diff mbox series

dt-bindings: i2c: Add device clock-stretch time via dts

Message ID 1615622829-15167-1-git-send-email-qii.wang@mediatek.com (mailing list archive)
State New, archived
Headers show
Series dt-bindings: i2c: Add device clock-stretch time via dts | expand

Commit Message

Qii Wang (王琪) March 13, 2021, 8:07 a.m. UTC
From: Qii Wang <qii.wang@mediatek.com>

tSU,STA/tHD,STA/tSU,STOP maybe out of spec due to device
clock-stretching or circuit loss, we could get device
clock-stretch time from dts to adjust these parameters
to meet the spec via EXT_CONF register.

Signed-off-by: Qii Wang <qii.wang@mediatek.com>
---
 Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt | 1 +
 1 file changed, 1 insertion(+)

Comments

Rob Herring (Arm) March 24, 2021, 5:12 p.m. UTC | #1
On Sat, Mar 13, 2021 at 04:07:09PM +0800, qii.wang@mediatek.com wrote:
> From: Qii Wang <qii.wang@mediatek.com>
> 
> tSU,STA/tHD,STA/tSU,STOP maybe out of spec due to device
> clock-stretching or circuit loss, we could get device
> clock-stretch time from dts to adjust these parameters
> to meet the spec via EXT_CONF register.
> 
> Signed-off-by: Qii Wang <qii.wang@mediatek.com>
> ---
>  Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt b/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt
> index 7f0194f..97f66f0 100644
> --- a/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt
> @@ -32,6 +32,7 @@ Optional properties:
>    - mediatek,have-pmic: platform can control i2c form special pmic side.
>      Only mt6589 and mt8135 support this feature.
>    - mediatek,use-push-pull: IO config use push-pull mode.
> +  - clock-stretch-ns: Slave device clock-stretch time.

Should be a common I2C property?

>  
>  Example:
>  
> -- 
> 1.9.1
>
Qii Wang (王琪) March 26, 2021, 1:30 a.m. UTC | #2
On Wed, 2021-03-24 at 11:12 -0600, Rob Herring wrote:
> On Sat, Mar 13, 2021 at 04:07:09PM +0800, qii.wang@mediatek.com wrote:
> > From: Qii Wang <qii.wang@mediatek.com>
> > 
> > tSU,STA/tHD,STA/tSU,STOP maybe out of spec due to device
> > clock-stretching or circuit loss, we could get device
> > clock-stretch time from dts to adjust these parameters
> > to meet the spec via EXT_CONF register.
> > 
> > Signed-off-by: Qii Wang <qii.wang@mediatek.com>
> > ---
> >  Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt b/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt
> > index 7f0194f..97f66f0 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt
> > @@ -32,6 +32,7 @@ Optional properties:
> >    - mediatek,have-pmic: platform can control i2c form special pmic side.
> >      Only mt6589 and mt8135 support this feature.
> >    - mediatek,use-push-pull: IO config use push-pull mode.
> > +  - clock-stretch-ns: Slave device clock-stretch time.
> 
> Should be a common I2C property?
> 

Wolfram Sang will look at this next and think about it. I hope it would
be a common I2C property.

> >  
> >  Example:
> >  
> > -- 
> > 1.9.1
> >
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt b/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt
index 7f0194f..97f66f0 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mt65xx.txt
@@ -32,6 +32,7 @@  Optional properties:
   - mediatek,have-pmic: platform can control i2c form special pmic side.
     Only mt6589 and mt8135 support this feature.
   - mediatek,use-push-pull: IO config use push-pull mode.
+  - clock-stretch-ns: Slave device clock-stretch time.
 
 Example: