From nobody Fri Jan 2 05:00:13 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8060ACDB483 for ; Sun, 15 Oct 2023 11:26:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229731AbjJOL0k (ORCPT ); Sun, 15 Oct 2023 07:26:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229559AbjJOL0j (ORCPT ); Sun, 15 Oct 2023 07:26:39 -0400 Received: from mail-oa1-x42.google.com (mail-oa1-x42.google.com [IPv6:2001:4860:4864:20::42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C4AED9; Sun, 15 Oct 2023 04:26:36 -0700 (PDT) Received: by mail-oa1-x42.google.com with SMTP id 586e51a60fabf-1e59894d105so2127457fac.1; Sun, 15 Oct 2023 04:26:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1697369196; x=1697973996; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=aIP1YzudvKKCulfceAKZGd9fAuchfUzeWguBA1vwXP0=; b=H1V58LXNrf81PO5xqhvW3EYDfGnPdWkk0CFxmyUxqd7GxApCGrQihoVIqPoZWFTP9M /C2kVsFN+19IRre5ysnjfmXjmv7Bm3SV+bFIkuWWCNOT50mIOM12AVnVWMNNy2xk6TZl sP5v1VYBff+vyJmLM596bPvjFqIUJ3QfnYs0WTdyz/Ip//QODAzvVIACrARSLxy1p8Ro NG/g5vwpJljrAYFtVgFJJRLCMnqY3xSKCQ6HUDLbI+N6RfwlzFtpw02HW7+TTKg/OlVv HAPtBLpSng+obLFZIbovOP1FPgfoZJT/5+205gZBsN/azk6aVev9nN4A9Ltxbl5SYOPL QXGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697369196; x=1697973996; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=aIP1YzudvKKCulfceAKZGd9fAuchfUzeWguBA1vwXP0=; b=hs+cm+vXnXre8jhFWRfn1/Hxy8x139EEDoqim2QEVgrq5sfcSB4tdj4evLe8r7eNlj 82bxtM0CnKgVlfECbRZvh4tIpqzIqKNPRm9qLnr8dMXm0zPd8uW4sTO6FHck/NwAgl1v hyNUBpXf0HSyLzQyjudKuXEUwtpW77AQZwbXdrtPC6K2iVNbeLCMlVDy6V82dAAJzPhQ FxbDjcNb83K1Qqx9kiovLal+0HR8bjPftsh39vKIKtd38QlXCjSa+jSMQS73HBgSEn7X 7Vd7hrdnVpcwWdi/Q4dBRZMQPOgPdvttSodUPpGOncHo6EGocgjZttYsfxoZmifgk2oz ombA== X-Gm-Message-State: AOJu0YxIWWOgT6FNv5EG6dsH3YVdRxpB5iix6RpprqkW8qmKB+tVawIY pnHb4u7bhzywXfhlRJRTsUu3ZEKanQSyuge1U5o= X-Google-Smtp-Source: AGHT+IFgrv6NQ6q82bEbRsbaRFOHFqTc6aq6QkKCjP26uEWQC+Nh1guy2tlIIdxA51oYHMs1i3svMw== X-Received: by 2002:a05:6871:1d2:b0:1c3:91b9:e1e7 with SMTP id q18-20020a05687101d200b001c391b9e1e7mr35599924oad.21.1697369195625; Sun, 15 Oct 2023 04:26:35 -0700 (PDT) Received: from localhost ([2409:8a3c:3640:7481:178a:30e9:674c:c2f3]) by smtp.gmail.com with ESMTPSA id f9-20020a639c09000000b005781e026905sm6004455pge.56.2023.10.15.04.26.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 15 Oct 2023 04:26:35 -0700 (PDT) From: John Sanpe To: andrew.smirnov@gmail.com, cphealy@gmail.com, mm-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, John Sanpe Subject: [PATCH] lib/crc-ccitt: remove ccitt_false function Date: Sun, 15 Oct 2023 19:26:29 +0800 Message-ID: <20231015112629.872546-1-sanpeqf@gmail.com> X-Mailer: git-send-email 2.41.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The ccitt_false polynomial is consistent with itu-t, the only difference is that the initial crc value is different. Signed-off-by: John Sanpe --- .../driver-api/surface_aggregator/ssh.rst | 2 +- drivers/mfd/Kconfig | 2 +- drivers/mfd/rave-sp.c | 6 +- drivers/platform/surface/aggregator/Kconfig | 2 +- include/linux/crc-ccitt.h | 7 --- include/linux/surface_aggregator/serial_hub.h | 4 +- lib/crc-ccitt.c | 55 ------------------- 7 files changed, 8 insertions(+), 70 deletions(-) diff --git a/Documentation/driver-api/surface_aggregator/ssh.rst b/Document= ation/driver-api/surface_aggregator/ssh.rst index b955b673838b..58a757319931 100644 --- a/Documentation/driver-api/surface_aggregator/ssh.rst +++ b/Documentation/driver-api/surface_aggregator/ssh.rst @@ -39,7 +39,7 @@ Note that the standard disclaimer for this subsystem also= applies to this document: All of this has been reverse-engineered and may thus be erroneous and/or incomplete. =20 -All CRCs used in the following are two-byte ``crc_ccitt_false(0xffff, ...)