From patchwork Thu Oct 31 14:48:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Gibson X-Patchwork-Id: 1187551 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-gpio-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="DhqUGCSd"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 473p9p0Ysyz9sP3 for ; Fri, 1 Nov 2019 01:49:02 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727990AbfJaOtB (ORCPT ); Thu, 31 Oct 2019 10:49:01 -0400 Received: from mail-pl1-f193.google.com ([209.85.214.193]:40933 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727841AbfJaOtB (ORCPT ); Thu, 31 Oct 2019 10:49:01 -0400 Received: by mail-pl1-f193.google.com with SMTP id e3so689709plt.7 for ; Thu, 31 Oct 2019 07:49:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=H8ar5IOsC7difEPwk7MYWfDqH58Z8xE8CDFxr3/ifJs=; b=DhqUGCSdZqpf3HkyGptB6HNCFMp38b5IdcuuLhEmf0vesrMYOo2Zn0rW6R9ZenXLf5 KF3RGJ7b0EcRwLWEhhnl7MIdZK7Ufbz72e8v2TWyWlii3dGzSWKoMukO+ZCbCWzljPrN p87jfmj9r6r8nDHhRD46SkITknm1+itZCVXXZI/XZwPVQC9n+F+CKibM1DBc55iTPKzu L+wqCUkS3HeDtGld5ng29QVxFc9avwml8w+WEdqa9oiS/DDrpLxngyx9nPlpItWM4K3x PWHTGjIXDf9YiJ6vFFHqyTz9R7mngDCa42PIWZ5+pd4WbpQMXOGXSNgfuKnMWthsY1L+ FyAQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=H8ar5IOsC7difEPwk7MYWfDqH58Z8xE8CDFxr3/ifJs=; b=eaIG6mEJaGD4NZo9qIuRvwsLmP5vw0ELApKG6DpKaicDLa0EJjxudLF6jTP5mCu/TQ NsKdAl2vkR0aF0Z2gcuZj15NrCOmhnzmvrIwK9W2dXl21BpTzPp/9VWHm1CFTkzfzJUa tl25OvBpHu4xOc2/Elhq7KaB9fCLhwyz80w1m636akXD7aNaapHRzCfs4o9+SphIxDCZ n09ru2HLA5yaXh7XqBK+0dnPSXzouN6105zJraOpbehmk76BWFp53VGlDzkhDoSCHHhI A0xXELW3M82bajG9dakgICZie3a5ZCeInq6ZFEfc7vjOR/bTgf32+bwZgdrKQ5qc7umF U1/A== X-Gm-Message-State: APjAAAVwxAU3/lFO8DwUyLPBeW9DjKK03jo07qr5LFrUtA/A8MyIF4Uh MHCffIf0iakNDE8j7/DCJjIafc2ZoICwBA== X-Google-Smtp-Source: APXvYqxHF7rNxD9WUwfwlEJP5sENL6clgC2BaR7iidugj0uA1ROv9uu2ZkFbj35s+8BWa8X6tCzB7Q== X-Received: by 2002:a17:902:bd06:: with SMTP id p6mr6460789pls.120.1572533340126; Thu, 31 Oct 2019 07:49:00 -0700 (PDT) Received: from sol.lan (220-235-109-115.dyn.iinet.net.au. [220.235.109.115]) by smtp.gmail.com with ESMTPSA id y126sm4568456pfg.74.2019.10.31.07.48.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 31 Oct 2019 07:48:59 -0700 (PDT) From: Kent Gibson To: linux-gpio@vger.kernel.org, bgolaszewski@baylibre.com, linus.walleij@linaro.org Cc: Kent Gibson Subject: [PATCH v2 1/2] gpiolib: move validation of line handle flags into helper function Date: Thu, 31 Oct 2019 22:48:24 +0800 Message-Id: <20191031144825.32105-2-warthog618@gmail.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191031144825.32105-1-warthog618@gmail.com> References: <20191031144825.32105-1-warthog618@gmail.com> MIME-Version: 1.0 Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Move validation of line handle flags into helper function. This reduces the size and complexity of linehandle_create and allows the validation to be reused elsewhere. Signed-off-by: Kent Gibson --- drivers/gpio/gpiolib.c | 93 +++++++++++++++++++++++------------------- 1 file changed, 51 insertions(+), 42 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index df27f05f9b8d..4e8fbd74a29c 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -427,6 +427,54 @@ struct linehandle_state { GPIOHANDLE_REQUEST_OPEN_DRAIN | \ GPIOHANDLE_REQUEST_OPEN_SOURCE) +static int linehandle_validate_flags(u32 flags) +{ + /* Return an error if an unknown flag is set */ + if (flags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) + return -EINVAL; + + /* + * Do not allow both INPUT & OUTPUT flags to be set as they are + * contradictory. + */ + if ((flags & GPIOHANDLE_REQUEST_INPUT) && + (flags & GPIOHANDLE_REQUEST_OUTPUT)) + return -EINVAL; + + /* + * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If + * the hardware actually supports enabling both at the same time the + * electrical result would be disastrous. + */ + if ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) && + (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) + return -EINVAL; + + /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */ + if (!(flags & GPIOHANDLE_REQUEST_OUTPUT) && + ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) || + (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE))) + return -EINVAL; + + /* Bias flags only allowed for input or output mode. */ + if (!((flags & GPIOHANDLE_REQUEST_INPUT) || + (flags & GPIOHANDLE_REQUEST_OUTPUT)) && + ((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) || + (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) || + (flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN))) + return -EINVAL; + + /* Only one bias flag can be set. */ + if (((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) && + (flags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN | + GPIOHANDLE_REQUEST_BIAS_PULL_UP))) || + ((flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) && + (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP))) + return -EINVAL; + + return 0; +} + static long linehandle_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) { @@ -528,48 +576,9 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) lflags = handlereq.flags; - /* Return an error if an unknown flag is set */ - if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) - return -EINVAL; - - /* - * Do not allow both INPUT & OUTPUT flags to be set as they are - * contradictory. - */ - if ((lflags & GPIOHANDLE_REQUEST_INPUT) && - (lflags & GPIOHANDLE_REQUEST_OUTPUT)) - return -EINVAL; - - /* - * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If - * the hardware actually supports enabling both at the same time the - * electrical result would be disastrous. - */ - if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) && - (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) - return -EINVAL; - - /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */ - if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) && - ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) || - (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))) - return -EINVAL; - - /* Bias flags only allowed for input or output mode. */ - if (!((lflags & GPIOHANDLE_REQUEST_INPUT) || - (lflags & GPIOHANDLE_REQUEST_OUTPUT)) && - ((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) || - (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) || - (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN))) - return -EINVAL; - - /* Only one bias flag can be set. */ - if (((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) && - (lflags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN | - GPIOHANDLE_REQUEST_BIAS_PULL_UP))) || - ((lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) && - (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP))) - return -EINVAL; + ret = linehandle_validate_flags(lflags); + if (ret) + return ret; lh = kzalloc(sizeof(*lh), GFP_KERNEL); if (!lh)