Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 | /*
* 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 {
struct resource *mem;
void __iomem *base;
int irq;
const struct mfd_cell *cell;
struct device *hwmon;
struct completion read_completion;
struct mutex lock;
};
static ssize_t jz4740_hwmon_show_name(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
return sprintf(buf, "jz4740\n");
}
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 jz4740_hwmon_read_adcin(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct jz4740_hwmon *hwmon = dev_get_drvdata(dev);
struct completion *completion = &hwmon->read_completion;
long t;
unsigned long val;
int ret;
mutex_lock(&hwmon->lock);
INIT_COMPLETION(*completion);
enable_irq(hwmon->irq);
hwmon->cell->enable(to_platform_device(dev));
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(to_platform_device(dev));
disable_irq(hwmon->irq);
mutex_unlock(&hwmon->lock);
return ret;
}
static DEVICE_ATTR(name, S_IRUGO, jz4740_hwmon_show_name, NULL);
static DEVICE_ATTR(in0_input, S_IRUGO, jz4740_hwmon_read_adcin, NULL);
static struct attribute *jz4740_hwmon_attributes[] = {
&dev_attr_name.attr,
&dev_attr_in0_input.attr,
NULL
};
static const struct attribute_group jz4740_hwmon_attr_group = {
.attrs = jz4740_hwmon_attributes,
};
static int jz4740_hwmon_probe(struct platform_device *pdev)
{
int ret;
struct jz4740_hwmon *hwmon;
hwmon = devm_kzalloc(&pdev->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;
}
hwmon->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!hwmon->mem) {
dev_err(&pdev->dev, "Failed to get platform mmio resource\n");
return -ENOENT;
}
hwmon->mem = devm_request_mem_region(&pdev->dev, hwmon->mem->start,
resource_size(hwmon->mem), pdev->name);
if (!hwmon->mem) {
dev_err(&pdev->dev, "Failed to request mmio memory region\n");
return -EBUSY;
}
hwmon->base = devm_ioremap_nocache(&pdev->dev, hwmon->mem->start,
resource_size(hwmon->mem));
if (!hwmon->base) {
dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
return -EBUSY;
}
init_completion(&hwmon->read_completion);
mutex_init(&hwmon->lock);
platform_set_drvdata(pdev, hwmon);
ret = devm_request_irq(&pdev->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);
ret = sysfs_create_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
if (ret) {
dev_err(&pdev->dev, "Failed to create sysfs group: %d\n", ret);
return ret;
}
hwmon->hwmon = hwmon_device_register(&pdev->dev);
if (IS_ERR(hwmon->hwmon)) {
ret = PTR_ERR(hwmon->hwmon);
goto err_remove_file;
}
return 0;
err_remove_file:
sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
return ret;
}
static int jz4740_hwmon_remove(struct platform_device *pdev)
{
struct jz4740_hwmon *hwmon = platform_get_drvdata(pdev);
hwmon_device_unregister(hwmon->hwmon);
sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
return 0;
}
static struct platform_driver jz4740_hwmon_driver = {
.probe = jz4740_hwmon_probe,
.remove = jz4740_hwmon_remove,
.driver = {
.name = "jz4740-hwmon",
.owner = THIS_MODULE,
},
};
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");
|