From 85a80ef4726a0f088d7d2007553349b861908386 Mon Sep 17 00:00:00 2001 From: Aaron Durbin Date: Thu, 3 Nov 2016 13:34:13 -0500 Subject: reef: tune trackpad i2c frequency to 400kHz This brings the frequency down to 400kHz which is spec for fast i2c. BUG=chrome-os-partner:58889 Change-Id: Ibc5f152e55ed618f18ac6425264f086b1f2d1ffa Signed-off-by: Aaron Durbin Reviewed-on: https://review.coreboot.org/17215 Reviewed-by: Duncan Laurie Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel --- src/mainboard/google/reef/variants/baseboard/devicetree.cb | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/src/mainboard/google/reef/variants/baseboard/devicetree.cb b/src/mainboard/google/reef/variants/baseboard/devicetree.cb index 559b0071be..5aa1d32ec2 100644 --- a/src/mainboard/google/reef/variants/baseboard/devicetree.cb +++ b/src/mainboard/google/reef/variants/baseboard/devicetree.cb @@ -84,6 +84,17 @@ chip soc/intel/apollolake } }" + # Limit trackpad speed to 400kHz with manually tuned values. + register "i2c[4]" = "{ + .speed = I2C_SPEED_FAST, + .speed_config[0] = { + .speed = I2C_SPEED_FAST, + .scl_lcnt = 0xd0, + .scl_hcnt = 0x68, + .sda_hold = 0x27, + } + }" + # Minimum SLP S3 assertion width 28ms. register "slp_s3_assertion_width_usecs" = "28000" -- cgit v1.2.3