diff options
Diffstat (limited to 'drivers/regulator/vexpress.c')
| -rw-r--r-- | drivers/regulator/vexpress.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/regulator/vexpress.c b/drivers/regulator/vexpress.c new file mode 100644 index 000000000000..4668c7f8133d --- /dev/null +++ b/drivers/regulator/vexpress.c @@ -0,0 +1,147 @@ +/* + * 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 <linux/device.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/regulator/driver.h> +#include <linux/regulator/machine.h> +#include <linux/regulator/of_regulator.h> +#include <linux/vexpress.h> + +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 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 = 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 <pawel.moll@arm.com>"); +MODULE_DESCRIPTION("Versatile Express regulator"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:vexpress-regulator"); |