From patchwork Tue Sep 11 09:42:15 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shubhrajyoti Datta X-Patchwork-Id: 1436831 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork2.kernel.org (Postfix) with ESMTP id E83A6DFAF3 for ; Tue, 11 Sep 2012 09:56:13 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TBN7n-0003vr-Jm; Tue, 11 Sep 2012 09:51:20 +0000 Received: from arroyo.ext.ti.com ([192.94.94.40]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TBN01-0006fD-LS for linux-arm-kernel@lists.infradead.org; Tue, 11 Sep 2012 09:43:22 +0000 Received: from dbdp20.itg.ti.com ([172.24.170.38]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id q8B9gql1015014; Tue, 11 Sep 2012 04:42:53 -0500 Received: from DBDE71.ent.ti.com (localhost [127.0.0.1]) by dbdp20.itg.ti.com (8.13.8/8.13.8) with ESMTP id q8B9gqgV009210; Tue, 11 Sep 2012 15:12:52 +0530 (IST) Received: from dbdp32.itg.ti.com (172.24.170.251) by DBDE71.ent.ti.com (172.24.170.149) with Microsoft SMTP Server id 14.1.323.3; Tue, 11 Sep 2012 15:12:52 +0530 Received: from ula0393217.india.ti.com (smtpvbd.itg.ti.com [172.24.170.250]) by dbdp32.itg.ti.com (8.13.8/8.13.8) with ESMTP id q8B9gKDi010282; Tue, 11 Sep 2012 15:12:51 +0530 From: Shubhrajyoti D To: Subject: [PATCHv7 20/23] i2c: omap: switch to threaded IRQ support Date: Tue, 11 Sep 2012 15:12:15 +0530 Message-ID: <1347356538-23835-21-git-send-email-shubhrajyoti@ti.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1347356538-23835-1-git-send-email-shubhrajyoti@ti.com> References: <1347356538-23835-1-git-send-email-shubhrajyoti@ti.com> MIME-Version: 1.0 X-Spam-Note: CRM114 invocation failed X-Spam-Score: -7.3 (-------) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-7.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [192.94.94.40 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.4 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: tony@atomide.com, w.sang@pengutronix.de, Felipe Balbi , linux-i2c@vger.kernel.org, ben-linux@fluff.org, Shubhrajyoti D , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Felipe Balbi for OMAP2, we can easily switch over to threaded IRQs on the I2C driver. This will allow us to spend less time in hardirq context. Signed-off-by: Felipe Balbi [Trivial formating changes] Signed-off-by: Shubhrajyoti D --- drivers/i2c/busses/i2c-omap.c | 43 +++++++++++++++++++++++++++++++++++----- 1 files changed, 37 insertions(+), 6 deletions(-) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 4a696bd..e391370 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -176,6 +176,7 @@ enum { #define I2C_OMAP_ERRATA_I462 (1 << 1) struct omap_i2c_dev { + spinlock_t lock; /* IRQ synchronization */ struct device *dev; void __iomem *base; /* virtual */ int irq; @@ -854,9 +855,30 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes, } static irqreturn_t -omap_i2c_isr(int this_irq, void *dev_id) +omap_i2c_isr(int irq, void *dev_id) { struct omap_i2c_dev *dev = dev_id; + irqreturn_t ret = IRQ_HANDLED; + u16 mask; + u16 stat; + + spin_lock(&dev->lock); + mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); + stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); + + if (stat & mask) + ret = IRQ_WAKE_THREAD; + + spin_unlock(&dev->lock); + + return ret; +} + +static irqreturn_t +omap_i2c_isr_thread(int this_irq, void *dev_id) +{ + struct omap_i2c_dev *dev = dev_id; + unsigned long flags; u16 bits; u16 stat; int err = 0, count = 0; @@ -864,6 +886,7 @@ omap_i2c_isr(int this_irq, void *dev_id) if (pm_runtime_suspended(dev->dev)) return IRQ_HANDLED; + spin_lock_irqsave(&dev->lock, flags); do { bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); @@ -877,6 +900,7 @@ omap_i2c_isr(int this_irq, void *dev_id) if (!stat) { /* my work here is done */ + spin_unlock_irqrestore(&dev->lock, flags); return IRQ_HANDLED; } @@ -985,6 +1009,8 @@ omap_i2c_isr(int this_irq, void *dev_id) out: omap_i2c_complete_cmd(dev, err); + spin_unlock_irqrestore(&dev->lock, flags); + return IRQ_HANDLED; } @@ -1028,7 +1054,6 @@ omap_i2c_probe(struct platform_device *pdev) struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data; struct device_node *node = pdev->dev.of_node; const struct of_device_id *match; - irq_handler_t isr; int irq; int r; @@ -1078,6 +1103,8 @@ omap_i2c_probe(struct platform_device *pdev) dev->dev = &pdev->dev; dev->irq = irq; + spin_lock_init(&dev->lock); + platform_set_drvdata(pdev, dev); init_completion(&dev->cmd_complete); @@ -1130,10 +1157,14 @@ omap_i2c_probe(struct platform_device *pdev) /* reset ASAP, clearing any IRQs */ omap_i2c_init(dev); - isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr : - omap_i2c_isr; - r = devm_request_irq(&pdev->dev, dev->irq, isr, IRQF_NO_SUSPEND, - pdev->name, dev); + if (dev->rev < OMAP_I2C_OMAP1_REV_2) + r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr, + IRQF_NO_SUSPEND, pdev->name, dev); + else + r = devm_request_threaded_irq(&pdev->dev, dev->irq, + omap_i2c_isr, omap_i2c_isr_thread, + IRQF_NO_SUSPEND | IRQF_ONESHOT, + pdev->name, dev); if (r) { dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);