147 lines
3.4 KiB
C
147 lines
3.4 KiB
C
/*
|
|
* Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
|
|
* JZ4740 SoC HWMON driver
|
|
*
|
|
* 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.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*
|
|
*/
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/io.h>
|
|
|
|
#include <linux/completion.h>
|
|
#include <linux/mfd/core.h>
|
|
|
|
#include <linux/hwmon.h>
|
|
|
|
struct jz4740_hwmon {
|
|
void __iomem *base;
|
|
int irq;
|
|
const struct mfd_cell *cell;
|
|
struct platform_device *pdev;
|
|
struct completion read_completion;
|
|
struct mutex lock;
|
|
};
|
|
|
|
static irqreturn_t jz4740_hwmon_irq(int irq, void *data)
|
|
{
|
|
struct jz4740_hwmon *hwmon = data;
|
|
|
|
complete(&hwmon->read_completion);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static ssize_t in0_input_show(struct device *dev,
|
|
struct device_attribute *dev_attr, char *buf)
|
|
{
|
|
struct jz4740_hwmon *hwmon = dev_get_drvdata(dev);
|
|
struct platform_device *pdev = hwmon->pdev;
|
|
struct completion *completion = &hwmon->read_completion;
|
|
long t;
|
|
unsigned long val;
|
|
int ret;
|
|
|
|
mutex_lock(&hwmon->lock);
|
|
|
|
reinit_completion(completion);
|
|
|
|
enable_irq(hwmon->irq);
|
|
hwmon->cell->enable(pdev);
|
|
|
|
t = wait_for_completion_interruptible_timeout(completion, HZ);
|
|
|
|
if (t > 0) {
|
|
val = readw(hwmon->base) & 0xfff;
|
|
val = (val * 3300) >> 12;
|
|
ret = sprintf(buf, "%lu\n", val);
|
|
} else {
|
|
ret = t ? t : -ETIMEDOUT;
|
|
}
|
|
|
|
hwmon->cell->disable(pdev);
|
|
disable_irq(hwmon->irq);
|
|
|
|
mutex_unlock(&hwmon->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static DEVICE_ATTR_RO(in0_input);
|
|
|
|
static struct attribute *jz4740_attrs[] = {
|
|
&dev_attr_in0_input.attr,
|
|
NULL
|
|
};
|
|
|
|
ATTRIBUTE_GROUPS(jz4740);
|
|
|
|
static int jz4740_hwmon_probe(struct platform_device *pdev)
|
|
{
|
|
int ret;
|
|
struct device *dev = &pdev->dev;
|
|
struct jz4740_hwmon *hwmon;
|
|
struct device *hwmon_dev;
|
|
struct resource *mem;
|
|
|
|
hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL);
|
|
if (!hwmon)
|
|
return -ENOMEM;
|
|
|
|
hwmon->cell = mfd_get_cell(pdev);
|
|
|
|
hwmon->irq = platform_get_irq(pdev, 0);
|
|
if (hwmon->irq < 0) {
|
|
dev_err(&pdev->dev, "Failed to get platform irq: %d\n",
|
|
hwmon->irq);
|
|
return hwmon->irq;
|
|
}
|
|
|
|
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
hwmon->base = devm_ioremap_resource(&pdev->dev, mem);
|
|
if (IS_ERR(hwmon->base))
|
|
return PTR_ERR(hwmon->base);
|
|
|
|
hwmon->pdev = pdev;
|
|
init_completion(&hwmon->read_completion);
|
|
mutex_init(&hwmon->lock);
|
|
|
|
ret = devm_request_irq(dev, hwmon->irq, jz4740_hwmon_irq, 0,
|
|
pdev->name, hwmon);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "Failed to request irq: %d\n", ret);
|
|
return ret;
|
|
}
|
|
disable_irq(hwmon->irq);
|
|
|
|
hwmon_dev = devm_hwmon_device_register_with_groups(dev, "jz4740", hwmon,
|
|
jz4740_groups);
|
|
return PTR_ERR_OR_ZERO(hwmon_dev);
|
|
}
|
|
|
|
static struct platform_driver jz4740_hwmon_driver = {
|
|
.probe = jz4740_hwmon_probe,
|
|
.driver = {
|
|
.name = "jz4740-hwmon",
|
|
},
|
|
};
|
|
|
|
module_platform_driver(jz4740_hwmon_driver);
|
|
|
|
MODULE_DESCRIPTION("JZ4740 SoC HWMON driver");
|
|
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:jz4740-hwmon");
|