From 31e54086dd7bb86ad40f1d76a9063f2a95866b87 Mon Sep 17 00:00:00 2001 From: Pawel Moll Date: Mon, 24 Sep 2012 18:56:54 +0100 Subject: [PATCH] regulator: Versatile Express regulator driver Implementation of the regulator framework driver for the Versatile Express voltage control. Devices without voltage constraints (ie. "regulator-[min|max]-microvolt" properties in the DT node) are treated as fixed (or rather read-only) regulators. Signed-off-by: Pawel Moll Signed-off-by: Mark Brown --- .../devicetree/bindings/regulator/vexpress.txt | 32 +++++ drivers/regulator/Kconfig | 7 + drivers/regulator/Makefile | 1 + drivers/regulator/vexpress.c | 146 +++++++++++++++++++++ 4 files changed, 186 insertions(+) create mode 100644 Documentation/devicetree/bindings/regulator/vexpress.txt create mode 100644 drivers/regulator/vexpress.c diff --git a/Documentation/devicetree/bindings/regulator/vexpress.txt b/Documentation/devicetree/bindings/regulator/vexpress.txt new file mode 100644 index 0000000..d775f72 --- /dev/null +++ b/Documentation/devicetree/bindings/regulator/vexpress.txt @@ -0,0 +1,32 @@ +Versatile Express voltage regulators +------------------------------------ + +Requires node properties: +- "compatible" value: "arm,vexpress-volt" +- "arm,vexpress-sysreg,func" when controlled via vexpress-sysreg + (see Documentation/devicetree/bindings/arm/vexpress-sysreg.txt + for more details) + +Required regulator properties: +- "regulator-name" +- "regulator-always-on" + +Optional regulator properties: +- "regulator-min-microvolt" +- "regulator-max-microvolt" + +See Documentation/devicetree/bindings/regulator/regulator.txt +for more details about the regulator properties. + +When no "regulator-[min|max]-microvolt" properties are defined, +the device is treated as fixed (or rather "read-only") regulator. + +Example: + volt@0 { + compatible = "arm,vexpress-volt"; + arm,vexpress-sysreg,func = <2 0>; + regulator-name = "Cores"; + regulator-min-microvolt = <800000>; + regulator-max-microvolt = <1050000>; + regulator-always-on; + }; diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index 67d47b59..b44b019 100644 --- a/drivers/regulator/Kconfig +++ b/drivers/regulator/Kconfig @@ -422,6 +422,13 @@ config REGULATOR_TWL4030 This driver supports the voltage regulators provided by this family of companion chips. +config REGULATOR_VEXPRESS + tristate "Versatile Express regulators" + depends on VEXPRESS_CONFIG + help + This driver provides support for voltage regulators available + on the ARM Ltd's Versatile Express platform. + config REGULATOR_WM831X tristate "Wolfson Microelectronics WM831x PMIC regulators" depends on MFD_WM831X diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile index e431eed..9fa7a7b 100644 --- a/drivers/regulator/Makefile +++ b/drivers/regulator/Makefile @@ -57,6 +57,7 @@ obj-$(CONFIG_REGULATOR_TPS6586X) += tps6586x-regulator.o obj-$(CONFIG_REGULATOR_TPS65910) += tps65910-regulator.o obj-$(CONFIG_REGULATOR_TPS65912) += tps65912-regulator.o obj-$(CONFIG_REGULATOR_TWL4030) += twl-regulator.o +obj-$(CONFIG_REGULATOR_VEXPRESS) += vexpress.o obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o obj-$(CONFIG_REGULATOR_WM831X) += wm831x-isink.o obj-$(CONFIG_REGULATOR_WM831X) += wm831x-ldo.o diff --git a/drivers/regulator/vexpress.c b/drivers/regulator/vexpress.c new file mode 100644 index 0000000..1702945 --- /dev/null +++ b/drivers/regulator/vexpress.c @@ -0,0 +1,146 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Copyright (C) 2012 ARM Limited + */ + +#define DRVNAME "vexpress-regulator" +#define pr_fmt(fmt) DRVNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include + +struct vexpress_regulator { + struct regulator_desc desc; + struct regulator_dev *regdev; + struct vexpress_config_func *func; +}; + +static int vexpress_regulator_get_voltage(struct regulator_dev *regdev) +{ + struct vexpress_regulator *reg = rdev_get_drvdata(regdev); + u32 uV; + int err = vexpress_config_read(reg->func, 0, &uV); + + return err ? err : uV; +} + +static int vexpress_regulator_set_voltage(struct regulator_dev *regdev, + int min_uV, int max_uV, unsigned *selector) +{ + struct vexpress_regulator *reg = rdev_get_drvdata(regdev); + + return vexpress_config_write(reg->func, 0, min_uV); +} + +static struct regulator_ops vexpress_regulator_ops_ro = { + .get_voltage = vexpress_regulator_get_voltage, +}; + +static struct regulator_ops vexpress_regulator_ops = { + .get_voltage = vexpress_regulator_get_voltage, + .set_voltage = vexpress_regulator_set_voltage, +}; + +static int vexpress_regulator_probe(struct platform_device *pdev) +{ + int err; + struct vexpress_regulator *reg; + struct regulator_init_data *init_data; + struct regulator_config config = { }; + + reg = devm_kzalloc(&pdev->dev, sizeof(*reg), GFP_KERNEL); + if (!reg) { + err = -ENOMEM; + goto error_kzalloc; + } + + reg->func = vexpress_config_func_get_by_dev(&pdev->dev); + if (!reg->func) { + err = -ENXIO; + goto error_get_func; + } + + reg->desc.name = dev_name(&pdev->dev); + reg->desc.type = REGULATOR_VOLTAGE; + reg->desc.owner = THIS_MODULE; + reg->desc.continuous_voltage_range = true; + + init_data = of_get_regulator_init_data(&pdev->dev, pdev->dev.of_node); + if (!init_data) { + err = -EINVAL; + goto error_get_regulator_init_data; + } + + init_data->constraints.apply_uV = 0; + if (init_data->constraints.min_uV && init_data->constraints.max_uV) + reg->desc.ops = &vexpress_regulator_ops; + else + reg->desc.ops = &vexpress_regulator_ops_ro; + + config.dev = &pdev->dev; + config.init_data = init_data; + config.driver_data = reg; + config.of_node = pdev->dev.of_node; + + reg->regdev = regulator_register(®->desc, &config); + if (IS_ERR(reg->regdev)) { + err = PTR_ERR(reg->regdev); + goto error_regulator_register; + } + + platform_set_drvdata(pdev, reg); + + return 0; + +error_regulator_register: +error_get_regulator_init_data: + vexpress_config_func_put(reg->func); +error_get_func: +error_kzalloc: + return err; +} + +static int __devexit vexpress_regulator_remove(struct platform_device *pdev) +{ + struct vexpress_regulator *reg = platform_get_drvdata(pdev); + + vexpress_config_func_put(reg->func); + regulator_unregister(reg->regdev); + + return 0; +} + +static struct of_device_id vexpress_regulator_of_match[] = { + { .compatible = "arm,vexpress-volt", }, +}; + +static struct platform_driver vexpress_regulator_driver = { + .probe = vexpress_regulator_probe, + .remove = __devexit_p(vexpress_regulator_remove), + .driver = { + .name = DRVNAME, + .owner = THIS_MODULE, + .of_match_table = vexpress_regulator_of_match, + }, +}; + +module_platform_driver(vexpress_regulator_driver); + +MODULE_AUTHOR("Pawel Moll "); +MODULE_DESCRIPTION("Versatile Express regulator"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:vexpress-regulator"); -- 2.7.4