[coreboot-gerrit] Change in coreboot[master]: google/eve: Update I2C bus timing

[Duncan Laurie (Code Review)]

Duncan Laurie has uploaded a new change for review. ( https://review.coreboot.org/19202 )

Change subject: google/eve: Update I2C bus timing
......................................................................

google/eve: Update I2C bus timing

Update the I2C rise/fall timings based on newly measured values
on a new board with updated pull-up resistor values.

Touchscreen: rise time 98ns, fall time 38ms
Touchpad: rise time 111ns, fall time 41ns
TPM: rise time 112ns, fall time 34ns

BUG=b:35583133
BRANCH=none
TEST=Each I2C bus frequency was verified on a scope to be ~400MHz

Change-Id: Ibb3a15fa0cc862f36c1b9c63ac7847221020c4c0
Signed-off-by: Duncan Laurie <dlaurie at chromium.org>
---
M src/mainboard/google/eve/devicetree.cb
1 file changed, 5 insertions(+), 5 deletions(-)


  git pull ssh://review.coreboot.org:29418/coreboot refs/changes/02/19202/1

diff --git a/src/mainboard/google/eve/devicetree.cb b/src/mainboard/google/eve/devicetree.cb
index d8f6362..427ba6b 100644
--- a/src/mainboard/google/eve/devicetree.cb
+++ b/src/mainboard/google/eve/devicetree.cb
@@ -163,7 +163,7 @@
 	register "i2c_voltage[0]" = "I2C_VOLTAGE_3V3"
 	register "i2c[0]" = "{
 		.speed = I2C_SPEED_FAST_PLUS,
-		.rise_time_ns = 17,
+		.rise_time_ns = 98,
 		.fall_time_ns = 38,
 	}"
 
@@ -172,16 +172,16 @@
 	register "i2c[1]" = "{
 		.early_init = 1,
 		.speed = I2C_SPEED_FAST,
-		.rise_time_ns = 88,
-		.fall_time_ns = 32,
+		.rise_time_ns = 112,
+		.fall_time_ns = 34,
 	}"
 
 	# Touchpad
 	register "i2c_voltage[2]" = "I2C_VOLTAGE_1V8"
 	register "i2c[2]" = "{
 		.speed = I2C_SPEED_FAST,
-		.rise_time_ns = 247,
-		.fall_time_ns = 17,
+		.rise_time_ns = 111,
+		.fall_time_ns = 41,
 	}"
 
 	# Audio

-- 
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Gerrit-MessageType: newchange
Gerrit-Change-Id: Ibb3a15fa0cc862f36c1b9c63ac7847221020c4c0
Gerrit-PatchSet: 1
Gerrit-Project: coreboot
Gerrit-Branch: master
Gerrit-Owner: Duncan Laurie <dlaurie at chromium.org>