From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f176.google.com (mail-pl1-f176.google.com [209.85.214.176]) (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 938511E495; Tue, 14 Jan 2025 19:23:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736882604; cv=none; b=R3o1PzU4JZv1EE+W40Ai+b0fZZh2uHNy9z+lfrofLGISpt0j/HVu+gCubwNOU49/qxK2BoSCSAkEs0ytXqcBdRVyYSkVEZrpn+tJSeFPSG30F9B/FKcxjRvGt/CaWJF2rrlzAqW3vEyYIP4bXVJcXPEHLlGpJ1vWzfEppXF/E5M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736882604; c=relaxed/simple; bh=t0VQ1eoai5qNy82QOQOAGevXVDWMM9LWbTC/bS5u0MY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=dOgFGCNGeJ3AGuXXSeEOcvlhB0NMCPdaRbXF2gEgc1pQeNOMdG5XTXpHKJy5gJc4oyOdpk3rnfsQQOK5HSP23YH8nEJXqUWjG5an9YdV5WnpzFT9MPONu1X95oj1dV8MRvdMSsKtzz4fO+j1a4VQlu0gGIx1msp4ehmjh1CxWJw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=roeck-us.net; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=lltSmTpr; arc=none smtp.client-ip=209.85.214.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=roeck-us.net 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="lltSmTpr" Received: by mail-pl1-f176.google.com with SMTP id d9443c01a7336-2164b1f05caso105041095ad.3; Tue, 14 Jan 2025 11:23:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1736882602; x=1737487402; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:sender:from:to:cc:subject:date:message-id:reply-to; bh=lcM2DfNt6fj4YEk1trckR0yxNSL9PGafmEXu+/w45go=; b=lltSmTprxpASMV59ukUt/DtevxHod1uMZ9ObjZVLig/Q8fPWWlty3B0y4gd16vbm59 0rXBL67ELAWkTGre/Ovh6bqK6jLZj0O+3VHoGLNxMQXpgap5+PYqZpjFUX8r036ZYVah VV6RpUf2Ixn11Bj1z6RGIlSlvdKR2s36gmh6ask40pUwyY77ZGjXm7OzSuQ24Mi6eXUA 1/nkITvWqB7VeEKHiB4YOaueuLV0V6SVsNf0ieVdWU2C9o+gpLenYksKWn2tfECNSVKV QqeXAfbS2HbWqSSV1C97YD0Bw4bxM+Pc3BCdhWYz+oWMGC8LNTSfHsBgjuSeiezDZKZ+ 6twA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736882602; x=1737487402; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:sender:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=lcM2DfNt6fj4YEk1trckR0yxNSL9PGafmEXu+/w45go=; b=UFv+LCB6GdjjjPxdrGSj5GLav8J/YkS3EICNmdLM0ICcYVE6mT1zIqhifWgGpLbduB IRH3UkxPp6C7MvJuI5izIvEEE6Nzy9A/e3nxXcpMkSSmvANE7QhqWLakewn1vVaj/QqX Hpwq56SHX6lo+G18SonbWoulG/H7ptz3FXKkupxf6r2LdiEJYOffCb7qqQSK1Z1JH5EC Bw3nADLiNu7cJR5lCzNAMiuab6xjQLDirI4qvsW6MFE0ncX3JpGa4XzqS4LsSoOgm4Hs