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
|
// SPDX-License-Identifier: GPL-2.0
/*
* Turris Mox Moxtet GPIO expander
*
* Copyright (C) 2018 Marek Behún <kabel@kernel.org>
*/
#include <linux/bitops.h>
#include <linux/gpio/driver.h>
#include <linux/moxtet.h>
#include <linux/module.h>
#define MOXTET_GPIO_NGPIOS 12
#define MOXTET_GPIO_INPUTS 4
struct moxtet_gpio_desc {
u16 in_mask;
u16 out_mask;
};
static const struct moxtet_gpio_desc descs[] = {
[TURRIS_MOX_MODULE_SFP] = {
.in_mask = GENMASK(2, 0),
.out_mask = GENMASK(5, 4),
},
};
struct moxtet_gpio_chip {
struct device *dev;
struct gpio_chip gpio_chip;
const struct moxtet_gpio_desc *desc;
};
static int moxtet_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
{
struct moxtet_gpio_chip *chip = gpiochip_get_data(gc);
int ret;
if (chip->desc->in_mask & BIT(offset)) {
ret = moxtet_device_read(chip->dev);
} else if (chip->desc->out_mask & BIT(offset)) {
ret = moxtet_device_written(chip->dev);
if (ret >= 0)
ret <<= MOXTET_GPIO_INPUTS;
} else {
return -EINVAL;
}
if (ret < 0)
return ret;
return !!(ret & BIT(offset));
}
static void moxtet_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
int val)
{
struct moxtet_gpio_chip *chip = gpiochip_get_data(gc);
int state;
state = moxtet_device_written(chip->dev);
if (state < 0)
return;
offset -= MOXTET_GPIO_INPUTS;
if (val)
state |= BIT(offset);
else
state &= ~BIT(offset);
moxtet_device_write(chip->dev, state);
}
static int moxtet_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
{
struct moxtet_gpio_chip *chip = gpiochip_get_data(gc);
/* All lines are hard wired to be either input or output, not both. */
if (chip->desc->in_mask & BIT(offset))
return GPIO_LINE_DIRECTION_IN;
else if (chip->desc->out_mask & BIT(offset))
return GPIO_LINE_DIRECTION_OUT;
else
return -EINVAL;
}
static int moxtet_gpio_direction_input(struct gpio_chip *gc,
unsigned int offset)
{
struct moxtet_gpio_chip *chip = gpiochip_get_data(gc);
if (chip->desc->in_mask & BIT(offset))
return 0;
else if (chip->desc->out_mask & BIT(offset))
return -ENOTSUPP;
else
return -EINVAL;
}
static int moxtet_gpio_direction_output(struct gpio_chip *gc,
unsigned int offset, int val)
{
struct moxtet_gpio_chip *chip = gpiochip_get_data(gc);
if (chip->desc->out_mask & BIT(offset))
moxtet_gpio_set_value(gc, offset, val);
else if (chip->desc->in_mask & BIT(offset))
return -ENOTSUPP;
else
return -EINVAL;
return 0;
}
static int moxtet_gpio_probe(struct device *dev)
{
struct moxtet_gpio_chip *chip;
struct device_node *nc = dev->of_node;
int id;
id = to_moxtet_device(dev)->id;
if (id >= ARRAY_SIZE(descs)) {
dev_err(dev, "%pOF Moxtet device id 0x%x is not supported by gpio-moxtet driver\n",
nc, id);
return -ENOTSUPP;
}
chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->dev = dev;
chip->gpio_chip.parent = dev;
chip->desc = &descs[id];
dev_set_drvdata(dev, chip);
chip->gpio_chip.label = dev_name(dev);
chip->gpio_chip.get_direction = moxtet_gpio_get_direction;
chip->gpio_chip.direction_input = moxtet_gpio_direction_input;
chip->gpio_chip.direction_output = moxtet_gpio_direction_output;
chip->gpio_chip.get = moxtet_gpio_get_value;
chip->gpio_chip.set = moxtet_gpio_set_value;
chip->gpio_chip.base = -1;
chip->gpio_chip.ngpio = MOXTET_GPIO_NGPIOS;
chip->gpio_chip.can_sleep = true;
chip->gpio_chip.owner = THIS_MODULE;
return devm_gpiochip_add_data(dev, &chip->gpio_chip, chip);
}
static const struct of_device_id moxtet_gpio_dt_ids[] = {
{ .compatible = "cznic,moxtet-gpio", },
{},
};
MODULE_DEVICE_TABLE(of, moxtet_gpio_dt_ids);
static const enum turris_mox_module_id moxtet_gpio_module_table[] = {
TURRIS_MOX_MODULE_SFP,
0,
};
static struct moxtet_driver moxtet_gpio_driver = {
.driver = {
.name = "moxtet-gpio",
.of_match_table = moxtet_gpio_dt_ids,
.probe = moxtet_gpio_probe,
},
.id_table = moxtet_gpio_module_table,
};
module_moxtet_driver(moxtet_gpio_driver);
MODULE_AUTHOR("Marek Behun <kabel@kernel.org>");
MODULE_DESCRIPTION("Turris Mox Moxtet GPIO expander");
MODULE_LICENSE("GPL v2");
|
