From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19C2FC433EA for ; Sat, 25 Jul 2020 04:21:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC06020792 for ; Sat, 25 Jul 2020 04:21:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Hc2sXhkB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726946AbgGYEVx (ORCPT ); Sat, 25 Jul 2020 00:21:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35690 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725766AbgGYEVx (ORCPT ); Sat, 25 Jul 2020 00:21:53 -0400 Received: from mail-pj1-x1041.google.com (mail-pj1-x1041.google.com [IPv6:2607:f8b0:4864:20::1041]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 40146C0619D3; Fri, 24 Jul 2020 21:21:53 -0700 (PDT) Received: by mail-pj1-x1041.google.com with SMTP id a9so6428252pjd.3; Fri, 24 Jul 2020 21:21:53 -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=fapEZEJ9DNw3FFZOxwjkh9bO3pSC0CYjBXyWNSjW8/M=; b=Hc2sXhkBeA5aT/22dTUKuNW8txca6l6WFuEr33aooY8tBXUnwvo/jor254iLcgd/AZ T9DDScdUNdwYAW3n5IOyWO0qld1mbJbqK4bQrYV3fzfjgKkoE+SseuoN12aIdYB+aw8H oqqsME5u86umqVk5AcMGuO2xWwOJIM9NECCkXM7HPM8GPwohn7HArvtKCFaVQjWgTQfV MGnu7ZaP3qB8I4uJbarupxxjNA94VqPABmqCF+jTKBoXjKRgQWY6Uwmt3Dr5ASt6zzVa FGILibfMMFIlwss5BOwu9Jq5NQek1XwqkhsZxSVK+ulQkP+X0kHsDdY7TVaBME/hIWJL bW/A== 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=fapEZEJ9DNw3FFZOxwjkh9bO3pSC0CYjBXyWNSjW8/M=; b=hbEY0ZwdQWb5abnqRJOZ0oQyWv5FevGn+FqLMO2bj0THLEpkc+XWk1wO/T1G+GZ0/z f/RYCjc/5B/fMkyIrF7DArpG+jk3GNJZ3j7dJBUHoe437mEUyWayqe/ttrOSG7hIMA8h bpGrq1CwIFD8xdiq+PXDujeNkMJbmmLsvL0DzNPp3YyitTqX88i2kMM/7WO2mL4ZlXr7 Py4Mm8G9vsKMf5VDZBnOrRAJQzBigjUXUETcw65ChnippnglZ6VbzBKhS5PHJgho37Rt wMc543b0yb8K9BuqUfbU+fUVhweGrvKy7tnaWCowTCH52RxadbO63qXqXL9nAeq0d1Zz VdWw== X-Gm-Message-State: AOAM531BtEeZHunyvriXJkaBpvBExidSr/s60L1o9+6o8h8k6z7eR0Sz GhqRkHdx1CblWjxkMRC4wWnTioNt X-Google-Smtp-Source: ABdhPJzfPMVxbLtrelmVqBheSfa77gvCUdYanx64Nx1v+VddqDlbHuO0cV9XEfixMA+Cqy5e5rjKyg== X-Received: by 2002:a17:902:bb82:: with SMTP id m2mr10907985pls.61.1595650912321; Fri, 24 Jul 2020 21:21:52 -0700 (PDT) Received: from sol.lan (106-69-185-93.dyn.iinet.net.au. [106.69.185.93]) by smtp.gmail.com with ESMTPSA id p1sm885320pjp.10.2020.07.24.21.21.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Jul 2020 21:21:51 -0700 (PDT) From: Kent Gibson To: linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org, bgolaszewski@baylibre.com, linus.walleij@linaro.org Cc: Kent Gibson Subject: [PATCH v2 08/18] gpiolib: cdev: support GPIOLINE_SET_CONFIG_IOCTL Date: Sat, 25 Jul 2020 12:19:45 +0800 Message-Id: <20200725041955.9985-9-warthog618@gmail.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200725041955.9985-1-warthog618@gmail.com> References: <20200725041955.9985-1-warthog618@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Add support for GPIOLINE_SET_CONFIG_IOCTL, the uAPI v2 line set config ioctl. Signed-off-by: Kent Gibson --- drivers/gpio/gpiolib-cdev.c | 91 +++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index 8caebb460557..9d944ca0ff59 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -417,6 +418,8 @@ struct edge_detector { * @seqno: the sequence number for edge events generated on all lines in * this line request. Note that this is not used when @num_descs is 1, as * the line_seqno is then the same and is cheaper to