GDO4vd9aCggp5ON8ad4AjZIH+tXKrwLH3s4tHWutuXzGU9R377mIsJsD8ROXHHJs1ZIC PUMw== X-Forwarded-Encrypted: i=1; AJvYcCUEBAw6TFnQuCwIgUhZR9jZvFqNcHLuNesENC+w1fhIAoDE6vM0ebo5ArPweIGcDnWkxdj/SxHhwLk9@vger.kernel.org, AJvYcCVjnflCwKlPOEI+uMWYjmv7APHf8OJ2B5vzlc/Z0by2tjJGSeb7KtgeTrFOAQziRb0V9qczWK1QVEYxv+A=@vger.kernel.org, AJvYcCW3Let2VcuOSa6YP0yOMCD3oTLBrGZCLqo50OnwvZxZxtMJEahuU3k/H+Xk33FkZPeP/mg+xrGs8XFW@vger.kernel.org, AJvYcCX5MYMK4ifV76Z4ygu3rq5cXn8sGcwXear/DAdSaVE/ubn+o5XkAmCig7Y/jC9UysdoNqJopATeq4e/Lvi0@vger.kernel.org X-Gm-Message-State: AOJu0Yy/uZ4pE7m5r7xCvwiKEGxWPPbD1+fwr6s2m4nYMitK7QpyMW2E WswzfuQ6Qmq74uPHXrnFA2kpw5Cvk7RLkQvORytyI9P9VfyswePi X-Gm-Gg: ASbGncsDG9ts7GuDuJDQQHBh6y1Ix2RZG3YdlqxwGxBPlvmgaAkpzFwyajhzjfvABTC GWG/p+bXks4kGo3txaWNzJFx2I6w9Y2j24K59ZYd+eDjdwfCJWDPR10rTyt3r/CaL30QaipLLjr SgNVjtVB5IIIyP7CmULmzPqgPCF29Mc7dct2tD5s7ZdBpvuA5py3/IhzTM1jZioqSz2fIn3xgP0 djpjyHAryHgZLfscAS2V+RmQjRvbplAzVVKEguixt+X9fKarvZ/EYD7XzNHyEMGhvWyBgrf2hVt SI5bePEoSFZrFQYgjY3ncygji5rRRA== X-Google-Smtp-Source: AGHT+IGmVTsqntCrUPy37LYagCValfswWYy49esFXnGkoEEirssEhvy87/YDJQso4ywVgxgXdjwx5g== X-Received: by 2002:a17:903:1112:b0:216:138a:5956 with SMTP id d9443c01a7336-21a83f59822mr413267375ad.19.1736882601976; Tue, 14 Jan 2025 11:23:21 -0800 (PST) Received: from ?IPV6:2600:1700:e321:62f0:da43:aeff:fecc:bfd5? ([2600:1700:e321:62f0:da43:aeff:fecc:bfd5]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-a31d5047e01sm8589088a12.54.2025.01.14.11.23.20 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 14 Jan 2025 11:23:21 -0800 (PST) Sender: Guenter Roeck Message-ID: Date: Tue, 14 Jan 2025 11:23:19 -0800 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/2] hwmon: Add driver for TI INA232 Current and Power Monitor To: Leo Yang Cc: jdelvare@suse.com, robh@kernel.org, davem@davemloft.net, krzk+dt@kernel.org, conor+dt@kernel.org, Leo-Yang@quantatw.com, corbet@lwn.net, Delphine_CC_Chiu@wiwynn.com, linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kernel test robot References: <20250110081546.61667-1-Leo-Yang@quantatw.com> <20250110081546.61667-3-Leo-Yang@quantatw.com> <190bb6f2-7bbe-4145-b45f-4ad6672884b8@roeck-us.net> Content-Language: en-US From: Guenter Roeck Autocrypt: addr=linux@roeck-us.net; keydata= xsFNBE6H1WcBEACu6jIcw5kZ5dGeJ7E7B2uweQR/4FGxH10/H1O1+ApmcQ9i87XdZQiB9cpN RYHA7RCEK2dh6dDccykQk3bC90xXMPg+O3R+C/SkwcnUak1UZaeK/SwQbq/t0tkMzYDRxfJ7 