linux_old1/drivers/regulator/fixed.c

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/*
* fixed.c
*
* Copyright 2008 Wolfson Microelectronics PLC.
*
* 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
* License, or (at your option) any later version.
*
* This is useful for systems with mixed controllable and
* non-controllable regulators, as well as for allowing testing on
* systems with no controllable regulators.
*/
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/fixed.h>
#include <linux/gpio.h>
#include <linux/delay.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regulator/machine.h>
struct fixed_voltage_data {
struct regulator_desc desc;
struct regulator_dev *dev;
int microvolts;
int gpio;
unsigned startup_delay;
bool enable_high;
bool is_enabled;
};
/**
* of_get_fixed_voltage_config - extract fixed_voltage_config structure info
* @dev: device requesting for fixed_voltage_config
*
* Populates fixed_voltage_config structure by extracting data from device
* tree node, returns a pointer to the populated structure of NULL if memory
* alloc fails.
*/
static struct fixed_voltage_config *
of_get_fixed_voltage_config(struct device *dev)
{
struct fixed_voltage_config *config;
struct device_node *np = dev->of_node;
const __be32 *delay;
struct regulator_init_data *init_data;
config = devm_kzalloc(dev, sizeof(struct fixed_voltage_config),
GFP_KERNEL);
if (!config)
return NULL;
config->init_data = of_get_regulator_init_data(dev, dev->of_node);
if (!config->init_data)
return NULL;
init_data = config->init_data;
init_data->constraints.apply_uV = 0;
config->supply_name = init_data->constraints.name;
if (init_data->constraints.min_uV == init_data->constraints.max_uV) {
config->microvolts = init_data->constraints.min_uV;
} else {
dev_err(dev,
"Fixed regulator specified with variable voltages\n");
return NULL;
}
if (init_data->constraints.boot_on)
config->enabled_at_boot = true;
config->gpio = of_get_named_gpio(np, "gpio", 0);
delay = of_get_property(np, "startup-delay-us", NULL);
if (delay)
config->startup_delay = be32_to_cpu(*delay);
if (of_find_property(np, "enable-active-high", NULL))
config->enable_high = true;
return config;
}
static int fixed_voltage_is_enabled(struct regulator_dev *dev)
{
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);
gpio_set_value_cansleep(data->gpio, data->enable_high);
data->is_enabled = true;
return 0;
}
static int fixed_voltage_disable(struct regulator_dev *dev)
{
struct fixed_voltage_data *data = rdev_get_drvdata(dev);
gpio_set_value_cansleep(data->gpio, !data->enable_high);
data->is_enabled = false;
return 0;
}
static int fixed_voltage_enable_time(struct regulator_dev *dev)
{
struct fixed_voltage_data *data = rdev_get_drvdata(dev);
return data->startup_delay;
}
static int fixed_voltage_get_voltage(struct regulator_dev *dev)
{
struct fixed_voltage_data *data = rdev_get_drvdata(dev);
if (data->microvolts)
return data->microvolts;
else
return -EINVAL;
}
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_gpio_ops = {
.is_enabled = fixed_voltage_is_enabled,
.enable = fixed_voltage_enable,
.disable = fixed_voltage_disable,
.enable_time = fixed_voltage_enable_time,
.get_voltage = fixed_voltage_get_voltage,
.list_voltage = fixed_voltage_list_voltage,
};
static struct regulator_ops fixed_voltage_ops = {
.get_voltage = fixed_voltage_get_voltage,
.list_voltage = fixed_voltage_list_voltage,
};
static int __devinit reg_fixed_voltage_probe(struct platform_device *pdev)
{
struct fixed_voltage_config *config;
struct fixed_voltage_data *drvdata;
struct regulator_config cfg = { };
int ret;
if (pdev->dev.of_node)
config = of_get_fixed_voltage_config(&pdev->dev);
else
config = pdev->dev.platform_data;
if (!config)
return -ENOMEM;
drvdata = devm_kzalloc(&pdev->dev, 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;
if (config->microvolts)
drvdata->desc.n_voltages = 1;
drvdata->microvolts = config->microvolts;
drvdata->gpio = config->gpio;
drvdata->startup_delay = config->startup_delay;
if (gpio_is_valid(config->gpio)) {
int gpio_flag;
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");
/*
* 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;
gpio_flag = ret ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
if (config->gpio_is_open_drain)
gpio_flag |= GPIOF_OPEN_DRAIN;
ret = gpio_request_one(config->gpio, gpio_flag,
config->supply_name);
if (ret) {
dev_err(&pdev->dev,
"Could not obtain regulator enable GPIO %d: %d\n",
config->gpio, ret);
goto err_name;
}
drvdata->desc.ops = &fixed_voltage_gpio_ops;
} else {
drvdata->desc.ops = &fixed_voltage_ops;
}
cfg.dev = &pdev->dev;
cfg.init_data = config->init_data;
cfg.driver_data = drvdata;
cfg.of_node = pdev->dev.of_node;
drvdata->dev = regulator_register(&drvdata->desc, &cfg);
if (IS_ERR(drvdata->dev)) {
ret = PTR_ERR(drvdata->dev);
dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
goto err_gpio;
}
platform_set_drvdata(pdev, drvdata);
dev_dbg(&pdev->dev, "%s supplying %duV\n", drvdata->desc.name,
drvdata->microvolts);
return 0;
err_gpio:
if (gpio_is_valid(config->gpio))
gpio_free(config->gpio);
err_name:
kfree(drvdata->desc.name);
err:
return ret;
}
static int __devexit reg_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);
return 0;
}
#if defined(CONFIG_OF)
static const struct of_device_id fixed_of_match[] __devinitconst = {
{ .compatible = "regulator-fixed", },
{},
};
MODULE_DEVICE_TABLE(of, fixed_of_match);
#else
#define fixed_of_match NULL
#endif
static struct platform_driver regulator_fixed_voltage_driver = {
.probe = reg_fixed_voltage_probe,
.remove = __devexit_p(reg_fixed_voltage_remove),
.driver = {
.name = "reg-fixed-voltage",
.owner = THIS_MODULE,
.of_match_table = fixed_of_match,
},
};
static int __init regulator_fixed_voltage_init(void)
{
return platform_driver_register(&regulator_fixed_voltage_driver);
}
subsys_initcall(regulator_fixed_voltage_init);
static void __exit regulator_fixed_voltage_exit(void)
{
platform_driver_unregister(&regulator_fixed_voltage_driver);
}
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");