= ``. +All CRCs used in the following are two-byte ``crc_itu_t(0xffff, ...)``. All multi-byte values are little-endian, there is no implicit padding betw= een values. =20 diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index 90ce58fd629e..925c19ee513b 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -2255,7 +2255,7 @@ config MFD_VEXPRESS_SYSREG config RAVE_SP_CORE tristate "RAVE SP MCU core driver" depends on SERIAL_DEV_BUS - select CRC_CCITT + select CRC_ITU_T help Select this to get support for the Supervisory Processor device found on several devices in RAVE line of hardware. diff --git a/drivers/mfd/rave-sp.c b/drivers/mfd/rave-sp.c index da50eba10014..44ce7e730744 100644 --- a/drivers/mfd/rave-sp.c +++ b/drivers/mfd/rave-sp.c @@ -9,7 +9,7 @@ */ =20 #include -#include +#include #include #include #include @@ -251,11 +251,11 @@ static void csum_8b2c(const u8 *buf, size_t size, u8 = *crc) =20 static void csum_ccitt(const u8 *buf, size_t size, u8 *crc) { - const u16 calculated =3D crc_ccitt_false(0xffff, buf, size); + const u16 calculated =3D crc_itu_t(0xffff, buf, size); =20 /* * While the rest of the wire protocol is little-endian, - * CCITT-16 CRC in RDU2 device is sent out in big-endian order. + * ITU-T-16 CRC in RDU2 device is sent out in big-endian order. */ put_unaligned_be16(calculated, crc); } diff --git a/drivers/platform/surface/aggregator/Kconfig b/drivers/platform= /surface/aggregator/Kconfig index 88afc38ffdc5..957c216c180c 100644 --- a/drivers/platform/surface/aggregator/Kconfig +++ b/drivers/platform/surface/aggregator/Kconfig @@ -5,7 +5,7 @@ menuconfig SURFACE_AGGREGATOR tristate "Microsoft Surface System Aggregator Module Subsystem and Driver= s" depends on SERIAL_DEV_BUS depends on ACPI && !RISCV - select CRC_CCITT + select CRC_ITU_T help The Surface System Aggregator Module (Surface SAM or SSAM) is an embedded controller (EC) found on 5th- and later-generation Microsoft diff --git a/include/linux/crc-ccitt.h b/include/linux/crc-ccitt.h index 72c92c396bb8..cd4f420231ba 100644 --- a/include/linux/crc-ccitt.h +++ b/include/linux/crc-ccitt.h @@ -5,19 +5,12 @@ #include =20 extern u16 const crc_ccitt_table[256]; -extern u16 const crc_ccitt_false_table[256]; =20 extern u16 crc_ccitt(u16 crc, const u8 *buffer, size_t len); -extern u16 crc_ccitt_false(u16 crc, const u8 *buffer, size_t len); =20 static inline u16 crc_ccitt_byte(u16 crc, const u8 c) { return (crc >> 8) ^ crc_ccitt_table[(crc ^ c) & 0xff]; } =20 -static inline u16 crc_ccitt_false_byte(u16 crc, const u8 c) -{ - return (crc << 8) ^ crc_ccitt_false_table[(crc >> 8) ^ c]; -} - #endif /* _LINUX_CRC_CCITT_H */ diff --git a/include/linux/surface_aggregator/serial_hub.h b/include/linux/= surface_aggregator/serial_hub.h index 5c4ae1a26183..d8dbef6b7fc2 100644 --- a/include/linux/surface_aggregator/serial_hub.h +++ b/include/linux/surface_aggregator/serial_hub.h @@ -12,7 +12,7 @@ #ifndef _LINUX_SURFACE_AGGREGATOR_SERIAL_HUB_H #define _LINUX_SURFACE_AGGREGATOR_SERIAL_HUB_H =20 -#include +#include #include #include #include @@ -188,7 +188,7 @@ static_assert(sizeof(struct ssh_command) =3D=3D 8); */ static inline u16 ssh_crc(const u8 *buf, size_t len) { - return crc_ccitt_false(0xffff, buf, len); + return