From patchwork Wed Jul 10 16:23:13 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roger Quadros X-Patchwork-Id: 2825824 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 0DF9EC0AB2 for ; Wed, 10 Jul 2013 16:26:01 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id E62F1201C7 for ; Wed, 10 Jul 2013 16:25:59 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 135EF201C4 for ; Wed, 10 Jul 2013 16:25:58 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UwxBU-0005DW-CO; Wed, 10 Jul 2013 16:24:05 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UwxB9-0001TK-TP; Wed, 10 Jul 2013 16:23:43 +0000 Received: from arroyo.ext.ti.com ([192.94.94.40]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UwxB3-0001R9-SV for linux-arm-kernel@lists.infradead.org; Wed, 10 Jul 2013 16:23:39 +0000 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id r6AGNHKq006191; Wed, 10 Jul 2013 11:23:17 -0500 Received: from DLEE70.ent.ti.com (dlee70.ent.ti.com [157.170.170.113]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r6AGNHPl016289; Wed, 10 Jul 2013 11:23:17 -0500 Received: from dlelxv22.itg.ti.com (172.17.1.197) by DLEE70.ent.ti.com (157.170.170.113) with Microsoft SMTP Server id 14.2.342.3; Wed, 10 Jul 2013 11:23:17 -0500 Received: from localhost.localdomain (h0-150.vpn.ti.com [172.24.0.150]) by dlelxv22.itg.ti.com (8.13.8/8.13.8) with ESMTP id r6AGNEMZ010139; Wed, 10 Jul 2013 11:23:15 -0500 From: Roger Quadros To: Subject: [PATCH 5/6] USB: Support wakeup IRQ for suspended controllers Date: Wed, 10 Jul 2013 19:23:13 +0300 Message-ID: <1373473393-27552-1-git-send-email-rogerq@ti.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1373473081-27181-1-git-send-email-rogerq@ti.com> References: <1373473081-27181-1-git-send-email-rogerq@ti.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130710_122338_060260_B2125319 X-CRM114-Status: GOOD ( 15.59 ) X-Spam-Score: -7.2 (-------) Cc: khilman@linaro.org, sergei.shtylyov@cogentembedded.com, tony@atomide.com, gregkh@linuxfoundation.org, ruslan.bilovol@ti.com, linux-kernel@vger.kernel.org, balbi@ti.com, linux-usb@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Roger Quadros X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Some platforms e.g. ehci-omap can generate an interrupt (i.e. remote wakeup) even when the controller is suspended i.e. HW_ACCESSIBLE is cleared. Introduce a flag "has_wakeup_irq" in struct usb_hcd to indicate such cases. We tackle this case by disabling the IRQ, scheduling a hub resume and enabling back the IRQ after the controller has resumed. This ensures that the IRQ handler runs only after the controller is accessible. Signed-off-by: Roger Quadros --- drivers/usb/core/hcd.c | 21 ++++++++++++++++++++- include/linux/usb/hcd.h | 3 +++ 2 files changed, 23 insertions(+), 1 deletions(-) diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 014dc99..933d8f1 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2161,6 +2161,11 @@ static void hcd_resume_work(struct work_struct *work) usb_lock_device(udev); usb_remote_wakeup(udev); usb_unlock_device(udev); + if (HCD_IRQ_DISABLED(hcd)) { + /* We can now process IRQs so enable IRQ */ + clear_bit(HCD_FLAG_IRQ_DISABLED, &hcd->flags); + enable_irq(hcd->irq); + } } /** @@ -2248,7 +2253,21 @@ irqreturn_t usb_hcd_irq (int irq, void *__hcd) */ local_irq_save(flags); - if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd))) + if (unlikely(HCD_DEAD(hcd))) + rc = IRQ_NONE; + else if (unlikely(!HCD_HW_ACCESSIBLE(hcd) && hcd->has_wakeup_irq)) { + /* + * We got a wakeup interrupt while the controller was + * suspending or suspended. We can't handle it now, so + * disable the IRQ and resume the root hub (and hence + * the controller too). + */ + disable_irq_nosync(hcd->irq); + set_bit(HCD_FLAG_IRQ_DISABLED, &hcd->flags); + usb_hcd_resume_root_hub(hcd); + + rc = IRQ_HANDLED; + } else if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) rc = IRQ_NONE; else if (hcd->driver->irq(hcd) == IRQ_NONE) rc = IRQ_NONE; diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h index 1e88377..5eb9f85 100644 --- a/include/linux/usb/hcd.h +++ b/include/linux/usb/hcd.h @@ -110,6 +110,7 @@ struct usb_hcd { #define HCD_FLAG_WAKEUP_PENDING 4 /* root hub is resuming? */ #define HCD_FLAG_RH_RUNNING 5 /* root hub is running? */ #define HCD_FLAG_DEAD 6 /* controller has died? */ +#define HCD_FLAG_IRQ_DISABLED 7 /* Interrupt was disabled */ /* The flags can be tested using these macros; they are likely to * be slightly faster than test_bit(). @@ -120,6 +121,7 @@ struct usb_hcd { #define HCD_WAKEUP_PENDING(hcd) ((hcd)->flags & (1U << HCD_FLAG_WAKEUP_PENDING)) #define HCD_RH_RUNNING(hcd) ((hcd)->flags & (1U << HCD_FLAG_RH_RUNNING)) #define HCD_DEAD(hcd) ((hcd)->flags & (1U << HCD_FLAG_DEAD)) +#define HCD_IRQ_DISABLED(hcd) ((hcd)->flags & (1U << HCD_FLAG_IRQ_DISABLED)) /* Flags that get set only during HCD registration or removal. */ unsigned rh_registered:1;/* is root hub registered? */ @@ -132,6 +134,7 @@ struct usb_hcd { unsigned wireless:1; /* Wireless USB HCD */ unsigned authorized_default:1; unsigned has_tt:1; /* Integrated TT in root hub */ + unsigned has_wakeup_irq:1; /* Can IRQ when suspended */ unsigned int irq; /* irq allocated */ void __iomem *regs; /* device memory/io */