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 B145DC77B75 for ; Tue, 18 Apr 2023 12:41:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231854AbjDRMlj (ORCPT ); Tue, 18 Apr 2023 08:41:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231861AbjDRMlj (ORCPT ); Tue, 18 Apr 2023 08:41:39 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 76471146E1 for ; Tue, 18 Apr 2023 05:41:23 -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 0E83C63320 for ; Tue, 18 Apr 2023 12:41:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22A25C4339C; Tue, 18 Apr 2023 12:41:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1681821682; bh=XAdkwq/v7ensHuK/Jwi7tilFGTqQ2dc2NiexxrLVGSY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CVCAw0/B9uibM6f83HvoVNefKvx9JGGTdAm2l7aBilz1/mbNP+75PFb3bffHMix4o e0vZuZLt7HwfbcXsiW4ltCCCUoXVgBz8c9JETn+ny3ce1w8++yil0HJYEP7eaa36z4 21iCCgU26xu2tk+TbSPxgAPhMA01is+136ptZx10= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Gregor Herburger , Matthias Schiffer , Peter Korsgaard , Andrew Lunn , Federico Vaga , Wolfram Sang , Sasha Levin Subject: [PATCH 5.15 73/91] i2c: ocores: generate stop condition after timeout in polling mode Date: Tue, 18 Apr 2023 14:22:17 +0200 Message-Id: <20230418120308.082437992@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230418120305.520719816@linuxfoundation.org> References: <20230418120305.520719816@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Gregor Herburger [ Upstream commit f8160d3b35fc94491bb0cb974dbda310ef96c0e2 ] In polling mode, no stop condition is generated after a timeout. This causes SCL to remain low and thereby block the bus. If this happens during a transfer it can cause slaves to misinterpret the subsequent transfer and return wrong values. To solve this, pass the ETIMEDOUT error up from ocores_process_polling() instead of setting STATE_ERROR directly. The caller is adjusted to call ocores_process_timeout() on error both in polling and in IRQ mode, which will set STATE_ERROR and generate a stop condition. Fixes: 69c8c0c0efa8 ("i2c: ocores: add polling interface") Signed-off-by: Gregor Herburger Signed-off-by: Matthias Schiffer Acked-by: Peter Korsgaard Reviewed-by: Andrew Lunn Reviewed-by: Federico Vaga Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-ocores.c | 35 ++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 16 deletions(-) diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c index a0af027db04c1..2e575856c5cd5 100644 --- a/drivers/i2c/busses/i2c-ocores.c +++ b/drivers/i2c/busses/i2c-ocores.c @@ -342,18 +342,18 @@ static int ocores_poll_wait(struct ocores_i2c *i2c) * ocores_isr(), we just add our polling code around it. * * It can run in atomic context + * + * Return: 0 on success, -ETIMEDOUT on timeout */ -static void ocores_process_polling(struct ocores_i2c *i2c) +static int ocores_process_polling(struct ocores_i2c *i2c) { - while (1) { - irqreturn_t ret; - int err; + irqreturn_t ret; + int err = 0; + while (1) { err = ocores_poll_wait(i2c); - if (err) { - i2c->state = STATE_ERROR; + if (err) break; /* timeout */ - } ret = ocores_isr(-1, i2c); if (ret == IRQ_NONE) @@ -364,13 +364,15 @@ static void ocores_process_polling(struct ocores_i2c *i2c) break; } } + + return err; } static int ocores_xfer_core(struct ocores_i2c *i2c, struct i2c_msg *msgs, int num, bool polling) { - int ret; + int ret = 0; u8 ctrl; ctrl = oc_getreg(i2c, OCI2C_CONTROL); @@ -388,15 +390,16 @@ static int ocores_xfer_core(struct ocores_i2c *i2c, oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_START); if (polling) { - ocores_process_polling(i2c); + ret = ocores_process_polling(i2c); } else { - ret = wait_event_timeout(i2c->wait, - (i2c->state == STATE_ERROR) || - (i2c->state == STATE_DONE), HZ); - if (ret == 0) { - ocores_process_timeout(i2c); - return -ETIMEDOUT; - } + if (wait_event_timeout(i2c->wait, + (i2c->state == STATE_ERROR) || + (i2c->state == STATE_DONE), HZ) == 0) + ret = -ETIMEDOUT; + } + if (ret) { + ocores_process_timeout(i2c); + return ret; } return (i2c->state == STATE_DONE) ? num : -EIO; -- 2.39.2