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
|
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2019 Bootlin
* Author: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
*/
#include <linux/err.h>
#include <linux/gpio/driver.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#define LOGICVC_CTRL_REG 0x40
#define LOGICVC_CTRL_GPIO_SHIFT 11
#define LOGICVC_CTRL_GPIO_BITS 5
#define LOGICVC_POWER_CTRL_REG 0x78
#define LOGICVC_POWER_CTRL_GPIO_SHIFT 0
#define LOGICVC_POWER_CTRL_GPIO_BITS 4
struct logicvc_gpio {
struct gpio_chip chip;
struct regmap *regmap;
};
static void logicvc_gpio_offset(struct logicvc_gpio *logicvc, unsigned offset,
unsigned int *reg, unsigned int *bit)
{
if (offset >= LOGICVC_CTRL_GPIO_BITS) {
*reg = LOGICVC_POWER_CTRL_REG;
/* To the (virtual) power ctrl offset. */
offset -= LOGICVC_CTRL_GPIO_BITS;
/* To the actual bit offset in reg. */
offset += LOGICVC_POWER_CTRL_GPIO_SHIFT;
} else {
*reg = LOGICVC_CTRL_REG;
/* To the actual bit offset in reg. */
offset += LOGICVC_CTRL_GPIO_SHIFT;
}
*bit = BIT(offset);
}
static int logicvc_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct logicvc_gpio *logicvc = gpiochip_get_data(chip);
unsigned int reg, bit, value;
int ret;
logicvc_gpio_offset(logicvc, offset, ®, &bit);
ret = regmap_read(logicvc->regmap, reg, &value);
if (ret)
return ret;
return !!(value & bit);
}
static void logicvc_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct logicvc_gpio *logicvc = gpiochip_get_data(chip);
unsigned int reg, bit;
logicvc_gpio_offset(logicvc, offset, ®, &bit);
regmap_update_bits(logicvc->regmap, reg, bit, value ? bit : 0);
}
static int logicvc_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
/* Pins are always configured as output, so just set the value. */
logicvc_gpio_set(chip, offset, value);
return 0;
}
static struct regmap_config logicvc_gpio_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
.name = "logicvc-gpio",
};
static int logicvc_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *of_node = dev->of_node;
struct logicvc_gpio *logicvc;
int ret;
logicvc = devm_kzalloc(dev, sizeof(*logicvc), GFP_KERNEL);
if (!logicvc)
return -ENOMEM;
/* Try to get regmap from parent first. */
logicvc->regmap = syscon_node_to_regmap(of_node->parent);
/* Grab our own regmap if that fails. */
if (IS_ERR(logicvc->regmap)) {
struct resource res;
void __iomem *base;
ret = of_address_to_resource(of_node, 0, &res);
if (ret) {
dev_err(dev, "Failed to get resource from address\n");
return ret;
}
base = devm_ioremap_resource(dev, &res);
if (IS_ERR(base))
return PTR_ERR(base);
logicvc_gpio_regmap_config.max_register = resource_size(&res) -
logicvc_gpio_regmap_config.reg_stride;
logicvc->regmap =
devm_regmap_init_mmio(dev, base,
&logicvc_gpio_regmap_config);
if (IS_ERR(logicvc->regmap)) {
dev_err(dev, "Failed to create regmap for I/O\n");
return PTR_ERR(logicvc->regmap);
}
}
logicvc->chip.parent = dev;
logicvc->chip.owner = THIS_MODULE;
logicvc->chip.label = dev_name(dev);
logicvc->chip.base = -1;
logicvc->chip.ngpio = LOGICVC_CTRL_GPIO_BITS +
LOGICVC_POWER_CTRL_GPIO_BITS;
logicvc->chip.get = logicvc_gpio_get;
logicvc->chip.set = logicvc_gpio_set;
logicvc->chip.direction_output = logicvc_gpio_direction_output;
return devm_gpiochip_add_data(dev, &logicvc->chip, logicvc);
}
static const struct of_device_id logicivc_gpio_of_table[] = {
{
.compatible = "xylon,logicvc-3.02.a-gpio",
},
{ }
};
MODULE_DEVICE_TABLE(of, logicivc_gpio_of_table);
static struct platform_driver logicvc_gpio_driver = {
.driver = {
.name = "gpio-logicvc",
.of_match_table = logicivc_gpio_of_table,
},
.probe = logicvc_gpio_probe,
};
module_platform_driver(logicvc_gpio_driver);
MODULE_AUTHOR("Paul Kocialkowski <paul.kocialkowski@bootlin.com>");
MODULE_DESCRIPTION("Xylon LogiCVC GPIO driver");
MODULE_LICENSE("GPL");
|
