From patchwork Mon May 2 19:14:22 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Javier Martinez Canillas X-Patchwork-Id: 8994961 Return-Path: X-Original-To: patchwork-linux-media@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 3FB8ABF29F for ; Mon, 2 May 2016 19:14:48 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 560E22024C for ; Mon, 2 May 2016 19:14:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6E51F20221 for ; Mon, 2 May 2016 19:14:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754903AbcEBTOo (ORCPT ); Mon, 2 May 2016 15:14:44 -0400 Received: from lists.s-osg.org ([54.187.51.154]:50469 "EHLO lists.s-osg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754885AbcEBTOm (ORCPT ); Mon, 2 May 2016 15:14:42 -0400 Received: from minerva.sisa.samsung.com (unknown [181.124.105.70]) by lists.s-osg.org (Postfix) with ESMTPSA id A07DAE28A8; Mon, 2 May 2016 12:14:43 -0700 (PDT) From: Javier Martinez Canillas To: linux-kernel@vger.kernel.org Cc: Marek Szyprowski , Krzysztof Kozlowski , Arnd Bergmann , Javier Martinez Canillas , Mauro Carvalho Chehab , Kamil Debski , Jeongtae Park , Kyungmin Park , linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org Subject: [PATCH v2] s5p-mfc: Don't try to put pm->clock if lookup failed Date: Mon, 2 May 2016 15:14:22 -0400 Message-Id: <1462216462-32665-1-git-send-email-javier@osg.samsung.com> X-Mailer: git-send-email 2.5.5 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Spam-Status: No, score=-7.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Failing to get the struct s5p_mfc_pm .clock is a non-fatal error so the clock field can have a errno pointer value. But s5p_mfc_final_pm() only checks if .clock is not NULL before attempting to unprepare and put it. This leads to the following warning in clk_put() due s5p_mfc_final_pm(): WARNING: CPU: 3 PID: 1023 at drivers/clk/clk.c:2814 s5p_mfc_final_pm+0x48/0x74 [s5p_mfc] CPU: 3 PID: 1023 Comm: rmmod Tainted: G W 4.6.0-rc6-next-20160502-00005-g5a15a49106bc #9 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [] (show_stack) from [] (dump_stack+0x88/0x9c) [] (dump_stack) from [] (__warn+0xe8/0x100) [] (__warn) from [] (warn_slowpath_null+0x20/0x28) [] (warn_slowpath_null) from [] (s5p_mfc_final_pm+0x48/0x74 [s5p_mfc]) [] (s5p_mfc_final_pm [s5p_mfc]) from [] (s5p_mfc_remove+0x8c/0x94 [s5p_mfc]) [] (s5p_mfc_remove [s5p_mfc]) from [] (platform_drv_remove+0x24/0x3c) [] (platform_drv_remove) from [] (__device_release_driver+0x84/0x110) [] (__device_release_driver) from [] (driver_detach+0xac/0xb0) [] (driver_detach) from [] (bus_remove_driver+0x4c/0xa0) [] (bus_remove_driver) from [] (SyS_delete_module+0x174/0x1b8) [] (SyS_delete_module) from [] (ret_fast_syscall+0x0/0x3c) Assign the pointer to NULL in case of a lookup failure to fix the issue. Signed-off-by: Javier Martinez Canillas Acked-by: Arnd Bergmann Reviewed-by: Krzysztof Kozlowski --- Changes in v2: - Set the clock pointer to NULL instead of checking for !IS_ERR_OR_NULL(). Suggested by Arnd Bergmann. drivers/media/platform/s5p-mfc/s5p_mfc_pm.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c b/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c index 5f97a3398c11..9f7522104333 100644 --- a/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c +++ b/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c @@ -54,6 +54,7 @@ int s5p_mfc_init_pm(struct s5p_mfc_dev *dev) pm->clock = clk_get(&dev->plat_dev->dev, MFC_SCLK_NAME); if (IS_ERR(pm->clock)) { mfc_info("Failed to get MFC special clock control\n"); + pm->clock = NULL; } else { clk_set_rate(pm->clock, MFC_SCLK_RATE); ret = clk_prepare_enable(pm->clock);