Initial import

1 files changed, 349 insertions, 0 deletions

diff --git a/drivers/regulator/virtual.c b/drivers/regulator/virtual.c
new file mode 100644
index 000000000..a6f1c7a99
--- /dev/null
+++ b/drivers/regulator/virtual.c
@@ -0,0 +1,349 @@
+/*
+ * reg-virtual-consumer.c
+ *
+ * Copyright 2008 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ */
+
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+struct virtual_consumer_data {
+	struct mutex lock;
+	struct regulator *regulator;
+	bool enabled;
+	int min_uV;
+	int max_uV;
+	int min_uA;
+	int max_uA;
+	unsigned int mode;
+};
+
+static void update_voltage_constraints(struct device *dev,
+				       struct virtual_consumer_data *data)
+{
+	int ret;
+
+	if (data->min_uV && data->max_uV
+	    && data->min_uV <= data->max_uV) {
+		dev_dbg(dev, "Requesting %d-%duV\n",
+			data->min_uV, data->max_uV);
+		ret = regulator_set_voltage(data->regulator,
+					data->min_uV, data->max_uV);
+		if (ret != 0) {
+			dev_err(dev,
+				"regulator_set_voltage() failed: %d\n", ret);
+			return;
+		}
+	}
+
+	if (data->min_uV && data->max_uV && !data->enabled) {
+		dev_dbg(dev, "Enabling regulator\n");
+		ret = regulator_enable(data->regulator);
+		if (ret == 0)
+			data->enabled = true;
+		else
+			dev_err(dev, "regulator_enable() failed: %d\n",
+				ret);
+	}
+
+	if (!(data->min_uV && data->max_uV) && data->enabled) {
+		dev_dbg(dev, "Disabling regulator\n");
+		ret = regulator_disable(data->regulator);
+		if (ret == 0)
+			data->enabled = false;
+		else
+			dev_err(dev, "regulator_disable() failed: %d\n",
+				ret);
+	}
+}
+
+static void update_current_limit_constraints(struct device *dev,
+					  struct virtual_consumer_data *data)
+{
+	int ret;
+
+	if (data->max_uA
+	    && data->min_uA <= data->max_uA) {
+		dev_dbg(dev, "Requesting %d-%duA\n",
+			data->min_uA, data->max_uA);
+		ret = regulator_set_current_limit(data->regulator,
+					data->min_uA, data->max_uA);
+		if (ret != 0) {
+			dev_err(dev,
+				"regulator_set_current_limit() failed: %d\n",
+				ret);
+			return;
+		}
+	}
+
+	if (data->max_uA && !data->enabled) {
+		dev_dbg(dev, "Enabling regulator\n");
+		ret = regulator_enable(data->regulator);
+		if (ret == 0)
+			data->enabled = true;
+		else
+			dev_err(dev, "regulator_enable() failed: %d\n",
+				ret);
+	}
+
+	if (!(data->min_uA && data->max_uA) && data->enabled) {
+		dev_dbg(dev, "Disabling regulator\n");
+		ret = regulator_disable(data->regulator);
+		if (ret == 0)
+			data->enabled = false;
+		else
+			dev_err(dev, "regulator_disable() failed: %d\n",
+				ret);
+	}
+}
+
+static ssize_t show_min_uV(struct device *dev,
+			   struct device_attribute *attr, char *buf)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+	return sprintf(buf, "%d\n", data->min_uV);
+}
+
+static ssize_t set_min_uV(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+	long val;
+
+	if (kstrtol(buf, 10, &val) != 0)
+		return count;
+
+	mutex_lock(&data->lock);
+
+	data->min_uV = val;
+	update_voltage_constraints(dev, data);
+
+	mutex_unlock(&data->lock);
+
+	return count;
+}
+
+static ssize_t show_max_uV(struct device *dev,
+			   struct device_attribute *attr, char *buf)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+	return sprintf(buf, "%d\n", data->max_uV);
+}
+
+static ssize_t set_max_uV(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+	long val;
+
+	if (kstrtol(buf, 10, &val) != 0)
+		return count;
+
+	mutex_lock(&data->lock);
+
+	data->max_uV = val;
+	update_voltage_constraints(dev, data);
+
+	mutex_unlock(&data->lock);
+
+	return count;
+}
+
+static ssize_t show_min_uA(struct device *dev,
+			   struct device_attribute *attr, char *buf)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+	return sprintf(buf, "%d\n", data->min_uA);
+}
+
+static ssize_t set_min_uA(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+	long val;
+
+	if (kstrtol(buf, 10, &val) != 0)
+		return count;
+
+	mutex_lock(&data->lock);
+
+	data->min_uA = val;
+	update_current_limit_constraints(dev, data);
+
+	mutex_unlock(&data->lock);
+
+	return count;
+}
+
+static ssize_t show_max_uA(struct device *dev,
+			   struct device_attribute *attr, char *buf)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+	return sprintf(buf, "%d\n", data->max_uA);
+}
+
+static ssize_t set_max_uA(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+	long val;
+
+	if (kstrtol(buf, 10, &val) != 0)
+		return count;
+
+	mutex_lock(&data->lock);
+
+	data->max_uA = val;
+	update_current_limit_constraints(dev, data);
+
+	mutex_unlock(&data->lock);
+
+	return count;
+}
+
+static ssize_t show_mode(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+
+	switch (data->mode) {
+	case REGULATOR_MODE_FAST:
+		return sprintf(buf, "fast\n");
+	case REGULATOR_MODE_NORMAL:
+		return sprintf(buf, "normal\n");
+	case REGULATOR_MODE_IDLE:
+		return sprintf(buf, "idle\n");
+	case REGULATOR_MODE_STANDBY:
+		return sprintf(buf, "standby\n");
+	default:
+		return sprintf(buf, "unknown\n");
+	}
+}
+
+static ssize_t set_mode(struct device *dev, struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	struct virtual_consumer_data *data = dev_get_drvdata(dev);
+	unsigned int mode;
+	int ret;
+
+	/*
+	 * sysfs_streq() doesn't need the \n's, but we add them so the strings
+	 * will be shared with show_mode(), above.
