From patchwork Wed Apr 1 16:17:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 228414 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, 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 AEC76C2D0F2 for ; Wed, 1 Apr 2020 16:41:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 80EE2206F8 for ; Wed, 1 Apr 2020 16:41:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585759314; bh=Qv7p7skIwClAgWc94R84u6lXFzPtN2mlav+yyCBP6S0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=GtFR8qk/y8cQhaMmxKyEiJv33fo+1d24tOWqyQzcGYwx674kvTuQ8O579BY+0VggX bUORAP/fceh2NCJd43DAIMjAWqqB3nLszIEsvmh0EEO522mDX6YdtCmMZupqmDjMyf N8T3VF0ESRst+w9t4bIlIJ7pIV+X4F2ngnmljaPg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389456AbgDAQlw (ORCPT ); Wed, 1 Apr 2020 12:41:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:42356 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389162AbgDAQlw (ORCPT ); Wed, 1 Apr 2020 12:41:52 -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 C062420658; Wed, 1 Apr 2020 16:41:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585759311; bh=Qv7p7skIwClAgWc94R84u6lXFzPtN2mlav+yyCBP6S0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C97YkYsttPnp+UemRo9gWCLI9JIJzJKI+ExrjjNkNKtepdkAkvF9bkiRtghTTI/CD qx78FeHSDC4ZL2cNq/KuihiKqGSBjFh75pxf8IlbRw2KAvh1jpr3eqwRxFAiLrqSCd dKh6xc7p7skrys9WcCV8glxM8+Z87RTH5A7EcvHk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eugen Hristev , Stable@vger.kernel.org, Jonathan Cameron , Sasha Levin Subject: [PATCH 4.14 042/148] iio: adc: at91-sama5d2_adc: fix channel configuration for differential channels Date: Wed, 1 Apr 2020 18:17:14 +0200 Message-Id: <20200401161556.877865168@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200401161552.245876366@linuxfoundation.org> References: <20200401161552.245876366@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: Eugen Hristev [ Upstream commit f0c8d1f6dc8eac5a1fbf441c8e080721a7b6c0ff ] When iterating through the channels, the index in the array is not the scan index. Added an xlate function to translate to the proper index. The result of the bug is that the channel array is indexed with a wrong index, thus instead of the proper channel, we access invalid memory, which may lead to invalid results and/or corruption. This will be used also for devicetree channel xlate. Fixes: 5e1a1da0f ("iio: adc: at91-sama5d2_adc: add hw trigger and buffer support") Fixes: 073c66201 ("iio: adc: at91-sama5d2_adc: add support for DMA") Signed-off-by: Eugen Hristev Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- drivers/iio/adc/at91-sama5d2_adc.c | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-) diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c index a70ef7fec95f0..0898f40c2b892 100644 --- a/drivers/iio/adc/at91-sama5d2_adc.c +++ b/drivers/iio/adc/at91-sama5d2_adc.c @@ -300,6 +300,27 @@ static const struct iio_chan_spec at91_adc_channels[] = { + AT91_SAMA5D2_DIFF_CHAN_CNT + 1), }; +static int at91_adc_chan_xlate(struct iio_dev *indio_dev, int chan) +{ + int i; + + for (i = 0; i < indio_dev->num_channels; i++) { + if (indio_dev->channels[i].scan_index == chan) + return i; + } + return -EINVAL; +} + +static inline struct iio_chan_spec const * +at91_adc_chan_get(struct iio_dev *indio_dev, int chan) +{ + int index = at91_adc_chan_xlate(indio_dev, chan); + + if (index < 0) + return NULL; + return indio_dev->channels + index; +} + static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state) { struct iio_dev *indio = iio_trigger_get_drvdata(trig); @@ -317,8 +338,10 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state) at91_adc_writel(st, AT91_SAMA5D2_TRGR, status); for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) { - struct iio_chan_spec const *chan = indio->channels + bit; + struct iio_chan_spec const *chan = at91_adc_chan_get(indio, bit); + if (!chan) + continue; if (state) { at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel)); @@ -398,8 +421,11 @@ static irqreturn_t at91_adc_trigger_handler(int irq, void *p) u8 bit; for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) { - struct iio_chan_spec const *chan = indio->channels + bit; + struct iio_chan_spec const *chan = + at91_adc_chan_get(indio, bit); + if (!chan) + continue; st->buffer[i] = at91_adc_readl(st, chan->address); i++; }