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) From patchwork Thu Oct 31 14:48:25 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Gibson X-Patchwork-Id: 1187552 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="VrL0tim7"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 473p9s0z4Sz9sP3 for ; Fri, 1 Nov 2019 01:49:05 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727995AbfJaOtE (ORCPT ); Thu, 31 Oct 2019 10:49:04 -0400 Received: from mail-pl1-f195.google.com ([209.85.214.195]:40938 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727841AbfJaOtE (ORCPT ); Thu, 31 Oct 2019 10:49:04 -0400 Received: by mail-pl1-f195.google.com with SMTP id e3so689777plt.7 for ; Thu, 31 Oct 2019 07:49:03 -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=/KIWhZ+w5Vi6sDcWBegYkb0Odafz7JIkaIVtVTdkUHE=; b=VrL0tim7IuKEvKl8nNhQj2Zq24OaMBiotM3mhPE7+QITy0l0BIWz+1JVbucDKwRqjN SDrfcRYB3sh/IU4B9he+Snia+6O+eqbcCbIpatKNKT4RQ9ov1NG8/Wq47Onu5HTl8nbY VuxU6Pih+3mUBzVGxhm6G6xkmnnqAIEZZGfADi0vBcgyftjLXL2Q88p4PKx4hJAESnIQ +XfiIuow/D9X338Pr4AojOtz8YyrF3ethbZ5AQKdUWaPIaS0LChiEpDLOuVc9duV4ohq q79EsUrdDhah36I4EDvg0NGYlUwpBo51GuBTVFEA1/qi1oW5ghQGLM7/MxnPSPannJIe Eaqg== 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=/KIWhZ+w5Vi6sDcWBegYkb0Odafz7JIkaIVtVTdkUHE=; b=ahS2EM3fiL3EN7LU87BEQSBfSNd454cO22jc679se0OBfqDCeiRwbai0sHxPnfznjz CY2l2yZJMkGnRcjoHG+zJP+WhPscacg5XO0IK0GiYbfglT3d7QHjhpzPNYgIATgUE8P3 0mZr+VIpVCjYP34gY9bc6VsLf0+yxLPPTTJrDuzvKO9zfyaF9IArwJTXLIkTHUvFaQgH ju8JLcnJKQecerpy/atVm+kzvtS2fM+U8JHxjJdJwhDeUYoIVx2PEfmU2NYiwP4v4D54 sYKun/1486XKSaffv3mmqnm8AHKnPT31wtewEoyWm2QJB+/QrA0gqn+5sEmn1dHQPSzM wNNg== X-Gm-Message-State: APjAAAWI5oAI3ohhzhUlIjb+BO6lS9UUB5TIbVcYxuKr0a581oDj5Umm D87YkZs70o9JFyeP0qm8UGiaNwncNuyUjg== X-Google-Smtp-Source: APXvYqznKml7dZKxqWa18qc60rHC7NAT/JVnR/qEL42uAMyu8GzZMBcSKF9oR8pknMgGIH4Jz2n4ng== X-Received: by 2002:a17:902:7b98:: with SMTP id w24mr6502022pll.299.1572533343129; Thu, 31 Oct 2019 07:49:03 -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.74.2019.10.31.07.49.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 31 Oct 2019 07:49:02 -0700 (PDT) From: Kent Gibson To: linux-gpio@vger.kernel.org, bgolaszewski@baylibre.com, linus.walleij@linaro.org Cc: Kent Gibson Subject: [PATCH v2 2/2] gpio: add new SET_CONFIG ioctl() to gpio chardev Date: Thu, 31 Oct 2019 22:48:25 +0800 Message-Id: <20191031144825.32105-3-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 Add the GPIOHANDLE_SET_CONFIG_IOCTL to the gpio chardev. The ioctl allows some of the configuration of a requested handle to be changed without having to release the line. The primary use case is the changing of direction for bi-directional lines. Based on initial work by Bartosz Golaszewski Signed-off-by: Kent Gibson --- drivers/gpio/gpiolib.c | 68 +++++++++++++++++++++++++++++++++++++++ include/uapi/linux/gpio.h | 18 +++++++++++ 2 files changed, 86 insertions(+) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 4e8fbd74a29c..7c026ee58917 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -475,6 +475,73 @@ static int linehandle_validate_flags(u32 flags) return 