From patchwork Mon Jan 1 12:31:18 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anup Patel X-Patchwork-Id: 10138537 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 7DC846035E for ; Mon, 1 Jan 2018 12:31:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6EBE028811 for ; Mon, 1 Jan 2018 12:31:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 63D6428813; Mon, 1 Jan 2018 12:31:37 +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=ham 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 D844128811 for ; Mon, 1 Jan 2018 12:31:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751258AbeAAMbf (ORCPT ); Mon, 1 Jan 2018 07:31:35 -0500 Received: from mail-pg0-f65.google.com ([74.125.83.65]:37991 "EHLO mail-pg0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751231AbeAAMbe (ORCPT ); Mon, 1 Jan 2018 07:31:34 -0500 Received: by mail-pg0-f65.google.com with SMTP id t67so1642018pgc.5 for ; Mon, 01 Jan 2018 04:31:33 -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=xoVoi+WjnmTrm8lx6TZpOgKZBuumXvR8KXbnqS7/t5OF6vmmeZizQrmPu7V5XdQMVl ITp5OFSkaDK8kx4+yps2gpwKSUE/GOQgyEHFGROPYlMbmZMAjOAc8fq8FEkpgtogs+Kg 1My3EKGlfz4BZfbz0MmQlV+07F2pmFVQ+YFt8uhhqqVtDaE3MH/sKuhf5QqGAlZfUnhU CpmoYHqaqINp64uDdbDVWJXinQwAqe/46K4mIQAV48CBOhaTYBlrK0BEyxKTNgfdE2qF RRagkrN83XEoSzggjG1xM0JZQroBrPlBYgyRFcR3lA0LKtc8+vk9N10kaynE8g5MvZ0X VXBQ== 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=T7aQ878DEkVF+53tRILldMaeUyamqc3B4qEtVrCC+2Tk6q1mlJfTVKdywKDwp+azkO i4rr/0DfhYTAcgeiFzh8tymjunAj7XfbENYRYBUIVTtXfM/J0pjhkovh/UjMtJDwRnvB cwIEweI7G0qVVKwVgr+5klIOmUun8/7Pg/AZajTj+OoDFBksV6dfeHUdSkVfnacd3OTa SeaUstkYD477/DVCRbrE1S6KP4SCQv/qbDq5HusOfLts61blLmbupYUs2XgTsavNPrvn 0X4SE7dCV/LVdO43AG7SFixcOWCcMbmcA/VxEx7Y5wtJAqAGNcIImbRkLlExsBfP9swi UElA== X-Gm-Message-State: AKGB3mK1jTqTAiYv0dBx5LCYwMa5n5wsXBM/LdHUxEEezjgvJjbK5NUj kHpCHQa2DTKbqNztxRa2ryIGMw== X-Google-Smtp-Source: ACJfBosvFjUZNvaR8R5D4aBu44+/cRtHhgw5A4XauRYIeoi9yMxtcWPyAqFq+q7aSrqbPFx4GALsbA== X-Received: by 10.99.151.66 with SMTP id d2mr9844383pgo.245.1514809893443; Mon, 01 Jan 2018 04:31:33 -0800 (PST) Received: from anup-ubuntu64.dlink.router ([122.171.119.106]) by smtp.googlemail.com with ESMTPSA id s65sm89268961pfk.7.2018.01.01.04.31.30 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 01 Jan 2018 04:31:32 -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] rpmsg: Add driver_override device attribute for rpmsg_device Date: Mon, 1 Jan 2018 18:01:18 +0530 Message-Id: <1514809878-28521-1-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);