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
200
201
|
// SPDX-License-Identifier: GPL-2.0
/*
* NVMEM layout bus handling
*
* Copyright (C) 2023 Bootlin
* Author: Miquel Raynal <miquel.raynal@bootlin.com
*/
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/nvmem-consumer.h>
#include <linux/nvmem-provider.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include "internals.h"
#define to_nvmem_layout_driver(drv) \
(container_of((drv), struct nvmem_layout_driver, driver))
#define to_nvmem_layout_device(_dev) \
container_of((_dev), struct nvmem_layout, dev)
static int nvmem_layout_bus_match(struct device *dev, struct device_driver *drv)
{
return of_driver_match_device(dev, drv);
}
static int nvmem_layout_bus_probe(struct device *dev)
{
struct nvmem_layout_driver *drv = to_nvmem_layout_driver(dev->driver);
struct nvmem_layout *layout = to_nvmem_layout_device(dev);
if (!drv->probe || !drv->remove)
return -EINVAL;
return drv->probe(layout);
}
static void nvmem_layout_bus_remove(struct device *dev)
{
struct nvmem_layout_driver *drv = to_nvmem_layout_driver(dev->driver);
struct nvmem_layout *layout = to_nvmem_layout_device(dev);
return drv->remove(layout);
}
static const struct bus_type nvmem_layout_bus_type = {
.name = "nvmem-layout",
.match = nvmem_layout_bus_match,
.probe = nvmem_layout_bus_probe,
.remove = nvmem_layout_bus_remove,
};
int nvmem_layout_driver_register(struct nvmem_layout_driver *drv)
{
drv->driver.bus = &nvmem_layout_bus_type;
return driver_register(&drv->driver);
}
EXPORT_SYMBOL_GPL(nvmem_layout_driver_register);
void nvmem_layout_driver_unregister(struct nvmem_layout_driver *drv)
{
driver_unregister(&drv->driver);
}
EXPORT_SYMBOL_GPL(nvmem_layout_driver_unregister);
static void nvmem_layout_release_device(struct device *dev)
{
struct nvmem_layout *layout = to_nvmem_layout_device(dev);
of_node_put(layout->dev.of_node);
kfree(layout);
}
static int nvmem_layout_create_device(struct nvmem_device *nvmem,
struct device_node *np)
{
struct nvmem_layout *layout;
struct device *dev;
int ret;
layout = kzalloc(sizeof(*layout), GFP_KERNEL);
if (!layout)
return -ENOMEM;
/* Create a bidirectional link */
layout->nvmem = nvmem;
nvmem->layout = layout;
/* Device model registration */
dev = &layout->dev;
device_initialize(dev);
dev->parent = &nvmem->dev;
dev->bus = &nvmem_layout_bus_type;
dev->release = nvmem_layout_release_device;
dev->coherent_dma_mask = DMA_BIT_MASK(32);
dev->dma_mask = &dev->coherent_dma_mask;
device_set_node(dev, of_fwnode_handle(of_node_get(np)));
of_device_make_bus_id(dev);
of_msi_configure(dev, dev->of_node);
ret = device_add(dev);
if (ret) {
put_device(dev);
return ret;
}
return 0;
}
static const struct of_device_id of_nvmem_layout_skip_table[] = {
{ .compatible = "fixed-layout", },
{}
};
static int nvmem_layout_bus_populate(struct nvmem_device *nvmem,
struct device_node *layout_dn)
{
int ret;
/* Make sure it has a compatible property */
if (!of_get_property(layout_dn, "compatible", NULL)) {
pr_debug("%s() - skipping %pOF, no compatible prop\n",
__func__, layout_dn);
return 0;
}
/* Fixed layouts are parsed manually somewhere else for now */
if (of_match_node(of_nvmem_layout_skip_table, layout_dn)) {
pr_debug("%s() - skipping %pOF node\n", __func__, layout_dn);
return 0;
}
if (of_node_check_flag(layout_dn, OF_POPULATED_BUS)) {
pr_debug("%s() - skipping %pOF, already populated\n",
__func__, layout_dn);
return 0;
}
/* NVMEM layout buses expect only a single device representing the layout */
ret = nvmem_layout_create_device(nvmem, layout_dn);
if (ret)
return ret;
of_node_set_flag(layout_dn, OF_POPULATED_BUS);
return 0;
}
struct device_node *of_nvmem_layout_get_container(struct nvmem_device *nvmem)
{
return of_get_child_by_name(nvmem->dev.of_node, "nvmem-layout");
}
EXPORT_SYMBOL_GPL(of_nvmem_layout_get_container);
/*
* Returns the number of devices populated, 0 if the operation was not relevant
* for this nvmem device, an error code otherwise.
*/
int nvmem_populate_layout(struct nvmem_device *nvmem)
{
struct device_node *layout_dn;
int ret;
layout_dn = of_nvmem_layout_get_container(nvmem);
if (!layout_dn)
return 0;
/* Populate the layout device */
device_links_supplier_sync_state_pause();
ret = nvmem_layout_bus_populate(nvmem, layout_dn);
device_links_supplier_sync_state_resume();
of_node_put(layout_dn);
return ret;
}
void nvmem_destroy_layout(struct nvmem_device *nvmem)
{
struct device *dev;
if (!nvmem->layout)
return;
dev = &nvmem->layout->dev;
of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
device_unregister(dev);
}
int nvmem_layout_bus_register(void)
{
return bus_register(&nvmem_layout_bus_type);
}
void nvmem_layout_bus_unregister(void)
{
bus_unregister(&nvmem_layout_bus_type);
}
|
