From patchwork Tue Feb 24 09:56:02 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris BREZILLON X-Patchwork-Id: 5871221 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 [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 79E34BF440 for ; Tue, 24 Feb 2015 09:59:42 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 937E320662 for ; Tue, 24 Feb 2015 09:59:41 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0DA0120650 for ; Tue, 24 Feb 2015 09:59:40 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YQCF6-0007dd-1f; Tue, 24 Feb 2015 09:57:28 +0000 Received: from down.free-electrons.com ([37.187.137.238] helo=mail.free-electrons.com) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YQCEC-0007EN-TI for linux-arm-kernel@lists.infradead.org; Tue, 24 Feb 2015 09:56:34 +0000 Received: by mail.free-electrons.com (Postfix, from userid 106) id A786E3D0; Tue, 24 Feb 2015 10:56:21 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from localhost.localdomain (col31-4-88-188-83-94.fbx.proxad.net [88.188.83.94]) by mail.free-electrons.com (Postfix) with ESMTPSA id EEDD85EF; Tue, 24 Feb 2015 10:56:20 +0100 (CET) From: Boris Brezillon To: Thomas Gleixner , Jason Cooper , "Rafael J. Wysocki" , Peter Zijlstra , Mark Rutland Subject: [RFC PATCH 3/3] rtc: at91sam9: properly act when IRQ handler is called in suspended state Date: Tue, 24 Feb 2015 10:56:02 +0100 Message-Id: <1424771762-16343-4-git-send-email-boris.brezillon@free-electrons.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1424771762-16343-1-git-send-email-boris.brezillon@free-electrons.com> References: <1424771762-16343-1-git-send-email-boris.brezillon@free-electrons.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150224_015633_304188_89EB414A X-CRM114-Status: GOOD ( 16.01 ) X-Spam-Score: 1.0 (+) Cc: Boris Brezillon , Nicolas Ferre , linux-kernel@vger.kernel.org, Alexandre Belloni , Jean-Christophe Plagniol-Villard , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The IRQ line used by the RTC device is often shared with the system timer (PIT) on at91 platforms. Since timers are registering their handlers with IRQF_NO_SUSPEND, we should expect being called in suspended state, and properly wake the system up when this is the case. Signed-off-by: Boris Brezillon --- drivers/rtc/rtc-at91sam9.c | 62 ++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 51 insertions(+), 11 deletions(-) diff --git a/drivers/rtc/rtc-at91sam9.c b/drivers/rtc/rtc-at91sam9.c index 2183fd2..8cf9c1b 100644 --- a/drivers/rtc/rtc-at91sam9.c +++ b/drivers/rtc/rtc-at91sam9.c @@ -77,6 +77,8 @@ struct sam9_rtc { unsigned int gpbr_offset; int irq; struct clk *sclk; + unsigned long events; + spinlock_t lock; }; #define rtt_readl(rtc, field) \ @@ -271,14 +273,9 @@ static int at91_rtc_proc(struct device *dev, struct seq_file *seq) return 0; } -/* - * IRQ handler for the RTC - */ -static irqreturn_t at91_rtc_interrupt(int irq, void *_rtc) +static irqreturn_t at91_rtc_cache_events(struct sam9_rtc *rtc) { - struct sam9_rtc *rtc = _rtc; u32 sr, mr; - unsigned long events = 0; /* Shared interrupt may be for another device. Note: reading * SR clears it, so we must only read it in this irq handler! @@ -290,18 +287,54 @@ static irqreturn_t at91_rtc_interrupt(int irq, void *_rtc) /* alarm status */ if (sr & AT91_RTT_ALMS) - events |= (RTC_AF | RTC_IRQF); + rtc->events |= (RTC_AF | RTC_IRQF); /* timer update/increment */ if (sr & AT91_RTT_RTTINC) - events |= (RTC_UF | RTC_IRQF); + rtc->events |= (RTC_UF | RTC_IRQF); + + return IRQ_HANDLED; +} + +static void at91_rtc_flush_events(struct sam9_rtc *rtc) +{ + if (!rtc->events) + return; - rtc_update_irq(rtc->rtcdev, 1, events); + rtc_update_irq(rtc->rtcdev, 1, rtc->events); + rtc->events = 0; pr_debug("%s: num=%ld, events=0x%02lx\n", __func__, - events >> 8, events & 0x000000FF); + rtc->events >> 8, rtc->events & 0x000000FF); +} - return IRQ_HANDLED; +/* + * IRQ handler for the RTC + */ +static irqreturn_t at91_rtc_interrupt(int irq, void *_rtc) +{ + struct sam9_rtc *rtc = _rtc; + int ret; + + spin_lock(&rtc->lock); + + ret = at91_rtc_cache_events(rtc); + + /* We're called in suspended state */ + if (irq_is_wakeup_armed(irq)) { + /* Mask irqs coming from this peripheral */ + rtt_writel(rtc, MR, + rtt_readl(rtc, MR) & + ~(AT91_RTT_ALMIEN | AT91_RTT_RTTINCIEN)); + /* Trigger a system wakeup */ + irq_pm_force_wakeup(); + } else { + at91_rtc_flush_events(rtc); + } + + spin_unlock(&rtc->lock); + + return ret; } static const struct rtc_class_ops at91_rtc_ops = { @@ -499,10 +532,17 @@ static int at91_rtc_resume(struct device *dev) u32 mr; if (rtc->imr) { + unsigned long flags; + if (device_may_wakeup(dev)) disable_irq_wake(rtc->irq); mr = rtt_readl(rtc, MR); rtt_writel(rtc, MR, mr | rtc->imr); + + spin_lock_irqsave(&rtc->lock, flags); + at91_rtc_cache_events(rtc); + at91_rtc_flush_events(rtc); + spin_unlock_irqrestore(&rtc->lock, flags); } return 0;