Change in coreboot[master]: mb/google/kahlee: Fix grunt I2C rise/fall times

[Justin TerAvest (Code Review)]

Justin TerAvest has uploaded this change for review. ( https://review.coreboot.org/23520

Change subject: mb/google/kahlee: Fix grunt I2C rise/fall times
......................................................................

mb/google/kahlee: Fix grunt I2C rise/fall times

I2C bus rise/fall times were measured as follows. Signals were generated
with:
  - bus 0: manual i2c driver in depthcharge
  - bus 2,3: i2cdetect -r <bus_number>
and then measured manually with an oscilloscope.

BUG=b:72442912

Change-Id: I291e144249271ec34a93417398e54e68b8e21e23
Signed-off-by: Justin TerAvest 
---
M src/mainboard/google/kahlee/variants/grunt/devicetree.cb
1 file changed, 9 insertions(+), 9 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/20/23520/1

diff --git a/src/mainboard/google/kahlee/variants/grunt/devicetree.cb b/src/mainboard/google/kahlee/variants/grunt/devicetree.cb
index 9665a78..7ffc0ac 100644
--- a/src/mainboard/google/kahlee/variants/grunt/devicetree.cb
+++ b/src/mainboard/google/kahlee/variants/grunt/devicetree.cb
@@ -21,11 +21,11 @@
    register "uma_mode" = "UMAMODE_SPECIFIED_SIZE"
    register "uma_size" = "128 * MiB"

-	# TODO(teravest): Fix speeds here.
+	# Enable I2C0 for audio, USB3 hub at 400kHz
    register "i2c[0]" = "{
    	.speed = I2C_SPEED_FAST,
-		.rise_time_ns = 104,
-		.fall_time_ns = 52,
+		.rise_time_ns = 95,
+		.fall_time_ns = 3,
    }"

# Enable I2C1 for H1 at 400kHz
@@ -36,18 +36,18 @@
    	.fall_time_ns = 4,
    }"

-	# TODO(teravest): Fix speeds here.
+	# Enable I2C2 for trackpad, pen at 400kHz
    register "i2c[2]" = "{
    	.speed = I2C_SPEED_FAST,
-		.rise_time_ns = 104,
-		.fall_time_ns = 52,
+		.rise_time_ns = 117,
+		.fall_time_ns = 113,
    }"

-	# TODO(teravest): Fix speeds here.
+	# Enable I2C3 for touchscreen at 400kHz
    register "i2c[3]" = "{
    	.speed = I2C_SPEED_FAST,
-		.rise_time_ns = 104,
-		.fall_time_ns = 52,
+		.rise_time_ns = 82,
+		.fall_time_ns = 67,
    }"

device cpu_cluster 0 on