| Message ID | 1437482466-16126-5-git-send-email-vaibhav.hiremath@linaro.org |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Tue, Jul 21, 2015 at 06:11:05PM +0530, Vaibhav Hiremath wrote: > With addition of PXA910 family of devices, the TWSI module supports > new feature which allows us to adjust SCLK. i2c-pxa driver takes input > configuration in nsec and converts it to respective bit-fields, > > - i2c-sclk-low-time-ns : SCLK low time (tlow) > This property is used along with mode selection. > - i2c-sclk-high-time-ns : SCLK high time (thigh) > - i2c-start-hold-time-ns : Used in case of high speed mode for start bit > hold/setup wait counter. > - i2c-stop-hold-time-ns : Used in case of high speed mode for stop bit > hold/setup wait counter. > - i2c-sda-hold-time-ns : Used to calculate hold/setup wait counter for > standard and fast mode. Again, these should have a mrvl prefix..very specific to this PXA controller. -Matt > Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org> > --- > Documentation/devicetree/bindings/i2c/i2c-pxa.txt | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-pxa.txt b/Documentation/devicetree/bindings/i2c/i2c-pxa.txt > index 9657db5..bb4df60 100644 > --- a/Documentation/devicetree/bindings/i2c/i2c-pxa.txt > +++ b/Documentation/devicetree/bindings/i2c/i2c-pxa.txt > @@ -23,12 +23,25 @@ Optional properties : > - i2c-disable-after-xfer : If set, driver will disable I2C module > after msg xfer and enable it again before xfer. > > + (Applicable to PXA910 family): > + > + - i2c-sclk-low-time-ns : SCLK low time (tlow), for standard/fast/high > + speed mode. > + This property is used along with mode selection. Driver uses this property > + to set low/high time for standard and fast speed mode, as HW counter > + bit-field is same for both. > + - i2c-sclk-high-time-ns : SCLK high time (thigh), Used in case of high speed > + mode only. > + > Examples: > twsi1: i2c@d4011000 { > compatible = "mrvl,mmp-twsi"; > reg = <0xd4011000 0x1000>; > interrupts = <7>; > mrvl,i2c-fast-mode; > + > + i2c-sclk-low-time-ns = <988>; > + i2c-sclk-high-time-ns = <988>; > }; > > twsi2: i2c@d4025000 { > -- > 1.9.1 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- 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
On Monday 27 July 2015 07:41 PM, Matt Porter wrote: > On Tue, Jul 21, 2015 at 06:11:05PM +0530, Vaibhav Hiremath wrote: >> With addition of PXA910 family of devices, the TWSI module supports >> new feature which allows us to adjust SCLK. i2c-pxa driver takes input >> configuration in nsec and converts it to respective bit-fields, >> >> - i2c-sclk-low-time-ns : SCLK low time (tlow) >> This property is used along with mode selection. >> - i2c-sclk-high-time-ns : SCLK high time (thigh) >> - i2c-start-hold-time-ns : Used in case of high speed mode for start bit >> hold/setup wait counter. >> - i2c-stop-hold-time-ns : Used in case of high speed mode for stop bit >> hold/setup wait counter. >> - i2c-sda-hold-time-ns : Used to calculate hold/setup wait counter for >> standard and fast mode. > > Again, these should have a mrvl prefix..very specific to this PXA > controller. > Sorry for delayed response, was down with health issue for week. Coming back to your comment, No, they are not Marvell specific. If you refer back to my V1, we discussed about it and concluded that we should use generic property here. There are quite a few drivers using same properties for similar purpose. Thanks, Vaibhav -- 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
diff --git a/Documentation/devicetree/bindings/i2c/i2c-pxa.txt b/Documentation/devicetree/bindings/i2c/i2c-pxa.txt index 9657db5..bb4df60 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-pxa.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-pxa.txt @@ -23,12 +23,25 @@ Optional properties : - i2c-disable-after-xfer : If set, driver will disable I2C module after msg xfer and enable it again before xfer. + (Applicable to PXA910 family): + + - i2c-sclk-low-time-ns : SCLK low time (tlow), for standard/fast/high + speed mode. + This property is used along with mode selection. Driver uses this property + to set low/high time for standard and fast speed mode, as HW counter + bit-field is same for both. + - i2c-sclk-high-time-ns : SCLK high time (thigh), Used in case of high speed + mode only. + Examples: twsi1: i2c@d4011000 { compatible = "mrvl,mmp-twsi"; reg = <0xd4011000 0x1000>; interrupts = <7>; mrvl,i2c-fast-mode; + + i2c-sclk-low-time-ns = <988>; + i2c-sclk-high-time-ns = <988>; }; twsi2: i2c@d4025000 {
With addition of PXA910 family of devices, the TWSI module supports new feature which allows us to adjust SCLK. i2c-pxa driver takes input configuration in nsec and converts it to respective bit-fields, - i2c-sclk-low-time-ns : SCLK low time (tlow) This property is used along with mode selection. - i2c-sclk-high-time-ns : SCLK high time (thigh) - i2c-start-hold-time-ns : Used in case of high speed mode for start bit hold/setup wait counter. - i2c-stop-hold-time-ns : Used in case of high speed mode for stop bit hold/setup wait counter. - i2c-sda-hold-time-ns : Used to calculate hold/setup wait counter for standard and fast mode. Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org> --- Documentation/devicetree/bindings/i2c/i2c-pxa.txt | 13 +++++++++++++ 1 file changed, 13 insertions(+)