From patchwork Tue Jan 30 06:47:13 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guan-Yu Lin X-Patchwork-Id: 193861 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:7301:2087:b0:106:209c:c626 with SMTP id gs7csp1038959dyb; Mon, 29 Jan 2024 22:49:56 -0800 (PST) X-Google-Smtp-Source: AGHT+IGiT5IcUwmteGd2shgsx5bmZjWGjp/4qgm4nhTdU8W5rZr4oBzlccSLbtDV+n1G+Aj3S+Fc X-Received: by 2002:a05:622a:14d:b0:42a:68d4:a576 with SMTP id v13-20020a05622a014d00b0042a68d4a576mr7299754qtw.137.1706597396142; Mon, 29 Jan 2024 22:49:56 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1706597396; cv=pass; d=google.com; s=arc-20160816; b=BuTFVzqLw2xLyTRWHVa8/M7+5vwJzWZv513yTZ52DCrfa1PWtkIZxOzM3bnFKnSVls +dpdWXUbbAdCXEQRJhSQMT8DdSysqAPRzjYyJ5KcNytXG5wkWc73bWwHbMe5YfnmDZIf dAgQloShe9i8t/7UfXOcJGZDpiTltObvh19P3MhXC+s5ZuONyp9mCVTmh2ednHdf72f6 8ShEucpBFa4QGYV/lx9Bzww+ZBtarcnRAKkGJ8OiSgfFDB/QvvV6IFlp0D6usCzgowJI Os0t4nUj+WTlC2FZfQ4EtmrjsQXPIUHr4IFlApTysfLQns/+X+95wck3cOb5hxjv4j6T hzGQ== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=cc:to:from:subject:message-id:mime-version:list-unsubscribe :list-subscribe:list-id:precedence:date:dkim-signature; bh=0kJpyZRLEun0ampJIfj1X21WJ21b9jsbskmJbElfrgM=; fh=1/0E41JAPFqtqqWX4/Bsg5zqsTrgiF9Qm+Cx1Os57Uk=; b=wZZ7TUkavVjBrMFb/FrXWjcnyxMlkdoDgBH/Uox5aVO+d/QlJVdTrguIa2F89pngp+ QlNyXWyP9abCpmsf/ekl5fbDGIAvvweUn3QsIJqtVib/rh98T/Mv4cDnGPBwNSmD8h9n UCCUuKmyPESNpKOSz2XTgSscB1YTVFTjkdVryU+2M0354Byqtkh3CyEccMZsP8W4VTHv VkEtQ8zR+IyEv+EWQ6EVee9y3hVxW1rBZMEuMJcImN+TCzKH83yOm92niWvG6rM8z2to 5IrFW1N1iV3NDCSW3MXE2rO/j1idttbKpQXOKIuQPcOVB4VsfZhUQkr0jIWtDbFvj82d SBhA== ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=eYC2M3eF; arc=pass (i=1 spf=pass spfdomain=flex--guanyulin.bounces.google.com dkim=pass dkdomain=google.com dmarc=pass fromdomain=google.com); spf=pass (google.com: domain of linux-kernel+bounces-44010-ouuuleilei=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) smtp.mailfrom="linux-kernel+bounces-44010-ouuuleilei=gmail.com@vger.kernel.org"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from ny.mirrors.kernel.org (ny.mirrors.kernel.org. [147.75.199.223]) by mx.google.com with ESMTPS id v1-20020ae9e301000000b00783f8128b54si4899510qkf.352.2024.01.29.22.49.56 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 29 Jan 2024 22:49:56 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-44010-ouuuleilei=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=eYC2M3eF; arc=pass (i=1 spf=pass spfdomain=flex--guanyulin.bounces.google.com dkim=pass dkdomain=google.com dmarc=pass fromdomain=google.com); spf=pass (google.com: domain of linux-kernel+bounces-44010-ouuuleilei=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) smtp.mailfrom="linux-kernel+bounces-44010-ouuuleilei=gmail.com@vger.kernel.org"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ny.mirrors.kernel.org (Postfix) with ESMTPS id C8BEB1C219DB for ; Tue, 30 Jan 2024 06:49:55 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B66ED51C38; Tue, 30 Jan 2024 06:49:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="eYC2M3eF" Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7EDCC39879 for ; Tue, 30 Jan 2024 06:49:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706597370; cv=none; b=kzAN6RK1fXBjFjux3uEiP0QmNQ1pNjorGkLT8tNqq8wzypic0vSomxerK1SwfEL7SMJfNqhoXizvstbvMM4buOCLEiPC8TjXCgfe67RaIbW3AV2NGHDBYthDfFi9GTfa238/0mIC7POGCwLNLg4QN0f4zEMIHbxxOvUzy4B/6Fs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706597370; c=relaxed/simple; bh=F677IBoUhHzMTuvWXqwcPdgWDOJp521cNnxnaG/vMiM=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=HPylqKdw5iRnURNNZce9LVsWe49b9jFRTkwwiyNn1uJVDH6+dWrExiVfyUfD2/4RWFRca8IW5s2SpA5Yb58BM6jl8LugLLd7slwc/7C/lXmjcqdyikd/9nLH7yoUP6lcOlKvXWR3ZAJCCZd53/NARsx2tYE+VsBzkcMjI3iNcrU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--guanyulin.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=eYC2M3eF; arc=none smtp.client-ip=209.85.219.