> -----Original Message----- > From: Rob Herring <robh@xxxxxxxxxx> > Sent: 2019年5月3日 4:59 > To: Chuanhua Han <chuanhua.han@xxxxxxx> > Cc: mark.rutland@xxxxxxx; shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; > Leo Li <leoyang.li@xxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; > devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > linux-i2c@xxxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; dl-linux-imx > <linux-imx@xxxxxxx>; festevam@xxxxxxxxx; > wsa+renesas@xxxxxxxxxxxxxxxxxxxx; u.kleine-koenig@xxxxxxxxxxxxxx; > eha@xxxxxxxx; linux@xxxxxxxxxxxxxxxx; Sumit Batra <sumit.batra@xxxxxxx>; > l.stach@xxxxxxxxxxxxxx; peda@xxxxxxxxxx > Subject: [EXT] Re: [PATCH 1/3] dt-bindings: i2c: add optional mul-value > property to binding > > Caution: EXT Email > > On Tue, Apr 30, 2019 at 12:32:40PM +0800, Chuanhua Han wrote: > > NXP Layerscape SoC have up to three MUL options available for all > > divider values, we choice of MUL determines the internal monitor rate > > of the I2C bus (SCL and SDA signals): > > A lower MUL value results in a higher sampling rate of the I2C signals. > > A higher MUL value results in a lower sampling rate of the I2C signals. > > > > So in Optional properties we added our custom mul-value property in > > the binding to select which mul option for the device tree i2c > > controller node. > > > > Signed-off-by: Chuanhua Han <chuanhua.han@xxxxxxx> > > --- > > Documentation/devicetree/bindings/i2c/i2c-imx.txt | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-imx.txt > > b/Documentation/devicetree/bindings/i2c/i2c-imx.txt > > index b967544590e8..ba8e7b7b3fa8 100644 > > --- a/Documentation/devicetree/bindings/i2c/i2c-imx.txt > > +++ b/Documentation/devicetree/bindings/i2c/i2c-imx.txt > > @@ -18,6 +18,9 @@ Optional properties: > > - sda-gpios: specify the gpio related to SDA pin > > - pinctrl: add extra pinctrl to configure i2c pins to gpio function for i2c > > bus recovery, call it "gpio" state > > +- mul-value: NXP Layerscape SoC have up to three MUL options > > +available for all I2C divider values, it describes which MUL we > > +choose to use for the driver, the values should be 1,2,4. > > Needs a vendor prefix. I don't find 'value' to add anything nor do I understand > what MUL is. Yes,you are right! > > If it is determined by SoC rather than board, then it should perhaps be implied > by compatible. This is determined by the SOC, but it has three options to choose from, so I think it's better to use the optional option instead of compatible > > Rob