/*
* wm831x-isink.c -- Current sink driver for the WM831x series
*
* Copyright 2009 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/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/slab.h>
#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/regulator.h>
#include <linux/mfd/wm831x/pdata.h>
#define WM831X_ISINK_MAX_NAME 7
struct wm831x_isink {
char name[WM831X_ISINK_MAX_NAME];
struct regulator_desc desc;
int reg;
struct wm831x *wm831x;
struct regulator_dev *regulator;
};
static int wm831x_isink_enable(struct regulator_dev *rdev)
{
struct wm831x_isink *isink = rdev_get_drvdata(rdev);
struct wm831x *wm831x = isink->wm831x;
int ret;
/* We have a two stage enable: first start the ISINK... */
ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA,
WM831X_CS1_ENA);
if (ret != 0)
return ret;
/* ...then enable drive */
ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE,
WM831X_CS1_DRIVE);
if (ret != 0)
wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);
return ret;
}
static int wm831x_isink_disable(struct regulator_dev *rdev)
{
struct wm831x_isink *isink = rdev_get_drvdata(rdev);
struct wm831x *wm831x = isink->wm831x;
int ret;
ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE, 0);
if (ret < 0)
return ret;
ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);
if (ret < 0)
return ret;
return ret;
}
static int wm831x_isink_is_enabled(struct regulator_dev *rdev)
{
struct wm831x_isink *isink = rdev_get_drvdata(rdev);
struct wm831x *wm831x = isink->wm831x;
int ret;
ret = wm831x_reg_read(wm831x, isink->reg);
if (ret < 0)
return ret;
if ((ret & (WM831X_CS1_ENA | WM831X_CS1_DRIVE)) ==
(WM831X_CS1_ENA | WM831X_CS1_DRIVE))
return 1;
else
return 0;
}
static int wm831x_isink_set_current(struct regulator_dev *rdev,
int min_uA, int max_uA)
{
struct wm831x_isink *isink = rdev_get_drvdata(rdev);
struct wm831x *wm831x = isink->wm831x;
int ret, i;
for (i = 0; i < ARRAY_SIZE(wm831x_isinkv_values); i++) {
int val = wm831x_isinkv_values[i];
if (min_uA >= val && val <= max_uA) {
ret = wm831x_set_bits(wm831x, isink->reg,
WM831X_CS1_ISEL_MASK, i);
return ret;
}
}
return -EINVAL;
}
static int wm831x_isink_get_current(struct regulator_dev *rdev)
{
struct wm831x_isink *isink = rdev_get_drvdata(rdev);
struct wm831x *wm831x = isink->wm831x;
int ret;
ret = wm831x_reg_read(wm831x, isink->reg);
if (ret < 0)
return ret;
ret &= WM831X_CS1_ISEL_MASK;
if (ret > WM831X_ISINK_MAX_ISEL)
ret = WM831X_ISINK_MAX_ISEL;
return wm831x_isinkv_values[ret];
}
static struct regulator_ops wm831x_isink_ops = {
.is_enabled = wm831x_isink_is_enabled,
.enable = wm831x_isink_enable,
.disable = wm831x_isink_disable,
.set_current_limit = wm831x_isink_set_current,
.get_current_limit = wm831x_isink_get_current,
};
static irqreturn_t wm831x_isink_irq(int irq, void *data)
{
struct wm831x_isink *isink = data;
regulator_notifier_call_chain(isink->regulator,
REGULATOR_EVENT_OVER_CURRENT,
NULL);
return IRQ_HANDLED;
}
static __devinit int wm831x_isink_probe(struct platform_device *pdev)
{
struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
struct wm831x_pdata *pdata = wm831x->dev->platform_data;
struct wm831x_isink *isink;
int id = pdev->id % ARRAY_SIZE(pdata->isink);
struct resource *res;
int ret, irq;
dev_dbg(&pdev->dev, "Probing ISINK%d\n", id + 1);
if (pdata == NULL || pdata->isink[id] == NULL)
return -ENODEV;
isink = kzalloc(sizeof(struct wm831x_isink), GFP_KERNEL);
if (isink == NULL) {
dev_err(&pdev->dev, "Unable to allocate private data\n");
return -ENOMEM;
}
isink->wm831x = wm831x;
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (res == NULL) {
dev_err(&pdev->dev, "No I/O resource\n");
ret = -EINVAL;
goto err;
}
isink->reg = res->start;
/* For current parts this is correct; probably need to revisit
* in future.
*/
snprintf(isink->name, sizeof(isink->name), "ISINK%d", id + 1);
isink->desc.name = isink->name;
isink->desc.id = id;
isink->desc.ops = &wm831x_isink_ops;
isink->desc.type = REGULATOR_CURRENT;
isink->desc.owner = THIS_MODULE;
isink->regulator = regulator_register(&isink->desc, &pdev->dev,
pdata->isink[id], isink);
if (IS_ERR(isink->regulator)) {
ret = PTR_ERR(isink->regulator);
dev_err(wm831x->dev, "Failed to register ISINK%d: %d\n",
id + 1, ret);
goto err;
}
irq = platform_get_irq(pdev, 0);
ret = request_threaded_irq(irq, NULL, wm831x_isink_irq,
IRQF_TRIGGER_RISING, isink->name, isink);
if (ret != 0) {
dev_err(&pdev->dev, "Failed to request ISINK IRQ %d: %d\n",
irq, ret);
goto err_regulator;
}
platform_set_drvdata(pdev, isink);
return 0;
err_regulator:
regulator_unregister(isink->regulator);
err:
kfree(isink);
return ret;
}
static __devexit int wm831x_isink_remove(struct platform_device *pdev)
{
struct wm831x_isink *isink = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, NULL);
free_irq(platform_get_irq(pdev, 0), isink);
regulator_unregister(isink->regulator);
kfree(isink);
return 0;
}
static struct platform_driver wm831x_isink_driver = {
.probe = wm831x_isink_probe,
.remove = __devexit_p(wm831x_isink_remove),
.driver = {
.name = "wm831x-isink",
.owner = THIS_MODULE,
},
};
static int __init wm831x_isink_init(void)
{
int ret;
ret = platform_driver_register(&wm831x_isink_driver);
if (ret != 0)
pr_err("Failed to register WM831x ISINK driver: %d\n", ret);
return ret;
}
subsys_initcall(wm831x_isink_init);
static void __exit wm831x_isink_exit(void)
{
platform_driver_unregister(&wm831x_isink_driver);
}
module_exit(wm831x_isink_exit);
/* Module information */
MODULE_AUTHOR("Mark Brown");
MODULE_DESCRIPTION("WM831x current sink driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-isink");
