From patchwork Tue Aug 8 07:02:44 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 9886681 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 883D560352 for ; Tue, 8 Aug 2017 07:04:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7A71028743 for ; Tue, 8 Aug 2017 07:04:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6F0F82875E; Tue, 8 Aug 2017 07:04:33 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 06C5328743 for ; Tue, 8 Aug 2017 07:04:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751987AbdHHHCt (ORCPT ); Tue, 8 Aug 2017 03:02:49 -0400 Received: from mirror2.csie.ntu.edu.tw ([140.112.30.76]:45644 "EHLO wens.csie.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751880AbdHHHCr (ORCPT ); Tue, 8 Aug 2017 03:02:47 -0400 Received: by wens.csie.org (Postfix, from userid 1000) id EA2AF5FF30; Tue, 8 Aug 2017 15:02:44 +0800 (CST) From: Chen-Yu Tsai To: Ulf Hansson , Maxime Ripard Cc: Chen-Yu Tsai , Icenowy Zheng , linux-mmc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@googlegroups.com Subject: [PATCH v2] mmc: sunxi: Fix NULL pointer reference on clk_delays Date: Tue, 8 Aug 2017 15:02:44 +0800 Message-Id: <20170808070244.27410-1-wens@csie.org> X-Mailer: git-send-email 2.13.3 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Some SoCs do not support clk delays for MMC in the clock control unit. These include the old controllers in A10/A10s/A13/R8, and the new eMMC controller in A64. The config structure for these controllers do not specify clk_delays, but the check for this was replaced in commit b0600daebf31 ("mmc: sunxi: Support controllers that can use both old and new timings"). This patch adds back the check for clk_delays, and also adds comments for both checks in sunxi_mmc_clk_set_phase(). Fixes: b0600daebf31 ("mmc: sunxi: Support controllers that can use both old and new timings") Signed-off-by: Chen-Yu Tsai Tested-by: Icenowy Zheng --- This fixes an mmc regression on A10/A10s/A13/R8 and A64 introduced by the A83T mmc patches. v1 was inlined in a reply to "mmc: sunxi: fix new timings mode on A64 EMMC (MMC2) controller" Changes since v1: - Polished comments I've tested this on my A10 Cubieboard and A20 Cubieboard2. --- drivers/mmc/host/sunxi-mmc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c index 3777517982dd..9dc6d726ec49 100644 --- a/drivers/mmc/host/sunxi-mmc.c +++ b/drivers/mmc/host/sunxi-mmc.c @@ -722,9 +722,14 @@ static int sunxi_mmc_clk_set_phase(struct sunxi_mmc_host *host, { int index; + /* clk controller delays not used under new timings mode */ if (host->use_new_timings) return 0; + /* some old controllers don't support delays */ + if (!host->cfg->clk_delays) + return 0; + /* determine delays */ if (rate <= 400000) { index = SDXC_CLK_400K;