Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933238AbbGGSde (ORCPT ); Tue, 7 Jul 2015 14:33:34 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:43342 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933416AbbGGSbI (ORCPT ); Tue, 7 Jul 2015 14:31:08 -0400 From: Mark Brown To: Lee Jones , Mark Brown Cc: linux-kernel@vger.kernel.org In-Reply-To: <1436281613-899-8-git-send-email-lee.jones@linaro.org> Message-Id: Date: Tue, 07 Jul 2015 19:31:01 +0100 X-SA-Exim-Connect-IP: 94.175.94.161 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Applied "regulator: pwm-regulator: Add support for continuous-voltage" to the regulator tree X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6919 Lines: 228 The patch regulator: pwm-regulator: Add support for continuous-voltage has been applied to the regulator tree at git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From 4773be185a0f7c1c09d8966e100c76f4fa9a3227 Mon Sep 17 00:00:00 2001 From: Lee Jones Date: Tue, 7 Jul 2015 16:06:51 +0100 Subject: [PATCH] regulator: pwm-regulator: Add support for continuous-voltage The current version of PWM regulator only supports a static table approach, where pre-calculated values are supplied by the vendor and obtained via DT. The continuous-voltage method takes min_uV and max_uV, and divides the difference between them up into a number of slices. The number of slices depend on how large the duty cycle register is. This information is provided by a DT property. As the name alludes, this provides values for a continuous voltage range between min_uV and max_uV, which has obvious benefits over either limited voltage possibilities, or the requirement to provide a large voltage-table. Signed-off-by: Lee Jones Signed-off-by: Mark Brown --- drivers/regulator/pwm-regulator.c | 114 +++++++++++++++++++++++++++++++++++--- 1 file changed, 106 insertions(+), 8 deletions(-) diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c index 25560fc519b7..dac145db305c 100644 --- a/drivers/regulator/pwm-regulator.c +++ b/drivers/regulator/pwm-regulator.c @@ -10,6 +10,7 @@ * published by the Free Software Foundation. */ +#include #include #include #include @@ -21,9 +22,16 @@ #include struct pwm_regulator_data { - struct pwm_voltages *duty_cycle_table; + /* Shared */ struct pwm_device *pwm; + + /* Voltage table */ + struct pwm_voltages *duty_cycle_table; int state; + + /* Continuous voltage */ + u32 max_duty_cycle; + int volt_uV; }; struct pwm_voltages { @@ -31,6 +39,9 @@ struct pwm_voltages { unsigned int dutycycle; }; +/** + * Voltage table call-backs + */ static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev) { struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); @@ -78,6 +89,71 @@ static int pwm_regulator_list_voltage(struct regulator_dev *rdev, return drvdata->duty_cycle_table[selector].uV; } + +/** + * Continuous voltage call-backs + */ +static int pwm_voltage_to_duty_cycle(struct regulator_dev *rdev, + int volt_mV) +{ + struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); + int min_mV = rdev->constraints->min_uV / 1000; + int max_mV = rdev->constraints->max_uV / 1000; + int max_duty_cycle = drvdata->max_duty_cycle; + int vdiff = min_mV - max_mV; + int pwm_code; + int tmp; + + tmp = ((max_duty_cycle - min_mV) * max_duty_cycle) / vdiff; + pwm_code = ((tmp + max_duty_cycle) * volt_mV) / vdiff; + + if (pwm_code < 0) + pwm_code = 0; + if (pwm_code > max_duty_cycle) + pwm_code = max_duty_cycle; + + return pwm_code * 100 / max_duty_cycle; +} + +static int pwm_regulator_get_voltage(struct regulator_dev *rdev) +{ + struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); + + return drvdata->volt_uV; +} + +static int pwm_regulator_set_voltage(struct regulator_dev *rdev, + int min_uV, int max_uV, + unsigned *selector) +{ + struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); + unsigned int ramp_delay = rdev->constraints->ramp_delay; + int duty_cycle; + int ret; + + duty_cycle = pwm_voltage_to_duty_cycle(rdev, min_uV / 1000); + + ret = pwm_config(drvdata->pwm, + (drvdata->pwm->period / 100) * duty_cycle, + drvdata->pwm->period); + if (ret) { + dev_err(&rdev->dev, "Failed to configure PWM\n"); + return ret; + } + + ret = pwm_enable(drvdata->pwm); + if (ret) { + dev_err(&rdev->dev, "Failed to enable PWM\n"); + 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); + + return 0; +} + 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, @@ -85,6 +161,11 @@ static struct regulator_ops pwm_regulator_voltage_table_ops = { .map_voltage = regulator_map_voltage_iterate, }; +static struct regulator_ops pwm_regulator_voltage_continuous_ops = { + .get_voltage = pwm_regulator_get_voltage, + .set_voltage = pwm_regulator_set_voltage, +}; + static struct regulator_desc pwm_regulator_desc = { .name = "pwm-regulator", .type = REGULATOR_VOLTAGE, @@ -129,6 +210,25 @@ static int pwm_regulator_init_table(struct platform_device *pdev, 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; + int ret; + + ret = of_property_read_u32(np, "max-duty-cycle", + &drvdata->max_duty_cycle); + if (ret) { + dev_err(&pdev->dev, "Failed to read \"pwm-max-value\"\n"); + return ret; + } + + pwm_regulator_desc.ops = &pwm_regulator_voltage_continuous_ops; + pwm_regulator_desc.continuous_voltage_range = true; + + return 0; +} + static int pwm_regulator_probe(struct platform_device *pdev) { struct pwm_regulator_data *drvdata; @@ -146,14 +246,12 @@ static int pwm_regulator_probe(struct platform_device *pdev) if (!drvdata) return -ENOMEM; - if (of_find_property(np, "voltage-table", NULL)) { + if (of_find_property(np, "voltage-table", NULL)) ret = pwm_regulator_init_table(pdev, drvdata); - if (ret) - return ret; - } else { - dev_err(&pdev->dev, "No \"voltage-table\" supplied\n"); - return -EINVAL; - } + else + ret = pwm_regulator_init_continuous(pdev, drvdata); + if (ret) + return ret; config.init_data = of_get_regulator_init_data(&pdev->dev, np, &pwm_regulator_desc); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/