Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755422AbcC3UFq (ORCPT ); Wed, 30 Mar 2016 16:05:46 -0400 Received: from down.free-electrons.com ([37.187.137.238]:45576 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755326AbcC3UFk (ORCPT ); Wed, 30 Mar 2016 16:05:40 -0400 From: Boris Brezillon To: Thierry Reding , linux-pwm@vger.kernel.org Cc: Mike Turquette , Stephen Boyd , linux-clk@vger.kernel.org, Mark Brown , Liam Girdwood , Kamil Debski , lm-sensors@lm-sensors.org, Jean Delvare , Guenter Roeck , Dmitry Torokhov , linux-input@vger.kernel.org, Bryan Wu , Richard Purdie , Jacek Anaszewski , linux-leds@vger.kernel.org, Maxime Ripard , Chen-Yu Tsai , linux-sunxi@googlegroups.com, Joachim Eastwood , Thomas Petazzoni , Heiko Stuebner , linux-rockchip@lists.infradead.org, Jingoo Han , Lee Jones , linux-fbdev@vger.kernel.org, Jean-Christophe Plagniol-Villard , Tomi Valkeinen , Robert Jarzmik , Alexandre Belloni , Kukjin Kim , Krzysztof Kozlowski , linux-samsung-soc@vger.kernel.org, intel-gfx@lists.freedesktop.org, Daniel Vetter , Jani Nikula , Jonathan Corbet , linux-doc@vger.kernel.org, David Airlie , Daniel Vetter , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Hartley Sweeten , Ryan Mallon , Alexander Shiyan , Milo Kim , Boris Brezillon Subject: [PATCH v5 30/46] regulator: pwm: retrieve correct voltage Date: Wed, 30 Mar 2016 22:03:53 +0200 Message-Id: <1459368249-13241-31-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> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2119 Lines: 69 The continuous PWM voltage regulator is caching the voltage value in the ->volt_uV field. While most of the time this value should reflect the real voltage, sometime it can be sightly different if the PWM device rounded the set_duty_cycle request. Moreover, this value is not valid until someone has modified the regulator output. Remove the ->volt_uV field and always rely on the PWM state to calculate the regulator output. Signed-off-by: Boris Brezillon --- drivers/regulator/pwm-regulator.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c index 9374796..77f42d8 100644 --- a/drivers/regulator/pwm-regulator.c +++ b/drivers/regulator/pwm-regulator.c @@ -35,9 +35,6 @@ struct pwm_regulator_data { struct regulator_ops ops; int state; - - /* Continuous voltage */ - int volt_uV; }; struct pwm_voltages { @@ -167,11 +164,27 @@ static int pwm_voltage_to_duty_cycle_percentage(struct regulator_dev *rdev, int return ((req_uV * 100) - (min_uV * 100)) / diff; } +static int pwm_duty_cycle_percentage_to_voltage(struct regulator_dev *rdev, + int dutycycle) +{ + int min_uV = rdev->constraints->min_uV; + int max_uV = rdev->constraints->max_uV; + int diff = max_uV - min_uV; + + return min_uV + ((diff * dutycycle) / 100); +} + static int pwm_regulator_get_voltage(struct regulator_dev *rdev) { struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); + struct pwm_state pstate; + u64 dutycycle; - return drvdata->volt_uV; + pwm_get_state(drvdata->pwm, &pstate); + dutycycle = pstate.duty_cycle * 100; + do_div(dutycycle, pstate.period); + + return pwm_duty_cycle_percentage_to_voltage(rdev, dutycycle); } static int pwm_regulator_set_voltage(struct regulator_dev *rdev, @@ -196,8 +209,6 @@ static int pwm_regulator_set_voltage(struct regulator_dev *rdev, return ret; } - drvdata->volt_uV = min_uV; - /* Delay required by PWM regulator to settle to the new voltage */ usleep_range(ramp_delay, ramp_delay + 1000); -- 2.5.0