From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yb1-f201.google.com (mail-yb1-f201.google.com [209.85.219.201]) (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 2BF875809 for ; Fri, 1 Jul 2022 23:21:51 +0000 (UTC) Received: by mail-yb1-f201.google.com with SMTP id h198-20020a25d0cf000000b0066e14d5ad1dso631401ybg.8 for ; Fri, 01 Jul 2022 16:21:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:message-id:mime-version:subject:from:to:cc; bh=r1hNWMzTHbP1T3u0oJfFG4ATF129b7TBwtFs10zIbH0=; b=AfniH5QTWUN+wqcSlLlKuJx5yJp8JJHk89CfEEMl5lQ1ICN/xG92kx5WNxs+hwMLDj y1MPwtf1lGA1NblcuJoqXrs4bHlUiq1iRR4w2azrECLCuIIInWJydMnwbeDO9A1gacJ3 6MGIh5dly4GfP0UxK6LkaOJEKAyc0fb9wkYVNqLZI/LJvBlKOBg9aYrMP5pGDiKej7u1 +TSLG69EXbh9UkRVy1yh07pPtZuKzomVtNA3mYLLapw8CWSLayla3G2XPDgskRdknVyf NEpGzNbVutswz0xnFL6MooUMFGxU0t5boARFQ0DJRPTPIgfUU9whtp2A/smT/aBmeW2C fGJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=r1hNWMzTHbP1T3u0oJfFG4ATF129b7TBwtFs10zIbH0=; b=mAZUwAgLgu+raMyIHhM6+Ltbv9pEfxpUVWFc2un6JA2Py6CwXbvtSUregG5EWA/804 T+xIoA56okG+KJ6Ha7XqqKEKI8EnMDbWQ/WluyX1VLeL2Ld3otsJfSHsKot9erpGnmD+ xdqmkKDdzrBabC2/T9q2QFj9Mm5g3Mj7QNkrNncX/Qv4lC+axtfdd3bQko5W8P9Nbcme vlBFIJokspnFAMIgBU/kmgc2eegsjEdrBZuou+u+vr1jdT/K6u6dswirYalec3pMkuMi lJv12bedGnwNjcyaeUdp8Ef6+kgXKU5rCHFBma5SygUdX7wydzNf8SB6GWbtgYoV3VbT vkvQ== X-Gm-Message-State: AJIora9K62bk7WjSwuPZFVO22+A1uqPi67PqVE1dfPeounWFbJtpyXVp 60glX2Ma3UNTgqS7RTGnEQMJogQk2pNJPmOFgg== X-Google-Smtp-Source: AGRyM1vS8lR6ohgVW9YKUmSTvCAVBF+D2wOLXwW/aqjioj8VQIMa9zehx7RkG7my6+BiriAauGh24+9hI4ngKzSURg== X-Received: from justinstitt.mtv.corp.google.com ([2620:15c:211:202:a7a5:71:ddd5:892b]) (user=justinstitt job=sendgmr) by 2002:a0d:f9c1:0:b0:31b:726f:9ef2 with SMTP id j184-20020a0df9c1000000b0031b726f9ef2mr20290827ywf.252.1656717710164; Fri, 01 Jul 2022 16:21:50 -0700 (PDT) Date: Fri, 1 Jul 2022 16:20:31 -0700 Message-Id: <20220701232031.2639134-1-justinstitt@google.com> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.37.0.rc0.161.g10f37bed90-goog Subject: [PATCH] eeprom: idt_89hpesx: fix clang -Wformat warnings From: Justin Stitt To: Greg Kroah-Hartman Cc: Nathan Chancellor , Nick Desaulniers , Tom Rix , linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Justin Stitt Content-Type: text/plain; charset="UTF-8" see warnings: | drivers/misc/eeprom/idt_89hpesx.c:570:5: error: format specifies type | 'unsigned char' but the argument has type 'u16' (aka 'unsigned short') | [-Werror,-Wformat] memaddr); - | drivers/misc/eeprom/idt_89hpesx.c:579:5: error: format specifies type | 'unsigned char' but the argument has type 'u16' (aka 'unsigned short') | [-Werror,-Wformat] memaddr); - | drivers/misc/eeprom/idt_89hpesx.c:814:4: error: format specifies type | 'unsigned short' but the argument has type 'unsigned int' | [-Werror,-Wformat] CSR_REAL_ADDR(csraddr)); There's an ongoing movement to eventually enable the -Wformat flag for clang. See: https://github.com/ClangBuiltLinux/linux/issues/378 The format specifier for idt_89hpesx.c:570 and 579 was `0x%02hhx`. The part we care about `%hhx` describes a single byte format, wherein the leftmost byte of our u16 type (of which memaddr is) is truncated. example: ``` uint16_t x = 0xbabe; printf("%hhx\n", x); // output is: be // we lost 'ba' ``` There exists a similar issue at idt_89hpesx.c:814 which involves the CSR_REAL_ADDR macro. This macro returns a u16 but due to default argument promotion for variadic functions (printf-like) actually provides an int to the dev_err method. My proposed solution is to expand the width of the format specifier to fully encompass the provided argument (which is promoted to an int, see below). I opted for '%x' as this specifies an unsigned hexadecimal integer which, with a guarantee, can represent all the values of a u16. As per C11 6.3.1.1: (https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1548.pdf) `If an int can represent all values of the original type ..., the value is converted to an int; otherwise, it is converted to an unsigned int. These are called the integer promotions.` Link: https://github.com/ClangBuiltLinux/linux/issues/378 Signed-off-by: Justin Stitt --- drivers/misc/eeprom/idt_89hpesx.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/misc/eeprom/idt_89hpesx.c b/drivers/misc/eeprom/idt_89hpesx.c index b0cff4b152da..42eac114edd7 100644 --- a/drivers/misc/eeprom/idt_89hpesx.c +++ b/drivers/misc/eeprom/idt_89hpesx.c @@ -566,7 +566,7 @@ static int idt_eeprom_read_byte(struct idt_89hpesx_dev *pdev, u16 memaddr, eeseq.memaddr = cpu_to_le16(memaddr); ret = pdev->smb_write(pdev, &smbseq); if (ret != 0) { - dev_err(dev, "Failed to init eeprom addr 0x%02hhx", + dev_err(dev, "Failed to init eeprom addr 0x%02x", memaddr); break; } @@ -575,7 +575,7 @@ static int idt_eeprom_read_byte(struct idt_89hpesx_dev *pdev, u16 memaddr, smbseq.bytecnt = EEPROM_RD_CNT; ret = pdev->smb_read(pdev, &smbseq); if (ret != 0) { - dev_err(dev, "Failed to read eeprom data 0x%02hhx", + dev_err(dev, "Failed to read eeprom data 0x%02x", memaddr); break; } @@ -810,7 +810,7 @@ static int idt_csr_read(struct idt_89hpesx_dev *pdev, u16 csraddr, u32 *data) smbseq.bytecnt = CSR_RD_CNT; ret = pdev->smb_read(pdev, &smbseq); if (ret != 0) { - dev_err(dev, "Failed to read csr 0x%04hx", + dev_err(dev, "Failed to read csr 0x%04x", CSR_REAL_ADDR(csraddr)); goto err_mutex_unlock; } -- 2.37.0.rc0.161.g10f37bed90-goog