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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 6FDF4C433E2 for ; Sun, 30 Aug 2020 16:39:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 553ED20714 for ; Sun, 30 Aug 2020 16:39:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726839AbgH3Qjd (ORCPT ); Sun, 30 Aug 2020 12:39:33 -0400 Received: from hostingweb31-40.netsons.net ([89.40.174.40]:55691 "EHLO hostingweb31-40.netsons.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726394AbgH3QjH (ORCPT ); Sun, 30 Aug 2020 12:39:07 -0400 Received: from [78.134.86.56] (port=34202 helo=melee.dev.aim) by hostingweb31.netsons.net with esmtpa (Exim 4.93) (envelope-from ) id 1kCQMC-000E3G-Of; Sun, 30 Aug 2020 18:39:04 +0200 From: Luca Ceresoli To: linux-fpga@vger.kernel.org Cc: Luca Ceresoli , Moritz Fischer , Tom Rix , Michal Simek , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Anatolij Gustschin Subject: [PATCH v4 4/5] fpga manager: xilinx-spi: add error checking after gpiod_get_value() Date: Sun, 30 Aug 2020 18:38:49 +0200 Message-Id: <20200830163850.8380-4-luca@lucaceresoli.net> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200830163850.8380-1-luca@lucaceresoli.net> References: <20200830163850.8380-1-luca@lucaceresoli.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - hostingweb31.netsons.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - lucaceresoli.net X-Get-Message-Sender-Via: hostingweb31.netsons.net: authenticated_id: luca+lucaceresoli.net/only user confirmed/virtual account not confirmed X-Authenticated-Sender: hostingweb31.netsons.net: luca@lucaceresoli.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Current code calls gpiod_get_value() without error checking. Should the GPIO controller fail, execution would continue without any error message. Fix by checking for negative error values. Reported-by: Tom Rix Reviewed-by: Tom Rix Signed-off-by: Luca Ceresoli --- Changes in v4: - add Reviewed-by Tom Rix Changes in v3: - rebase on previous patches This patch is new in v2 --- drivers/fpga/xilinx-spi.c | 35 +++++++++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 8 deletions(-) diff --git a/drivers/fpga/xilinx-spi.c b/drivers/fpga/xilinx-spi.c index fba8eb4866a7..52aab5a1f0ba 100644 --- a/drivers/fpga/xilinx-spi.c +++ b/drivers/fpga/xilinx-spi.c @@ -27,11 +27,22 @@ struct xilinx_spi_conf { struct gpio_desc *done; }; -static enum fpga_mgr_states xilinx_spi_state(struct fpga_manager *mgr) +static int get_done_gpio(struct fpga_manager *mgr) { struct xilinx_spi_conf *conf = mgr->priv; + int ret; + + ret = gpiod_get_value(conf->done); + + if (ret < 0) + dev_err(&mgr->dev, "Error reading DONE (%d)\n", ret); - if (!gpiod_get_value(conf->done)) + return ret; +} + +static enum fpga_mgr_states xilinx_spi_state(struct fpga_manager *mgr) +{ + if (!get_done_gpio(mgr)) return FPGA_MGR_STATE_RESET; return FPGA_MGR_STATE_UNKNOWN; @@ -57,10 +68,21 @@ static int wait_for_init_b(struct fpga_manager *mgr, int value, if (conf->init_b) { while (time_before(jiffies, timeout)) { - if (gpiod_get_value(conf->init_b) == value) + int ret = gpiod_get_value(conf->init_b); + + if (ret == value) return 0; + + if (ret < 0) { + dev_err(&mgr->dev, "Error reading INIT_B (%d)\n", ret); + return ret; + } + usleep_range(100, 400); } + + dev_err(&mgr->dev, "Timeout waiting for INIT_B to %s\n", + value ? "assert" : "deassert"); return -ETIMEDOUT; } @@ -85,7 +107,6 @@ static int xilinx_spi_write_init(struct fpga_manager *mgr, err = wait_for_init_b(mgr, 1, 1); /* min is 500 ns */ if (err) { - dev_err(&mgr->dev, "INIT_B pin did not go low\n"); gpiod_set_value(conf->prog_b, 0); return err; } @@ -93,12 +114,10 @@ static int xilinx_spi_write_init(struct fpga_manager *mgr, gpiod_set_value(conf->prog_b, 0); err = wait_for_init_b(mgr, 0, 0); - if (err) { - dev_err(&mgr->dev, "INIT_B pin did not go high\n"); + if (err) return err; - } - if (gpiod_get_value(conf->done)) { + if (get_done_gpio(mgr)) { dev_err(&mgr->dev, "Unexpected DONE pin state...\n"); return -EIO; } -- 2.28.0