nyFiKxUehbNF3r9qlJgPqONwX5vJy4/GvDHdddSCxV41P/ejsZ8PykxyJs98UWhF54tGRWFl 7i1xvaDB9lN5WTLRKSO7wICuLiSz5WZHXMkyF4d+/O5ll7yz/o/JxK5vO/sduYDIlFTvBZDh gzaEtNf5tQjsjG4io8E0Yq0ViobLkS2RTNZT8ICq/Jmvl0SpbHRvYwa2DhNsK0YjHFQBB0FX IdhdUEzNefcNcYvqigJpdICoP2e4yJSyflHFO4dr0OrdnGLe1Zi/8Xo/2+M1dSSEt196rXaC kwu2KgIgmkRBb3cp2vIBBIIowU8W3qC1+w+RdMUrZxKGWJ3juwcgveJlzMpMZNyM1jobSXZ0 VHGMNJ3MwXlrEFPXaYJgibcg6brM6wGfX/LBvc/haWw4yO24lT5eitm4UBdIy9pKkKmHHh7s jfZJkB5fWKVdoCv/omy6UyH6ykLOPFugl+hVL2Prf8xrXuZe1CMS7ID9Lc8FaL1ROIN/W8Vk BIsJMaWOhks//7d92Uf3EArDlDShwR2+D+AMon8NULuLBHiEUQARAQABzTJHdWVudGVyIFJv ZWNrIChMaW51eCBhY2NvdW50KSA8bGludXhAcm9lY2stdXMubmV0PsLBgQQTAQIAKwIbAwYL CQgHAwIGFQgCCQoLBBYCAwECHgECF4ACGQEFAlVcphcFCRmg06EACgkQyx8mb86fmYFg0RAA nzXJzuPkLJaOmSIzPAqqnutACchT/meCOgMEpS5oLf6xn5ySZkl23OxuhpMZTVX+49c9pvBx hpvl5bCWFu5qC1jC2eWRYU+aZZE4sxMaAGeWenQJsiG9lP8wkfCJP3ockNu0ZXXAXwIbY1O1 c+l11zQkZw89zNgWgKobKzrDMBFOYtAh0pAInZ9TSn7oA4Ctejouo5wUugmk8MrDtUVXmEA9 7f9fgKYSwl/H7dfKKsS1bDOpyJlqhEAH94BHJdK/b1tzwJCFAXFhMlmlbYEk8kWjcxQgDWMu GAthQzSuAyhqyZwFcOlMCNbAcTSQawSo3B9yM9mHJne5RrAbVz4TWLnEaX8gA5xK3uCNCeyI sqYuzA4OzcMwnnTASvzsGZoYHTFP3DQwf2nzxD6yBGCfwNGIYfS0i8YN8XcBgEcDFMWpOQhT Pu3HeztMnF3HXrc0t7e5rDW9zCh3k2PA6D2NV4fews9KDFhLlTfCVzf0PS1dRVVWM+4jVl6l HRIAgWp+2/f8dx5vPc4Ycp4IsZN0l1h9uT7qm1KTwz+sSl1zOqKD/BpfGNZfLRRxrXthvvY8 BltcuZ4+PGFTcRkMytUbMDFMF9Cjd2W9dXD35PEtvj8wnEyzIos8bbgtLrGTv/SYhmPpahJA l8hPhYvmAvpOmusUUyB30StsHIU2LLccUPPOwU0ETofVZwEQALlLbQeBDTDbwQYrj0gbx3bq 7kpKABxN2MqeuqGr02DpS9883d/t7ontxasXoEz2GTioevvRmllJlPQERVxM8gQoNg22twF7 pB/zsrIjxkE9heE4wYfN1AyzT+AxgYN6f8hVQ7Nrc9XgZZe+8IkuW/Nf64KzNJXnSH4u6nJM J2+Dt274YoFcXR1nG76Q259mKwzbCukKbd6piL+VsT/qBrLhZe9Ivbjq5WMdkQKnP7gYKCAi pNVJC4enWfivZsYupMd9qn7Uv/oCZDYoBTdMSBUblaLMwlcjnPpOYK5rfHvC4opxl+P/Vzyz 6WC2TLkPtKvYvXmdsI6rnEI4Uucg0Au/Ulg7aqqKhzGPIbVaL+U0Wk82nz6hz+WP2ggTrY1w ZlPlRt8WM9w6WfLf2j+PuGklj37m+KvaOEfLsF1v464dSpy1tQVHhhp8LFTxh/6RWkRIR2uF I4v3Xu/k5D0LhaZHpQ4C+xKsQxpTGuYh2tnRaRL14YMW1dlI3HfeB2gj7Yc8XdHh9vkpPyuT nY/ZsFbnvBtiw7GchKKri2gDhRb2QNNDyBnQn5mRFw7CyuFclAksOdV/sdpQnYlYcRQWOUGY HhQ5eqTRZjm9z+qQe/T0HQpmiPTqQcIaG/edgKVTUjITfA7AJMKLQHgp04Vylb+G6jocnQQX JqvvP09whbqrABEBAAHCwWUEGAECAA8CGwwFAlVcpi8FCRmg08MACgkQyx8mb86fmYHNRQ/+ J0OZsBYP4leJvQF8lx9zif+v4ZY/6C9tTcUv/KNAE5leyrD4IKbnV4PnbrVhjq861it/zRQW cFpWQszZyWRwNPWUUz7ejmm9lAwPbr8xWT4qMSA43VKQ7ZCeTQJ4TC8kjqtcbw41SjkjrcTG