From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A22922853FD; Fri, 18 Sep 2026 05:57:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789711022; cv=none; b=db1o7K0S3nIsI3w7CjthYKNsdZJef+hZDZdJiTvHoYOgyWmeEMC+DjG9+0P2DLe5pj7kyH+DLpMzLKU4TVlZyW2OGWRGPWR5vSuq0r902M4kRYP3/FCxjCkq21f+C3jsXEbpu0OyvfdhXzZCMeezYc1YcDU5WA3XukFkFYNszd4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789711022; c=relaxed/simple; bh=Ug1YYs1QoG5a0cLyLRgAfW0LHixvwk05lM/CTrnNHHk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=l4jFWDQaNwJW8nRBbezkEFk3kFQ/TdompJYoyv949b89F6XmhhWZ08sKb1Izi/04hhXbXPGWP4yRwiA7DUwG0rrY+2xrjy5QAF+Wj0O47ItgaA7U64X/SHHPOk4V6aYOrkupF5zMbFZUMlVp5LrH3FYmxZQvJm0PJNswdC6PY2M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=i7bgDJZs; arc=none smtp.client-ip=192.198.163.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="i7bgDJZs" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1789711020; x=1821247020; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=Ug1YYs1QoG5a0cLyLRgAfW0LHixvwk05lM/CTrnNHHk=; b=i7bgDJZsO16TSpV8KQP3gKpnOovYgsBUyRlpLqBWWhAowmjOQZDRF/6t K9VG9bYjquf/9aHeVaQHmsXfmOM88M1CyRoL+Yo1HUo5EKyaiZi5I6e5f luzAaxLwqSbFq1FuFivz44jxGxhErE8rXEaRxyQ+zaNk+7dE+MX15bv9V owBuACV0WZshQgBRMQ0Gll2XSeihX1CEEeaN1+ANy1pk6j1atGK3j/sCg cN1JpNKa0qOYTvLWzcku/bPr/3feH47YA2Al3F7mpsfhc81g1X1QMiWrF beMmOo5paP8L7uO6jwD2kGOMenhmm4uw8hRF/D7YzP1RaEyD9+fFBPAGO A==; X-CSE-ConnectionGUID: WagMAFepQMytKC6pOKfyuw== X-CSE-MsgGUID: kxbWuQRNQY+3fMezksnUMg== X-IronPort-AV: E=McAfee;i="6800,10657,11905"; a="90326751" X-IronPort-AV: E=Sophos;i="6.27,103,1787036400"; d="scan'208";a="90326751" Received: from fmviesa013.fm.intel.com ([10.60.135.153]) by fmvoesa109.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Sep 2026 22:57:00 -0700 X-CSE-ConnectionGUID: U3QRh2jRRqWdopq5s0ua8Q== X-CSE-MsgGUID: 55OnJffxSEancRpCOmUhyw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,103,1787036400"; d="scan'208";a="2629668" Received: from black.igk.intel.com ([10.91.253.5]) by fmviesa013.fm.intel.com with ESMTP; 17 Sep 2026 22:56:59 -0700 Received: by black.igk.intel.com (Postfix, from userid 1001) id 6136D99; Fri, 18 Sep 2026 07:56:53 +0200 (CEST) Date: Fri, 18 Sep 2026 07:56:53 +0200 From: Mika Westerberg To: Yuqi Xu Cc: westeri@kernel.org, andi.shyti@kernel.org, linux-i2c@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] i2c: acpi: Add ELAN0662 to i2c_acpi_force_100khz_device_ids Message-ID: <20260918055653.GD106095@black.igk.intel.com> References: <20260918054109.23550-1-xuyuqiabc@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260918054109.23550-1-xuyuqiabc@gmail.com> On Fri, Sep 18, 2026 at 01:41:09PM +0800, Yuqi Xu wrote: > The ELAN0662 touchpad (04F3:317C) in the Lenovo ThinkBook 14 G4+ ARA > (21D0) intermittently stutters and drops touches. libinput discards > invalid touch coordinates and logs (rate limited to five messages per > 24 hours): > > libinput error: event6 - ELAN0662:00 04F3:317C Touchpad: kernel > bug: Touch jump detected and discarded. > > The ACPI DSDT describes the touchpad's I2cSerialBus resource on an > AMDI0010 controller with a connection speed of 0x00061A80 (400 kHz), > and the kernel does not lower it for this device, so the touchpad runs > at 400 kHz. This is the same issue previously fixed for ELAN06FA and > ELAN0678. > > Forcing the bus to 100 kHz was tested with a DSDT override on the > affected machine, and the kernel confirmed the override: > > ACPI: Table Upgrade: override [DSDT-LENOVO-CB-01] > > Before the change libinput discarded three touch jumps within about a > minute of touchpad use; after the change no touch jumps were logged > during more than an hour of normal use. The patch itself was not build > tested; the behaviour was validated through the ACPI table override > above. > > Assisted-by: DeepSeek:deepseek-v4.1-flash > Signed-off-by: Yuqi Xu Acked-by: Mika Westerberg (Intel)