From patchwork Wed Mar 22 17:21:25 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 9639581 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 48449602CB for ; Wed, 22 Mar 2017 17:22:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 407F328451 for ; Wed, 22 Mar 2017 17:22:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 32E682845B; Wed, 22 Mar 2017 17:22:06 +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 CDB6428451 for ; Wed, 22 Mar 2017 17:22:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934894AbdCVRVr (ORCPT ); Wed, 22 Mar 2017 13:21:47 -0400 Received: from andre.telenet-ops.be ([195.130.132.53]:36882 "EHLO andre.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934828AbdCVRVq (ORCPT ); Wed, 22 Mar 2017 13:21:46 -0400 Received: from ayla.of.borg ([84.193.137.253]) by andre.telenet-ops.be with bizsmtp id z5Mc1u0075UCtCs015McPg; Wed, 22 Mar 2017 18:21:39 +0100 Received: from ramsan.of.borg ([192.168.97.29] helo=ramsan) by ayla.of.borg with esmtp (Exim 4.86_2) (envelope-from ) id 1cqjx2-0000vp-6v; Wed, 22 Mar 2017 18:21:36 +0100 Received: from geert by ramsan with local (Exim 4.86_2) (envelope-from ) id 1cqjx2-0007Nc-4y; Wed, 22 Mar 2017 18:21:36 +0100 From: Geert Uytterhoeven To: Thierry Reding , Lee Jones , Daniel Thompson , Jingoo Han , Bartlomiej Zolnierkiewicz Cc: Peter Ujfalusi , Philipp Zabel , linux-pwm@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH] backlight: pwm_bl: Fix GPIO out for unimplemented .get_direction() Date: Wed, 22 Mar 2017 18:21:25 +0100 Message-Id: <1490203285-28324-1-git-send-email-geert+renesas@glider.be> X-Mailer: git-send-email 2.7.4 Sender: linux-fbdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Commit 7613c922315e308a ("backlight: pwm_bl: Move the checks for initial power state to a separate function") not just moved some code, but made slight changes in semantics. If a gpiochip doesn't implement the optional .get_direction() callback, gpiod_get_direction always returns -EINVAL, which is never equal to GPIOF_DIR_IN, leading to the GPIO not being configured for output. To avoid this, invert the test and check for not GPIOF_DIR_OUT instead, like the original code did. This restores the display on r8a7740/armadillo. Fixes: 7613c922315e308a ("backlight: pwm_bl: Move the checks for initial power state to a separate function") Signed-off-by: Geert Uytterhoeven Reviewed-by: Peter Ujfalusi Acked-by: Philipp Zabel Acked-by: Daniel Thommpson Acked-by: Daniel Thompson --- drivers/video/backlight/pwm_bl.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index d7efcb632f7d9dde..002f1ce22bd02032 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -297,14 +297,15 @@ static int pwm_backlight_probe(struct platform_device *pdev) } /* - * If the GPIO is configured as input, change the direction to output - * and set the GPIO as active. + * If the GPIO is not known to be already configured as output, that + * is, if gpiod_get_direction returns either GPIOF_DIR_IN or -EINVAL, + * change the direction to output and set the GPIO as active. * Do not force the GPIO to active when it was already output as it * could cause backlight flickering or we would enable the backlight too * early. Leave the decision of the initial backlight state for later. */ if (pb->enable_gpio && - gpiod_get_direction(pb->enable_gpio) == GPIOF_DIR_IN) + gpiod_get_direction(pb->enable_gpio) != GPIOF_DIR_OUT) gpiod_direction_output(pb->enable_gpio, 1); pb->power_supply = devm_regulator_get(&pdev->dev, "power");