From patchwork Tue Apr 28 18:24:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 226792 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8801C83007 for ; Tue, 28 Apr 2020 18:52:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 98C9220730 for ; Tue, 28 Apr 2020 18:52:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588099941; bh=44T7SWIY83Obrz2DWLQSdXGRagyEww4zB2z4m9v9SEk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mKPyerjBiTtQ5RtBS4yczShzNy/rCHE0HjFgk24edK83xFKIKOnQSKdY/Ach1pgJf IAwtNMxTB3ofQjkMbexr6AE/uuxFb4eFjVWLmNE4vnoIJLKqx06n1NjuvLWubknl+T WzBQA1kyShIlffFnq4+0Cn4a5mxboM3bxrz7vx18= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729579AbgD1SwV (ORCPT ); Tue, 28 Apr 2020 14:52:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:53654 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730364AbgD1SgQ (ORCPT ); Tue, 28 Apr 2020 14:36:16 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E7EB020575; Tue, 28 Apr 2020 18:36:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588098976; bh=44T7SWIY83Obrz2DWLQSdXGRagyEww4zB2z4m9v9SEk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VX3B2fC4PBnGPwgzUnUBYc4Vsoor1+mtqGUOP4ism2iCeq7YrKpyO8FTJFmxgCKcP 4eAbMXRAtVpqPwyFxoXzp0k9KSA+6WQavK35rMzAqjcxEjOW/1NbErrEvEa/B720dH 407cY9nqq6UAzC5XIArDDrZlzaOhx7B4U41kwJn0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lars-Peter Clausen , Stable@vger.kernel.org, Jonathan Cameron Subject: [PATCH 4.19 081/131] iio: xilinx-xadc: Fix clearing interrupt when enabling trigger Date: Tue, 28 Apr 2020 20:24:53 +0200 Message-Id: <20200428182235.120764718@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200428182224.822179290@linuxfoundation.org> References: <20200428182224.822179290@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Lars-Peter Clausen commit f954b098fbac4d183219ce5b42d76d6df2aed50a upstream. When enabling the trigger and unmasking the end-of-sequence (EOS) interrupt the EOS interrupt should be cleared from the status register. Otherwise it is possible that it was still set from a previous capture. If that is the case the interrupt would fire immediately even though no conversion has been done yet and stale data is being read from the device. The old code only clears the interrupt if the interrupt was previously unmasked. Which does not make much sense since the interrupt is always masked at this point and in addition masking the interrupt does not clear the interrupt from the status register. So the clearing needs to be done unconditionally. Signed-off-by: Lars-Peter Clausen Fixes: bdc8cda1d010 ("iio:adc: Add Xilinx XADC driver") Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- drivers/iio/adc/xilinx-xadc-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/iio/adc/xilinx-xadc-core.c +++ b/drivers/iio/adc/xilinx-xadc-core.c @@ -675,7 +675,7 @@ static int xadc_trigger_set_state(struct spin_lock_irqsave(&xadc->lock, flags); xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val); - xadc_write_reg(xadc, XADC_AXI_REG_IPISR, val & XADC_AXI_INT_EOS); + xadc_write_reg(xadc, XADC_AXI_REG_IPISR, XADC_AXI_INT_EOS); if (state) val |= XADC_AXI_INT_EOS; else