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=-9.8 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,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 A3BB9C432C0 for ; Tue, 19 Nov 2019 05:24:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7452422309 for ; Tue, 19 Nov 2019 05:24:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574141080; bh=MeTFZGRJid8ZbNeiR81q23RkFona0u2IvdbdJMDE4Yo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=h2iPrlt1BjAAAENGsYRjxWKY28iCT0TWf7/gZYlWwtuV8PvnFhITq/LiSg3wxEEeg XJHSExx+XJRjlbmXMXD1rzYH+LQIPjt6eDLKuN0xOEbt28z9uS1NOHKU32ZOTedzg1 MiW6NxavHvk+2hdW54ifJtWyW/qRDG+1wgExixag= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728236AbfKSFYi (ORCPT ); Tue, 19 Nov 2019 00:24:38 -0500 Received: from mail.kernel.org ([198.145.29.99]:40854 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728221AbfKSFYf (ORCPT ); Tue, 19 Nov 2019 00:24:35 -0500 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 763B221783; Tue, 19 Nov 2019 05:24:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574141075; bh=MeTFZGRJid8ZbNeiR81q23RkFona0u2IvdbdJMDE4Yo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sbKEbXUu70aAQrCKXbDr1OWf1ALo/KNaR3Xn2W6Raiy3ldWds1oM/zRrv3kMNgJO8 qmrnuqrC0AhSRGI2GLetqO61/UDgDufG0JVApwdoUhEAQGFDRqqJZAgrItWAUD15JN L0X95wckdsPSa9HO/XkTYpyW4lt8+5jUbexUJr+k= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marcus Folkesson , Jonathan Cameron , Sasha Levin Subject: [PATCH 4.19 036/422] iio: dac: mcp4922: fix error handling in mcp4922_write_raw Date: Tue, 19 Nov 2019 06:13:53 +0100 Message-Id: <20191119051402.331301983@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191119051400.261610025@linuxfoundation.org> References: <20191119051400.261610025@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marcus Folkesson [ Upstream commit 0833627fc3f757a0dca11e2a9c46c96335a900ee ] Do not try to write negative values and make sure that the write goes well. Signed-off-by: Marcus Folkesson Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- drivers/iio/dac/mcp4922.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/iio/dac/mcp4922.c b/drivers/iio/dac/mcp4922.c index bf9aa3fc0534e..b5190d1dae8e3 100644 --- a/drivers/iio/dac/mcp4922.c +++ b/drivers/iio/dac/mcp4922.c @@ -94,17 +94,22 @@ static int mcp4922_write_raw(struct iio_dev *indio_dev, long mask) { struct mcp4922_state *state = iio_priv(indio_dev); + int ret; if (val2 != 0) return -EINVAL; switch (mask) { case IIO_CHAN_INFO_RAW: - if (val > GENMASK(chan->scan_type.realbits-1, 0)) + if (val < 0 || val > GENMASK(chan->scan_type.realbits - 1, 0)) return -EINVAL; val <<= chan->scan_type.shift; - state->value[chan->channel] = val; - return mcp4922_spi_write(state, chan->channel, val); + + ret = mcp4922_spi_write(state, chan->channel, val); + if (!ret) + state->value[chan->channel] = val; + return ret; + default: return -EINVAL; } -- 2.20.1