From patchwork Wed May 4 09:43:18 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= X-Patchwork-Id: 9011891 Return-Path: X-Original-To: patchwork-linux-fbdev@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 4D0CD9F39D for ; Wed, 4 May 2016 09:43:50 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 560A02038F for ; Wed, 4 May 2016 09:43:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3F90620382 for ; Wed, 4 May 2016 09:43:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756985AbcEDJnr (ORCPT ); Wed, 4 May 2016 05:43:47 -0400 Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:46531 "EHLO metis.ext.4.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757077AbcEDJnr (ORCPT ); Wed, 4 May 2016 05:43:47 -0400 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.80) (envelope-from ) id 1axtKz-0004JA-80; Wed, 04 May 2016 11:43:21 +0200 Received: from ukl by dude.hi.pengutronix.de with local (Exim 4.87) (envelope-from ) id 1axtKy-0001xU-IY; Wed, 04 May 2016 11:43:20 +0200 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= To: Jean-Christophe Plagniol-Villard , Tomi Valkeinen Cc: kernel@pengutronix.de, linux-fbdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 3/3] video: fbdev: imxfb: add some error handling Date: Wed, 4 May 2016 11:43:18 +0200 Message-Id: <1462354998-5792-4-git-send-email-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.8.0.rc3 In-Reply-To: <1462354998-5792-1-git-send-email-u.kleine-koenig@pengutronix.de> References: <1462354998-5792-1-git-send-email-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-fbdev@vger.kernel.org Sender: linux-fbdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org X-Spam-Status: No, score=-9.0 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham 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 clk_prepare_enable can fail and if it does the controller must not be considered enabled. So check for errors, properly unwind and give the error code back to the caller. While touching the clock code also enable the clocks in the same direction and disable in reverse order. Reviewed-by: Philipp Zabel Signed-off-by: Uwe Kleine-König --- Changes since (implicit) v1, sent with Message-Id: 1457380425-20244-4-git-send-email-u.kleine-koenig@pengutronix.de - Some simplifications suggested and Reviewed-by Philipp Zabel - Rework goto labels to have them at the end of the function (Tomi Valkeinen). drivers/video/fbdev/imxfb.c | 35 +++++++++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 8 deletions(-) diff --git a/drivers/video/fbdev/imxfb.c b/drivers/video/fbdev/imxfb.c index 18388ca178a2..23a623688f1e 100644 --- a/drivers/video/fbdev/imxfb.c +++ b/drivers/video/fbdev/imxfb.c @@ -473,11 +473,12 @@ static int imxfb_set_par(struct fb_info *info) return 0; } -static void imxfb_enable_controller(struct imxfb_info *fbi) +static int imxfb_enable_controller(struct imxfb_info *fbi) { + int ret; if (fbi->enabled) - return; + return 0; pr_debug("Enabling LCD controller\n"); @@ -496,10 +497,29 @@ static void imxfb_enable_controller(struct imxfb_info *fbi) */ writel(RMCR_LCDC_EN_MX1, fbi->regs + LCDC_RMCR); - clk_prepare_enable(fbi->clk_ipg); - clk_prepare_enable(fbi->clk_ahb); - clk_prepare_enable(fbi->clk_per); + ret = clk_prepare_enable(fbi->clk_ipg); + if (ret) + goto err_enable_ipg; + + ret = clk_prepare_enable(fbi->clk_ahb); + if (ret) + goto err_enable_ahb; + + ret = clk_prepare_enable(fbi->clk_per); + if (ret) + goto err_enable_per; + fbi->enabled = true; + return 0; + +err_enable_per: + clk_disable_unprepare(fbi->clk_ahb); +err_enable_ahb: + clk_disable_unprepare(fbi->clk_ipg); +err_enable_ipg: + writel(0, fbi->regs + LCDC_RMCR); + + return ret; } static void imxfb_disable_controller(struct imxfb_info *fbi) @@ -510,8 +530,8 @@ static void imxfb_disable_controller(struct imxfb_info *fbi) pr_debug("Disabling LCD controller\n"); clk_disable_unprepare(fbi->clk_per); - clk_disable_unprepare(fbi->clk_ipg); clk_disable_unprepare(fbi->clk_ahb); + clk_disable_unprepare(fbi->clk_ipg); fbi->enabled = false; writel(0, fbi->regs + LCDC_RMCR); @@ -532,8 +552,7 @@ static int imxfb_blank(int blank, struct fb_info *info) break; case FB_BLANK_UNBLANK: - imxfb_enable_controller(fbi); - break; + return imxfb_enable_controller(fbi); } return 0; }