From patchwork Wed Mar 30 20:03:49 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris BREZILLON X-Patchwork-Id: 8706741 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id DC649C0553 for ; Thu, 31 Mar 2016 00:52:51 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0541920376 for ; Thu, 31 Mar 2016 00:52:51 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 1480E20357 for ; Thu, 31 Mar 2016 00:52:50 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 118B66E946; Thu, 31 Mar 2016 00:52:46 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail.free-electrons.com (down.free-electrons.com [37.187.137.238]) by gabe.freedesktop.org (Postfix) with ESMTP id 8862F6E8A1; Wed, 30 Mar 2016 20:05:28 +0000 (UTC) Received: by mail.free-electrons.com (Postfix, from userid 110) id 4A166185D; Wed, 30 Mar 2016 22:05:27 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from localhost.localdomain (LFbn-1-2159-240.w90-76.abo.wanadoo.fr [90.76.216.240]) by mail.free-electrons.com (Postfix) with ESMTPSA id 595701836; Wed, 30 Mar 2016 22:05:02 +0200 (CEST) From: Boris Brezillon To: Thierry Reding , linux-pwm@vger.kernel.org Subject: [PATCH v5 26/46] pwm: sun4i: implement hardware readout Date: Wed, 30 Mar 2016 22:03:49 +0200 Message-Id: <1459368249-13241-27-git-send-email-boris.brezillon@free-electrons.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1459368249-13241-1-git-send-email-boris.brezillon@free-electrons.com> References: <1459368249-13241-1-git-send-email-boris.brezillon@free-electrons.com> X-Mailman-Approved-At: Thu, 31 Mar 2016 00:47:56 +0000 Cc: Milo Kim , Kamil Debski , linux-doc@vger.kernel.org, Mike Turquette , linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com, Alexandre Belloni , Daniel Vetter , Lee Jones , linux-clk@vger.kernel.org, linux-leds@vger.kernel.org, Krzysztof Kozlowski , linux-samsung-soc@vger.kernel.org, Alexander Shiyan , Jonathan Corbet , Robert Jarzmik , lm-sensors@lm-sensors.org, linux-rockchip@lists.infradead.org, Chen-Yu Tsai , Tomi Valkeinen , linux-input@vger.kernel.org, Jean-Christophe Plagniol-Villard , intel-gfx@lists.freedesktop.org, Guenter Roeck , Jean Delvare , Joachim Eastwood , Bryan Wu , Mark Brown , Jacek Anaszewski , linux-arm-kernel@lists.infradead.org, Thomas Petazzoni , Ryan Mallon , Jingoo Han , Dmitry Torokhov , Stephen Boyd , Liam Girdwood , Hartley Sweeten , Richard Purdie , Kukjin Kim , Maxime Ripard X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP Implement ->get_state() instead of only initializing the polarity in the probe function. This implementation also takes care of keeping the PWM clk enabled if at least one of the PWM exported by the PWM chip is already enabled, which should prevent glitches. Signed-off-by: Boris Brezillon --- drivers/pwm/pwm-sun4i.c | 74 ++++++++++++++++++++++++++++++++++++------------- 1 file changed, 55 insertions(+), 19 deletions(-) diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index 03a99a5..34cb296 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -252,11 +252,65 @@ static void sun4i_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) clk_disable_unprepare(sun4i_pwm->clk); } +static void sun4i_pwm_get_state(struct pwm_chip *chip, + struct pwm_device *pwm, + struct pwm_state *pstate) +{ + struct sun4i_pwm_chip *sun4i_pwm = to_sun4i_pwm_chip(chip); + unsigned int clk_rate = clk_get_rate(sun4i_pwm->clk); + int prescaler, prescalerid; + int ret; + u32 val; + + ret = clk_prepare_enable(sun4i_pwm->clk); + if (ret) { + dev_err(chip->dev, "Failed to enable PWM clock"); + return; + } + + val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG); + if (val & BIT_CH(PWM_ACT_STATE, pwm->hwpwm)) + pstate->polarity = PWM_POLARITY_INVERSED; + else + pstate->polarity = PWM_POLARITY_NORMAL; + + if ((val & BIT_CH(PWM_EN, pwm->hwpwm)) && + (val & BIT_CH(PWM_CLK_GATING, pwm->hwpwm))) + pstate->enabled = true; + else + pstate->enabled = false; + + pstate->period = 0; + pstate->duty_cycle = 0; + prescalerid = (val >> (PWMCH_OFFSET * pwm->hwpwm)) & PWM_PRESCAL_MASK; + prescaler = prescaler_table[prescalerid]; + if (prescaler) { + u64 timens; + + clk_rate /= prescaler; + + val = sun4i_pwm_readl(sun4i_pwm, PWM_CH_PRD(pwm->hwpwm)); + + timens = ((val >> 16) & PWM_PRD_MASK) + 1; + timens *= NSEC_PER_SEC; + do_div(timens, clk_rate); + pstate->period = timens; + + timens = val & PWM_DTY_MASK; + timens *= NSEC_PER_SEC; + do_div(timens, clk_rate); + pstate->duty_cycle = timens; + } + + clk_disable_unprepare(sun4i_pwm->clk); +} + static const struct pwm_ops sun4i_pwm_ops = { .config = sun4i_pwm_config, .set_polarity = sun4i_pwm_set_polarity, .enable = sun4i_pwm_enable, .disable = sun4i_pwm_disable, + .get_state = sun4i_pwm_get_state, .owner = THIS_MODULE, }; @@ -307,8 +361,7 @@ static int sun4i_pwm_probe(struct platform_device *pdev) { struct sun4i_pwm_chip *pwm; struct resource *res; - u32 val; - int i, ret; + int ret; const struct of_device_id *match; match = of_match_device(sun4i_pwm_dt_ids, &pdev->dev); @@ -345,24 +398,7 @@ static int sun4i_pwm_probe(struct platform_device *pdev) platform_set_drvdata(pdev, pwm); - ret = clk_prepare_enable(pwm->clk); - if (ret) { - dev_err(&pdev->dev, "failed to enable PWM clock\n"); - goto clk_error; - } - - val = sun4i_pwm_readl(pwm, PWM_CTRL_REG); - for (i = 0; i < pwm->chip.npwm; i++) - if (!(val & BIT_CH(PWM_ACT_STATE, i))) - pwm_set_polarity(&pwm->chip.pwms[i], - PWM_POLARITY_INVERSED); - clk_disable_unprepare(pwm->clk); - return 0; - -clk_error: - pwmchip_remove(&pwm->chip); - return ret; } static int sun4i_pwm_remove(struct platform_device *pdev)