From patchwork Wed Apr 16 07:28:37 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Horman X-Patchwork-Id: 3998711 Return-Path: X-Original-To: patchwork-ltsi-dev@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 3A1F5BFF02 for ; Wed, 16 Apr 2014 07:28:53 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5D27620211 for ; Wed, 16 Apr 2014 07:28:52 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) by mail.kernel.org (Postfix) with ESMTP id 5C90720268 for ; Wed, 16 Apr 2014 07:28:51 +0000 (UTC) Received: from mail.linux-foundation.org (localhost [IPv6:::1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 76CFB87D; Wed, 16 Apr 2014 07:28:49 +0000 (UTC) X-Original-To: ltsi-dev@lists.linuxfoundation.org Delivered-To: ltsi-dev@mail.linuxfoundation.org Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTP id AE3D3875 for ; Wed, 16 Apr 2014 07:28:47 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from kirsty.vergenet.net (kirsty.vergenet.net [202.4.237.240]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 52A801FA26 for ; Wed, 16 Apr 2014 07:28:46 +0000 (UTC) Received: from ayumi.isobedori.kobe.vergenet.net (p2020-ipbfp1604kobeminato.hyogo.ocn.ne.jp [114.154.85.20]) by kirsty.vergenet.net (Postfix) with ESMTP id D640925BE51; Wed, 16 Apr 2014 17:28:42 +1000 (EST) Received: by ayumi.isobedori.kobe.vergenet.net (Postfix, from userid 7100) id 9EB06EDE63A; Wed, 16 Apr 2014 16:28:42 +0900 (JST) From: Simon Horman To: ltsi-dev@lists.linuxfoundation.org Date: Wed, 16 Apr 2014 16:28:37 +0900 Message-Id: <1397633319-16727-2-git-send-email-horms+renesas@verge.net.au> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1397633319-16727-1-git-send-email-horms+renesas@verge.net.au> References: <1397633319-16727-1-git-send-email-horms+renesas@verge.net.au> X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,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 Cc: Magnus Damm Subject: [LTSI-dev] [PATCH 1/3] gpio: rcar: Fix level interrupt handling X-BeenThere: ltsi-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: "A list to discuss patches, development, and other things related to the LTSI project" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: ltsi-dev-bounces@lists.linuxfoundation.org Errors-To: ltsi-dev-bounces@lists.linuxfoundation.org X-Virus-Scanned: ClamAV using ClamSMTP From: Valentine Barshak According to the manual, if a port is set for level detection using the corresponding bit in the edge/level select register and an external level interrupt signal is asserted, the corresponding bit in INTDT does not use the FF to hold the input. Thus, writing 1 to the corresponding bits in INTCLR cannot clear the corresponding bits in the INTDT register. Instead, when an external input signal is stopped, the corresponding bit in INTDT is cleared automatically. Since the INTDT bit cannot be cleared for the level interrupts until the interrupt signal is stopped, we end up with the infinite loop when using deferred (threaded) IRQ handling. Since a deferred interrupt is disabled by the low-level handler and re-enabled only when the deferred handler is completed, Fix the issue by dropping disabled interrupts from the pending mask as suggested by Laurent Pinchart Changes in V2: * Drop disabled interrupts from pending mask altogether instead of dropping level interrupts one by one once they get handled. Signed-off-by: Valentine Barshak Acked-by: Laurent Pinchart Acked-by: Magnus Damm Signed-off-by: Linus Walleij (cherry picked from commit 8808b64daac68a2c85366c767a3ef850824ede74) Signed-off-by: Simon Horman --- drivers/gpio/gpio-rcar.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpio/gpio-rcar.c b/drivers/gpio/gpio-rcar.c index 9ed7921..bbb0df2 100644 --- a/drivers/gpio/gpio-rcar.c +++ b/drivers/gpio/gpio-rcar.c @@ -169,7 +169,8 @@ static irqreturn_t gpio_rcar_irq_handler(int irq, void *dev_id) u32 pending; unsigned int offset, irqs_handled = 0; - while ((pending = gpio_rcar_read(p, INTDT))) { + while ((pending = gpio_rcar_read(p, INTDT) & + gpio_rcar_read(p, INTMSK))) { offset = __ffs(pending); gpio_rcar_write(p, INTCLR, BIT(offset)); generic_handle_irq(irq_find_mapping(p->irq_domain, offset));