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,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 68368C432C3 for ; Fri, 22 Nov 2019 10:31:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3F5B92071B for ; Fri, 22 Nov 2019 10:31:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574418671; bh=WiBksml3Di1WYFYiOQH1mulf+M8x8gaNtPvMG683ctI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=qQI9IWi/f3A0MFlysAb2NUTu2COQHldxE+2CLsL2RtSSoy447AvYIQisgrIYkUz8s K1So6zJf/K9aE7NNOvAlaCklKCmlh4Ckua644uhmR09V0GUY6a+cCK5SQJvJeek8oK VXzhAz2YJDQ03nquW/8QWP5crGsPRxb/MR8QM6/k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727171AbfKVKbK (ORCPT ); Fri, 22 Nov 2019 05:31:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:50956 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727113AbfKVKbI (ORCPT ); Fri, 22 Nov 2019 05:31:08 -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 B106020708; Fri, 22 Nov 2019 10:31:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574418668; bh=WiBksml3Di1WYFYiOQH1mulf+M8x8gaNtPvMG683ctI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=StY2qZclZgjg8KoYf/QV2jZDqxS6YGOtJa8Mlo4Vzzyd+EFQemZt+0WQcaZJXUEpY evDfxinV/T6Xm3zH9cMs0+68LcShqBDlSb2619yROYJZ90YeNut+wtrGJsI/qvIY0l 5Eb3Kv4WEiO6BmikZHLg1C54IViXfzD4FowMkdIw= 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 4.4 012/159] iio: dac: mcp4922: fix error handling in mcp4922_write_raw Date: Fri, 22 Nov 2019 11:26:43 +0100 Message-Id: <20191122100718.354014416@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191122100704.194776704@linuxfoundation.org> References: <20191122100704.194776704@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 3854d201a5d6c..68dd0be1ac076 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