calculate. + * @config_mutex: mutex for serializing ioctl() calls to ensure consistency + * of configuration, partiuclarly multi-step accesses to desc flags. * @edets: an array of edge detectors, of size @num_descs * @descs: the GPIO descriptors held by this line request, with @num_descs * elements. @@ -428,6 +431,7 @@ struct line { wait_queue_head_t wait; DECLARE_KFIFO_PTR(events, struct gpioline_event); atomic_t seqno; + struct mutex config_mutex; struct edge_detector *edets; /* descs must be last so it can be dynamically sized */ struct gpio_desc *descs[]; @@ -709,6 +713,30 @@ static int gpioline_config_validate(struct gpioline_config *lc, int num_lines) return 0; } +static int gpioline_config_change_validate(struct line *line, + struct gpioline_config *lc) +{ + int i; + u64 flags; + struct gpio_desc *desc; + + for (i = 0; i < line->num_descs; i++) { + desc = line->descs[i]; + flags = gpioline_config_flags(lc, i); + /* disallow edge detection changes */ + if (line->edets[i].flags != (flags & GPIOLINE_EDGE_FLAGS)) + return -EINVAL; + + if (line->edets[i].flags) { + /* disallow polarity changes */ + if (test_bit(FLAG_ACTIVE_LOW, &desc->flags) != + ((flags & GPIOLINE_FLAG_V2_ACTIVE_LOW) != 0)) + return -EINVAL; + } + } + return 0; +} + static void gpioline_config_flags_to_desc_flags(u64 flags, unsigned long *flagsp) { @@ -757,6 +785,66 @@ static long line_get_values(struct line *line, void __user *ip) return 0; } +static long line_set_config_locked(struct line *line, + struct gpioline_config *lc) +{ + struct gpio_desc *desc; + int i, ret; + u64 flags; + + ret = gpioline_config_change_validate(line, lc); + if (ret) + return ret; + + for (i = 0; i < line->num_descs; i++) { + desc = line->descs[i]; + flags = gpioline_config_flags(lc, i); + + gpioline_config_flags_to_desc_flags(flags, &desc->flags); + /* + * Lines have to be requested explicitly for input + * or output, else the line will be treated "as is". + */ + if (flags & GPIOLINE_FLAG_V2_OUTPUT) { + int val = gpioline_config_output_value(lc, i); + + edge_detector_stop(&line->edets[i]); + ret = gpiod_direction_output(desc, val); + if (ret) + return ret; + } else if (flags & GPIOLINE_FLAG_V2_INPUT) { + ret = gpiod_direction_input(desc); + if (ret) + return ret; + } + + blocking_notifier_call_chain(&desc->gdev->notifier, + GPIOLINE_CHANGED_CONFIG, desc); + } + return 0; +} + +static long line_set_config(struct line *line, void __user *ip) +{ + struct gpioline_config lc; + int ret; + + if (copy_from_user(&lc, ip, sizeof(lc))) + return -EFAULT; + + ret = gpioline_config_validate(&lc, line->num_descs); + if (ret) + return ret; + + mutex_lock(&line->config_mutex); + + ret = line_set_config_locked(line, &lc); + + mutex_unlock(&line->config_mutex); + + return ret; +} + static long line_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -765,6 +853,8 @@ static long line_ioctl(struct file *file, unsigned int cmd, if (cmd == GPIOLINE_GET_VALUES_IOCTL) return line_get_values(line, ip); + else if (cmd == GPIOLINE_SET_CONFIG_IOCTL) + return line_set_config(line, ip); return -EINVAL; } @@ -937,6 +1027,7 @@ static int line_create(struct gpio_device *gdev, void __user *ip) } } + mutex_init(&line->config_mutex); init_waitqueue_head(&line->wait); if (has_edge_detection) { size = linereq.event_buffer_size; -- 2.27.0