0; } +static void linehandle_configure_flag(unsigned long *flagsp, + u32 bit, bool active) +{ + if (active) + set_bit(bit, flagsp); + else + clear_bit(bit, flagsp); +} + +static long linehandle_set_config(struct linehandle_state *lh, + void __user *ip) +{ + struct gpiohandle_config gcnf; + struct gpio_desc *desc; + int i, ret; + u32 lflags; + unsigned long *flagsp; + + if (copy_from_user(&gcnf, ip, sizeof(gcnf))) + return -EFAULT; + + lflags = gcnf.flags; + ret = linehandle_validate_flags(lflags); + if (ret) + return ret; + + for (i = 0; i < lh->numdescs; i++) { + desc = lh->descs[i]; + flagsp = &desc->flags; + + linehandle_configure_flag(flagsp, FLAG_ACTIVE_LOW, + lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW); + + linehandle_configure_flag(flagsp, FLAG_OPEN_DRAIN, + lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN); + + linehandle_configure_flag(flagsp, FLAG_OPEN_SOURCE, + lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE); + + linehandle_configure_flag(flagsp, FLAG_PULL_UP, + lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP); + + linehandle_configure_flag(flagsp, FLAG_PULL_DOWN, + lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN); + + linehandle_configure_flag(flagsp, FLAG_BIAS_DISABLE, + lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE); + + /* + * Lines have to be requested explicitly for input + * or output, else the line will be treated "as is". + */ + if (lflags & GPIOHANDLE_REQUEST_OUTPUT) { + int val = !!gcnf.default_values[i]; + + ret = gpiod_direction_output(desc, val); + if (ret) + return ret; + } else if (lflags & GPIOHANDLE_REQUEST_INPUT) { + ret = gpiod_direction_input(desc); + if (ret) + return ret; + } + } + return 0; +} + static long linehandle_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) { @@ -525,6 +592,8 @@ static long linehandle_ioctl(struct file *filep, unsigned int cmd, lh->descs, NULL, vals); + } else if (cmd == GPIOHANDLE_SET_CONFIG_IOCTL) { + return linehandle_set_config(lh, ip); } return -EINVAL; } diff --git a/include/uapi/linux/gpio.h b/include/uapi/linux/gpio.h index 7cc21c3b0839..799cf823d493 100644 --- a/include/uapi/linux/gpio.h +++ b/include/uapi/linux/gpio.h @@ -100,6 +100,24 @@ struct gpiohandle_request { int fd; }; +/** + * struct gpiohandle_config - Configuration for a GPIO handle request + * @flags: updated flags for the requested GPIO lines, such as + * GPIOHANDLE_REQUEST_OUTPUT, GPIOHANDLE_REQUEST_ACTIVE_LOW etc, OR:ed + * together + * @default_values: if the GPIOHANDLE_REQUEST_OUTPUT is set in flags, + * this specifies the default output value, should be 0 (low) or + * 1 (high), anything else than 0 or 1 will be interpreted as 1 (high) + * @padding: reserved for future use and should be zero filled + */ +struct gpiohandle_config { + __u32 flags; + __u8 default_values[GPIOHANDLES_MAX]; + __u32 padding[4]; /* padding for future use */ +}; + +#define GPIOHANDLE_SET_CONFIG_IOCTL _IOWR(0xB4, 0x0a, struct gpiohandle_config) + /** * struct gpiohandle_data - Information of values on a GPIO handle * @values: when getting the state of lines this contains the current