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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE3F7C433EF for ; Mon, 13 Jun 2022 10:19:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235726AbiFMKT0 (ORCPT ); Mon, 13 Jun 2022 06:19:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60786 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241532AbiFMKSQ (ORCPT ); Mon, 13 Jun 2022 06:18:16 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3F19DDEE6; Mon, 13 Jun 2022 03:16:04 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C4DB66144E; Mon, 13 Jun 2022 10:16:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D4000C36B00; Mon, 13 Jun 2022 10:16:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655115363; bh=o5D8cWAzSpLX6Ke+wFetopA+FTG86p/iMfzrOLTRMdw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zo1Wfuabo+HIpEjdd73GvgHzu9Y80Hj1ZlP7pDx81W64hGxZYgJk4Mjm5X2CqOgbW GFvRORcsl/eP8gQvcAv9ESgnjTEZsgsQt09huBhwdBaIrh1r/hL7xt0QXLQF764AN5 y61DO499AIcuELoggTKMY4q7vP/cuOjoatFoscak= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Dmitry Baryshkov , Abhinav Kumar , Marijn Suijten , Sasha Levin Subject: [PATCH 4.9 047/167] drm/msm/dsi: fix error checks and return values for DSI xmit functions Date: Mon, 13 Jun 2022 12:08:41 +0200 Message-Id: <20220613094851.997240070@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094840.720778945@linuxfoundation.org> References: <20220613094840.720778945@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dmitry Baryshkov [ Upstream commit f0e7e9ed379c012c4d6b09a09b868accc426223c ] As noticed by Dan ([1] an the followup thread) there are multiple issues with the return values for MSM DSI command transmission callback. In the error case it can easily return a positive value when it should have returned a proper error code. This commits attempts to fix these issues both in TX and in RX paths. [1]: https://lore.kernel.org/linux-arm-msm/20211001123617.GH2283@kili/ Fixes: a689554ba6ed ("drm/msm: Initial add DSI connector support") Reported-by: Dan Carpenter Signed-off-by: Dmitry Baryshkov Reviewed-by: Abhinav Kumar Tested-by: Marijn Suijten Patchwork: https://patchwork.freedesktop.org/patch/480501/ Link: https://lore.kernel.org/r/20220401231104.967193-1-dmitry.baryshkov@linaro.org Signed-off-by: Dmitry Baryshkov Signed-off-by: Sasha Levin --- drivers/gpu/drm/msm/dsi/dsi_host.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c index 246336a9f47d..bea4969900ab 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -1240,10 +1240,10 @@ static int dsi_cmds2buf_tx(struct msm_dsi_host *msm_host, dsi_get_bpp(msm_host->format) / 8; len = dsi_cmd_dma_add(msm_host, msg); - if (!len) { + if (len < 0) { pr_err("%s: failed to add cmd type = 0x%x\n", __func__, msg->type); - return -EINVAL; + return len; } /* for video mode, do not send cmds more than @@ -1262,10 +1262,14 @@ static int dsi_cmds2buf_tx(struct msm_dsi_host *msm_host, } ret = dsi_cmd_dma_tx(msm_host, len); - if (ret < len) { - pr_err("%s: cmd dma tx failed, type=0x%x, data0=0x%x, len=%d\n", - __func__, msg->type, (*(u8 *)(msg->tx_buf)), len); - return -ECOMM; + if (ret < 0) { + pr_err("%s: cmd dma tx failed, type=0x%x, data0=0x%x, len=%d, ret=%d\n", + __func__, msg->type, (*(u8 *)(msg->tx_buf)), len, ret); + return ret; + } else if (ret < len) { + pr_err("%s: cmd dma tx failed, type=0x%x, data0=0x%x, ret=%d len=%d\n", + __func__, msg->type, (*(u8 *)(msg->tx_buf)), ret, len); + return -EIO; } return len; @@ -1979,9 +1983,12 @@ int msm_dsi_host_cmd_rx(struct mipi_dsi_host *host, } ret = dsi_cmds2buf_tx(msm_host, msg); - if (ret < msg->tx_len) { + if (ret < 0) { pr_err("%s: Read cmd Tx failed, %d\n", __func__, ret); return ret; + } else if (ret < msg->tx_len) { + pr_err("%s: Read cmd Tx failed, too short: %d\n", __func__, ret); + return -ECOMM; } /* -- 2.35.1