From patchwork Thu Jan 9 23:31:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?Q2zDqW1lbnQgUMOpcm9u?= X-Patchwork-Id: 1220699 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pwm-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=WHYq1fFh; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 47v2S375Ywz9sP6 for ; Fri, 10 Jan 2020 10:31:15 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725840AbgAIXbP (ORCPT ); Thu, 9 Jan 2020 18:31:15 -0500 Received: from mail-wr1-f65.google.com ([209.85.221.65]:37377 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726267AbgAIXbP (ORCPT ); Thu, 9 Jan 2020 18:31:15 -0500 Received: by mail-wr1-f65.google.com with SMTP id w15so24895wru.4 for ; Thu, 09 Jan 2020 15:31:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=L6mL2rwAPESuHHV2T0yqwj8NcOs/y+OPpLLCMYhkdgY=; b=WHYq1fFh9Cxbs9wNaMgifYWFbckwV0pUXZqMxJQCtBA3YP2j/BbVnFoVGSfN65SwSv gUiQ+lh/SQXhNWPPqEF9P+u4NjB54mMMprX9wevto19lDtvn2MmOi1qdH01q7ExdSYZA T4oJ9NVOU9Fbq5xWX4cRsKvqOVbyCsSsbrtEasmQROlKfYk86d7ksdG05+V5BfeswNCX GmXCGVNZUrHkOkgbiiqHhejqH9HEMkJNsogVlCBOBSzEoUqBNhVXQE2nHGf+7Oblzszo oBEqqB7TvA9q0jesZLGTK0YbHXjYJv6sxkbQeF4IAlIXxYRAnA6Vvjc3cKkcvQYqbNl+ bqRQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=L6mL2rwAPESuHHV2T0yqwj8NcOs/y+OPpLLCMYhkdgY=; b=MY/Q43EHPJLnwg7X0/14vM+7q2nf/K1348Apz6NwM3CT6XHDxY71FVNlFdTzzZ7+JB 4fWk37ZV+JCz/IYqNs4Y6AWlJVEXE8x0sNS1H3ASPLi4z3jJ7f/I0kR3SQ/UjTqKbqY1 JBimDRrhpch55H2ANBUMWzTvT71/jI6SenZm1CpCtokTwaWoT0aHUeDdPWNgpdagq1F5 jetksl9KY3y2pASizCVP2XAw6xrLiwEDRYu0b97RS1yxpPdsZyFYxIyW25bj2g+MaLV6 GUrsPjcyJzrcxb345H879rWUKKW33/BzG0DiccjRIsrQZunA0XyovKXZvWD+Y9rqys3k u5gg== X-Gm-Message-State: APjAAAW9OKQOr6qe5Lbe6NR/Q3HL4lsQv1qqHvFGjAeeN/0zgLGCqHYA Szn2t0n0Jth/28L4vCoRUiM= X-Google-Smtp-Source: APXvYqxYCt3lxuhdOfrbwTTC08LgsFznYbnh4QnkiyuzHfw0Pr0dMFXtnPnXBE6EQuGhXyiUcDU6zQ== X-Received: by 2002:adf:eb09:: with SMTP id s9mr237036wrn.61.1578612672652; Thu, 09 Jan 2020 15:31:12 -0800 (PST) Received: from localhost.localdomain ([2a01:e0a:1f1:d0f0::42f0:c285]) by smtp.gmail.com with ESMTPSA id h2sm107563wrt.45.2020.01.09.15.31.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Jan 2020 15:31:12 -0800 (PST) From: =?utf-8?b?Q2zDqW1lbnQgUMOpcm9u?= To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K?= =?utf-8?b?w7ZuaWc=?= Cc: linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, =?utf-8?b?Q2zDqW1lbnQgUMOpcm9u?= , Alex Mobigo , Vasily Khoruzhick Subject: [PATCH] [RFC] pwm: sun4i: Move pwm_calculate out of spin_lock Date: Fri, 10 Jan 2020 00:31:06 +0100 Message-Id: <20200109233106.17060-1-peron.clem@gmail.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-pwm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org pwm_calculate calls clk_get_rate while holding a spin_lock. This create an issue as clk_get_rate() may sleep. Move pwm_calculate out of this spin_lock. Fixes: c32c5c50d4fe ("pwm: sun4i: Switch to atomic PWM") Reported-by: Alex Mobigo Suggested-by: Vasily Khoruzhick Signed-off-by: Clément Péron Reviewed-by: Uwe Kleine-König Tested-By: Alexander Finger --- Hi, this issue has been reported on linux-sunxi Google groups. I don't have a board with PWM to confirm it. Please wait a tested-by. Thanks, Clément drivers/pwm/pwm-sun4i.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index 1afd41ebd3fd..6b230029dc49 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -248,19 +248,18 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, } } - spin_lock(&sun4i_pwm->ctrl_lock); - ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG); - ret = sun4i_pwm_calculate(sun4i_pwm, state, &duty, &period, &prescaler, &bypass); if (ret) { dev_err(chip->dev, "period exceeds the maximum value\n"); - spin_unlock(&sun4i_pwm->ctrl_lock); if (!cstate.enabled) clk_disable_unprepare(sun4i_pwm->clk); return ret; } + spin_lock(&sun4i_pwm->ctrl_lock); + ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG); + if (sun4i_pwm->data->has_direct_mod_clk_output) { if (bypass) { ctrl |= BIT_CH(PWM_BYPASS, pwm->hwpwm);