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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 CF132C282CA for ; Sun, 27 Jan 2019 14:51:02 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9F64721736 for ; Sun, 27 Jan 2019 14:51:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="BzvJuRap" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9F64721736 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=csie.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=mua1lQkbsX3SM8K5qQ1DFzn5Uj7J6Ej6FBW7S8rth0k=; b=BzvJuRapBC8i89 MbsTbaWYgpAYmSHoDZVOf5XiB4baV1gjD1suEm1mnk3TVw0kK4Ez13W9G6VfPx+PtS8FgtBce1JT7 lzXehSh7qi6VcTjNTy0m4HSLRMyN2T3xaq3GM/tMyZlkgpEGxS+VFZmtT/TZCbk6Q2CMjadoiO3Js pqlqg/rDE9INssDurTF67c+kTWeHxWN/REb4xdnA0pbj1cib6mu+l1Ra2NQfDHnSfe8LZNGIFOGnP 4THja4GqPrwJQpDUaErHpTbJ93dp0uIBiLrZ/NPfowwwpj5CV6FsW5wekZQWzSZLM15gbsFdIqxVw J5icznYABtXFdKEomUeg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gnlm1-0003CV-8P; Sun, 27 Jan 2019 14:51:01 +0000 Received: from mirror2.csie.ntu.edu.tw ([140.112.30.76] helo=wens.csie.org) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gnllx-0003Bt-7Y for linux-arm-kernel@lists.infradead.org; Sun, 27 Jan 2019 14:50:58 +0000 Received: by wens.csie.org (Postfix, from userid 1000) id CC4905FD14; Sun, 27 Jan 2019 22:50:55 +0800 (CST) From: Chen-Yu Tsai To: Thierry Reding , Lee Jones , Daniel Thompson , Jingoo Han Subject: [PATCH] backlight: pwm_bl: Use gpiod_get_value_cansleep() to get initial state Date: Sun, 27 Jan 2019 22:50:54 +0800 Message-Id: <20190127145054.3770-1-wens@csie.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190127_065057_404431_CBE44327 X-CRM114-Status: GOOD ( 11.54 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, Maxime Ripard , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Chen-Yu Tsai , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 --- 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 feb90764a811..53b8ceea9bde 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -435,7 +435,7 @@ 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 */ -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel