linux/drivers/power/reset/syscon-poweroff.c
Thomas Gleixner c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 normalized pattern(s):

  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

  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 [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] 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

  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 [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00

107 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Generic Syscon Poweroff Driver
*
* Copyright (c) 2015, National Instruments Corp.
* Author: Moritz Fischer <moritz.fischer@ettus.com>
*/
#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);