address offset and range for busses >> + - interrupts : interrupt number >> + - clocks : root clock of bus, should reference the APB >> + clock >> + - clock-ranges : specifies that child busses can inherit clocks >> + - interrupt-controller : denotes that the controller receives and fires >> + new interrupts for child busses >> + >> +Bus: >> + >> + Required Properties: >> + - #address-cells : should be 1 >> + - #size-cells : should be 0 >> + - reg : address offset and range of bus >> + - compatible : should be "aspeed,ast2400-i2c-bus" >> + or "aspeed,ast2500-i2c-bus" >> + - bus : the bus's number > > Don't use indexes. The reg property is enough to id which bus is which. -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
(sorry if you get a duplicate, I forgot to send plain text) First off, someone pointed out to me that the mapping that I used between addresses and bus numbers is not actually valid for busses 8-14. This could be fixed by checking the offset, but I am wondering if that is the right way to do it. It seems like this is not completely trivial so maybe this should be specified in the device tree? If that is the case, should I do this as another reg entry or go back to the way I was doing it before? On Mon, Sep 19, 2016 at 4:26 PM, Brendan Higgins <brendanhiggins@google.com> wrote: > Addressed in v3. > > Thanks! > > On Mon, Sep 19, 2016 at 2:35 PM, Rob Herring <robh@kernel.org> wrote: >> On Fri, Sep 09, 2016 at 06:55:51PM -0700, Brendan Higgins wrote: >>> Added device tree binding documentation for Aspeed I2C controller and >>> busses. >>> >>> Signed-off-by: Brendan Higgins <brendanhiggins@google.com> >>> --- >>> Changes for v2: >>> - None >>> --- >>> .../devicetree/bindings/i2c/i2c-aspeed.txt | 63 ++++++++++++++++++++++ >>> 1 file changed, 63 insertions(+) >>> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-aspeed.txt >>> >>> diff --git a/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt >>> new file mode 100644 >>> index 0000000..df68f2a >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt >>> @@ -0,0 +1,63 @@ >>> +Device tree configuration for the I2C controller and busses on the AST24XX >>> +and AST25XX SoCs. >>> + >>> +Controller: >>> + >>> + Required Properties: >>> + - #address-cells : should be 1 >>> + - #size-cells : should be 1 >>> + - #interrupt-cells : should be 1 >>> + - compatible : should be "aspeed,ast2400-i2c-controller" >>> + or "aspeed,ast2500-i2c-controller" >>> + - reg : address start and range of controller >>> + - ranges : defines address offset and range for busses >>> + - interrupts : interrupt number >>> + - clocks : root clock of bus, should reference the APB >>> + clock >>> + - clock-ranges : specifies that child busses can inherit clocks >>> + - interrupt-controller : denotes that the controller receives and fires >>> + new interrupts for child busses >>> + >>> +Bus: >>> + >>> + Required Properties: >>> + - #address-cells : should be 1 >>> + - #size-cells : should be 0 >>> + - reg : address offset and range of bus >>> + - compatible : should be "aspeed,ast2400-i2c-bus" >>> + or "aspeed,ast2500-i2c-bus" >>> + - bus : the bus's number >> >> Don't use indexes. The reg property is enough to id which bus is which. -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
To be clear, these bus numbers are defined as part of the hardware specification. I am not sure if that was clear before. On Tue, Sep 20, 2016 at 11:08 AM, Brendan Higgins <brendanhiggins@google.com> wrote: > (sorry if you get a duplicate, I forgot to send plain text) > > First off, someone pointed out to me that the mapping that I used > between addresses and bus numbers is not actually valid for busses > 8-14. > > This could be fixed by checking the offset, but I am wondering if that > is the right way to do it. It seems like this is not completely > trivial so maybe this should be specified in the device tree? If that > is the case, should I do this as another reg entry or go back to the > way I was doing it before? > > On Mon, Sep 19, 2016 at 4:26 PM, Brendan Higgins > <brendanhiggins@google.com> wrote: >> Addressed in v3. >> >> Thanks! >> >> On Mon, Sep 19, 2016 at 2:35 PM, Rob Herring <robh@kernel.org> wrote: >>> On Fri, Sep 09, 2016 at 06:55:51PM -0700, Brendan Higgins wrote: >>>> Added device tree binding documentation for Aspeed I2C controller and >>>> busses. >>>> >>>> Signed-off-by: Brendan Higgins <brendanhiggins@google.com> >>>> --- >>>> Changes for v2: >>>> - None >>>> --- >>>> .../devicetree/bindings/i2c/i2c-aspeed.txt | 63 ++++++++++++++++++++++ >>>> 1 file changed, 63 insertions(+) >>>> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-aspeed.txt >>>> >>>> diff --git a/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt >>>> new file mode 100644 >>>> index 0000000..df68f2a >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt >>>> @@ -0,0 +1,63 @@ >>>> +Device tree configuration for the I2C controller and busses on the AST24XX >>>> +and AST25XX SoCs. >>>> + >>>> +Controller: >>>> + >>>> + Required Properties: >>>> + - #address-cells : should be 1 >>>> + - #size-cells : should be 1 >>>> + - #interrupt-cells : should be 1 >>>> + - compatible : should be "aspeed,ast2400-i2c-controller" >>>> + or "aspeed,ast2500-i2c-controller" >>>> + - reg : address start and range of controller >>>> + - ranges : defines address offset and range for busses >>>> + - interrupts : interrupt number >>>> + - clocks : root clock of bus, should reference the APB >>>> + clock >>>> + - clock-ranges : specifies that child busses can inherit clocks >>>> + - interrupt-controller : denotes that the controller receives and fires >>>> + new interrupts for child busses >>>> + >>>> +Bus: >>>> + >>>> + Required Properties: >>>> + - #address-cells : should be 1 >>>> + - #size-cells : should be 0 >>>> + - reg : address offset and range of bus >>>> + - compatible : should be "aspeed,ast2400-i2c-bus" >>>> + or "aspeed,ast2500-i2c-bus" >>>> + - bus : the bus's number >>> >>> Don't use indexes. The reg property is enough to id which bus is which. -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Brendan, On Wed, Sep 21, 2016 at 3:35 AM, Brendan Higgins <brendanhiggins@google.com> wrote: > First off, someone pointed out to me that the mapping that I used between > addresses and bus numbers is not actually valid for busses 8-14. > > This could be fixed by checking the offset, but I am wondering if that is > the right way to do it. It seems like this is not completely trivial so > maybe this should be specified in the device tree? If that is the case, > should I do this as another reg entry or go back to the way I was doing it > before? I don't see an alternative way to derive these numbers. As you mention, the block of SRAM in the middle of the IP screwing up the linear mapping. I suggest going back to what you have in v2, with a mention in the commit message as to why the bus property is necessary. Cheers, Joel -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt new file mode 100644 index 0000000..df68f2a --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt @@ -0,0 +1,63 @@ +Device tree configuration for the I2C controller and busses on the AST24XX +and AST25XX SoCs. + +Controller: + + Required Properties: + - #address-cells : should be 1 + - #size-cells : should be 1 + - #interrupt-cells : should be 1 + - compatible : should be "aspeed,ast2400-i2c-controller" + or "aspeed,ast2500-i2c-controller" + - reg : address start and range of controller + - ranges : defines address offset and range for busses + - interrupts : interrupt number + - clocks : root clock of bus, should reference the APB + clock + - clock-ranges : specifies that child busses can inherit clocks + - interrupt-controller : denotes that the controller receives and fires + new interrupts for child busses + +Bus: + + Required Properties: + - #address-cells : should be 1 + - #size-cells : should be 0 + - reg : address offset and range of bus + - compatible : should be "aspeed,ast2400-i2c-bus" + or "aspeed,ast2500-i2c-bus" + - bus : the bus's number + - interrupts : interrupt number + + Optional Properties: + - clock-frequency : frequency of the bus clock in Hz + defaults to 100 kHz when not specified + +Example: + +i2c: i2c@1e78a000 { + #address-cells = <1>; + #size-cells = <1>; + #interrupt-cells = <1>; + + compatible = "aspeed,ast2400-i2c-controller"; + reg = <0x1e78a000 0x40>; + ranges = <0 0x1e78a000 0x1000>; + interrupts = <12>; + clocks = <&clk_apb>; + clock-ranges; + interrupt-controller; + + i2c0: i2c-bus@40 { + #address-cells = <1>; + #size-cells = <0>; + reg = <0x40 0x40>; + compatible = "aspeed,ast2400-i2c-bus"; + bus = <0>; + clock-frequency = <100000>; + status = "disabled"; + interrupts = <0>; + interrupt-parent = <&i2c>; + }; +}; +
Added device tree binding documentation for Aspeed I2C controller and busses. Signed-off-by: Brendan Higgins <brendanhiggins@google.com> --- Changes for v2: - None --- .../devicetree/bindings/i2c/i2c-aspeed.txt | 63 ++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 Documentation/devicetree/bindings/i2c/i2c-aspeed.txt