From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753049AbcGYTjP (ORCPT ); Mon, 25 Jul 2016 15:39:15 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:55955 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751105AbcGYTjM (ORCPT ); Mon, 25 Jul 2016 15:39:12 -0400 From: Guenter Roeck To: Jonathan Cameron Cc: Heiko Stuebner , linux-iio@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, Caesar Wang , dianders@chromium.org, Guenter Roeck Subject: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe Date: Mon, 25 Jul 2016 12:39:00 -0700 Message-Id: <1469475540-26855-1-git-send-email-linux@roeck-us.net> X-Mailer: git-send-email 2.5.0 X-Authenticated_sender: guenter@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: guenter@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: guenter@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the ADC is read for the first time, the caller gets a timeout error, and the kernel log shows read channel() error: -110 The ADC may be enabled on boot, and needs to be explicitly disabled for a read sequence to work (otherwise there is no completion interrupt). Disaple it explicitly in the probe function. Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc") Signed-off-by: Guenter Roeck --- drivers/iio/adc/rockchip_saradc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c index f9ad6c2d6821..6aa3271d86b5 100644 --- a/drivers/iio/adc/rockchip_saradc.c +++ b/drivers/iio/adc/rockchip_saradc.c @@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct platform_device *pdev) goto err_pclk; } + /* Make sure ADC is disabled */ + writel_relaxed(0, info->regs + SARADC_CTRL); + platform_set_drvdata(pdev, indio_dev); indio_dev->name = dev_name(&pdev->dev); -- 2.5.0