From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5950DC43381 for ; Wed, 27 Mar 2019 18:15:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2CE4B21738 for ; Wed, 27 Mar 2019 18:15:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553710512; bh=ZU5RwbfEiO7IsGOqU7Wof/yoOaZkodhg/2O0X7EmJQc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2E0LFNh/WtVq5wwaZESkhMUNaAlxCxd+stVWqGHYoBnbZYkR+NQUuG7fnJCMuZLY7 fXai9ggFXJWnGn4iiJPzA59IOEzwZJdrBTp54Joc0+Lq56ChSZsYXhomJEvMUZ2YAq haEnErSPSdrsAyqGHfU/0C1uiD4e1mT1eyyL+Kdk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389787AbfC0SPL (ORCPT ); Wed, 27 Mar 2019 14:15:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:58574 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389768AbfC0SPI (ORCPT ); Wed, 27 Mar 2019 14:15:08 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EF44D2183E; Wed, 27 Mar 2019 18:15:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553710506; bh=ZU5RwbfEiO7IsGOqU7Wof/yoOaZkodhg/2O0X7EmJQc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1sPx/Ql3XXd77IJhcZiEgTEOS2RBQNhU4qtmjLHUVQqXs4VAaFbPBsXmuA5k3wuQ+ iZXOAjbAoA23rYCDjfSudUQbFfcrWmImVG8ejAP+cfgh322oB+VnWz6hYDEgh/d0h6 XhVINVRBzZ0Qu78aMucTicdk8PESbauzzoOH2V4Q= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Chen-Yu Tsai , Lee Jones , Sasha Levin , linux-pwm@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 150/192] backlight: pwm_bl: Use gpiod_get_value_cansleep() to get initial state Date: Wed, 27 Mar 2019 14:09:42 -0400 Message-Id: <20190327181025.13507-150-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190327181025.13507-1-sashal@kernel.org> References: <20190327181025.13507-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chen-Yu Tsai [ Upstream commit cec2b18832e26bc866bef2be22eff4e25bbc4034 ] gpiod_get_value() gives out a warning if access to the underlying gpiochip requires sleeping, which is common for I2C based chips: WARNING: CPU: 0 PID: 77 at drivers/gpio/gpiolib.c:2500 gpiod_get_value+0xd0/0x100 Modules linked in: CPU: 0 PID: 77 Comm: kworker/0:2 Not tainted 4.14.0-rc3-00589-gf32897915d48-dirty #90 Hardware name: Allwinner sun4i/sun5i Families Workqueue: events deferred_probe_work_func [] (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 [] (gpiod_get_value+0xd0/0x100) [] (gpiod_get_value) from [] (pwm_backlight_probe+0x238/0x508) [] (pwm_backlight_probe) from [] (platform_drv_probe+0x50/0xac) [] (platform_drv_probe) from [] (driver_probe_device+0x238/0x2e8) [] (driver_probe_device) from [] (bus_for_each_drv+0x44/0x94) [] (bus_for_each_drv) from [] (__device_attach+0xb0/0x114) [] (__device_attach) from [] (bus_probe_device+0x84/0x8c) [] (bus_probe_device) from [] (deferred_probe_work_func+0x50/0x14c) [] (deferred_probe_work_func) from [] (process_one_work+0x1ec/0x414) [] (process_one_work) from [] (worker_thread+0x2b0/0x5a0) [] (worker_thread) from [] (kthread+0x14c/0x154) [] (kthread) from [] (ret_from_fork+0x14/0x24) This was missed in commit 0c9501f823a4 ("backlight: pwm_bl: Handle gpio that can sleep"). The code was then moved to a separate function in commit 7613c922315e ("backlight: pwm_bl: Move the checks for initial power state to a separate function"). The only usage of gpiod_get_value() is during the probe stage, which is safe to sleep in. Switch to gpiod_get_value_cansleep(). Fixes: 0c9501f823a4 ("backlight: pwm_bl: Handle gpio that can sleep") Signed-off-by: Chen-Yu Tsai Acked-by: Maxime Ripard Acked-by: Daniel Thompson Signed-off-by: Lee Jones Signed-off-by: Sasha Levin --- drivers/video/backlight/pwm_bl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 6bde543452f2..7ddc0930e98c 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -425,7 +425,7 @@ static int pwm_backlight_initial_power_state(const struct pwm_bl_data *pb) */ /* if the enable GPIO is disabled, do not enable the backlight */ - if (pb->enable_gpio && gpiod_get_value(pb->enable_gpio) == 0) + if (pb->enable_gpio && gpiod_get_value_cansleep(pb->enable_gpio) == 0) return FB_BLANK_POWERDOWN; /* The regulator is disabled, do not enable the backlight */ -- 2.19.1