[PATCH-v5 4/5] Documentation: binding: add sclk adjustment properties to i2c-pxa
Vaibhav Hiremath
vaibhav.hiremath at linaro.org
Tue Jul 21 05:41:05 PDT 2015
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 at 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 at 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 at d4025000 {
--
1.9.1
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