Messages in this thread | | | Date | Wed, 20 Aug 2014 10:34:59 +0100 | From | Mark Rutland <> | Subject | Re: [PATCH 1/2] i2c: designware: device tree bindings for i2c speed mode |
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On Tue, Aug 19, 2014 at 07:34:35PM +0100, atull@opensource.altera.com wrote: > From: Alan Tull <atull@opensource.altera.com> > > Add "speed-mode" Device Tree property to select between > standard and fast i2c mode. Previously, driver was hardwired > as fast mode. Default to fast mode if property is not > present. > > Signed-off-by: Alan Tull <atull@opensource.altera.com> > --- > .../devicetree/bindings/i2c/i2c-designware.txt | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > index 5199b0c..0e4cd21 100644 > --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt > +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt > @@ -9,6 +9,8 @@ Required properties : > Recommended properties : > > - clock-frequency : desired I2C bus clock frequency in Hz. > + - speed-mode : 0 = standard (0 - 100Kb/s) > + : 1 = fast (<= 400Kb/s) <== default
This is a bit opaque.
Is this a limit on the max bit-rate the device should operate at?
Why not just have an optional boolean property to limit to standard speed?
Thanks, Mark.
> > Optional properties : > - i2c-sda-hold-time-ns : should contain the SDA hold time in nanoseconds. > @@ -29,6 +31,7 @@ Example : > reg = <0xf0000 0x1000>; > interrupts = <11>; > clock-frequency = <400000>; > + speed-mode = <0>; > }; > > i2c@1120000 { > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe devicetree" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
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