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mb/google/dedede/var/sasuke: Configure I2C times for touchpad/audio 

Configure I2C rise/fall time in device tree to ensure I2C CLK runs
accurately at I2C_SPEED_FAST (< 400 kHz).

Measured I2C frequency just as below after tuning:
I2C0(touchpad): 385 kHz
I2C4(audio): 380 kHz

BUG=b:180335053
BRANCH=dedede
TEST=Build and check after tuning I2C clock is under 400kHz

Change-Id: Ic92ee0379456e80260a8026bc38ee41325dad6d2
Signed-off-by: Seunghwan Kim <sh_.kim@samsung.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51335
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
This commit is contained in:
Seunghwan Kim 2021-03-08 17:41:28 +09:00 committed by Karthik Ramasubramanian
parent 66c52ffb2b
commit 6ffaf5a691
1 changed files with 4 additions and 9 deletions
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13
src/mainboard/google/dedede/variants/sasuke/overridetree.cb
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@ -61,9 +61,8 @@ chip soc/intel/jasperlake
}, },
.i2c[0] = { .i2c[0] = {
.speed = I2C_SPEED_FAST, .speed = I2C_SPEED_FAST,
.rise_time_ns = 66, .rise_time_ns = 209,
.fall_time_ns = 90, .fall_time_ns = 12,
.data_hold_time_ns = 350,
}, },
.i2c[1] = { .i2c[1] = {
.speed = I2C_SPEED_FAST, .speed = I2C_SPEED_FAST,
@ -76,12 +75,8 @@ chip soc/intel/jasperlake
}, },
.i2c[4] = { .i2c[4] = {
.speed = I2C_SPEED_FAST, .speed = I2C_SPEED_FAST,
.speed_config[0] = { .rise_time_ns = 175,
.speed = I2C_SPEED_FAST, .fall_time_ns = 8,
.scl_lcnt = 176,
.scl_hcnt = 95,
.sda_hold = 36,
}
}, },
}" }"
device domain 0 on device domain 0 on