crc_itu_t(0xffff, buf, len); } =20 /* diff --git a/lib/crc-ccitt.c b/lib/crc-ccitt.c index d1a7d29d2ac9..9cddf35d3b66 100644 --- a/lib/crc-ccitt.c +++ b/lib/crc-ccitt.c @@ -49,46 +49,6 @@ u16 const crc_ccitt_table[256] =3D { }; EXPORT_SYMBOL(crc_ccitt_table); =20 -/* - * Similar table to calculate CRC16 variant known as CRC-CCITT-FALSE - * Reflected bits order, does not augment final value. - */ -u16 const crc_ccitt_false_table[256] =3D { - 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5, 0x60C6, 0x70E7, - 0x8108, 0x9129, 0xA14A, 0xB16B, 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF, - 0x1231, 0x0210, 0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6, - 0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C, 0xF3FF, 0xE3DE, - 0x2462, 0x3443, 0x0420, 0x1401, 0x64E6, 0x74C7, 0x44A4, 0x5485, - 0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D, - 0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6, 0x5695, 0x46B4, - 0xB75B, 0xA77A, 0x9719, 0x8738, 0xF7DF, 0xE7FE, 0xD79D, 0xC7BC, - 0x48C4, 0x58E5, 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823, - 0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969, 0xA90A, 0xB92B, - 0x5AF5, 0x4AD4, 0x7AB7, 0x6A96, 0x1A71, 0x0A50, 0x3A33, 0x2A12, - 0xDBFD, 0xCBDC, 0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A, - 0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03, 0x0C60, 0x1C41, - 0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD, 0xAD2A, 0xBD0B, 0x8D68, 0x9D49, - 0x7E97, 0x6EB6, 0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70, - 0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A, 0x9F59, 0x8F78, - 0x9188, 0x81A9, 0xB1CA, 0xA1EB, 0xD10C, 0xC12D, 0xF14E, 0xE16F, - 0x1080, 0x00A1, 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067, - 0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C, 0xE37F, 0xF35E, - 0x02B1, 0x1290, 0x22F3, 0x32D2, 0x4235, 0x5214, 0x6277, 0x7256, - 0xB5EA, 0xA5CB, 0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D, - 0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405, - 0xA7DB, 0xB7FA, 0x8799, 0x97B8, 0xE75F, 0xF77E, 0xC71D, 0xD73C, - 0x26D3, 0x36F2, 0x0691, 0x16B0, 0x6657, 0x7676, 0x4615, 0x5634, - 0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9, 0xB98A, 0xA9AB, - 0x5844, 0x4865, 0x7806, 0x6827, 0x18C0, 0x08E1, 0x3882, 0x28A3, - 0xCB7D, 0xDB5C, 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A, - 0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0, 0x2AB3, 0x3A92, - 0xFD2E, 0xED0F, 0xDD6C, 0xCD4D, 0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9, - 0x7C26, 0x6C07, 0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1, - 0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA, 0x8FD9, 0x9FF8, - 0x6E17, 0x7E36, 0x4E55, 0x5E74, 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0 -}; -EXPORT_SYMBOL(crc_ccitt_false_table); - /** * crc_ccitt - recompute the CRC (CRC-CCITT variant) for the data * buffer @@ -104,20 +64,5 @@ u16 crc_ccitt(u16 crc, u8 const *buffer, size_t len) } EXPORT_SYMBOL(crc_ccitt); =20 -/** - * crc_ccitt_false - recompute the CRC (CRC-CCITT-FALSE variant) - * for the data buffer - * @crc: previous CRC value - * @buffer: data pointer - * @len: number of bytes in the buffer - */ -u16 crc_ccitt_false(u16 crc, u8 const *buffer, size_t len) -{ - while (len--) - crc =3D crc_ccitt_false_byte(crc, *buffer++); - return crc; -} -EXPORT_SYMBOL(crc_ccitt_false); - MODULE_DESCRIPTION("CRC-CCITT calculations"); MODULE_LICENSE("GPL"); --=20 2.41.0