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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 5DDDDC43603 for ; Sun, 8 Dec 2019 13:59:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 35BD320721 for ; Sun, 8 Dec 2019 13:59:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727379AbfLHN7D (ORCPT ); Sun, 8 Dec 2019 08:59:03 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:59976 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726589AbfLHNyk (ORCPT ); Sun, 8 Dec 2019 08:54:40 -0500 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1idx1B-0007dX-Kb; Sun, 08 Dec 2019 13:54:37 +0000 Received: from ben by deadeye with local (Exim 4.93-RC1) (envelope-from ) id 1idx1A-0002Ll-Ue; Sun, 08 Dec 2019 13:54:36 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Marc Kleine-Budde" , "Sean Nyekjaer" Date: Sun, 08 Dec 2019 13:53:01 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 17/72] can: mcp251x: mcp251x_hw_reset(): allow more time after a reset In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.79-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Marc Kleine-Budde commit d84ea2123f8d27144e3f4d58cd88c9c6ddc799de upstream. Some boards take longer than 5ms to power up after a reset, so allow some retries attempts before giving up. Fixes: ff06d611a31c ("can: mcp251x: Improve mcp251x_hw_reset()") Tested-by: Sean Nyekjaer Signed-off-by: Marc Kleine-Budde [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- drivers/net/can/spi/mcp251x.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) --- a/drivers/net/can/spi/mcp251x.c +++ b/drivers/net/can/spi/mcp251x.c @@ -626,7 +626,7 @@ static int mcp251x_setup(struct net_devi static int mcp251x_hw_reset(struct spi_device *spi) { struct mcp251x_priv *priv = spi_get_drvdata(spi); - u8 reg; + unsigned long timeout; int ret; /* Wait for oscillator startup timer after power up */ @@ -640,10 +640,19 @@ static int mcp251x_hw_reset(struct spi_d /* Wait for oscillator startup timer after reset */ mdelay(MCP251X_OST_DELAY_MS); - reg = mcp251x_read_reg(spi, CANSTAT); - if ((reg & CANCTRL_REQOP_MASK) != CANCTRL_REQOP_CONF) - return -ENODEV; + /* Wait for reset to finish */ + timeout = jiffies + HZ; + while ((mcp251x_read_reg(spi, CANSTAT) & CANCTRL_REQOP_MASK) != + CANCTRL_REQOP_CONF) { + usleep_range(MCP251X_OST_DELAY_MS * 1000, + MCP251X_OST_DELAY_MS * 1000 * 2); + if (time_after(jiffies, timeout)) { + dev_err(&spi->dev, + "MCP251x didn't enter in conf mode after reset\n"); + return -EBUSY; + } + } return 0; }