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 7BB60C43334 for ; Mon, 13 Jun 2022 10:45:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245284AbiFMKo7 (ORCPT ); Mon, 13 Jun 2022 06:44:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344551AbiFMKml (ORCPT ); Mon, 13 Jun 2022 06:42:41 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79575D137; Mon, 13 Jun 2022 03:24:07 -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 ams.source.kernel.org (Postfix) with ESMTPS id 12F9AB80E2D; Mon, 13 Jun 2022 10:24:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7E47BC34114; Mon, 13 Jun 2022 10:24:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655115844; bh=SnyxOO3TTXiksI43VckClFdeIRI3OXADoqiNsPJ6c88=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fKwt8EhwfsUMo6a9rD/z2fZOf06jZcHpUJ+I4pqZXpGJyiWLcTCX11V5C4zTWZRNi XwPKiJELiEWo/HiA/TENPx4XjzxcEMtatUDV2dRHpiHUektNf1Dlu8ruhLW4uAy2Tq QfYASbWSYlsAa1lcMiq4XFrFWW30+0ZoHb4VWwAE= 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 4.14 062/218] drm/msm/dsi: fix error checks and return values for DSI xmit functions Date: Mon, 13 Jun 2022 12:08:40 +0200 Message-Id: <20220613094921.606547638@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094908.257446132@linuxfoundation.org> References: <20220613094908.257446132@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 d49f17748119..c9c8d2190515 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; @@ -1988,9 +1992,12 @@ 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