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
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) Vaisala Oyj. All rights reserved.
*/
#include <common.h>
#include <init.h>
#include <of.h>
#include <linux/nvmem-consumer.h>
#include <linux/reboot-mode.h>
struct nvmem_reboot_mode {
struct reboot_mode_driver reboot;
struct nvmem_cell *cell;
};
static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot,
const u32 *_magic)
{
struct nvmem_reboot_mode *nvmem_rbm;
u32 magic = *_magic;
int ret;
nvmem_rbm = container_of(reboot, struct nvmem_reboot_mode, reboot);
ret = nvmem_cell_write(nvmem_rbm->cell, &magic, sizeof(magic));
if (ret < 0)
dev_err(reboot->dev, "update reboot mode bits failed: %pe\n", ERR_PTR(ret));
else if (ret != 4)
ret = -EIO;
else
ret = 0;
return ret;
}
static int nvmem_reboot_mode_probe(struct device_d *dev)
{
struct nvmem_reboot_mode *nvmem_rbm;
struct nvmem_cell *cell;
void *magicbuf;
size_t len;
int ret;
cell = nvmem_cell_get(dev, "reboot-mode");
if (IS_ERR(cell)) {
ret = PTR_ERR(cell);
if (ret != -EPROBE_DEFER)
dev_err(dev, "failed to get the nvmem cell reboot-mode: %pe\n", cell);
return ret;
}
nvmem_rbm = xzalloc(sizeof(*nvmem_rbm));
nvmem_rbm->cell = cell;
nvmem_rbm->reboot.dev = dev;
nvmem_rbm->reboot.write = nvmem_reboot_mode_write;
nvmem_rbm->reboot.priority = 200;
/*
* Fixing up the nvmem reboot device tree node is problematic, because it
* contains a phandle to another node. Take the easy way out for now and
* expect user to provide matching reboot-mode nodes in both kernel and
* barebox device tree manually.
*/
nvmem_rbm->reboot.no_fixup = true;
magicbuf = nvmem_cell_read(nvmem_rbm->cell, &len);
if (IS_ERR(magicbuf) || len != 4) {
dev_err(dev, "error reading reboot mode: %pe\n", magicbuf);
return PTR_ERR(magicbuf);
}
ret = reboot_mode_register(&nvmem_rbm->reboot, magicbuf, 1);
if (ret)
dev_err(dev, "can't register reboot mode\n");
return ret;
}
static const struct of_device_id nvmem_reboot_mode_of_match[] = {
{ .compatible = "nvmem-reboot-mode" },
{ /* sentinel */ }
};
static struct driver_d nvmem_reboot_mode_driver = {
.probe = nvmem_reboot_mode_probe,
.name = "nvmem-reboot-mode",
.of_compatible = nvmem_reboot_mode_of_match,
};
coredevice_platform_driver(nvmem_reboot_mode_driver);
|
