regulator: Specify REGULATOR_CHANGE_STATUS for WM835x LED constraints
[safe/jmp/linux-2.6] / drivers / regulator / fixed.c
index 23d5546..f9f516a 100644 (file)
@@ -5,6 +5,9 @@
  *
  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
  *
+ * Copyright (c) 2009 Nokia Corporation
+ * Roger Quadros <ext-roger.quadros@nokia.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
 #include <linux/platform_device.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/fixed.h>
+#include <linux/gpio.h>
 
 struct fixed_voltage_data {
        struct regulator_desc desc;
        struct regulator_dev *dev;
        int microvolts;
+       int gpio;
+       unsigned enable_high:1;
+       unsigned is_enabled:1;
 };
 
 static int fixed_voltage_is_enabled(struct regulator_dev *dev)
 {
-       return 1;
+       struct fixed_voltage_data *data = rdev_get_drvdata(dev);
+
+       return data->is_enabled;
 }
 
 static int fixed_voltage_enable(struct regulator_dev *dev)
 {
+       struct fixed_voltage_data *data = rdev_get_drvdata(dev);
+
+       if (gpio_is_valid(data->gpio)) {
+               gpio_set_value_cansleep(data->gpio, data->enable_high);
+               data->is_enabled = 1;
+       }
+
+       return 0;
+}
+
+static int fixed_voltage_disable(struct regulator_dev *dev)
+{
+       struct fixed_voltage_data *data = rdev_get_drvdata(dev);
+
+       if (gpio_is_valid(data->gpio)) {
+               gpio_set_value_cansleep(data->gpio, !data->enable_high);
+               data->is_enabled = 0;
+       }
+
        return 0;
 }
 
@@ -44,10 +72,23 @@ static int fixed_voltage_get_voltage(struct regulator_dev *dev)
        return data->microvolts;
 }
 
+static int fixed_voltage_list_voltage(struct regulator_dev *dev,
+                                     unsigned selector)
+{
+       struct fixed_voltage_data *data = rdev_get_drvdata(dev);
+
+       if (selector != 0)
+               return -EINVAL;
+
+       return data->microvolts;
+}
+
 static struct regulator_ops fixed_voltage_ops = {
        .is_enabled = fixed_voltage_is_enabled,
        .enable = fixed_voltage_enable,
+       .disable = fixed_voltage_disable,
        .get_voltage = fixed_voltage_get_voltage,
+       .list_voltage = fixed_voltage_list_voltage,
 };
 
 static int regulator_fixed_voltage_probe(struct platform_device *pdev)
@@ -58,26 +99,79 @@ static int regulator_fixed_voltage_probe(struct platform_device *pdev)
 
        drvdata = kzalloc(sizeof(struct fixed_voltage_data), GFP_KERNEL);
        if (drvdata == NULL) {
+               dev_err(&pdev->dev, "Failed to allocate device data\n");
                ret = -ENOMEM;
                goto err;
        }
 
        drvdata->desc.name = kstrdup(config->supply_name, GFP_KERNEL);
        if (drvdata->desc.name == NULL) {
+               dev_err(&pdev->dev, "Failed to allocate supply name\n");
                ret = -ENOMEM;
                goto err;
        }
        drvdata->desc.type = REGULATOR_VOLTAGE;
        drvdata->desc.owner = THIS_MODULE;
-       drvdata->desc.ops = &fixed_voltage_ops,
+       drvdata->desc.ops = &fixed_voltage_ops;
+       drvdata->desc.n_voltages = 1;
 
        drvdata->microvolts = config->microvolts;
+       drvdata->gpio = config->gpio;
+
+       if (gpio_is_valid(config->gpio)) {
+               drvdata->enable_high = config->enable_high;
+
+               /* FIXME: Remove below print warning
+                *
+                * config->gpio must be set to -EINVAL by platform code if
+                * GPIO control is not required. However, early adopters
+                * not requiring GPIO control may forget to initialize
+                * config->gpio to -EINVAL. This will cause GPIO 0 to be used
+                * for GPIO control.
+                *
+                * This warning will be removed once there are a couple of users
+                * for this driver.
+                */
+               if (!config->gpio)
+                       dev_warn(&pdev->dev,
+                               "using GPIO 0 for regulator enable control\n");
+
+               ret = gpio_request(config->gpio, config->supply_name);
+               if (ret) {
+                       dev_err(&pdev->dev,
+                          "Could not obtain regulator enable GPIO %d: %d\n",
+                                                       config->gpio, ret);
+                       goto err_name;
+               }
+
+               /* set output direction without changing state
+                * to prevent glitch
+                */
+               drvdata->is_enabled = config->enabled_at_boot;
+               ret = drvdata->is_enabled ?
+                               config->enable_high : !config->enable_high;
+
+               ret = gpio_direction_output(config->gpio, ret);
+               if (ret) {
+                       dev_err(&pdev->dev,
+                          "Could not configure regulator enable GPIO %d direction: %d\n",
+                                                       config->gpio, ret);
+                       goto err_gpio;
+               }
+
+       } else {
+               /* Regulator without GPIO control is considered
+                * always enabled
+                */
+               drvdata->is_enabled = 1;
+       }
 
        drvdata->dev = regulator_register(&drvdata->desc, &pdev->dev,
                                          config->init_data, drvdata);
        if (IS_ERR(drvdata->dev)) {
                ret = PTR_ERR(drvdata->dev);
-               goto err_name;
+               dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
+               goto err_gpio;
        }
 
        platform_set_drvdata(pdev, drvdata);
@@ -87,6 +181,9 @@ static int regulator_fixed_voltage_probe(struct platform_device *pdev)
 
        return 0;
 
+err_gpio:
+       if (gpio_is_valid(config->gpio))
+               gpio_free(config->gpio);
 err_name:
        kfree(drvdata->desc.name);
 err:
@@ -99,6 +196,8 @@ static int regulator_fixed_voltage_remove(struct platform_device *pdev)
        struct fixed_voltage_data *drvdata = platform_get_drvdata(pdev);
 
        regulator_unregister(drvdata->dev);
+       if (gpio_is_valid(drvdata->gpio))
+               gpio_free(drvdata->gpio);
        kfree(drvdata->desc.name);
        kfree(drvdata);
 
@@ -117,7 +216,7 @@ static int __init regulator_fixed_voltage_init(void)
 {
        return platform_driver_register(&regulator_fixed_voltage_driver);
 }
-module_init(regulator_fixed_voltage_init);
+subsys_initcall(regulator_fixed_voltage_init);
 
 static void __exit regulator_fixed_voltage_exit(void)
 {
@@ -128,3 +227,4 @@ module_exit(regulator_fixed_voltage_exit);
 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 MODULE_DESCRIPTION("Fixed voltage regulator");
 MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:reg-fixed-voltage");