From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f175.google.com (mail-pf1-f175.google.com [209.85.210.175]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5A2FA361971 for ; Thu, 27 Aug 2026 07:46:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.175 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787816763; cv=none; b=XlARytIsq+9Yzdq3lJqUvwjMTMkRfgYAbZ4oKPb3r/vJGXO4DpqRse4GDigZDgDyqE9EZ1iWFvimSalbfIRBNeBS64dWYCLYgJi6R83rPsXarTuHhjLdFns6aNdsNm4kALO6vX35R4Y2Sljc2jx5CoHhT8PY+MO95keZUdfw76o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787816763; c=relaxed/simple; bh=Pjvhgu2/AEvgKnflUCPPraKj9JOKej2+U3fUV/BsjuU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=qnz5D33UMxnLQe025v92By5j/GkKTcZRLqL6NZh25VQ+f4m5OXtL548g5QA/XeR8++h+3Fn8uly+kPQCdFPVrOtsEY1TS0s921T7php0vpNlZUgzDoDiIR6fvNSXlDcRYyF5Y87OuEEpTviv1fB23raNUil8MKZ0EuInkvveQjc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=AuoXgVEZ; arc=none smtp.client-ip=209.85.210.175 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="AuoXgVEZ" Received: by mail-pf1-f175.google.com with SMTP id d2e1a72fcca58-84e27035206so99284b3a.3 for ; Thu, 27 Aug 2026 00:46:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1787816760; x=1788421560; darn=vger.kernel.org; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to :content-type; bh=LbRs574snZvpW2X/HQOkQ+OUsJHTgB/OYJACP1nJVIU=; b=AuoXgVEZ/M55/kMohZOzkYGfpVdnkPFazAbo8t81J18OKUbh8/Nen8HKdeG2eiXGAw 4o9Y/XgnP5453MfFoJPiooJAz0vNfFaj1ckf/T16RJX7AHsSscDGPC0L88X2NyOkSM4L uo65/QBTzYXeAktzxbOAeZ5PsljFikrDhK3yHfo5h07c17snqEUAwNnXmHhj/32tTrRf qQx/s/We5Fmn7WLUrAlYxnDSfz4XmWy9VI5ELG1NMpbp6cds+xwyxhSp+ZFZuI9fx2jR p6/TMqnh1Hjy4Db0/dPYnwknAIszOoZXJ9F1qjsk1BgmyjOztmt8eiLGPqd7iyZUmcEF GHKQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787816760; x=1788421560; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=LbRs574snZvpW2X/HQOkQ+OUsJHTgB/OYJACP1nJVIU=; b=iBYBm8P9qb3SQljDc2O0IF9Vbe8oj964tt9yxHICC2mibXM+TKxkOH3uCS3iFKdY3K flz7x0lvVje4FfRt9kPD/YJzRbzzFUu9KFY5bQArsZMU1VDx1mnkYIDF7oeEduE9ewFz 04DAfL+ZEJ+L5mG3zsbXsizvf97MqmEPEz8xXmi3VQgKI4Tyn2l4eP5cYxOzJTPm3i0u IE67ULNqSoAdBy+qY+AshnUj26+B84hd5cXlK/S/3Bv4SWxVMj4kueADAqBmeluCOqgO ebAy94qBgQ+//nBYNco+CbohAJSEuDfBwpvmcQmtpvIZPwpeEmDMGN344/DsIT/fHTSa QnTA== X-Forwarded-Encrypted: i=1; AHgh+RpvMMwQg1DcB3bg8mGftMbplh1LvgKJy2/JWodeRr2wOHoisqyH4n37bRQ7S+bn8XdjMAURM7r5xoeH@vger.kernel.org X-Gm-Message-State: AFuF++mDvNj6HTtrbk6hLB0Sj7chNr/rRPfycccNJC/zc8fFeE5cOc58 8yHZsdHEFapW9sIaELD7vCkBhLocbp2F0b5M00Rz0U30Q17MGy9Q7iov X-Gm-Gg: AR+sD13Z6iK79CXK2rgA6mBo0t8NbsjBKlaBx7IbQuCswkCmJZvuVrY3NQsoEIFiNre KsLnbSRn6CPmtTQFdIGhxM/mZuqhvJW4hdcNJdeZNwuhAzxb9PxEkpqRupoEVXBt/DSeDazDMdR Y0ZlzFnrjxbkcnFiobavZl6SCU4qtfDnHuVNim3kCgnzoipU4Qd4pHMrDAQGGvjZOib/EMwrQdR vv3XM/GeHzWUEtjdmwhLVc4dgKfvgPnJWj3SpFLVRA40o75zH7hRQVQnWKYH6LlQOEI4ttdrfPt amFimBT6TsDL2xVZzppPSyobQGuOCQ3bWqRy0FetGNt6ci/ZxRXZF0H30AVO1CNF+sVhQjNPagI Hji5XdpwSsJ+rwxWjVmjsk9NXODQURI27Ks8y2lTW2yBFwr2QDvivuJdt0DDcxKWcrJzHrJyQ+Q e1xcMRD88HzSCvOINZ3ESpp8bJ96yTxqbJFDTKeKnrFF7rB0mFdOGGx6sLmXuJ2A== X-Received: by 2002:a05:6a00:8d0:b0:84e:2722:5d9e with SMTP id d2e1a72fcca58-85371cb27e1mr24732639b3a.1.1787816760362; Thu, 27 Aug 2026 00:46:00 -0700 (PDT) Received: from [198.18.0.1] ([23.26.139.2]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-8535cd7c162sm1680320b3a.33.2026.08.27.00.45.57 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 27 Aug 2026 00:45:59 -0700 (PDT) Message-ID: <11e2734c-2856-4fc2-8209-7410571dbbbf@gmail.com> Date: Thu, 27 Aug 2026 15:46:00 +0800 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] i2c: acpi: Add DELL0A86 to i2c_acpi_force_100khz_device_ids To: Andy Shevchenko , Mika Westerberg Cc: andi.shyti@kernel.org, westeri@kernel.org, linux-i2c@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org References: <63cb7f6e-27ab-43d8-adb5-d2f4acd57674@gmail.com> <20260823123310.188189-1-xiaoyueyoqwq@gmail.com> <20260824102221.GE893316@black.igk.intel.com> Content-Language: en-US From: xiaoyueyoqwq In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi Andy, Sure. The relevant DSDT excerpt is below.     