From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754221AbcKROyH (ORCPT ); Fri, 18 Nov 2016 09:54:07 -0500 Received: from hqemgate14.nvidia.com ([216.228.121.143]:16786 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932221AbcKROwf (ORCPT ); Fri, 18 Nov 2016 09:52:35 -0500 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Thu, 17 Nov 2016 18:51:26 -0800 From: Laxman Dewangan To: , CC: , , , Laxman Dewangan , Douglas Anderson , Aleksandr Frid Subject: [PATCH V2 2/2] regulator: pwm: Add ramp delay for exponential voltage transition Date: Fri, 18 Nov 2016 20:05:56 +0530 Message-ID: <1479479756-10755-2-git-send-email-ldewangan@nvidia.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1479479756-10755-1-git-send-email-ldewangan@nvidia.com> References: <1479479756-10755-1-git-send-email-ldewangan@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some PWM regulator has the exponential transition in voltage change as opposite to fixed slew-rate linear transition on other regulators. For such PWM regulators, add support for handling the exponential voltage ramp delay. Signed-off-by: Laxman Dewangan CC: Douglas Anderson CC: Aleksandr Frid --- This patch is continuation of discussion on patch regulator: pwm: Fix regulator ramp delay for continuous mode https://patchwork.kernel.org/patch/9216857/ where is it discussed to have separate property for PWM which has exponential voltage transition. Changes from V1: - Use new DT property to finding that voltage ramp is exponential or not and use flag for having fixed delay for all voltage change. --- drivers/regulator/pwm-regulator.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c index 1b88e0e1..bcffeee 100644 --- a/drivers/regulator/pwm-regulator.c +++ b/drivers/regulator/pwm-regulator.c @@ -233,6 +233,24 @@ static int pwm_regulator_set_voltage(struct regulator_dev *rdev, return 0; } +/** + * Some of PWM regulators have exponential voltage ramp. On such PWM + * regulators, voltage settling time is same regardless of voltage + * level change. + */ +static int pwm_regulator_set_voltage_time(struct regulator_dev *rdev, + int old_uV, int new_uV) +{ + return rdev->constraints->ramp_delay; +} + +static int pwm_regulator_set_voltage_time_sel(struct regulator_dev *rdev, + unsigned int old_selector, + unsigned int new_selector) +{ + return rdev->constraints->ramp_delay; +} + static struct regulator_ops pwm_regulator_voltage_table_ops = { .set_voltage_sel = pwm_regulator_set_voltage_sel, .get_voltage_sel = pwm_regulator_get_voltage_sel, @@ -294,17 +312,25 @@ static int pwm_regulator_init_table(struct platform_device *pdev, drvdata->desc.ops = &drvdata->ops; drvdata->desc.n_voltages = length / sizeof(*duty_cycle_table); + if (of_property_read_bool(np, "voltage-ramp-exponential")) + drvdata->ops.set_voltage_time_sel = + pwm_regulator_set_voltage_time_sel; return 0; } static int pwm_regulator_init_continuous(struct platform_device *pdev, struct pwm_regulator_data *drvdata) { + struct device_node *np = pdev->dev.of_node; u32 dutycycle_range[2] = { 0, 100 }; u32 dutycycle_unit = 100; memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops, sizeof(drvdata->ops)); + + if (of_property_read_bool(np, "voltage-ramp-exponential")) + drvdata->ops.set_voltage_time = pwm_regulator_set_voltage_time; + drvdata->desc.ops = &drvdata->ops; drvdata->desc.continuous_voltage_range = true; -- 2.1.4