+	 */
+	if (sysfs_streq(buf, "fast\n"))
+		mode = REGULATOR_MODE_FAST;
+	else if (sysfs_streq(buf, "normal\n"))
+		mode = REGULATOR_MODE_NORMAL;
+	else if (sysfs_streq(buf, "idle\n"))
+		mode = REGULATOR_MODE_IDLE;
+	else if (sysfs_streq(buf, "standby\n"))
+		mode = REGULATOR_MODE_STANDBY;
+	else {
+		dev_err(dev, "Configuring invalid mode\n");
+		return count;
+	}
+
+	mutex_lock(&data->lock);
+	ret = regulator_set_mode(data->regulator, mode);
+	if (ret == 0)
+		data->mode = mode;
+	else
+		dev_err(dev, "Failed to configure mode: %d\n", ret);
+	mutex_unlock(&data->lock);
+
+	return count;
+}
+
+static DEVICE_ATTR(min_microvolts, 0664, show_min_uV, set_min_uV);
+static DEVICE_ATTR(max_microvolts, 0664, show_max_uV, set_max_uV);
+static DEVICE_ATTR(min_microamps, 0664, show_min_uA, set_min_uA);
+static DEVICE_ATTR(max_microamps, 0664, show_max_uA, set_max_uA);
+static DEVICE_ATTR(mode, 0664, show_mode, set_mode);
+
+static struct attribute *regulator_virtual_attributes[] = {
+	&dev_attr_min_microvolts.attr,
+	&dev_attr_max_microvolts.attr,
+	&dev_attr_min_microamps.attr,
+	&dev_attr_max_microamps.attr,
+	&dev_attr_mode.attr,
+	NULL
+};
+
+static const struct attribute_group regulator_virtual_attr_group = {
+	.attrs	= regulator_virtual_attributes,
+};
+
+static int regulator_virtual_probe(struct platform_device *pdev)
+{
+	char *reg_id = dev_get_platdata(&pdev->dev);
+	struct virtual_consumer_data *drvdata;
+	int ret;
+
+	drvdata = devm_kzalloc(&pdev->dev, sizeof(struct virtual_consumer_data),
+			       GFP_KERNEL);
+	if (drvdata == NULL)
+		return -ENOMEM;
+
+	mutex_init(&drvdata->lock);
+
+	drvdata->regulator = devm_regulator_get(&pdev->dev, reg_id);
+	if (IS_ERR(drvdata->regulator)) {
+		ret = PTR_ERR(drvdata->regulator);
+		dev_err(&pdev->dev, "Failed to obtain supply '%s': %d\n",
+			reg_id, ret);
+		return ret;
+	}
+
+	ret = sysfs_create_group(&pdev->dev.kobj,
+				 &regulator_virtual_attr_group);
+	if (ret != 0) {
+		dev_err(&pdev->dev,
+			"Failed to create attribute group: %d\n", ret);
+		return ret;
+	}
+
+	drvdata->mode = regulator_get_mode(drvdata->regulator);
+
+	platform_set_drvdata(pdev, drvdata);
+
+	return 0;
+}
+
+static int regulator_virtual_remove(struct platform_device *pdev)
+{
+	struct virtual_consumer_data *drvdata = platform_get_drvdata(pdev);
+
+	sysfs_remove_group(&pdev->dev.kobj, &regulator_virtual_attr_group);
+
+	if (drvdata->enabled)
+		regulator_disable(drvdata->regulator);
+
+	return 0;
+}
+
+static struct platform_driver regulator_virtual_consumer_driver = {
+	.probe		= regulator_virtual_probe,
+	.remove		= regulator_virtual_remove,
+	.driver		= {
+		.name		= "reg-virt-consumer",
+	},
+};
+
+module_platform_driver(regulator_virtual_consumer_driver);
+
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("Virtual regulator consumer");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:reg-virt-consumer");