From patchwork Mon Jul 22 22:25:35 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin King X-Patchwork-Id: 11053581 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 97B8414F6 for ; Mon, 22 Jul 2019 22:30:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 874C32094F for ; Mon, 22 Jul 2019 22:30:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7AFBD22B1F; Mon, 22 Jul 2019 22:30:38 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, 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 31A49262F2 for ; Mon, 22 Jul 2019 22:30:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733162AbfGVWah (ORCPT ); Mon, 22 Jul 2019 18:30:37 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:59625 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727391AbfGVWah (ORCPT ); Mon, 22 Jul 2019 18:30:37 -0400 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1hpgkR-00024f-KX; Mon, 22 Jul 2019 22:25:35 +0000 From: Colin King To: Inki Dae , Joonyoung Shim , Seung-Woo Kim , Kyungmin Park , David Airlie , Daniel Vetter , Kukjin Kim , Krzysztof Kozlowski , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] drm/exynos: fix missing decrement of retry counter Date: Mon, 22 Jul 2019 23:25:35 +0100 Message-Id: <20190722222535.19114-1-colin.king@canonical.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-samsung-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Colin Ian King Currently the retry counter is not being decremented, leading to a potential infinite spin if the scalar_reads don't change state. Addresses-Coverity: ("Infinite loop") Fixes: 280e54c9f614 ("drm/exynos: scaler: Reset hardware before starting the operation") Signed-off-by: Colin Ian King --- drivers/gpu/drm/exynos/exynos_drm_scaler.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/exynos/exynos_drm_scaler.c b/drivers/gpu/drm/exynos/exynos_drm_scaler.c index 9af096479e1c..b24ba948b725 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_scaler.c +++ b/drivers/gpu/drm/exynos/exynos_drm_scaler.c @@ -94,12 +94,12 @@ static inline int scaler_reset(struct scaler_context *scaler) scaler_write(SCALER_CFG_SOFT_RESET, SCALER_CFG); do { cpu_relax(); - } while (retry > 1 && + } while (--retry > 1 && scaler_read(SCALER_CFG) & SCALER_CFG_SOFT_RESET); do { cpu_relax(); scaler_write(1, SCALER_INT_EN); - } while (retry > 0 && scaler_read(SCALER_INT_EN) != 1); + } while (--retry > 0 && scaler_read(SCALER_INT_EN) != 1); return retry ? 0 : -EIO; }