From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966330AbcIVRpQ (ORCPT ); Thu, 22 Sep 2016 13:45:16 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:57254 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966283AbcIVRpC (ORCPT ); Thu, 22 Sep 2016 13:45:02 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vignesh R , Lee Jones , Jonathan Cameron Subject: [PATCH 4.7 071/184] iio: adc: ti_am335x_adc: Increase timeout value waiting for ADC sample Date: Thu, 22 Sep 2016 19:40:05 +0200 Message-Id: <20160922174051.753520254@linuxfoundation.org> X-Mailer: git-send-email 2.10.0 In-Reply-To: <20160922174048.653794923@linuxfoundation.org> References: <20160922174048.653794923@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vignesh R commit 7175cce1c3f1d8c8840d2004f78f96a3904249b5 upstream. Now that open delay and sample delay for each channel is configurable via DT, the default IDLE_TIMEOUT value is not enough as this is calculated based on hardcoded macros. This results in driver returning EBUSY sometimes. Fix this by increasing the timeout value based on maximum value possible to open delay and sample delays for each channel. Fixes: 5dc11e810676e ("iio: adc: ti_am335x_adc: make sample delay, open delay, averaging DT parameters") Signed-off-by: Vignesh R Acked-by: Lee Jones Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- drivers/iio/adc/ti_am335x_adc.c | 2 +- include/linux/mfd/ti_am335x_tscadc.h | 8 ++++---- 2 files changed, 5 insertions(+), 5 deletions(-) --- a/drivers/iio/adc/ti_am335x_adc.c +++ b/drivers/iio/adc/ti_am335x_adc.c @@ -382,7 +382,7 @@ static int tiadc_read_raw(struct iio_dev am335x_tsc_se_set_once(adc_dev->mfd_tscadc, step_en); - timeout = jiffies + usecs_to_jiffies + timeout = jiffies + msecs_to_jiffies (IDLE_TIMEOUT * adc_dev->channels); /* Wait for Fifo threshold interrupt */ while (1) { --- a/include/linux/mfd/ti_am335x_tscadc.h +++ b/include/linux/mfd/ti_am335x_tscadc.h @@ -138,16 +138,16 @@ /* * time in us for processing a single channel, calculated as follows: * - * num cycles = open delay + (sample delay + conv time) * averaging + * max num cycles = open delay + (sample delay + conv time) * averaging * - * num cycles: 152 + (1 + 13) * 16 = 376 + * max num cycles: 262143 + (255 + 13) * 16 = 266431 * * clock frequency: 26MHz / 8 = 3.25MHz * clock period: 1 / 3.25MHz = 308ns * - * processing time: 376 * 308ns = 116us + * max processing time: 266431 * 308ns = 83ms(approx) */ -#define IDLE_TIMEOUT 116 /* microsec */ +#define IDLE_TIMEOUT 83 /* milliseconds */ #define TSCADC_CELLS 2