Re: [PATCH 1/3] dt-bindings: Add I2C bindings for mt65xx/mt81xx.

Matthias Brugger
2014-10-31T10:50:27Z

2014-10-31 2:38 GMT+01:00 xudong chen <xudong.chen@mediatek.com>:
> On Thu, 2014-10-30 at 13:38 +0100, Matthias Brugger wrote:
>> 2014-10-29 6:37 GMT+01:00 Xudong Chen <xudong.chen@mediatek.com>:
>> > Add devicetree bindings for Mediatek Soc I2C driver.
>> >
>> > Signed-off-by: Xudong Chen <xudong.chen@mediatek.com>
>> > ---
>> > .../devicetree/bindings/i2c/i2c-mt6577.txt | 37 ++++++++++++++++++++++
>> > 1 file changed, 37 insertions(+)
>> > create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
>> >
>> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mt6577.txt b/Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
>> > new file mode 100644
>> > index 0000000..b4012c8
>> > --- /dev/null
>> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
>> > @@ -0,0 +1,37 @@
>> > +* Mediatek's I2C controller
>> > +
>> > +The Mediatek's I2C controller is used to interface with I2C devices.
>> > +
>> > +Required properties:
>> > + - compatible: value should be either of the following.
>> > + (a) "mtk,mt6577-i2c", for i2c compatible with mt6577 i2c.
>>
>> Looking on the datasheet of mt6577 it does not seem that this driver
>> is really compatible.
>> I was not able to find the PATH_DIR register neither in the datasheet
>> nor in the source code.
>>
> Hi,
>
> The PATH_DIR register named OFFSET_PATH_DIR(0x60) in the source code.
> Only MT8135 supports this feature, so it does not contained in mt6577
> datasheet.
> I will modify the comment.
>
>> > + (b) "mtk,mt8127-i2c", for i2c compatible with mt8127 i2c.
>> > + (c) "mtk,mt8135-i2c", for i2c compatible with mt8135 i2c.
>> > + - reg: physical base address of the controller and dma base, length of memory mapped
>> > + region.
>> > + - interrupts: interrupt number to the cpu.
>> > + - clock-div: the fixed value for frequency divider of clock source in i2c module.
>> > + Each IC may be different.
>> > + - clocks: clock name from clock manager
>> > + - clock-names: clock name used in i2c driver probe
>> > +
>> > +Optional properties:
>> > + - clock-frequency: Frequency in Hz of the bus when transfer, the default value is 100000.
>> > + - mediatek,have-pmic: platform can control i2c form special pmic side.
>
> I will change this to:
> - mediatek,have-pmic: platform can control i2c form special pmic side,
> only MT8135 supports this.
>
> Is this OK?

We need a multi function device driver for the I2C and the PMIC.
Please have a look on my comments in the other thread.

Thanks,
Matthias

>
>> > + - mediatek,have-dcm: platform has DCM(hardware digital clock manager) property.
>> > + - mediatek,use-push-pull: IO use push-pull mode.
>> > +
>> > +Example:
>> > +
>> > + i2c0: i2c@1100d000 {
>> > + compatible = "mediatek,mt6577-i2c";
>> > + reg = <0x1100d000 0x70>,
>> > + <0x11000300 0x80>;
>> > + interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_LOW>;
>> > + clock-frequency = <100000>;
>> > + mediatek,have-pmic;
>> > + clock-div = <16>;
>> > + clocks = <&i2c0_ck>, <&ap_dma_ck>;
>> > + clock-names = "main", "dma";
>> > + };
>> > +
>> > --
>> > 1.8.1.1.dirty
>> >
>>
>>
>>
>
>

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