From patchwork Thu Mar 9 06:53:26 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heiner Kallweit X-Patchwork-Id: 736850 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3vf1kl4gKjz9sNK for ; Thu, 9 Mar 2017 18:10:39 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="Ttu8Y4lH"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752158AbdCIHKj (ORCPT ); Thu, 9 Mar 2017 02:10:39 -0500 Received: from mail-wr0-f194.google.com ([209.85.128.194]:34687 "EHLO mail-wr0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751798AbdCIHKi (ORCPT ); Thu, 9 Mar 2017 02:10:38 -0500 Received: by mail-wr0-f194.google.com with SMTP id u48so6764877wrc.1 for ; Wed, 08 Mar 2017 23:10:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:cc:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding; bh=wFrYZArYZrq/GVpBxdbA1syA26xRdRdpjMadXOfgWUE=; b=Ttu8Y4lHeb85EKsntigfsbCQ3Nvq5TbbW5cj/Z+aJyBgfSo9G82sFG1bXLnW0aJfN8 cKKEUWJy0sNNR22phUepWh8561KGeDNBiM4+tt7vskysAnWE+oqS1yGQLfkdTgmTF+TX cntruSH8VXXEyxZ3pZOiLRPUjytw/ePQMMFmCCyT7q5hHpa+kFEaPkPiNPmg57V61fZz SAlujVdKRsGb07Dgi3vaC2gV9Twpw6XZWiXqx9FKQUUsf5xPXACU5Ioto3iDOmaQlCLy SNGpM4Oxp2mjBKe6kfMr25/aRUGzt7aVd5aljgMSsr9hwC3q4pWggzznXYYyg2p7TMdK FfbQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=wFrYZArYZrq/GVpBxdbA1syA26xRdRdpjMadXOfgWUE=; b=SjDF87/u9m5+MPPl2JF+zxXJSp9E7dY9Jrqz0tV7m+ThQ7tRHNQPoWN43cvh3RDsA1 umwBxqBD9IOVraWudUYoy2DFLpjkq2gLKCXwhNZ9jsD+dFIzv0QW5q+rbZ2FscW6JFFS rRRo5E32my27kQyHNY+JPMde9pDS9McN6TBvz+d7NpWZpR/r36HixBUD8FQ6UQhytX/w OctaAO+lhtKeB3lIauDSSSvqH4PGVmMRt8uPhu5CCe5UC9SVRH7vdcGjiQ/IDDXZxmBc LIU27UNDvpQpOmL6SishCg+kO68UZA8EXSE8iCCBvEXG2YFKrE35cSE+PFEkKKQse3ss /18g== X-Gm-Message-State: AMke39mV+n1CO8aJd8St0FNY/VN2m56tvwiqnLKdIzPK9Uh196UfJKX595UoXkDLQZdaqQ== X-Received: by 10.223.170.73 with SMTP id q9mr8955825wrd.13.1489042907295; Wed, 08 Mar 2017 23:01:47 -0800 (PST) Received: from ?IPv6:2003:c6:ebdc:4000:b589:624b:5134:aa75? (p200300C6EBDC4000B589624B5134AA75.dip0.t-ipconnect.de. [2003:c6:ebdc:4000:b589:624b:5134:aa75]) by smtp.googlemail.com with ESMTPSA id v1sm6976432wra.65.2017.03.08.23.01.46 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 08 Mar 2017 23:01:46 -0800 (PST) Subject: [PATCH v2 07/10] i2c: meson: improve interrupt handler and detect spurious interrupts To: Wolfram Sang , Jerome Brunet References: Cc: "linux-i2c@vger.kernel.org" , linux-amlogic@lists.infradead.org From: Heiner Kallweit Message-ID: <372c966f-253d-fdd0-9675-6f928e02d401@gmail.com> Date: Thu, 9 Mar 2017 07:53:26 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org If state is STATE_IDLE no interrupt should occur. Detect this case and warn. In addition move resetting REG_CTRL_START bit to the start of the interrupt handler and remove a unneeded REG_CTRL_START bit reset in meson_i2c_xfer_msg. Signed-off-by: Heiner Kallweit --- v2: - don't print an error if spurious interrupt is detected --- drivers/i2c/busses/i2c-meson.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c index 56e15a74..74d433cd 100644 --- a/drivers/i2c/busses/i2c-meson.c +++ b/drivers/i2c/busses/i2c-meson.c @@ -228,12 +228,18 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id) spin_lock(&i2c->lock); meson_i2c_reset_tokens(i2c); + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); ctrl = readl(i2c->regs + REG_CTRL); dev_dbg(i2c->dev, "irq: state %d, pos %d, count %d, ctrl %08x\n", i2c->state, i2c->pos, i2c->count, ctrl); - if (ctrl & REG_CTRL_ERROR && i2c->state != STATE_IDLE) { + if (i2c->state == STATE_IDLE) { + spin_unlock(&i2c->lock); + return IRQ_NONE; + } + + if (ctrl & REG_CTRL_ERROR) { /* * The bit is set when the IGNORE_NAK bit is cleared * and the device didn't respond. In this case, the @@ -276,15 +282,12 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id) i2c->state = STATE_IDLE; complete(&i2c->done); break; - case STATE_IDLE: - break; } out: if (i2c->state != STATE_IDLE) { /* Restart the processing */ meson_i2c_write_tokens(i2c); - meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, REG_CTRL_START); } @@ -344,9 +347,6 @@ static int meson_i2c_xfer_msg(struct meson_i2c *i2c, struct i2c_msg *msg, */ spin_lock_irqsave(&i2c->lock, flags); - /* Abort any active operation */ - meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); - if (!time_left) { i2c->state = STATE_IDLE; ret = -ETIMEDOUT;