Scope (_SB.PC00.I2C1)     {         ...         Device (TPD0)         {             Name (SBFB, ResourceTemplate ()             {                 I2cSerialBusV2 (0x002C, ControllerInitiated, 0x00061A80,                     AddressingMode7Bit, "\\_SB.PC00.I2C1",                     0x00, ResourceConsumer, _Y55, Exclusive,                     )             })             CreateWordField (SBFB, \_SB.PC00.I2C1.TPD0._Y55._ADR, BADR)             CreateDWordField (SBFB, \_SB.PC00.I2C1.TPD0._Y55._SPE, SPED)             Method (_INI, 0, NotSerialized)             {                 ...                 HID2 = TPDH                 BADR = TPDB                 If ((TPDS == Zero))                 {                     SPED = 0x000186A0                 }                 If ((TPDS == One))                 {                     SPED = 0x00061A80                 }                 If ((TPDS == 0x02))                 {                     SPED = 0x000F4240                 }             }             Name (ITPN, "DELL0A86")             Method (_HID, 0, NotSerialized)             {                 Return (ITPN)             }             ...             Method (_CRS, 0, NotSerialized)             {                 ...                 If ((TPDM == Zero))                 {                     Return (ConcatenateResTemplate (I2CM (I2CX, BADR, SPED), SBFG))                 }                 Return (ConcatenateResTemplate (I2CM (I2CX, BADR, SPED), SBFI))             }         }     } The speed values are 100 kHz, 400 kHz and 1 MHz respectively. On this machine Linux receives 400 kHz from ACPI, which is also confirmed by the kernel log when the quirk is applied:     DSDT uses known not-working I2C bus speed 400000, forcing it to 100000 And for now my PC touchpad has continued to work normally since applying the quirk, and the issue has still not recurred. :) Thanks, YuXin 在 2026/8/27 14:22, Andy Shevchenko 写道: > On Mon, Aug 24, 2026 at 12:22:21PM +0200, Mika Westerberg wrote: >> +Andy >> >> On Sun, Aug 23, 2026 at 08:33:10PM +0800, xiaoyueyoqwq wrote: >>> The ELAN 04F3:3185 touchpad exposed as DELL0A86 on the Dell Inspiron >>> 13 5310 intermittently exhibits excessive smoothing when the I2C bus >>> runs at 400 kHz. During an affected period pointer movement becomes >>> severely sluggish and sticky for tens of seconds. > Just for the confirmation (no need to include in the commit message) can > you share the DSDT excerpt of the device in question? > > (acpidump -o tables.dat; acpixtract tables.dat; iasl -d dsdt.dat; # open dsdt.dsl) > >>> The ACPI firmware configures the touchpad bus for 400 kHz. Add DELL0A86 >>> to i2c_acpi_force_100khz_device_ids so that the bus runs at 100 kHz, as >>> is already done for other touchpads exhibiting the same excessive >>> smoothing problem. >>> >>> With the quirk applied, the kernel reports that the firmware requested >>> 400 kHz and that the bus is forced to 100 kHz. The problem did not recur >>> during extended heavy use, including an S4 hibernate/resume cycle. > ... > >>> + { "DELL0A86", 0 }, >>> { "DLL0945", 0 }, >>> { "ELAN0678", 0 }, >>> { "ELAN06FA", 0 }, > At some point this should be switched to C99 initialisers and dropped unused > driver_data. >