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--guanyulin.bounces.google.com Received: by mail-yb1-f202.google.com with SMTP id 3f1490d57ef6-dbe9e13775aso5762412276.1 for ; Mon, 29 Jan 2024 22:49:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1706597367; x=1707202167; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=0kJpyZRLEun0ampJIfj1X21WJ21b9jsbskmJbElfrgM=; b=eYC2M3eFPEOfG+smc9aFGfTkPI3tlUcxF9DEyL+NkZqXhxBG7Pn5MZsPLCDUy8YOHA K6PI9gejBBDWuCfpA9rSkPiA+b52atjnTS8r1vi+3JeAyfTFMV7mi4kyISEJoIaCLFXv 0yu0dDImyHSKzpLSA5eHq+xwHeMfx02hibxyoKI1gYqf/7Taz6j2N9HG3lBuCbE4VxlH YvpuGQjhQ+r0pY0e3Oibr2xJS3Toq/Iqb00kuiLkRXgIA5xpzXk8NhbI3GvhC3xOAFj2 pIkrlNxmktQ6iPotU+SF1wbvs/9CITAleFef5cYBZSOcDBY+CT5QFGmRgFZ/5Awp+4af wIzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706597367; x=1707202167; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=0kJpyZRLEun0ampJIfj1X21WJ21b9jsbskmJbElfrgM=; b=PH7FTMXcI4u6j5UsoQosX120yeze2lCLkgs2sX7xbE56EQbeLh8J3r4C0JaHXcn2JP nKOiBsXAkCb/brxHH66fEsUzQJrkH+yjEURITr+aPWdyVJa4DExSIRmr6Nu3UOAjMlfY qh2/zPR0QD5fTsgve03N7aS9joCmmgxsNzYOWogRKUQjuNcbLLRGAwGeVDt1zJouGAli Atj2+kb/JXyYkHRNkwPIY6mYpkN0GpKjBYemN6pxFebT3h64uxJy3tRp2OO/NeBW1lky quIsQ48fkkO7TNO8HCqC/Mgikdh6x+57YhQlKa6ej0lB1Srv5Zo6N/K0QRoFEBNksq8l niaQ== X-Gm-Message-State: AOJu0YwC56eDYssifuFrunX2XxcVMZ+v1DAD7+bbr/QfZ4PENXedmlMl nO0iQrwxO3tcRtS/wDqtjWeScSCpAsUUa4ONW+Gs4djtWU5xhLDfsdkA2y3bNHXQr1WLO7mmOXU ZgOtXfwfduF7sRA== X-Received: from guanyulin.c.googlers.com ([fda3:e722:ac3:cc00:3:22c1:c0a8:1af]) (user=guanyulin job=sendgmr) by 2002:a05:6902:108f:b0:dc2:23d8:722d with SMTP id v15-20020a056902108f00b00dc223d8722dmr2784786ybu.13.1706597367593; Mon, 29 Jan 2024 22:49:27 -0800 (PST) Date: Tue, 30 Jan 2024 06:47:13 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.43.0.429.g432eaa2c6b-goog Message-ID: <20240130064819.1362642-1-guanyulin@google.com> Subject: [PATCH] [RFC] usb: host: Allow userspace to control usb suspend flows From: Guan-Yu Lin To: gregkh@linuxfoundation.org, mathias.nyman@intel.com, stern@rowland.harvard.edu, royluo@google.com, hadess@hadess.net, benjamin.tissoires@redhat.com, heikki.krogerus@linux.intel.com, oneukum@suse.com, grundler@chromium.org, yajun.deng@linux.dev, dianders@chromium.org Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, badhri@google.com, albertccwang@google.com, pumahsu@google.com, Guan-Yu Lin X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1789497071531348381 X-GMAIL-MSGID: 1789497071531348381 In a system with sub-system engaged, the controllers are controlled by both the main processor and the co-processor. Chances are when the main processor decides to suspend the USB device, the USB device might still be used by the co-processor. In this scenario, we need a way to let system know whether it can suspend the USB device or not. We introduce a new sysfs entry "deprecate_device_pm" to allow userspace to control the device power management functionality on demand. As the userspace should possess the information of both the main processor and the co-processor, it should be able to address the conflict mentioned above. Signed-off-by: Guan-Yu Lin --- Documentation/ABI/testing/sysfs-bus-usb | 10 +++++++++ drivers/usb/core/driver.c | 18 ++++++++++++++++ drivers/usb/core/sysfs.c | 28 +++++++++++++++++++++++++ drivers/usb/host/xhci-plat.c | 20 ++++++++++++++++++ include/linux/usb.h | 4 ++++ 5 files changed, 80 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index 2b7108e21977..3f3d6c14201f 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb @@ -19,6 +19,16 @@ Description: would be authorized by default. The value can be 1 or 0. It's by default 1. +What: /sys/bus/usb/devices/usbX/deprecate_device_pm +Date: January 2024 +Contact: Guan-Yu Lin +Description: + Deprecates the device power management functionality of USB devices + and their host contorller under this usb bus. The modification of + this entry should be done when the system is active to ensure the + correctness of system power state transitions. + The value can be 1 or 0. It's by default 0. + What: /sys/bus/usb/device/.../authorized