From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 934EF2F547F; Fri, 23 Jan 2026 15:53:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769183638; cv=none; b=pM97bkwkVuf2ds8sQucBQlyvwLnhO4xnqWS6FDntcjbXfH38PuyeFCzvVwa1+nCPoxd5CYph+us3vylKs2HcA3HJiKRNHLnZtvimz0/v6pPyEd3dMeuIupBEWdM8nm2UFkO4JgxPIFoFQIA6bIJa0yirF6Yu11v5C8jjkqOdZxM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769183638; c=relaxed/simple; bh=R7vm4aZOBiDNx/wHB/tpHckhIayyxKVEOFE8hcpvIDc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=rCDQ9QKEmToeRud8DjbxDx5pRXBb8/7Nn/0+afU5jf+d6Ngyy11uKOVPH6ZlTbW85xtX4Eb8c9t/apqikMQPu3GQgIBFqTE9AjGXKNL5cuhEAWnMzbVXncZfL5jGbkWDzotzjZFQOdWEFsr9wKTnraURirO7UT5T6RVEf1u5OsM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CQUcC6/u; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CQUcC6/u" Received: by smtp.kernel.org (Postfix) with ESMTPS id 55D86C2BC86; Fri, 23 Jan 2026 15:53:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769183638; bh=R7vm4aZOBiDNx/wHB/tpHckhIayyxKVEOFE8hcpvIDc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=CQUcC6/unzL2ZueF+21+wDupWUh2pAT8yhhQlShP4uIyN9i+XRyXRKpb0yOCn6dB4 H96qO1b26jgkvT+gRFtdxA4QVMcWC29Iv1j9UbYqZeKMSdpOv2cAsJAjWJWVMMB5lb DHtNdIedMSM7pJ7r4+wI7nyoqmkOHcNVNRduOYbiuo+26Sded49ITEtcEv701JLnJq 1sOPiq+j1yB6fBV3p2tbQWaWx2EceT8u+VMVFhSKqDnowj9e4py7kaF8X27ERWo2xc ZCqTcUJaFS8FKIcuewjJVTyDpVI9htPl7LllwTugVzhoCTw75PwTzrerjVSqVUbyVJ AezjWI6x2FBPQ== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48C1FD74EF3; Fri, 23 Jan 2026 15:53:58 +0000 (UTC) From: Rodrigo Alencar via B4 Relay Date: Fri, 23 Jan 2026 15:53:07 +0000 Subject: [PATCH v5 2/8] iio: core: add fixed point parsing with 64-bit parts 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-Transfer-Encoding: 7bit Message-Id: <20260123-adf41513-iio-driver-v5-2-2dce812a2dda@analog.com> References: <20260123-adf41513-iio-driver-v5-0-2dce812a2dda@analog.com> In-Reply-To: <20260123-adf41513-iio-driver-v5-0-2dce812a2dda@analog.com> To: linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-doc@vger.kernel.org Cc: Jonathan Cameron , David Lechner , Andy Shevchenko , Lars-Peter Clausen , Michael Hennerich , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jonathan Corbet , Rodrigo Alencar X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1769183636; l=5726; i=rodrigo.alencar@analog.com; s=default; h=from:subject:message-id; bh=FiReBaiuJATL+Y1igulBqy6KALX1/IMCZ9XVcyWaYR4=; b=gIsHt1MgZgLQtJF1hn7ZhKruszvDsacZs621EBCtIrv3Ect1ON0pACf1cua87qzu2+iEgY/vc K16QguQNTjtBb7TnP8wNg3N2OP4FyJ5dYSbr1kLheXfQ7Wvrih9LwJ0 X-Developer-Key: i=rodrigo.alencar@analog.com; a=ed25519; pk=ULeHbgU/OYh/PG/4anHDfLgldFItQHAhOktYRVLMFRo= X-Endpoint-Received: by B4 Relay for rodrigo.alencar@analog.com/default with auth_id=561 X-Original-From: Rodrigo Alencar Reply-To: rodrigo.alencar@analog.com From: Rodrigo Alencar Add iio_str_to_fixpoint64() function that leverages simple_strtoull() to parse numbers from a string. A helper function __iio_str_to_fixpoint64() replaces __iio_str_to_fixpoint() implementation, extending its usage for 64-bit fixed-point parsing. Signed-off-by: Rodrigo Alencar --- drivers/iio/industrialio-core.c | 151 +++++++++++++++++++++++++++------------- include/linux/iio/iio.h | 2 + 2 files changed, 103 insertions(+), 50 deletions(-) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index f69deefcfb6f..4ad4f1b29421 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -881,6 +881,77 @@ static ssize_t iio_read_channel_info_avail(struct device *dev, } } +/** + * __iio_str_to_fixpoint64() - Parse a fixed-point number from a string + * @str: The string to parse + * @fract_mult: Multiplier for the first decimal place, should be a power of 10 + * @integer: The integer part of the number + * @fract: The fractional part of the number + * @scale_db: True if this should parse as dB + * + * This variant uses 64-bit integers for both integer and fractional parts. + * + * Returns: + * 0 on success, or a negative error code if the string could not be parsed. + */ +static int __iio_str_to_fixpoint64(const char *str, u64 fract_mult, + s64 *integer, s64 *fract, bool scale_db) +{ + u64 i = 0, f = 0; + char *end; + int digit_count, precision = ffs(fract_mult); + bool negative = false; + + if (str[0] == '-') { + negative = true; + str++; + } else if (str[0] == '+') { + str++; + } + + i = simple_strtoull(str, &end, 10); + digit_count = end - str; + if (digit_count > 20) + return -EINVAL; + + if (precision && *end == '.') { + str = end + 1; + f = simple_strtoull(str, &end, 10); + digit_count = end - str; + if (!digit_count || digit_count > 20) + return -EINVAL; + + if (digit_count > precision) { + digit_count -= precision; + f = div64_u64(f, int_pow(10, digit_count)); + } else { + digit_count = precision - digit_count; + f *= int_pow(10, digit_count); + } + } else if (!digit_count) { + return -EINVAL; + } + + if (scale_db) { + /* Ignore the dB suffix */ + if (!strncmp(end, " dB", sizeof(" dB") - 1)) + end += sizeof(" dB") - 1; + else if (!strncmp(end, "dB", sizeof("dB") - 1)) + end += sizeof("dB") - 1; + } + + if (*end == '\n') + end++; + + if (*end != '\0') + return -EINVAL; + + *integer = (negative && i) ? -i : i; + *fract = (negative && !i) ? -f : f; + + return 0; +} + /** * __iio_str_to_fixpoint() - Parse a fixed-point number from a string * @str: The string to parse @@ -895,63 +966,43 @@ static ssize_t iio_read_channel_info_avail(struct device *dev, static int __iio_str_to_fixpoint(const char *str, int fract_mult, int *integer, int *fract, bool scale_db) { - int i = 0, f = 0; - bool integer_part = true, negative = false; + s64 integer64, fract64; + int ret; - if (fract_mult == 0) { - *fract = 0; + ret = __iio_str_to_fixpoint64(str, fract_mult, &integer64, &fract64, + scale_db); + if (ret) + return ret; - return kstrtoint(str, 0, integer); - } + if (integer64 < INT_MIN || integer64 > INT_MAX || + fract64 < INT_MIN || fract64 > INT_MAX) + return -ERANGE; - if (str[0] == '-') { - negative = true; - str++; - } else if (str[0] == '+') { - str++; - } - - while (*str) { - if ('0' <= *str && *str <= '9') { - if (integer_part) { - i = i * 10 + *str - '0'; - } else { - f += fract_mult * (*str - '0'); - fract_mult /= 10; - } - } else if (*str == '\n') { - if (*(str + 1) == '\0') - break; - return -EINVAL; - } else if (!strncmp(str, " dB", sizeof(" dB") - 1) && scale_db) { - /* Ignore the dB suffix */ - str += sizeof(" dB") - 1; - continue; - } else if (!strncmp(str, "dB", sizeof("dB") - 1) && scale_db) { - /* Ignore the dB suffix */ - str += sizeof("dB") - 1; - continue; - } else if (*str == '.' && integer_part) { - integer_part = false; - } else { - return -EINVAL; - } - str++; - } - - if (negative) { - if (i) - i = -i; - else - f = -f; - } - - *integer = i; - *fract = f; + *integer = integer64; + *fract = fract64; return 0; } +/** + * iio_str_to_fixpoint64() - Parse a fixed-point number from a string + * @str: The string to parse + * @fract_mult: Multiplier for the first decimal place, should be a power of 10 + * @integer: The integer part of the number + * @fract: The fractional part of the number + * + * This variant uses 64-bit integers for both integer and fractional parts. + * + * Returns: + * 0 on success, or a negative error code if the string could not be parsed. + */ +int iio_str_to_fixpoint64(const char *str, u64 fract_mult, s64 *integer, + s64 *fract) +{ + return __iio_str_to_fixpoint64(str, fract_mult, integer, fract, false); +} +EXPORT_SYMBOL_GPL(iio_str_to_fixpoint64); + /** * iio_str_to_fixpoint() - Parse a fixed-point number from a string * @str: The string to parse diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index 872ebdf0dd77..432cd26fc9d0 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -940,6 +940,8 @@ int iio_active_scan_mask_index(struct iio_dev *indio_dev); ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals); +int iio_str_to_fixpoint64(const char *str, u64 fract_mult, s64 *integer, + s64 *fract); int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer, int *fract); -- 2.43.0