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 94780C32789 for ; Sun, 4 Nov 2018 13:54:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5420B2085B for ; Sun, 4 Nov 2018 13:54:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="UznGhPC3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5420B2085B 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 S1731916AbeKDXJu (ORCPT ); Sun, 4 Nov 2018 18:09:50 -0500 Received: from mail.kernel.org ([198.145.29.99]:49888 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731865AbeKDXJr (ORCPT ); Sun, 4 Nov 2018 18:09:47 -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 438402085B; Sun, 4 Nov 2018 13:54:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541339683; bh=6gYR4gGK9rsu1OC9TK1WBf4LnxVhVTmnFQ/de0i/EFA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UznGhPC35REw19UF2AxTyp+CBQfKnIb8uCC4VriYmokayqrT1qSXWPiwMjh3PnH1a iNPQHZcfw/+zrWOWVVzoYItv14IEBXrH9IcUB5MbWcgdHzOIf6Gy+0NAO01dKeSg0X Ztk0lYBfUPA9wEaYeQYJRli1kjRR+n+3TyJt3kj4= 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 3.18 08/13] iio: adc: at91: fix acking DRDY irq on simple conversions Date: Sun, 4 Nov 2018 08:54:28 -0500 Message-Id: <20181104135433.88734-8-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181104135433.88734-1-sashal@kernel.org> References: <20181104135433.88734-1-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 8dc9f442c796..dc438141b75b 100644 --- a/drivers/iio/adc/at91_adc.c +++ b/drivers/iio/adc/at91_adc.c @@ -278,6 +278,8 @@ 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