wF52zFO4bOWyovVAPncvV9eGA/vtnd3xEZXQiSt91kBSqK28yjxAqK/c3G6i7IX2rg6pzgqh hiH3/1qM2M/LSuqAv0Rwrt/k+pZXE+B4Ud42hwmMr0TfhNxG+X7YKvjKC+SjPjqp0CaztQ0H nsDLSLElVROxCd9m8CAUuHplgmR3seYCOrT4jriMFBtKNPtj2EE4DNV4s7k0Zy+6iRQ8G8ng QjsSqYJx8iAR8JRB7Gm2rQOMv8lSRdjva++GT0VLXtHULdlzg8VjDnFZ3lfz5PWEOeIMk7Rj trjv82EZtrhLuLjHRCaG50OOm0hwPSk1J64R8O3HjSLdertmw7eyAYOo4RuWJguYMg5DRnBk WkRwrSuCn7UG+qVWZeKEsFKFOkynOs3pVbcbq1pxbhk3TRWCGRU5JolI4ohy/7JV1TVbjiDI HP/aVnm6NC8of26P40Pg8EdAhajZnHHjA7FrJXsy3cyIGqvg9os4rNkUWmrCfLLsZDHD8FnU mDW4+i+XlNFUPUYMrIKi9joBhu18ssf5i5Q= In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 1/14/25 00:02, Leo Yang wrote: > Hi Guenter, > > On Sat, Jan 11, 2025 at 12:22 AM Guenter Roeck wrote: >> >>> + >>> + /* If INA233 skips current/power, shunt-resistor and current-lsb aren't needed. */ >>> + /* read rshunt value (uOhm) */ >>> + if (of_property_read_u32(client->dev.of_node, "shunt-resistor", &rshunt) < 0) >>> + rshunt = INA233_RSHUNT_DEFAULT; >>> + >>> + /* read current_lsb value (uA) */ >>> + if (of_property_read_u16(client->dev.of_node, "ti,current-lsb", ¤t_lsb) < 0) >>> + current_lsb = INA233_CURRENT_LSB_DEFAULT; >>> + >> of_property_read_u16() returns -EOVERFLOW if the value provided was too large. >> This should be checked to avoid situations where the value provided in devicetree >> is too large. >> > Sorry I have a question, I can't get it to return -EOVERFLOW when I test it > I am using the following properties: > test16 = /bits/ 16 <0xfffd>; > of_property_read_u16 reads 0xfffd > > test16o = /bits/ 16 <0xfffdd>; > of_property_read_u16 reads 0xffdd > > test16o = <0xfffdd>; > of_property_read_u16 reads 0xf > > test16array = /bits/ 16 <0xfffd 0xfffe>; > of_property_read_u16 reads 0xfffd > > The same result for device_property_read_u16, it seems that a data > truncation occurs and none of them return -EOVERFLOW. > > So maybe there is no need to check EOVERFLOW? > Or maybe we could use the minimum and maximum of the binding to > indicate the range. > of_property_read_u16() calls of_property_read_u16_array(). The API documentation of of_property_read_u16_array() lists -ENODATA and -EOVERFLOW as possible error return values, in addition to -EINVAL. Ignoring those errors is not a good idea, even if it is not immediately obvious how to reproduce them. Guenter