Date: July 2008 KernelVersion: 2.6.26 diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index e02ba15f6e34..e03cf972160d 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -1569,6 +1569,15 @@ int usb_suspend(struct device *dev, pm_message_t msg) struct usb_device *udev = to_usb_device(dev); int r; + /* + * Skip the entire suspend process under the same usb bus if its sysfs + * entry `deprecate_device_pm` is set. + */ + if (udev->bus->deprecate_device_pm) { + dev_vdbg(&udev->dev, "deprecating dev_pm_ops: %s\n", __func__); + return 0; + } + unbind_no_pm_drivers_interfaces(udev); /* From now on we are sure all drivers support suspend/resume @@ -1605,6 +1614,15 @@ int usb_resume(struct device *dev, pm_message_t msg) struct usb_device *udev = to_usb_device(dev); int status; + /* + * Skip the entire resume process under the same usb bus if its sysfs + * entry `deprecate_device_pm` is set. + */ + if (udev->bus->deprecate_device_pm) { + dev_vdbg(&udev->dev, "deprecating dev_pm_ops: %s\n", __func__); + return 0; + } + /* For all calls, take the device back to full power and * tell the PM core in case it was autosuspended previously. * Unbind the interfaces that will need rebinding later, diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c index 5d21718afb05..b4520e5c8974 100644 --- a/drivers/usb/core/sysfs.c +++ b/drivers/usb/core/sysfs.c @@ -68,6 +68,33 @@ static ssize_t bMaxPower_show(struct device *dev, } static DEVICE_ATTR_RO(bMaxPower); +static ssize_t deprecate_device_pm_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct usb_device *udev; + + udev = to_usb_device(dev); + return sysfs_emit(buf, "%d\n", !!(udev->bus->deprecate_device_pm)); +} + +static ssize_t deprecate_device_pm_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct usb_device *udev = to_usb_device(dev); + int val, rc; + + if (sscanf(buf, "%d", &val) != 1 || val < 0 || val > 1) + return -EINVAL; + rc = usb_lock_device_interruptible(udev); + if (rc < 0) + return -EINTR; + udev->bus->deprecate_device_pm = !!(val); + usb_unlock_device(udev); + return count; +} +static DEVICE_ATTR_RW(deprecate_device_pm); + static ssize_t configuration_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -984,6 +1011,7 @@ static DEVICE_ATTR_RW(interface_authorized_default); static struct attribute *usb_bus_attrs[] = { &dev_attr_authorized_default.attr, &dev_attr_interface_authorized_default.attr, + &dev_attr_deprecate_device_pm.attr, NULL, }; diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c index f04fde19f551..bc05d83d1c0b 100644 --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -442,6 +442,15 @@ static int xhci_plat_suspend(struct device *dev) struct xhci_hcd *xhci = hcd_to_xhci(hcd); int ret; + /* + * Skip the entire suspend process under the same usb bus if its sysfs + * entry `deprecate_device_pm` is set. + */ + if (hcd->self.deprecate_device_pm) { + dev_vdbg(dev, "deprecating dev_pm_ops: %s\n", __func__); + return 0; + } + if (pm_runtime_suspended(dev)) pm_runtime_resume(dev); @@ -507,6 +516,17 @@ static int xhci_plat_resume_common(struct device *dev, struct pm_message pmsg) static int xhci_plat_resume(struct device *dev) { + struct usb_hcd *hcd = dev_get_drvdata(dev); + + /* + * Skip the entire resume process under the same usb bus if its sysfs + * entry `deprecate_device_pm` is set. + */ + if (hcd->self.deprecate_device_pm) { + dev_vdbg(dev, "deprecating dev_pm_ops: %s\n", __func__); + return 0; + } + return xhci_plat_resume_common(dev, PMSG_RESUME); } diff --git a/include/linux/usb.h b/include/linux/usb.h index 9e52179872a5..1a1873104663 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -465,6 +465,10 @@ struct usb_bus { * the ep queue on a short transfer * with the URB_SHORT_NOT_OK flag set. */ + unsigned deprecate_device_pm:1; /* Deprecates the device power management + * functionality of USB devices on this + * bus and their hcd. + */ unsigned no_sg_constraint:1; /* no sg constraint */ unsigned sg_tablesize; /* 0 or largest number of sg list entries */