Commit 9998e388 authored by Niels Franke's avatar Niels Franke Committed by Wolfram Sang
Browse files

i2c: acpi: Add ELAN0678 to i2c_acpi_force_100khz_device_ids 



The ELAN0678 touchpad (04F3:3195) found in the Lenovo ThinkPad X13
exhibits excessive smoothing when the I2C bus runs at 400KHz, making
the touchpad feel sluggish when plugged into AC power. This is the
same issue previously fixed for ELAN06FA.

The device's ACPI table (Lenovo TP-R22) specifies 0x00061A80 (400KHz)
for the I2cSerialBusV2 descriptor. Forcing the bus to 100KHz eliminates
the sluggish behavior.

Signed-off-by: default avatarNiels Franke <nielsfranke@gmail.com>
Acked-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
[wsa: kept the sorting]
Signed-off-by: default avatarWolfram Sang <wsa+renesas@sang-engineering.com>
parent c5f25f58

drivers/i2c/i2c-core-acpi.c

+1 −0
Original line number Diff line number Diff line
@@ -371,6 +371,7 @@ static const struct acpi_device_id i2c_acpi_force_100khz_device_ids[] = { 
	 * a 400KHz frequency. The root cause of the issue is not known.

	 */

	{ "DLL0945", 0 },

	{ "ELAN0678", 0 },

	{ "ELAN06FA", 0 },

	{}

};