From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 0E15BC32789 for ; Sun, 4 Nov 2018 13:53:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BDFF12085A for ; Sun, 4 Nov 2018 13:53:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="KtQ9tLko" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BDFF12085A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730892AbeKDXIM (ORCPT ); Sun, 4 Nov 2018 18:08:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:46634 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730857AbeKDXIL (ORCPT ); Sun, 4 Nov 2018 18:08:11 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 23F0C2085A; Sun, 4 Nov 2018 13:53:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541339586; bh=4+I+CLzE6apcN8eMCgqp2O/9v9nYaWnGsicZecBtHvY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KtQ9tLko8mfwUY+vIfpcDJjA7zxv9SYii8qdSdPdf/TOCIHrjLBVsC+qWuBu6P0BP Y5xLEHkpvq57rvFI1khO1zvRkjbMc9KZNiJOSqK6xFnG2SCNRgwQ6OrymzyDECz+NR cXhJbQ04yBRuYtwns/KP8FI9LZpLbvpmmFxAh1/c= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Eugen Hristev , Maxime Ripard , Stable@vger.kernel.org, Jonathan Cameron , Sasha Levin Subject: [PATCH AUTOSEL 4.18 25/45] iio: adc: at91: fix acking DRDY irq on simple conversions Date: Sun, 4 Nov 2018 08:52:20 -0500 Message-Id: <20181104135240.88431-25-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181104135240.88431-1-sashal@kernel.org> References: <20181104135240.88431-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eugen Hristev [ Upstream commit bc1b45326223e7e890053cf6266357adfa61942d ] When doing simple conversions, the driver did not acknowledge the DRDY irq. If this irq status is not acked, it will be left pending, and as soon as a trigger is enabled, the irq handler will be called, it doesn't know why this status has occurred because no channel is pending, and then it will go int a irq loop and board will hang. To avoid this situation, read the LCDR after a raw conversion is done. Fixes: 0e589d5fb ("ARM: AT91: IIO: Add AT91 ADC driver.") Cc: Maxime Ripard Signed-off-by: Eugen Hristev Acked-by: Ludovic Desroches Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- drivers/iio/adc/at91_adc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c index 91c250ae0437..75d2f73582a3 100644 --- a/drivers/iio/adc/at91_adc.c +++ b/drivers/iio/adc/at91_adc.c @@ -281,6 +281,8 @@ static void handle_adc_eoc_trigger(int irq, struct iio_dev *idev) iio_trigger_poll(idev->trig); } else { st->last_value = at91_adc_readl(st, AT91_ADC_CHAN(st, st->chnb)); + /* Needed to ACK the DRDY interruption */ + at91_adc_readl(st, AT91_ADC_LCDR); st->done = true; wake_up_interruptible(&st->wq_data_avail); } -- 2.17.1