From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=192.198.163.13 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793811204; b=aGgWlTeP5Wo6PpgUrWVbWw6WwxAE18uzt9EMqxKjYQLWK7/Otdmg3s/vrWy2ygM2ixVJ WSBw41/PaB43qwmhEL8T9ZlxKtyKQ5qxjnN1Cgh8xzCz5UZIn8R1mn1c9iU/CW9SsD8Iy eDi7chsIvMKTsz++3Md4OWHQ57D0W33htSOgWY3qEa/GNvAXvwRq4uuLQIbLS6vO1MzLN nQngXTZ/d1WR8ePhvD/RLhRlUsSTbA4HZBzYA5S9K3FqmonYhjIhOgMTH5i0VefYEWXof 0t9I+IDqCjeaJYtDKclzxpWTk3ej0Ibae/LJS1KxZMmn/5hnbkYMQyeUpWCGqKYVXIA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793811204; h=DMARC-Filter:DKIM-Signature:X-CSE-ConnectionGUID:X-CSE-MsgGUID: X-IronPort-AV:X-IronPort-AV:Received:X-CSE-ConnectionGUID: X-CSE-MsgGUID:X-ExtLoop1:X-IronPort-AV:Received:From:To:Cc:Subject: Date:Message-ID:X-Mailer:MIME-Version:Content-Transfer-Encoding; bh=UQ1bDXYKGYdl2Og2jD+uXrW+t00qIxcQlDDGCIWN6fs=; b=S1KYZiUkTH7XaL356A0H5vH1YWriWbh+6BjviZosrIFuCTZJb9AMYnUkoMrtL89tYSPI p68u/Z6XHtgVX77TifxLK2eb63fRWTgSPWogi0zSfB/sEWjJJsXS+W5HtBJy3YnFOMtL5 qJ6/4KIopg7rIaT4MJVW+Eyf24FWG5wrs71dD6pNsiqrxOKb1kOtTedNOSfFs1MMhHh81 zMWuSBzeTo7ZKJ5pzNsrX5hD72QjoF8oKG5vOEy/N/DW+HlAbrwmtjQ99mvsS6IU6VRDm MoCEqREhWzxPrwegcf1xSe+cR0CWUxQn1ZGw9xYwAA4QSSjz1exZImF2/cNu7zTwZ8g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=NfMVOP+W; arc=none smtp.remote-ip=192.198.163.13 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.13]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EE94C606D83E; Wed, 4 Nov 2026 16:53:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org EE94C606D83E 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, unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=NfMVOP+W DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1793811203; x=1825347203; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=d/n2sCxEobfdrct2quWj6oFiwwBQ5P4rZozc4rIP7Xg=; b=NfMVOP+WDrBJ7nmgbpQG5+3XcEqQ2mdGTwV0zfV8E8NFqwTuT+55sZOi 6DS1AeqcZUhNzUdvhMWdvc5Pw6U9Uk5bjuINrQtSjY86EPHHKTbAzVs10 YRyPP50OT/Tt+FEDJetAzd00RSQopW6hENKVMm9gKcfPt8YOwytin1+eu BAte0R2fgd15ffuubGW9njyokpBO+rgQOjPovNAVC+G/SyFB+Ah5hJ784 SBqx/ClK0M8rfAO/lf48+ijxtSd2BSdrHm5XTlYXYkOVTydV6bp0WzaJX AmEhKWI2LgAI1r011dxO8u/Em9TUOB6LrpIdY98IIm7SeEBEAl5B+Etkx w==; X-CSE-ConnectionGUID: 5L10r3jAR5S44wbh4OdvFw== X-CSE-MsgGUID: oWvfOwmCThaqEtMzB22AVg== X-IronPort-AV: E=McAfee;i="6800,10657,11956"; a="2570439" X-IronPort-AV: E=Sophos;i="6.27,195,1787036400"; d="scan'208";a="2570439" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Nov 2026 08:53:23 -0800 X-CSE-ConnectionGUID: NDo/dX6MRd6MKYnEtEiXrQ== X-CSE-MsgGUID: VEuzpK/CSRGIwueXMXEulg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,195,1787036400"; d="scan'208";a="7087603" Received: from spandruv-desk.jf.intel.com ([10.54.55.20]) by fmviesa008.fm.intel.com with ESMTP; 04 Nov 2026 08:53:23 -0800 From: Srinivas Pandruvada To: jikos@kernel.org, jic23@kernel.org, bentiss@kernel.org Cc: linux-input@vger.kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, simeon@maryasin.name, Srinivas Pandruvada , stable@vger.kernel.org Subject: [PATCH v2] iio: hid-sensors: fix fractional part for unit exponents -7 and -8 Date: Wed, 4 Nov 2026 08:53:19 -0800 Message-ID: <20261104165319.1890851-1-srinivas.pandruvada@linux.intel.com> X-Mailer: git-send-email 2.55.0 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit split_micro_fraction() scales the remainder to micro units by multiplying it by 10^(6 - exp). The unit exponent of a HID field goes down to -8, so exp can be 7 or 8 here. Then the argument of int_pow() is negative, which the unsigned parameter turns into a huge power of ten: 0 modulo 2^64. As a result, the fractional part of a value read from the hysteresis attributes is always reported as 0. Divide by 10^(exp - 6) in these two cases. This matches the reverse conversion in convert_to_vtf_format(). Fixes: 73c6768b710a ("iio: hid-sensors: Common attribute and trigger") Cc: stable@vger.kernel.org Signed-off-by: Srinivas Pandruvada --- v2: - Fix __udivdi3 link error on 32-bit by using a 32-bit divisor - Address Andy's comment: Keep no % divisor in a temporary variable next to no / divisor drivers/iio/common/hid-sensors/hid-sensor-attributes.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c index 9e7c26e37880..d44091faf122 100644 --- a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c +++ b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c @@ -96,9 +96,14 @@ static void simple_div(int dividend, int divisor, int *whole, int *micro_frac) static void split_micro_fraction(unsigned int no, int exp, int *val1, int *val2) { int divisor = int_pow(10, exp); + unsigned int rem; *val1 = no / divisor; - *val2 = no % divisor * int_pow(10, 6 - exp); + rem = no % divisor; + if (exp > 6) + *val2 = rem / (unsigned int)int_pow(10, exp - 6); + else + *val2 = rem * int_pow(10, 6 - exp); } /* -- 2.56.0