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path: root/drivers/regulator/virtual.c
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Diffstat (limited to 'drivers/regulator/virtual.c')
-rw-r--r--drivers/regulator/virtual.c345
1 files changed, 345 insertions, 0 deletions
diff --git a/drivers/regulator/virtual.c b/drivers/regulator/virtual.c
new file mode 100644
index 00000000000..5ddb464b1c3
--- /dev/null
+++ b/drivers/regulator/virtual.c
@@ -0,0 +1,345 @@
+/*
+ * 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>
+
+struct virtual_consumer_data {
+ struct mutex lock;
+ struct regulator *regulator;
+ int enabled;
+ int min_uV;
+ int max_uV;
+ int min_uA;
+ int max_uA;
+ unsigned int mode;
+};
+
+static void update_voltage_constraints(struct virtual_consumer_data *data)
+{
+ int ret;
+
+ if (data->min_uV && data->max_uV
+ && data->min_uV <= data->max_uV) {
+ ret = regulator_set_voltage(data->regulator,
+ data->min_uV, data->max_uV);
+ if (ret != 0) {
+ printk(KERN_ERR "regulator_set_voltage() failed: %d\n",
+ ret);
+ return;
+ }
+ }
+
+ if (data->min_uV && data->max_uV && !data->enabled) {
+ ret = regulator_enable(data->regulator);
+ if (ret == 0)
+ data->enabled = 1;
+ else
+ printk(KERN_ERR "regulator_enable() failed: %d\n",
+ ret);
+ }
+
+ if (!(data->min_uV && data->max_uV) && data->enabled) {
+ ret = regulator_disable(data->regulator);
+ if (ret == 0)
+ data->enabled = 0;
+ else
+ printk(KERN_ERR "regulator_disable() failed: %d\n",
+ ret);
+ }
+}
+
+static void update_current_limit_constraints(struct virtual_consumer_data
+ *data)
+{
+ int ret;
+
+ if (data->max_uA
+ && data->min_uA <= data->max_uA) {
+ ret = regulator_set_current_limit(data->regulator,
+ data->min_uA, data->max_uA);
+ if (ret != 0) {
+ pr_err("regulator_set_current_limit() failed: %d\n",
+ ret);
+ return;
+ }
+ }
+
+ if (data->max_uA && !data->enabled) {
+ ret = regulator_enable(data->regulator);
+ if (ret == 0)
+ data->enabled = 1;
+ else
+ printk(KERN_ERR "regulator_enable() failed: %d\n",
+ ret);
+ }
+
+ if (!(data->min_uA && data->max_uA) && data->enabled) {
+ ret = regulator_disable(data->regulator);
+ if (ret == 0)
+ data->enabled = 0;
+ else
+ printk(KERN_ERR "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 (strict_strtol(buf, 10, &val) != 0)
+ return count;
+
+ mutex_lock(&data->lock);
+
+ data->min_uV = val;
+ update_voltage_constraints(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 (strict_strtol(buf, 10, &val) != 0)
+ return count;
+
+ mutex_lock(&data->lock);
+
+ data->max_uV = val;
+ update_voltage_constraints(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 (strict_strtol(buf, 10, &val) != 0)
+ return count;
+
+ mutex_lock(&data->lock);
+
+ data->min_uA = val;
+ update_current_limit_constraints(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 (strict_strtol(buf, 10, &val) != 0)
+ return count;
+
+ mutex_lock(&data->lock);
+
+ data->max_uA = val;
+ update_current_limit_constraints(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;
+
+ if (strncmp(buf, "fast", strlen("fast")) == 0)
+ mode = REGULATOR_MODE_FAST;
+ else if (strncmp(buf, "normal", strlen("normal")) == 0)
+ mode = REGULATOR_MODE_NORMAL;
+ else if (strncmp(buf, "idle", strlen("idle")) == 0)
+ mode = REGULATOR_MODE_IDLE;
+ else if (strncmp(buf, "standby", strlen("standby")) == 0)
+ 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, 0666, show_min_uV, set_min_uV);
+static DEVICE_ATTR(max_microvolts, 0666, show_max_uV, set_max_uV);
+static DEVICE_ATTR(min_microamps, 0666, show_min_uA, set_min_uA);
+static DEVICE_ATTR(max_microamps, 0666, show_max_uA, set_max_uA);
+static DEVICE_ATTR(mode, 0666, show_mode, set_mode);
+
+struct device_attribute *attributes[] = {
+ &dev_attr_min_microvolts,
+ &dev_attr_max_microvolts,
+ &dev_attr_min_microamps,
+ &dev_attr_max_microamps,
+ &dev_attr_mode,
+};
+
+static int regulator_virtual_consumer_probe(struct platform_device *pdev)
+{
+ char *reg_id = pdev->dev.platform_data;
+ struct virtual_consumer_data *drvdata;
+ int ret, i;
+
+ drvdata = kzalloc(sizeof(struct virtual_consumer_data), GFP_KERNEL);
+ if (drvdata == NULL) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ mutex_init(&drvdata->lock);
+
+ drvdata->regulator = regulator_get(&pdev->dev, reg_id);
+ if (IS_ERR(drvdata->regulator)) {
+ ret = PTR_ERR(drvdata->regulator);
+ goto err;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(attributes); i++) {
+ ret = device_create_file(&pdev->dev, attributes[i]);
+ if (ret != 0)
+ goto err;
+ }
+
+ drvdata->mode = regulator_get_mode(drvdata->regulator);
+
+ platform_set_drvdata(pdev, drvdata);
+
+ return 0;
+
+err:
+ for (i = 0; i < ARRAY_SIZE(attributes); i++)
+ device_remove_file(&pdev->dev, attributes[i]);
+ kfree(drvdata);
+ return ret;
+}
+
+static int regulator_virtual_consumer_remove(struct platform_device *pdev)
+{
+ struct virtual_consumer_data *drvdata = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(attributes); i++)
+ device_remove_file(&pdev->dev, attributes[i]);
+ if (drvdata->enabled)
+ regulator_disable(drvdata->regulator);
+ regulator_put(drvdata->regulator);
+
+ kfree(drvdata);
+
+ return 0;
+}
+
+static struct platform_driver regulator_virtual_consumer_driver = {
+ .probe = regulator_virtual_consumer_probe,
+ .remove = regulator_virtual_consumer_remove,
+ .driver = {
+ .name = "reg-virt-consumer",
+ },
+};
+
+
+static int __init regulator_virtual_consumer_init(void)
+{
+ return platform_driver_register(&regulator_virtual_consumer_driver);
+}
+module_init(regulator_virtual_consumer_init);
+
+static void __exit regulator_virtual_consumer_exit(void)
+{
+ platform_driver_unregister(&regulator_virtual_consumer_driver);
+}
+module_exit(regulator_virtual_consumer_exit);
+
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("Virtual regulator consumer");
+MODULE_LICENSE("GPL");