From patchwork Wed Jan 10 13:17:39 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anup Patel X-Patchwork-Id: 10155149 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 3E30160231 for ; Wed, 10 Jan 2018 13:18:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2EBDC27F94 for ; Wed, 10 Jan 2018 13:18:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2317828497; Wed, 10 Jan 2018 13:18:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 78FC727F94 for ; Wed, 10 Jan 2018 13:18:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754728AbeAJNR4 (ORCPT ); Wed, 10 Jan 2018 08:17:56 -0500 Received: from mail-pl0-f65.google.com ([209.85.160.65]:44102 "EHLO mail-pl0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754725AbeAJNRx (ORCPT ); Wed, 10 Jan 2018 08:17:53 -0500 Received: by mail-pl0-f65.google.com with SMTP id n13so7241381plp.11 for ; Wed, 10 Jan 2018 05:17:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=brainfault-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id; bh=6zTqz1Y1Apo8M7jtwRT5ptOLuDbChu7BJZa4Zhs1stM=; b=ezbxbEVvQTeYdLVkWfhW/TCyqLHqidY4LAJw6HvHXRvH2c6A1ro52nPuiCzXPn1eWF Hvg0Sjg5Mg5pKz+q7q1whQ6Bym5nwaDhh4po+axLsBn2fwtIutMRuT4MH0vR5RaMRk4w s+2M4C/iO+AdHIxTC0aQzt3tdr1roJ/K2/9K2YJsX7aQePCA8txav3xzRZ+a8vDA6PHK i2YrO//zMImNkvnX4/4Ud7cohuO15LFNOYEz+btc4ipQhoC5PATk8pXHD1ML+/+wP0BI S5+iIn2ywvpsl+a62b8licQLYpS23uXcKOysxZJ8bywGMxmIx3Lqh9GFB60cXZUZwti0 Rt+w== 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; bh=6zTqz1Y1Apo8M7jtwRT5ptOLuDbChu7BJZa4Zhs1stM=; b=qX5Lc4vk/smSzlPU82kl+smCX3AIrQ0xNiTwM/29ZCzLeTlt6KNnBCfbAUhc/eb4Ml FFN/g4jlwTeCCaK5PYmFawEctE6xKzA1EkeZw0z/RHWjiZMnqLElBfpvgavRwfZwu7eg KNGf752eX3iBy6UnO3JBp9YsyOb9C3GUBnXbrveVbFq2Jq/FYQFzV9tCbDAxkxhttV5F iPxcNl3BrTMYIJfuwa4OD5t+HnbQnucim7dY6o8ATjvW4jzP26koDivYmDNq3o2ix5pM szPmQsuzMz3yOn9T5FawF0xUfPXdKBIzQBkbitOiY6FPJXWAlSsjfomTQlLtP2jk2egi t9LA== X-Gm-Message-State: AKGB3mJtGUl/VJU5I0dC0ud9BB2moM+3zvvzoR5+XIi/xR8OjVJuW+40 bfJ4kT/Vvf4E8CFAp8iPg9fc6Q/u X-Google-Smtp-Source: ACJfBovSshpWGJhJCTjLUdo7FqsccFIEONmOgxWMRP1rVh3zQBjDDw7ByLwNGKWENnbiIyiz4TRMKw== X-Received: by 10.159.204.146 with SMTP id t18mr13345186plo.352.1515590273164; Wed, 10 Jan 2018 05:17:53 -0800 (PST) Received: from anup-ubuntu64.dlink.router ([122.171.99.18]) by smtp.googlemail.com with ESMTPSA id y7sm35184924pfy.96.2018.01.10.05.17.49 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 10 Jan 2018 05:17:52 -0800 (PST) From: Anup Patel To: Ohad Ben-Cohen , Bjorn Andersson Cc: linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, Anup Patel Subject: [PATCH RESEND] rpmsg: Add driver_override device attribute for rpmsg_device Date: Wed, 10 Jan 2018 18:47:39 +0530 Message-Id: <1515590259-24304-1-git-send-email-anup@brainfault.org> X-Mailer: git-send-email 2.7.4 Sender: linux-remoteproc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-remoteproc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds "driver_override" device attribute for rpmsg_device which will allow users to explicitly specify the rpmsg_driver to be used via sysfs entry. The "driver_override" device attribute implemented here is very similar to "driver_override" implemented for platform, pci, and amba bus types. One important use-case of "driver_override" device attribute is to force use of rpmsg_chrdev driver for certain rpmsg_device instances. Signed-off-by: Anup Patel --- Documentation/ABI/testing/sysfs-bus-rpmsg | 20 ++++++++++++++ drivers/rpmsg/rpmsg_core.c | 46 +++++++++++++++++++++++++++++-- 2 files changed, 64 insertions(+), 2 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-bus-rpmsg b/Documentation/ABI/testing/sysfs-bus-rpmsg index 189e419..1c8599e 100644 --- a/Documentation/ABI/testing/sysfs-bus-rpmsg +++ b/Documentation/ABI/testing/sysfs-bus-rpmsg @@ -73,3 +73,23 @@ Description: This sysfs entry tells us whether the channel is a local server channel that is announced (values are either true or false). + +What: /sys/bus/rpmsg/devices/.../driver_override +Date: January 2018 +KernelVersion: 4.16 +Contact: Ohad Ben-Cohen +Description: + Every rpmsg device is a communication channel with a remote + processor. Channels are identified by a textual name (see + /sys/bus/rpmsg/devices/.../name above) and have a local + ("source") rpmsg address, and remote ("destination") rpmsg + address. + + The listening entity (or client) which communicates with a + remote processor is referred as rpmsg driver. The rpmsg device + and rpmsg driver are matched based on rpmsg device name and + rpmsg driver ID table. + + This sysfs entry allows the rpmsg driver for a rpmsg device + to be specified which will override standard OF, ID table + and name matching. diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c index dffa3aa..9a25e42 100644 --- a/drivers/rpmsg/rpmsg_core.c +++ b/drivers/rpmsg/rpmsg_core.c @@ -321,11 +321,11 @@ struct device *rpmsg_find_device(struct device *parent, } EXPORT_SYMBOL(rpmsg_find_device); -/* sysfs show configuration fields */ +/* sysfs configuration fields */ #define rpmsg_show_attr(field, path, format_string) \ static ssize_t \ field##_show(struct device *dev, \ - struct device_attribute *attr, char *buf) \ + struct device_attribute *attr, char *buf) \ { \ struct rpmsg_device *rpdev = to_rpmsg_device(dev); \ \ @@ -333,11 +333,52 @@ field##_show(struct device *dev, \ } \ static DEVICE_ATTR_RO(field); +#define rpmsg_string_attr(field, path) \ +static ssize_t \ +field##_store(struct device *dev, \ + struct device_attribute *attr, const char *buf, size_t sz)\ +{ \ + struct rpmsg_device *rpdev = to_rpmsg_device(dev); \ + char *new, *old, *cp; \ + \ + new = kstrndup(buf, sz, GFP_KERNEL); \ + if (!new) \ + return -ENOMEM; \ + \ + cp = strchr(new, '\n'); \ + if (cp) \ + *cp = '\0'; \ + \ + device_lock(dev); \ + old = rpdev->path; \ + if (strlen(new)) { \ + rpdev->path = new; \ + } else { \ + kfree(new); \ + rpdev->path = NULL; \ + } \ + device_unlock(dev); \ + \ + kfree(old); \ + \ + return sz; \ +} \ +static ssize_t \ +field##_show(struct device *dev, \ + struct device_attribute *attr, char *buf) \ +{ \ + struct rpmsg_device *rpdev = to_rpmsg_device(dev); \ + \ + return sprintf(buf, "%s\n", rpdev->path); \ +} \ +static DEVICE_ATTR_RW(field) + /* for more info, see Documentation/ABI/testing/sysfs-bus-rpmsg */ rpmsg_show_attr(name, id.name, "%s\n"); rpmsg_show_attr(src, src, "0x%x\n"); rpmsg_show_attr(dst, dst, "0x%x\n"); rpmsg_show_attr(announce, announce ? "true" : "false", "%s\n"); +rpmsg_string_attr(driver_override, driver_override); static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -359,6 +400,7 @@ static struct attribute *rpmsg_dev_attrs[] = { &dev_attr_dst.attr, &dev_attr_src.attr, &dev_attr_announce.attr, + &dev_attr_driver_override.attr, NULL, }; ATTRIBUTE_GROUPS(rpmsg_dev);