116 строки
2.8 KiB
C
116 строки
2.8 KiB
C
/*
|
|
* Generic Syscon Poweroff Driver
|
|
*
|
|
* Copyright (c) 2015, National Instruments Corp.
|
|
* Author: Moritz Fischer <moritz.fischer@ettus.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 program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
#include <linux/kallsyms.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/io.h>
|
|
#include <linux/notifier.h>
|
|
#include <linux/mfd/syscon.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/pm.h>
|
|
#include <linux/regmap.h>
|
|
|
|
static struct regmap *map;
|
|
static u32 offset;
|
|
static u32 value;
|
|
static u32 mask;
|
|
|
|
static void syscon_poweroff(void)
|
|
{
|
|
/* Issue the poweroff */
|
|
regmap_update_bits(map, offset, mask, value);
|
|
|
|
mdelay(1000);
|
|
|
|
pr_emerg("Unable to poweroff system\n");
|
|
}
|
|
|
|
static int syscon_poweroff_probe(struct platform_device *pdev)
|
|
{
|
|
char symname[KSYM_NAME_LEN];
|
|
int mask_err, value_err;
|
|
|
|
map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
|
|
if (IS_ERR(map)) {
|
|
dev_err(&pdev->dev, "unable to get syscon");
|
|
return PTR_ERR(map);
|
|
}
|
|
|
|
if (of_property_read_u32(pdev->dev.of_node, "offset", &offset)) {
|
|
dev_err(&pdev->dev, "unable to read 'offset'");
|
|
return -EINVAL;
|
|
}
|
|
|
|
value_err = of_property_read_u32(pdev->dev.of_node, "value", &value);
|
|
mask_err = of_property_read_u32(pdev->dev.of_node, "mask", &mask);
|
|
if (value_err && mask_err) {
|
|
dev_err(&pdev->dev, "unable to read 'value' and 'mask'");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (value_err) {
|
|
/* support old binding */
|
|
value = mask;
|
|
mask = 0xFFFFFFFF;
|
|
} else if (mask_err) {
|
|
/* support value without mask*/
|
|
mask = 0xFFFFFFFF;
|
|
}
|
|
|
|
if (pm_power_off) {
|
|
lookup_symbol_name((ulong)pm_power_off, symname);
|
|
dev_err(&pdev->dev,
|
|
"pm_power_off already claimed %p %s",
|
|
pm_power_off, symname);
|
|
return -EBUSY;
|
|
}
|
|
|
|
pm_power_off = syscon_poweroff;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int syscon_poweroff_remove(struct platform_device *pdev)
|
|
{
|
|
if (pm_power_off == syscon_poweroff)
|
|
pm_power_off = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id syscon_poweroff_of_match[] = {
|
|
{ .compatible = "syscon-poweroff" },
|
|
{}
|
|
};
|
|
|
|
static struct platform_driver syscon_poweroff_driver = {
|
|
.probe = syscon_poweroff_probe,
|
|
.remove = syscon_poweroff_remove,
|
|
.driver = {
|
|
.name = "syscon-poweroff",
|
|
.of_match_table = syscon_poweroff_of_match,
|
|
},
|
|
};
|
|
|
|
static int __init syscon_poweroff_register(void)
|
|
{
|
|
return platform_driver_register(&syscon_poweroff_driver);
|
|
}
|
|
device_initcall(syscon_poweroff_register);
|